Compare commits

...

12 Commits
main ... antora

Author SHA1 Message Date
Marcin Grzejszczak 40ba25e13f Fixed readme 1 year ago
Marcin Grzejszczak 96d67fb841 It's alive 1 year ago
Marcin Grzejszczak 8a744e57c5 Enable Section Summary TOC for small pages 1 year ago
Marcin Grzejszczak 90a2d8f49f Fix cross references 1 year ago
Marcin Grzejszczak 16503b67f7 Remove includes 1 year ago
Marcin Grzejszczak fabf5dcaf9 Generate a default navigation 1 year ago
Marcin Grzejszczak 0701a2b239 Split files 1 year ago
Marcin Grzejszczak a0151e94ef Fix indentation for all pages 1 year ago
Marcin Grzejszczak fd416d01a9 Copy default antora files 1 year ago
Marcin Grzejszczak 30216957ee Remove unnecessary asciidoc attributes 1 year ago
Marcin Grzejszczak ad4c551827 Insert explicit ids for headers 1 year ago
Marcin Grzejszczak f32862244e Migrate Structure 1 year ago
  1. 33
      .github/workflows/deploy-docs.yml
  2. 9
      .gitignore
  3. 336
      README.adoc
  4. 38
      docs/antora-playbook.yml
  5. 12
      docs/antora.yml
  6. 11
      docs/modules/ROOT/nav.adoc
  7. 12
      docs/modules/ROOT/pages/appendix.adoc
  8. 6
      docs/modules/ROOT/pages/configprops.adoc
  9. 9
      docs/modules/ROOT/pages/index.adoc
  10. 3
      docs/modules/ROOT/pages/intro.adoc
  11. 15
      docs/modules/ROOT/pages/spring-cloud-circuitbreaker.adoc
  12. 254
      docs/modules/ROOT/pages/spring-cloud-commons/application-context-services.adoc
  13. 15
      docs/modules/ROOT/pages/spring-cloud-commons/cachedrandompropertysource.adoc
  14. 595
      docs/modules/ROOT/pages/spring-cloud-commons/common-abstractions.adoc
  15. 515
      docs/modules/ROOT/pages/spring-cloud-commons/loadbalancer.adoc
  16. 89
      docs/modules/ROOT/pages/spring-cloud-commons/security.adoc
  17. 3
      docs/modules/ROOT/partials/_attributes.adoc
  18. 37
      docs/pom.xml
  19. 20
      docs/src/main/antora/resources/antora-resources/antora.yml
  20. 9
      docs/src/main/asciidoc/README.adoc
  21. 16
      docs/src/main/asciidoc/_attributes.adoc
  22. 83
      docs/src/main/asciidoc/_configprops.adoc
  23. 8
      docs/src/main/asciidoc/_observability.adoc
  24. 330
      docs/src/main/asciidoc/ghpages.sh
  25. 1
      docs/src/main/asciidoc/index.adoc
  26. 8
      docs/src/main/asciidoc/jce.adoc
  27. 1478
      docs/src/main/asciidoc/spring-cloud-commons.adoc

33
.github/workflows/deploy-docs.yml

@ -0,0 +1,33 @@ @@ -0,0 +1,33 @@
name: Deploy Docs
on:
push:
branches-ignore: [ gh-pages ]
tags: '**'
repository_dispatch:
types: request-build-reference # legacy
#schedule:
#- cron: '0 10 * * *' # Once per day at 10am UTC
workflow_dispatch:
permissions:
actions: write
jobs:
build:
runs-on: ubuntu-latest
# FIXME: enable when pushed to spring-projects
# if: github.repository_owner == 'spring-projects'
steps:
- name: Checkout
uses: actions/checkout@v3
with:
ref: docs-build
fetch-depth: 1
- name: Dispatch (partial build)
if: github.ref_type == 'branch'
env:
GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
run: gh workflow run deploy-docs.yml -r $(git rev-parse --abbrev-ref HEAD) -f build-refname=${{ github.ref_name }}
- name: Dispatch (full build)
if: github.ref_type == 'tag'
env:
GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
run: gh workflow run deploy-docs.yml -r $(git rev-parse --abbrev-ref HEAD)

9
.gitignore vendored

@ -21,3 +21,12 @@ _site/ @@ -21,3 +21,12 @@ _site/
antrun
.vscode/
.flattened-pom.xml
node
node_modules
build
_configprops.adoc
_spans.adoc
_metrics.adoc
_conventions.adoc
package.json
package-lock.json

336
README.adoc

@ -6,334 +6,14 @@ Edit the files in the src/main/asciidoc/ directory instead. @@ -6,334 +6,14 @@ Edit the files in the src/main/asciidoc/ directory instead.
https://pivotal.io/platform-as-a-service/migrating-to-cloud-native-application-architectures-ebook[Cloud Native] is a style of application development that encourages easy adoption of best practices in the areas of continuous delivery and value-driven development.
A related discipline is that of building https://12factor.net/[12-factor Applications], in which development practices are aligned with delivery and operations goals -- for instance, by using declarative programming and management and monitoring.
Spring Cloud facilitates these styles of development in a number of specific ways.
The starting point is a set of features to which all components in a distributed system need easy access.
[[building]]
= Building
:page-section-summary-toc: 1
Many of those features are covered by https://projects.spring.io/spring-boot[Spring Boot], on which Spring Cloud builds. Some more features are delivered by Spring Cloud as two libraries: Spring Cloud Context and Spring Cloud Commons.
Spring Cloud Context provides utilities and special services for the `ApplicationContext` of a Spring Cloud application (bootstrap context, encryption, refresh scope, and environment endpoints). Spring Cloud Commons is a set of abstractions and common classes used in different Spring Cloud implementations (such as Spring Cloud Netflix and Spring Cloud Consul).
Unresolved directive in <stdin> - include::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/docs/src/main/asciidoc/building.adoc[]
If you get an exception due to "Illegal key size" and you use Sun's JDK, you need to install the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files.
See the following links for more information:
* https://www.oracle.com/technetwork/java/javase/downloads/jce-6-download-429243.html[Java 6 JCE]
* https://www.oracle.com/technetwork/java/javase/downloads/jce-7-download-432124.html[Java 7 JCE]
* https://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html[Java 8 JCE]
Extract the files into the JDK/jre/lib/security folder for whichever version of JRE/JDK x64/x86 you use.
== Building
:jdkversion: 17
=== Basic Compile and Test
To build the source you will need to install JDK {jdkversion}.
Spring Cloud uses Maven for most build-related activities, and you
should be able to get off the ground quite quickly by cloning the
project you are interested in and typing
----
$ ./mvnw install
----
NOTE: You can also install Maven (>=3.3.3) yourself and run the `mvn` command
in place of `./mvnw` in the examples below. If you do that you also
might need to add `-P spring` if your local Maven settings do not
contain repository declarations for spring pre-release artifacts.
NOTE: Be aware that you might need to increase the amount of memory
available to Maven by setting a `MAVEN_OPTS` environment variable with
a value like `-Xmx512m -XX:MaxPermSize=128m`. We try to cover this in
the `.mvn` configuration, so if you find you have to do it to make a
build succeed, please raise a ticket to get the settings added to
source control.
The projects that require middleware (i.e. Redis) for testing generally
require that a local instance of [Docker](https://www.docker.com/get-started) is installed and running.
=== Documentation
The spring-cloud-build module has a "docs" profile, and if you switch
that on it will try to build asciidoc sources from
`src/main/asciidoc`. As part of that process it will look for a
`README.adoc` and process it by loading all the includes, but not
parsing or rendering it, just copying it to `${main.basedir}`
(defaults to `${basedir}`, i.e. the root of the project). If there are
any changes in the README it will then show up after a Maven build as
a modified file in the correct place. Just commit it and push the change.
=== Working with the code
If you don't have an IDE preference we would recommend that you use
https://www.springsource.com/developer/sts[Spring Tools Suite] or
https://eclipse.org[Eclipse] when working with the code. We use the
https://eclipse.org/m2e/[m2eclipse] eclipse plugin for maven support. Other IDEs and tools
should also work without issue as long as they use Maven 3.3.3 or better.
==== Activate the Spring Maven profile
Spring Cloud projects require the 'spring' Maven profile to be activated to resolve
the spring milestone and snapshot repositories. Use your preferred IDE to set this
profile to be active, or you may experience build errors.
==== Importing into eclipse with m2eclipse
We recommend the https://eclipse.org/m2e/[m2eclipse] eclipse plugin when working with
eclipse. If you don't already have m2eclipse installed it is available from the "eclipse
marketplace".
NOTE: Older versions of m2e do not support Maven 3.3, so once the
projects are imported into Eclipse you will also need to tell
m2eclipse to use the right profile for the projects. If you
see many different errors related to the POMs in the projects, check
that you have an up to date installation. If you can't upgrade m2e,
add the "spring" profile to your `settings.xml`. Alternatively you can
copy the repository settings from the "spring" profile of the parent
pom into your `settings.xml`.
==== Importing into eclipse without m2eclipse
If you prefer not to use m2eclipse you can generate eclipse project metadata using the
following command:
[indent=0]
----
$ ./mvnw eclipse:eclipse
----
The generated eclipse projects can be imported by selecting `import existing projects`
from the `file` menu.
== Contributing
:spring-cloud-build-branch: master
Spring Cloud is released under the non-restrictive Apache 2.0 license,
and follows a very standard Github development process, using Github
tracker for issues and merging pull requests into master. If you want
to contribute even something trivial please do not hesitate, but
follow the guidelines below.
=== Sign the Contributor License Agreement
Before we accept a non-trivial patch or pull request we will need you to sign the
https://cla.pivotal.io/sign/spring[Contributor License Agreement].
Signing the contributor's agreement does not grant anyone commit rights to the main
repository, but it does mean that we can accept your contributions, and you will get an
author credit if we do. Active contributors might be asked to join the core team, and
given the ability to merge pull requests.
=== Code of Conduct
This project adheres to the Contributor Covenant https://github.com/spring-cloud/spring-cloud-build/blob/master/docs/src/main/asciidoc/code-of-conduct.adoc[code of
conduct]. By participating, you are expected to uphold this code. Please report
unacceptable behavior to spring-code-of-conduct@pivotal.io.
=== Code Conventions and Housekeeping
None of these is essential for a pull request, but they will all help. They can also be
added after the original pull request but before a merge.
* Use the Spring Framework code format conventions. If you use Eclipse
you can import formatter settings using the
`eclipse-code-formatter.xml` file from the
https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/spring-cloud-dependencies-parent/eclipse-code-formatter.xml[Spring
Cloud Build] project. If using IntelliJ, you can use the
https://plugins.jetbrains.com/plugin/6546[Eclipse Code Formatter
Plugin] to import the same file.
* Make sure all new `.java` files to have a simple Javadoc class comment with at least an
`@author` tag identifying you, and preferably at least a paragraph on what the class is
for.
* Add the ASF license header comment to all new `.java` files (copy from existing files
in the project)
* Add yourself as an `@author` to the .java files that you modify substantially (more
than cosmetic changes).
* Add some Javadocs and, if you change the namespace, some XSD doc elements.
* A few unit tests would help a lot as well -- someone has to do it.
* If no-one else is using your branch, please rebase it against the current master (or
other target branch in the main project).
* When writing a commit message please follow https://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html[these conventions],
if you are fixing an existing issue please add `Fixes gh-XXXX` at the end of the commit
message (where XXXX is the issue number).
=== Checkstyle
Spring Cloud Build comes with a set of checkstyle rules. You can find them in the `spring-cloud-build-tools` module. The most notable files under the module are:
.spring-cloud-build-tools/
----
└── src
   ├── checkstyle
     └── checkstyle-suppressions.xml <3>
   └── main
   └── resources
   ├── checkstyle-header.txt <2>
   └── checkstyle.xml <1>
----
<1> Default Checkstyle rules
<2> File header setup
<3> Default suppression rules
==== Checkstyle configuration
Checkstyle rules are *disabled by default*. To add checkstyle to your project just define the following properties and plugins.
.pom.xml
----
<properties>
<maven-checkstyle-plugin.failsOnError>true</maven-checkstyle-plugin.failsOnError> <1>
<maven-checkstyle-plugin.failsOnViolation>true
</maven-checkstyle-plugin.failsOnViolation> <2>
<maven-checkstyle-plugin.includeTestSourceDirectory>true
</maven-checkstyle-plugin.includeTestSourceDirectory> <3>
</properties>
<build>
<plugins>
<plugin> <4>
<groupId>io.spring.javaformat</groupId>
<artifactId>spring-javaformat-maven-plugin</artifactId>
</plugin>
<plugin> <5>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
</plugin>
</plugins>
<reporting>
<plugins>
<plugin> <5>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-checkstyle-plugin</artifactId>
</plugin>
</plugins>
</reporting>
</build>
----
<1> Fails the build upon Checkstyle errors
<2> Fails the build upon Checkstyle violations
<3> Checkstyle analyzes also the test sources
<4> Add the Spring Java Format plugin that will reformat your code to pass most of the Checkstyle formatting rules
<5> Add checkstyle plugin to your build and reporting phases
If you need to suppress some rules (e.g. line length needs to be longer), then it's enough for you to define a file under `${project.root}/src/checkstyle/checkstyle-suppressions.xml` with your suppressions. Example:
.projectRoot/src/checkstyle/checkstyle-suppresions.xml
----
<?xml version="1.0"?>
<!DOCTYPE suppressions PUBLIC
"-//Puppy Crawl//DTD Suppressions 1.1//EN"
"https://www.puppycrawl.com/dtds/suppressions_1_1.dtd">
<suppressions>
<suppress files=".*ConfigServerApplication\.java" checks="HideUtilityClassConstructor"/>
<suppress files=".*ConfigClientWatch\.java" checks="LineLengthCheck"/>
</suppressions>
----
It's advisable to copy the `${spring-cloud-build.rootFolder}/.editorconfig` and `${spring-cloud-build.rootFolder}/.springformat` to your project. That way, some default formatting rules will be applied. You can do so by running this script:
```bash
$ curl https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/.editorconfig -o .editorconfig
$ touch .springformat
```
=== IDE setup
==== Intellij IDEA
In order to setup Intellij you should import our coding conventions, inspection profiles and set up the checkstyle plugin.
The following files can be found in the https://github.com/spring-cloud/spring-cloud-build/tree/master/spring-cloud-build-tools[Spring Cloud Build] project.
.spring-cloud-build-tools/
----
└── src
   ├── checkstyle
     └── checkstyle-suppressions.xml <3>
   └── main
   └── resources
   ├── checkstyle-header.txt <2>
   ├── checkstyle.xml <1>
   └── intellij
      ├── Intellij_Project_Defaults.xml <4>
      └── Intellij_Spring_Boot_Java_Conventions.xml <5>
----
<1> Default Checkstyle rules
<2> File header setup
<3> Default suppression rules
<4> Project defaults for Intellij that apply most of Checkstyle rules
<5> Project style conventions for Intellij that apply most of Checkstyle rules
.Code style
image::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/{spring-cloud-build-branch}/docs/src/main/asciidoc/images/intellij-code-style.png[Code style]
Go to `File` -> `Settings` -> `Editor` -> `Code style`. There click on the icon next to the `Scheme` section. There, click on the `Import Scheme` value and pick the `Intellij IDEA code style XML` option. Import the `spring-cloud-build-tools/src/main/resources/intellij/Intellij_Spring_Boot_Java_Conventions.xml` file.
.Inspection profiles
image::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/{spring-cloud-build-branch}/docs/src/main/asciidoc/images/intellij-inspections.png[Code style]
Go to `File` -> `Settings` -> `Editor` -> `Inspections`. There click on the icon next to the `Profile` section. There, click on the `Import Profile` and import the `spring-cloud-build-tools/src/main/resources/intellij/Intellij_Project_Defaults.xml` file.
.Checkstyle
To have Intellij work with Checkstyle, you have to install the `Checkstyle` plugin. It's advisable to also install the `Assertions2Assertj` to automatically convert the JUnit assertions
image::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/{spring-cloud-build-branch}/docs/src/main/asciidoc/images/intellij-checkstyle.png[Checkstyle]
Go to `File` -> `Settings` -> `Other settings` -> `Checkstyle`. There click on the `+` icon in the `Configuration file` section. There, you'll have to define where the checkstyle rules should be picked from. In the image above, we've picked the rules from the cloned Spring Cloud Build repository. However, you can point to the Spring Cloud Build's GitHub repository (e.g. for the `checkstyle.xml` : `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/spring-cloud-build-tools/src/main/resources/checkstyle.xml`). We need to provide the following variables:
- `checkstyle.header.file` - please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` URL.
- `checkstyle.suppressions.file` - default suppressions. Please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` URL.
- `checkstyle.additional.suppressions.file` - this variable corresponds to suppressions in your local project. E.g. you're working on `spring-cloud-contract`. Then point to the `project-root/src/checkstyle/checkstyle-suppressions.xml` folder. Example for `spring-cloud-contract` would be: `/home/username/spring-cloud-contract/src/checkstyle/checkstyle-suppressions.xml`.
IMPORTANT: Remember to set the `Scan Scope` to `All sources` since we apply checkstyle rules for production and test sources.
=== Duplicate Finder
Spring Cloud Build brings along the `basepom:duplicate-finder-maven-plugin`, that enables flagging duplicate and conflicting classes and resources on the java classpath.
==== Duplicate Finder configuration
Duplicate finder is *enabled by default* and will run in the `verify` phase of your Maven build, but it will only take effect in your project if you add the `duplicate-finder-maven-plugin` to the `build` section of the projecst's `pom.xml`.
.pom.xml
[source,xml]
----
<build>
<plugins>
<plugin>
<groupId>org.basepom.maven</groupId>
<artifactId>duplicate-finder-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
----
For other properties, we have set defaults as listed in the https://github.com/basepom/duplicate-finder-maven-plugin/wiki[plugin documentation].
You can easily override them but setting the value of the selected property prefixed with `duplicate-finder-maven-plugin`. For example, set `duplicate-finder-maven-plugin.skip` to `true` in order to skip duplicates check in your build.
If you need to add `ignoredClassPatterns` or `ignoredResourcePatterns` to your setup, make sure to add them in the plugin configuration section of your project:
[source,xml]
----
<build>
<plugins>
<plugin>
<groupId>org.basepom.maven</groupId>
<artifactId>duplicate-finder-maven-plugin</artifactId>
<configuration>
<ignoredClassPatterns>
<ignoredClassPattern>org.joda.time.base.BaseDateTime</ignoredClassPattern>
<ignoredClassPattern>.*module-info</ignoredClassPattern>
</ignoredClassPatterns>
<ignoredResourcePatterns>
<ignoredResourcePattern>changelog.txt</ignoredResourcePattern>
</ignoredResourcePatterns>
</configuration>
</plugin>
</plugins>
</build>
----
[[contributing]]
= Contributing
:page-section-summary-toc: 1
Unresolved directive in <stdin> - include::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/docs/src/main/asciidoc/contributing.adoc[]

38
docs/antora-playbook.yml

@ -0,0 +1,38 @@ @@ -0,0 +1,38 @@
antora:
extensions:
- '@springio/antora-extensions/partial-build-extension'
- require: '@springio/antora-extensions/latest-version-extension'
- require: '@springio/antora-extensions/inject-collector-cache-config-extension'
- '@antora/collector-extension'
- '@antora/atlas-extension'
- require: '@springio/antora-extensions/root-component-extension'
root_component_name: 'cloud-commons'
site:
title: Spring Cloud Commons
url: https://docs.spring.io/spring-cloud-commons/reference/
content:
sources:
- url: ./..
branches: HEAD
start_path: docs
worktrees: true
asciidoc:
attributes:
page-stackoverflow-url: https://stackoverflow.com/tags/spring-cloud
page-pagination: ''
hide-uri-scheme: '@'
tabs-sync-option: '@'
chomp: 'all'
extensions:
- '@asciidoctor/tabs'
- '@springio/asciidoctor-extensions'
sourcemap: true
urls:
latest_version_segment: ''
runtime:
log:
failure_level: warn
format: pretty
ui:
bundle:
url: https://github.com/spring-io/antora-ui-spring/releases/download/v0.3.4/ui-bundle.zip

12
docs/antora.yml

@ -0,0 +1,12 @@ @@ -0,0 +1,12 @@
name: cloud-commons
version: true
title: Spring Cloud Commons
nav:
- modules/ROOT/nav.adoc
ext:
collector:
run:
command: ./mvnw validate process-resources -Pdocs -pl docs
local: true
scan:
dir: ./target/classes/antora-resources/

11
docs/modules/ROOT/nav.adoc

@ -0,0 +1,11 @@ @@ -0,0 +1,11 @@
* xref:index.adoc[]
** xref:intro.adoc[]
** xref:spring-cloud-commons/application-context-services.adoc[]
** xref:spring-cloud-commons/common-abstractions.adoc[]
** xref:spring-cloud-commons/loadbalancer.adoc[]
** xref:spring-cloud-commons/cachedrandompropertysource.adoc[]
** xref:spring-cloud-commons/security.adoc[]
* xref:spring-cloud-circuitbreaker.adoc[]
* xref:appendix.adoc[]
** xref:configprops.adoc[]

12
docs/src/main/asciidoc/appendix.adoc → docs/modules/ROOT/pages/appendix.adoc

@ -1,9 +1,8 @@ @@ -1,9 +1,8 @@
:numbered!:
[appendix]
[[common-application-properties]]
== Common application properties
= Common application properties
include::_attributes.adoc[]
include::partial$_attributes.adoc[]
Various properties can be specified inside your `application.properties` file, inside your `application.yml` file, or as command line switches.
This appendix provides a list of common {project-full-name} properties and references to the underlying classes that consume them.
@ -11,6 +10,9 @@ This appendix provides a list of common {project-full-name} properties and refer @@ -11,6 +10,9 @@ This appendix provides a list of common {project-full-name} properties and refer
NOTE: Property contributions can come from additional jar files on your classpath, so you should not consider this an exhaustive list.
Also, you can define your own properties.
include::_configprops.adoc[]
[[observability]]
== Observability metadata
include::_observability.adoc[]
include::partial$_metrics.adoc[]
include::partial$_spans.adoc[]

6
docs/modules/ROOT/pages/configprops.adoc

@ -0,0 +1,6 @@ @@ -0,0 +1,6 @@
[[configuration-properties]]
= Configuration Properties
Below you can find a list of configuration properties.
include::partial$_configprops.adoc[]

9
docs/modules/ROOT/pages/index.adoc

@ -0,0 +1,9 @@ @@ -0,0 +1,9 @@
[[cloud-native-applications]]
= Cloud Native Applications
include::partial$_attributes.adoc[]
// TODO: figure out remote includes in docs and replace pasted text
// include::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/docs/src/main/asciidoc/contributing-docs.adoc[]
NOTE: Spring Cloud is released under the non-restrictive Apache 2.0 license.
If you would like to contribute to this section of the documentation or if you find an error, you can find the source code and issue trackers for the project at {github-issues}[github].

3
docs/src/main/asciidoc/intro.adoc → docs/modules/ROOT/pages/intro.adoc

@ -1,3 +1,5 @@ @@ -1,3 +1,5 @@
[[introduction]]
= Introduction
https://pivotal.io/platform-as-a-service/migrating-to-cloud-native-application-architectures-ebook[Cloud Native] is a style of application development that encourages easy adoption of best practices in the areas of continuous delivery and value-driven development.
A related discipline is that of building https://12factor.net/[12-factor Applications], in which development practices are aligned with delivery and operations goals -- for instance, by using declarative programming and management and monitoring.
@ -7,4 +9,3 @@ Spring Cloud facilitates these styles of development in a number of specific way @@ -7,4 +9,3 @@ Spring Cloud facilitates these styles of development in a number of specific way
Many of those features are covered by https://projects.spring.io/spring-boot[Spring Boot], on which Spring Cloud builds. Some more features are delivered by Spring Cloud as two libraries: Spring Cloud Context and Spring Cloud Commons.
Spring Cloud Context provides utilities and special services for the `ApplicationContext` of a Spring Cloud application (bootstrap context, encryption, refresh scope, and environment endpoints). Spring Cloud Commons is a set of abstractions and common classes used in different Spring Cloud implementations (such as Spring Cloud Netflix and Spring Cloud Consul).
include::jce.adoc[]

15
docs/src/main/asciidoc/spring-cloud-circuitbreaker.adoc → docs/modules/ROOT/pages/spring-cloud-circuitbreaker.adoc

@ -1,9 +1,11 @@ @@ -1,9 +1,11 @@
== Introduction
[[introduction]]
= Spring Cloud Circuit Breaker
Spring Cloud Circuit breaker provides an abstraction across different circuit breaker implementations.
It provides a consistent API to use in your applications, letting you, the developer, choose the circuit breaker implementation that best fits your needs for your application.
=== Supported Implementations
[[supported-implementations]]
== Supported Implementations
Spring Cloud supports the following circuit-breaker implementations:
@ -11,12 +13,12 @@ Spring Cloud supports the following circuit-breaker implementations: @@ -11,12 +13,12 @@ Spring Cloud supports the following circuit-breaker implementations:
* https://github.com/alibaba/Sentinel[Sentinel]
* https://github.com/spring-projects/spring-retry[Spring Retry]
[[core-concepts]]
== Core Concepts
To create a circuit breaker in your code, you can use the `CircuitBreakerFactory` API. When you include a Spring Cloud Circuit Breaker starter on your classpath, a bean that implements this API is automatically created for you.
The following example shows a simple example of how to use this API:
====
[source,java]
----
@Service
@ -35,7 +37,6 @@ public static class DemoControllerService { @@ -35,7 +37,6 @@ public static class DemoControllerService {
}
----
====
The `CircuitBreakerFactory.create` API creates an instance of a class called `CircuitBreaker`.
The `run` method takes a `Supplier` and a `Function`.
@ -44,12 +45,12 @@ The `Function` is the fallback that is run if the circuit breaker is tripped. @@ -44,12 +45,12 @@ The `Function` is the fallback that is run if the circuit breaker is tripped.
The function is passed the `Throwable` that caused the fallback to be triggered.
You can optionally exclude the fallback if you do not want to provide one.
[[circuit-breakers-in-reactive-code]]
=== Circuit Breakers In Reactive Code
If Project Reactor is on the class path, you can also use `ReactiveCircuitBreakerFactory` for your reactive code.
The following example shows how to do so:
====
[source,java]
----
@Service
@ -69,13 +70,13 @@ public static class DemoControllerService { @@ -69,13 +70,13 @@ public static class DemoControllerService {
}
}
----
====
The `ReactiveCircuitBreakerFactory.create` API creates an instance of a class called `ReactiveCircuitBreaker`.
The `run` method takes a `Mono` or a `Flux` and wraps it in a circuit breaker.
You can optionally profile a fallback `Function`, which will be called if the circuit breaker is tripped and is passed the `Throwable`
that caused the failure.
[[configuration]]
== Configuration
You can configure your circuit breakers by creating beans of type `Customizer`.
@ -94,7 +95,6 @@ for example, in case of https://resilience4j.readme.io/docs/circuitbreaker#secti @@ -94,7 +95,6 @@ for example, in case of https://resilience4j.readme.io/docs/circuitbreaker#secti
The following example shows the way for each `io.github.resilience4j.circuitbreaker.CircuitBreaker` to consume events.
====
[source,java]
----
Customizer.once(circuitBreaker -> {
@ -102,4 +102,3 @@ Customizer.once(circuitBreaker -> { @@ -102,4 +102,3 @@ Customizer.once(circuitBreaker -> {
.onStateTransition(event -> log.info("{}: {}", event.getCircuitBreakerName(), event.getStateTransition()));
}, CircuitBreaker::getName)
----
====

254
docs/modules/ROOT/pages/spring-cloud-commons/application-context-services.adoc

@ -0,0 +1,254 @@ @@ -0,0 +1,254 @@
[[spring-cloud-context-application-context-services]]
= Spring Cloud Context: Application Context Services
Spring Boot has an opinionated view of how to build an application with Spring.
For instance, it has conventional locations for common configuration files and has endpoints for common management and monitoring tasks.
Spring Cloud builds on top of that and adds a few features that many components in a system would use or occasionally need.
[[the-bootstrap-application-context]]
== The Bootstrap Application Context
A Spring Cloud application operates by creating a "`bootstrap`" context, which is a parent context for the main application.
This context is responsible for loading configuration properties from the external sources and for decrypting properties in the local external configuration files.
The two contexts share an `Environment`, which is the source of external properties for any Spring application.
By default, bootstrap properties (not `bootstrap.properties` but properties that are loaded during the bootstrap phase) are added with high precedence, so they cannot be overridden by local configuration.
The bootstrap context uses a different convention for locating external configuration than the main application context.
Instead of `application.yml` (or `.properties`), you can use `bootstrap.yml`, keeping the external configuration for bootstrap and main context nicely separate.
The following listing shows an example:
.bootstrap.yml
----
spring:
application:
name: foo
cloud:
config:
uri: ${SPRING_CONFIG_URI:http://localhost:8888}
----
If your application needs any application-specific configuration from the server, it is a good idea to set the `spring.application.name` (in `bootstrap.yml` or `application.yml`).
For the property `spring.application.name` to be used as the application's context ID, you must set it in `bootstrap.[properties | yml]`.
If you want to retrieve specific profile configuration, you should also set `spring.profiles.active` in `bootstrap.[properties | yml]`.
You can disable the bootstrap process completely by setting `spring.cloud.bootstrap.enabled=false` (for example, in system properties).
[[application-context-hierarchies]]
== Application Context Hierarchies
If you build an application context from `SpringApplication` or `SpringApplicationBuilder`, the Bootstrap context is added as a parent to that context.
It is a feature of Spring that child contexts inherit property sources and profiles from their parent, so the "`main`" application context contains additional property sources, compared to building the same context without Spring Cloud Config.
The additional property sources are:
* "`bootstrap`": If any `PropertySourceLocators` are found in the bootstrap context and if they have non-empty properties, an optional `CompositePropertySource` appears with high priority.
An example would be properties from the Spring Cloud Config Server.
See "`xref:spring-cloud-commons/application-context-services.adoc#customizing-bootstrap-property-sources[Customizing the Bootstrap Property Sources]`" for how to customize the contents of this property source.
NOTE: Prior to Spring Cloud 2022.0.3 `PropertySourceLocators` (including the ones for Spring Cloud Config) were run during
the main application context and not in the Bootstrap context. You can force `PropertySourceLocators` to be run during the
Bootstrap context by setting `spring.cloud.config.initialize-on-context-refresh=true` in `bootstrap.[properties | yaml]`.
* "`applicationConfig: [classpath:bootstrap.yml]`" (and related files if Spring profiles are active): If you have a `bootstrap.yml` (or `.properties`), those properties are used to configure the bootstrap context.
Then they get added to the child context when its parent is set.
They have lower precedence than the `application.yml` (or `.properties`) and any other property sources that are added to the child as a normal part of the process of creating a Spring Boot application.
See "`xref:spring-cloud-commons/application-context-services.adoc#customizing-bootstrap-properties[Changing the Location of Bootstrap Properties]`" for how to customize the contents of these property sources.
Because of the ordering rules of property sources, the "`bootstrap`" entries take precedence.
However, note that these do not contain any data from `bootstrap.yml`, which has very low precedence but can be used to set defaults.
You can extend the context hierarchy by setting the parent context of any `ApplicationContext` you create -- for example, by using its own interface or with the `SpringApplicationBuilder` convenience methods (`parent()`, `child()` and `sibling()`).
The bootstrap context is the parent of the most senior ancestor that you create yourself.
Every context in the hierarchy has its own "`bootstrap`" (possibly empty) property source to avoid promoting values inadvertently from parents down to their descendants.
If there is a config server, every context in the hierarchy can also (in principle) have a different `spring.application.name` and, hence, a different remote property source.
Normal Spring application context behavior rules apply to property resolution: properties from a child context override those in
the parent, by name and also by property source name.
(If the child has a property source with the same name as the parent, the value from the parent is not included in the child).
Note that the `SpringApplicationBuilder` lets you share an `Environment` amongst the whole hierarchy, but that is not the default.
Thus, sibling contexts (in particular) do not need to have the same profiles or property sources, even though they may share common values with their parent.
[[customizing-bootstrap-properties]]
== Changing the Location of Bootstrap Properties
The `bootstrap.yml` (or `.properties`) location can be specified by setting `spring.cloud.bootstrap.name` (default: `bootstrap`), `spring.cloud.bootstrap.location` (default: empty) or `spring.cloud.bootstrap.additional-location` (default: empty) -- for example, in System properties.
Those properties behave like the `spring.config.*` variants with the same name.
With `spring.cloud.bootstrap.location` the default locations are replaced and only the specified ones are used.
To add locations to the list of default ones, `spring.cloud.bootstrap.additional-location` can be used.
In fact, they are used to set up the bootstrap `ApplicationContext` by setting those properties in its `Environment`.
If there is an active profile (from `spring.profiles.active` or through the `Environment` API in the context you are building), properties in that profile get loaded as well, the same as in a regular Spring Boot app -- for example, from `bootstrap-development.properties` for a `development` profile.
[[overriding-bootstrap-properties]]
== Overriding the Values of Remote Properties
The property sources that are added to your application by the bootstrap context are often "`remote`" (from example, from Spring Cloud Config Server).
By default, they cannot be overridden locally.
If you want to let your applications override the remote properties with their own system properties or config files, the remote property source has to grant it permission by setting `spring.cloud.config.allowOverride=true` (it does not work to set this locally).
Once that flag is set, two finer-grained settings control the location of the remote properties in relation to system properties and the application's local configuration:
* `spring.cloud.config.overrideNone=true`: Override from any local property source.
* `spring.cloud.config.overrideSystemProperties=false`: Only system properties, command line arguments, and environment variables (but not the local config files) should override the remote settings.
[[customizing-the-bootstrap-configuration]]
== Customizing the Bootstrap Configuration
The bootstrap context can be set to do anything you like by adding entries to `/META-INF/spring.factories` under a key named `org.springframework.cloud.bootstrap.BootstrapConfiguration`.
This holds a comma-separated list of Spring `@Configuration` classes that are used to create the context.
Any beans that you want to be available to the main application context for autowiring can be created here.
There is a special contract for `@Beans` of type `ApplicationContextInitializer`.
If you want to control the startup sequence, you can mark classes with the `@Order` annotation (the default order is `last`).
WARNING: When adding custom `BootstrapConfiguration`, be careful that the classes you add are not `@ComponentScanned` by mistake into your "`main`" application context, where they might not be needed.
Use a separate package name for boot configuration classes and make sure that name is not already covered by your `@ComponentScan` or `@SpringBootApplication` annotated configuration classes.
The bootstrap process ends by injecting initializers into the main `SpringApplication` instance (which is the normal Spring Boot startup sequence, whether it runs as a standalone application or is deployed in an application server).
First, a bootstrap context is created from the classes found in `spring.factories`.
Then, all `@Beans` of type `ApplicationContextInitializer` are added to the main `SpringApplication` before it is started.
[[customizing-bootstrap-property-sources]]
== Customizing the Bootstrap Property Sources
The default property source for external configuration added by the bootstrap process is the Spring Cloud Config Server, but you can add additional sources by adding beans of type `PropertySourceLocator` to the bootstrap context (through `spring.factories`).
For instance, you can insert additional properties from a different server or from a database.
As an example, consider the following custom locator:
[source,java]
----
@Configuration
public class CustomPropertySourceLocator implements PropertySourceLocator {
@Override
public PropertySource<?> locate(Environment environment) {
return new MapPropertySource("customProperty",
Collections.<String, Object>singletonMap("property.from.sample.custom.source", "worked as intended"));
}
}
----
The `Environment` that is passed in is the one for the `ApplicationContext` about to be created -- in other words, the one for which we supply additional property sources.
It already has its normal Spring Boot-provided property sources, so you can use those to locate a property source specific to this `Environment` (for example, by keying it on `spring.application.name`, as is done in the default Spring Cloud Config Server property source locator).
If you create a jar with this class in it and then add a `META-INF/spring.factories` containing the following setting, the `customProperty` `PropertySource` appears in any application that includes that jar on its classpath:
[source]
----
org.springframework.cloud.bootstrap.BootstrapConfiguration=sample.custom.CustomPropertySourceLocator
----
As of Spring Cloud 2022.0.3, Spring Cloud will now call `PropertySourceLocators` twice. The first fetch
will retrieve any property sources without any profiles. These property sources will have the opportunity to
activate profiles using `spring.profiles.active`. After the main application context starts `PropertySourceLocators`
will be called a second time, this time with any active profiles allowing `PropertySourceLocators` to locate
any additional `PropertySources` with profiles.
[[logging-configuration]]
== Logging Configuration
If you use Spring Boot to configure log settings, you should place this configuration in `bootstrap.[yml | properties]` if you would like it to apply to all events.
NOTE: For Spring Cloud to initialize logging configuration properly, you cannot use a custom prefix.
For example, using `custom.loggin.logpath` is not recognized by Spring Cloud when initializing the logging system.
[[environment-changes]]
== Environment Changes
The application listens for an `EnvironmentChangeEvent` and reacts to the change in a couple of standard ways (additional `ApplicationListeners` can be added as `@Beans` in the normal way).
When an `EnvironmentChangeEvent` is observed, it has a list of key values that have changed, and the application uses those to:
* Re-bind any `@ConfigurationProperties` beans in the context.
* Set the logger levels for any properties in `logging.level.*`.
Note that the Spring Cloud Config Client does not, by default, poll for changes in the `Environment`.
Generally, we would not recommend that approach for detecting changes (although you can set it up with a
`@Scheduled` annotation).
If you have a scaled-out client application, it is better to broadcast the `EnvironmentChangeEvent` to all the instances instead of having them polling for changes (for example, by using the https://github.com/spring-cloud/spring-cloud-bus[Spring Cloud Bus]).
The `EnvironmentChangeEvent` covers a large class of refresh use cases, as long as you can actually make a change to the `Environment` and publish the event.
Note that those APIs are public and part of core Spring).
You can verify that the changes are bound to `@ConfigurationProperties` beans by visiting the `/configprops` endpoint (a standard Spring Boot Actuator feature).
For instance, a `DataSource` can have its `maxPoolSize` changed at runtime (the default `DataSource` created by Spring Boot is a `@ConfigurationProperties` bean) and grow capacity dynamically.
Re-binding `@ConfigurationProperties` does not cover another large class of use cases, where you need more control over the refresh and where you need a change to be atomic over the whole `ApplicationContext`.
To address those concerns, we have `@RefreshScope`.
[[refresh-scope]]
== Refresh Scope
When there is a configuration change, a Spring `@Bean` that is marked as `@RefreshScope` gets special treatment.
This feature addresses the problem of stateful beans that get their configuration injected only when they are initialized.
For instance, if a `DataSource` has open connections when the database URL is changed through the `Environment`, you probably want the holders of those connections to be able to complete what they are doing.
Then, the next time something borrows a connection from the pool, it gets one with the new URL.
Sometimes, it might even be mandatory to apply the `@RefreshScope` annotation on some beans that can be only initialized once.
If a bean is "`immutable`", you have to either annotate the bean with `@RefreshScope` or specify the classname under the property key: `spring.cloud.refresh.extra-refreshable`.
WARNING: If you hava a `DataSource` bean that is a `HikariDataSource`, it can not be
refreshed. It is the default value for `spring.cloud.refresh.never-refreshable`. Choose a
different `DataSource` implementation if you need it to be refreshed.
Refresh scope beans are lazy proxies that initialize when they are used (that is, when a method is called), and the scope acts as a cache of initialized values.
To force a bean to re-initialize on the next method call, you must invalidate its cache entry.
The `RefreshScope` is a bean in the context and has a public `refreshAll()` method to refresh all beans in the scope by clearing the target cache.
The `/refresh` endpoint exposes this functionality (over HTTP or JMX).
To refresh an individual bean by name, there is also a `refresh(String)` method.
To expose the `/refresh` endpoint, you need to add following configuration to your application:
[source,yaml]
----
management:
endpoints:
web:
exposure:
include: refresh
----
NOTE: `@RefreshScope` works (technically) on a `@Configuration` class, but it might lead to surprising behavior.
For example, it does not mean that all the `@Beans` defined in that class are themselves in `@RefreshScope`.
Specifically, anything that depends on those beans cannot rely on them being updated when a refresh is initiated, unless it is itself in `@RefreshScope`.
In that case, it is rebuilt on a refresh and its dependencies are re-injected.
At that point, they are re-initialized from the refreshed `@Configuration`).
NOTE: Removing a configuration value and then performing a refresh will not update the presence of the configuration value.
The configuration property must be present in order to update the value after a refresh. If you are relying on the presence of
a value in your application you might want to switch your logic to rely on its absence instead. Another option would be to rely
on the value changing rather than not being present in the application's configuration.
[[encryption-and-decryption]]
== Encryption and Decryption
Spring Cloud has an `Environment` pre-processor for decrypting property values locally.
It follows the same rules as the Spring Cloud Config Server and has the same external configuration through `encrypt.\*`.
Thus, you can use encrypted values in the form of `\{cipher}*`, and, as long as there is a valid key, they are decrypted before the main application context gets the `Environment` settings.
To use the encryption features in an application, you need to include Spring Security RSA in your classpath (Maven co-ordinates: `org.springframework.security:spring-security-rsa`), and you also need the full strength JCE extensions in your JVM.
If you get an exception due to "Illegal key size" and you use Sun's JDK, you need to install the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files.
See the following links for more information:
* https://www.oracle.com/technetwork/java/javase/downloads/jce-6-download-429243.html[Java 6 JCE]
* https://www.oracle.com/technetwork/java/javase/downloads/jce-7-download-432124.html[Java 7 JCE]
* https://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html[Java 8 JCE]
Extract the files into the JDK/jre/lib/security folder for whichever version of JRE/JDK x64/x86 you use.
[[endpoints]]
== Endpoints
For a Spring Boot Actuator application, some additional management endpoints are available. You can use:
* `POST` to `/actuator/env` to update the `Environment` and rebind `@ConfigurationProperties` and log levels.
To enabled this endpoint you must set `management.endpoint.env.post.enabled=true`.
* `/actuator/refresh` to re-load the boot strap context and refresh the `@RefreshScope` beans.
* `/actuator/restart` to close the `ApplicationContext` and restart it (disabled by default).
* `/actuator/pause` and `/actuator/resume` for calling the `Lifecycle` methods (`stop()` and `start()` on the `ApplicationContext`).
NOTE: While enabling the `POST` method for `/actuator/env` endpoint can provide flexibility and convenience in managing your application environment variables,
it's critical to ensure that the endpoint is secured and monitored to prevent potential security risks.
Add a `spring-boot-starter-security` dependency to configure access control for the actuator’s endpoint.
NOTE: If you disable the `/actuator/restart` endpoint then the `/actuator/pause` and `/actuator/resume` endpoints
will also be disabled since they are just a special case of `/actuator/restart`.

15
docs/modules/ROOT/pages/spring-cloud-commons/cachedrandompropertysource.adoc

@ -0,0 +1,15 @@ @@ -0,0 +1,15 @@
[[cachedrandompropertysource]]
= CachedRandomPropertySource
:page-section-summary-toc: 1
Spring Cloud Context provides a `PropertySource` that caches random values based on a key. Outside of the caching
functionality it works the same as Spring Boot's https://github.com/spring-projects/spring-boot/blob/main/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/env/RandomValuePropertySource.java[`RandomValuePropertySource`].
This random value might be useful in the case where you want a random value that is consistent even after the Spring Application
context restarts. The property value takes the form of `cachedrandom.[yourkey].[type]` where `yourkey` is the key in the cache. The `type` value can
be any type supported by Spring Boot's `RandomValuePropertySource`.
[source,properties,indent=0]
----
myrandom=${cachedrandom.appname.value}
----

595
docs/modules/ROOT/pages/spring-cloud-commons/common-abstractions.adoc

@ -0,0 +1,595 @@ @@ -0,0 +1,595 @@
[[spring-cloud-common-abstractions]]
= Spring Cloud Commons: Common Abstractions
Patterns such as service discovery, load balancing, and circuit breakers lend themselves to a common abstraction layer that can be consumed by all Spring Cloud clients, independent of the implementation (for example, discovery with Eureka or Consul).
[[discovery-client]]
== The `@EnableDiscoveryClient` Annotation
Spring Cloud Commons provides the `@EnableDiscoveryClient` annotation.
This looks for implementations of the `DiscoveryClient` and `ReactiveDiscoveryClient` interfaces with `META-INF/spring.factories`.
Implementations of the discovery client add a configuration class to `spring.factories` under the `org.springframework.cloud.client.discovery.EnableDiscoveryClient` key.
Examples of `DiscoveryClient` implementations include https://cloud.spring.io/spring-cloud-netflix/[Spring Cloud Netflix Eureka], https://cloud.spring.io/spring-cloud-consul/[Spring Cloud Consul Discovery], and https://cloud.spring.io/spring-cloud-zookeeper/[Spring Cloud Zookeeper Discovery].
Spring Cloud will provide both the blocking and reactive service discovery clients by default.
You can disable the blocking and/or reactive clients easily by setting `spring.cloud.discovery.blocking.enabled=false` or `spring.cloud.discovery.reactive.enabled=false`.
To completely disable service discovery you just need to set `spring.cloud.discovery.enabled=false`.
By default, implementations of `DiscoveryClient` auto-register the local Spring Boot server with the remote discovery server.
This behavior can be disabled by setting `autoRegister=false` in `@EnableDiscoveryClient`.
NOTE: `@EnableDiscoveryClient` is no longer required.
You can put a `DiscoveryClient` implementation on the classpath to cause the Spring Boot application to register with the service discovery server.
[[health-indicators]]
=== Health Indicators
Commons auto-configures the following Spring Boot health indicators.
[[discoveryclienthealthindicator]]
==== DiscoveryClientHealthIndicator
This health indicator is based on the currently registered `DiscoveryClient` implementation.
* To disable entirely, set `spring.cloud.discovery.client.health-indicator.enabled=false`.
* To disable the description field, set `spring.cloud.discovery.client.health-indicator.include-description=false`.
Otherwise, it can bubble up as the `description` of the rolled up `HealthIndicator`.
* To disable service retrieval, set `spring.cloud.discovery.client.health-indicator.use-services-query=false`.
By default, the indicator invokes the client's `getServices` method. In deployments with many registered services it may too
costly to retrieve all services during every check. This will skip the service retrieval and instead use the client's `probe` method.
[[discoverycompositehealthcontributor]]
==== DiscoveryCompositeHealthContributor
This composite health indicator is based on all registered `DiscoveryHealthIndicator` beans. To disable,
set `spring.cloud.discovery.client.composite-indicator.enabled=false`.
[[ordering-discoveryclient-instances]]
=== Ordering `DiscoveryClient` instances
`DiscoveryClient` interface extends `Ordered`. This is useful when using multiple discovery
clients, as it allows you to define the order of the returned discovery clients, similar to
how you can order the beans loaded by a Spring application. By default, the order of any `DiscoveryClient` is set to
`0`. If you want to set a different order for your custom `DiscoveryClient` implementations, you just need to override
the `getOrder()` method so that it returns the value that is suitable for your setup. Apart from this, you can use
properties to set the order of the `DiscoveryClient`
implementations provided by Spring Cloud, among others `ConsulDiscoveryClient`, `EurekaDiscoveryClient` and
`ZookeeperDiscoveryClient`. In order to do it, you just need to set the
`spring.cloud.\{clientIdentifier}.discovery.order` (or `eureka.client.order` for Eureka) property to the desired value.
[[simplediscoveryclient]]
=== SimpleDiscoveryClient
If there is no Service-Registry-backed `DiscoveryClient` in the classpath, `SimpleDiscoveryClient`
instance, that uses properties to get information on service and instances, will be used.
The information about the available instances should be passed to via properties in the following format:
`spring.cloud.discovery.client.simple.instances.service1[0].uri=http://s11:8080`, where
`spring.cloud.discovery.client.simple.instances` is the common prefix, then `service1` stands
for the ID of the service in question, while `[0]` indicates the index number of the instance
(as visible in the example, indexes start with `0`), and then the value of `uri` is
the actual URI under which the instance is available.
[[serviceregistry]]
== ServiceRegistry
Commons now provides a `ServiceRegistry` interface that provides methods such as `register(Registration)` and `deregister(Registration)`, which let you provide custom registered services.
`Registration` is a marker interface.
The following example shows the `ServiceRegistry` in use:
[source,java,indent=0]
----
@Configuration
@EnableDiscoveryClient(autoRegister=false)
public class MyConfiguration {
private ServiceRegistry registry;
public MyConfiguration(ServiceRegistry registry) {
this.registry = registry;
}
// called through some external process, such as an event or a custom actuator endpoint
public void register() {
Registration registration = constructRegistration();
this.registry.register(registration);
}
}
----
Each `ServiceRegistry` implementation has its own `Registry` implementation.
* `ZookeeperRegistration` used with `ZookeeperServiceRegistry`
* `EurekaRegistration` used with `EurekaServiceRegistry`
* `ConsulRegistration` used with `ConsulServiceRegistry`
If you are using the `ServiceRegistry` interface, you are going to need to pass the
correct `Registry` implementation for the `ServiceRegistry` implementation you
are using.
[[serviceregistry-auto-registration]]
=== ServiceRegistry Auto-Registration
By default, the `ServiceRegistry` implementation auto-registers the running service.
To disable that behavior, you can set:
* `@EnableDiscoveryClient(autoRegister=false)` to permanently disable auto-registration.
* `spring.cloud.service-registry.auto-registration.enabled=false` to disable the behavior through configuration.
[[serviceregistry-auto-registration-events]]
==== ServiceRegistry Auto-Registration Events
There are two events that will be fired when a service auto-registers. The first event, called
`InstancePreRegisteredEvent`, is fired before the service is registered. The second
event, called `InstanceRegisteredEvent`, is fired after the service is registered. You can register an
`ApplicationListener`(s) to listen to and react to these events.
NOTE: These events will not be fired if the `spring.cloud.service-registry.auto-registration.enabled` property is set to `false`.
[[service-registry-actuator-endpoint]]
=== Service Registry Actuator Endpoint
Spring Cloud Commons provides a `/service-registry` actuator endpoint.
This endpoint relies on a `Registration` bean in the Spring Application Context.
Calling `/service-registry` with GET returns the status of the `Registration`.
Using POST to the same endpoint with a JSON body changes the status of the current `Registration` to the new value.
The JSON body has to include the `status` field with the preferred value.
Please see the documentation of the `ServiceRegistry` implementation you use for the allowed values when updating the status and the values returned for the status.
For instance, Eureka's supported statuses are `UP`, `DOWN`, `OUT_OF_SERVICE`, and `UNKNOWN`.
[[rest-template-loadbalancer-client]]
== Spring RestTemplate as a Load Balancer Client
You can configure a `RestTemplate` to use a Load-balancer client.
To create a load-balanced `RestTemplate`, create a `RestTemplate` `@Bean` and use the `@LoadBalanced` qualifier, as the following example shows:
[source,java,indent=0]
----
@Configuration
public class MyConfiguration {
@LoadBalanced
@Bean
RestTemplate restTemplate() {
return new RestTemplate();
}
}
public class MyClass {
@Autowired
private RestTemplate restTemplate;
public String doOtherStuff() {
String results = restTemplate.getForObject("http://stores/stores", String.class);
return results;
}
}
----
CAUTION: A `RestTemplate` bean is no longer created through auto-configuration.
Individual applications must create it.
The URI needs to use a virtual host name (that is, a service name, not a host name).
The BlockingLoadBalancerClient is used to create a full physical address.
IMPORTANT: To use a load-balanced `RestTemplate`, you need to have a load-balancer implementation in your classpath.
Add xref:spring-cloud-commons/loadbalancer.adoc#spring-cloud-loadbalancer-starter[Spring Cloud LoadBalancer starter] to your project in order to use it.
[[webclinet-loadbalancer-client]]
== Spring WebClient as a Load Balancer Client
You can configure `WebClient` to automatically use a load-balancer client.
To create a load-balanced `WebClient`, create a `WebClient.Builder` `@Bean` and use the `@LoadBalanced` qualifier, as follows:
[source,java,indent=0]
----
@Configuration
public class MyConfiguration {
@Bean
@LoadBalanced
public WebClient.Builder loadBalancedWebClientBuilder() {
return WebClient.builder();
}
}
public class MyClass {
@Autowired
private WebClient.Builder webClientBuilder;
public Mono<String> doOtherStuff() {
return webClientBuilder.build().get().uri("http://stores/stores")
.retrieve().bodyToMono(String.class);
}
}
----
The URI needs to use a virtual host name (that is, a service name, not a host name).
The Spring Cloud LoadBalancer is used to create a full physical address.
IMPORTANT: If you want to use a `@LoadBalanced WebClient.Builder`, you need to have a load balancer
implementation in the classpath. We recommend that you add the
xref:spring-cloud-commons/loadbalancer.adoc#spring-cloud-loadbalancer-starter[Spring Cloud LoadBalancer starter] to your project.
Then, `ReactiveLoadBalancer` is used underneath.
[[retrying-failed-requests]]
=== Retrying Failed Requests
A load-balanced `RestTemplate` can be configured to retry failed requests.
By default, this logic is disabled.
For the non-reactive version (with `RestTemplate`), you can enable it by adding link:https://github.com/spring-projects/spring-retry[Spring Retry] to your application's classpath. For the reactive version (with `WebTestClient`), you need to set `spring.cloud.loadbalancer.retry.enabled=true`.
If you would like to disable the retry logic with Spring Retry or Reactive Retry on the classpath, you can set `spring.cloud.loadbalancer.retry.enabled=false`.
For the non-reactive implementation, if you would like to implement a `BackOffPolicy` in your retries, you need to create a bean of type `LoadBalancedRetryFactory` and override the `createBackOffPolicy()` method.
For the reactive implementation, you just need to enable it by setting `spring.cloud.loadbalancer.retry.backoff.enabled` to `false`.
You can set:
- `spring.cloud.loadbalancer.retry.maxRetriesOnSameServiceInstance` - indicates how many times a request should be retried on the same `ServiceInstance` (counted separately for every selected instance)
- `spring.cloud.loadbalancer.retry.maxRetriesOnNextServiceInstance` - indicates how many times a request should be retried a newly selected `ServiceInstance`
- `spring.cloud.loadbalancer.retry.retryableStatusCodes` - the status codes on which to always retry a failed request.
For the reactive implementation, you can additionally set:
- `spring.cloud.loadbalancer.retry.backoff.minBackoff` - Sets the minimum backoff duration (by default, 5 milliseconds)
- `spring.cloud.loadbalancer.retry.backoff.maxBackoff` - Sets the maximum backoff duration (by default, max long value of milliseconds)
- `spring.cloud.loadbalancer.retry.backoff.jitter` - Sets the jitter used for calculating the actual backoff duration for each call (by default, 0.5).
For the reactive implementation, you can also implement your own `LoadBalancerRetryPolicy` to have more detailed control over the load-balanced call retries.
For both implementations, you can also set the exceptions that trigger the replies by adding a list of values under the `spring.cloud.loadbalancer.[serviceId].retry.retryable-exceptions` property. If you do, we make sure to add `RetryableStatusCodeExceptions` to the list of exceptions provided by you, so that we also retry on retryable status codes. If you do not specify any exceptions via properties, the exceptions we use by default are `IOException`, `TimeoutException` and `RetryableStatusCodeException`. You can also enable retrying on all exceptions by setting `spring.cloud.loadbalancer.[serviceId].retry.retry-on-all-exceptions` to `true`.
WARNING: If you use the blocking implementation with Spring Retries, if you want to keep the behaviour from previous releases, set `spring.cloud.loadbalancer.[serviceId].retry.retry-on-all-exceptions` to `true` as that used to be the default mode for the blocking implementation.
NOTE: Individual Loadbalancer clients may be configured individually with the same properties as above except the prefix is `spring.cloud.loadbalancer.clients.<clientId>.*` where `clientId` is the name of the loadbalancer.
NOTE: For load-balanced retries, by default, we wrap the `ServiceInstanceListSupplier` bean with `RetryAwareServiceInstanceListSupplier` to select a different instance from the one previously chosen, if available. You can disable this behavior by setting the value of `spring.cloud.loadbalancer.retry.avoidPreviousInstance` to `false`.
[source,java,indent=0]
----
@Configuration
public class MyConfiguration {
@Bean
LoadBalancedRetryFactory retryFactory() {
return new LoadBalancedRetryFactory() {
@Override
public BackOffPolicy createBackOffPolicy(String service) {
return new ExponentialBackOffPolicy();
}
};
}
}
----
If you want to add one or more `RetryListener` implementations to your retry functionality, you need to
create a bean of type `LoadBalancedRetryListenerFactory` and return the `RetryListener` array
you would like to use for a given service, as the following example shows:
[source,java,indent=0]
----
@Configuration
public class MyConfiguration {
@Bean
LoadBalancedRetryListenerFactory retryListenerFactory() {
return new LoadBalancedRetryListenerFactory() {
@Override
public RetryListener[] createRetryListeners(String service) {
return new RetryListener[]{new RetryListener() {
@Override
public <T, E extends Throwable> boolean open(RetryContext context, RetryCallback<T, E> callback) {
//TODO Do you business...
return true;
}
@Override
public <T, E extends Throwable> void close(RetryContext context, RetryCallback<T, E> callback, Throwable throwable) {
//TODO Do you business...
}
@Override
public <T, E extends Throwable> void onError(RetryContext context, RetryCallback<T, E> callback, Throwable throwable) {
//TODO Do you business...
}
}};
}
};
}
}
----
[[multiple-resttemplate-objects]]
== Multiple `RestTemplate` Objects
If you want a `RestTemplate` that is not load-balanced, create a `RestTemplate` bean and inject it.
To access the load-balanced `RestTemplate`, use the `@LoadBalanced` qualifier when you create your `@Bean`, as the following example shows:
[source,java,indent=0]
----
@Configuration
public class MyConfiguration {
@LoadBalanced
@Bean
RestTemplate loadBalanced() {
return new RestTemplate();
}
@Primary
@Bean
RestTemplate restTemplate() {
return new RestTemplate();
}
}
public class MyClass {
@Autowired
private RestTemplate restTemplate;
@Autowired
@LoadBalanced
private RestTemplate loadBalanced;
public String doOtherStuff() {
return loadBalanced.getForObject("http://stores/stores", String.class);
}
public String doStuff() {
return restTemplate.getForObject("http://example.com", String.class);
}
}
----
IMPORTANT: Notice the use of the `@Primary` annotation on the plain `RestTemplate` declaration in the preceding example to disambiguate the unqualified `@Autowired` injection.
TIP: If you see errors such as `java.lang.IllegalArgumentException: Can not set org.springframework.web.client.RestTemplate field com.my.app.Foo.restTemplate to com.sun.proxy.$Proxy89`, try injecting `RestOperations` or setting `spring.aop.proxyTargetClass=true`.
[[multiple-webclient-objects]]
== Multiple WebClient Objects
If you want a `WebClient` that is not load-balanced, create a `WebClient` bean and inject it.
To access the load-balanced `WebClient`, use the `@LoadBalanced` qualifier when you create your `@Bean`, as the following example shows:
[source,java,indent=0]
----
@Configuration
public class MyConfiguration {
@LoadBalanced
@Bean
WebClient.Builder loadBalanced() {
return WebClient.builder();
}
@Primary
@Bean
WebClient.Builder webClient() {
return WebClient.builder();
}
}
public class MyClass {
@Autowired
private WebClient.Builder webClientBuilder;
@Autowired
@LoadBalanced
private WebClient.Builder loadBalanced;
public Mono<String> doOtherStuff() {
return loadBalanced.build().get().uri("http://stores/stores")
.retrieve().bodyToMono(String.class);
}
public Mono<String> doStuff() {
return webClientBuilder.build().get().uri("http://example.com")
.retrieve().bodyToMono(String.class);
}
}
----
[[loadbalanced-webclient]]
== Spring WebFlux `WebClient` as a Load Balancer Client
The Spring WebFlux can work with both reactive and non-reactive `WebClient` configurations, as the topics describe:
* xref:spring-cloud-commons/common-abstractions.adoc#webflux-with-reactive-loadbalancer[Spring WebFlux `WebClient` with `ReactorLoadBalancerExchangeFilterFunction`]
* xref:spring-cloud-commons/common-abstractions.adoc#load-balancer-exchange-filter-function[Spring WebFlux `WebClient` with a Non-reactive Load Balancer Client]
[[webflux-with-reactive-loadbalancer]]
=== Spring WebFlux `WebClient` with `ReactorLoadBalancerExchangeFilterFunction`
You can configure `WebClient` to use the `ReactiveLoadBalancer`.
If you add xref:spring-cloud-commons/loadbalancer.adoc#spring-cloud-loadbalancer-starter[Spring Cloud LoadBalancer starter] to your project
and if `spring-webflux` is on the classpath, `ReactorLoadBalancerExchangeFilterFunction` is auto-configured.
The following example shows how to configure a `WebClient` to use reactive load-balancer:
[source,java,indent=0]
----
public class MyClass {
@Autowired
private ReactorLoadBalancerExchangeFilterFunction lbFunction;
public Mono<String> doOtherStuff() {
return WebClient.builder().baseUrl("http://stores")
.filter(lbFunction)
.build()
.get()
.uri("/stores")
.retrieve()
.bodyToMono(String.class);
}
}
----
The URI needs to use a virtual host name (that is, a service name, not a host name).
The `ReactorLoadBalancer` is used to create a full physical address.
[[load-balancer-exchange-filter-function]]
=== Spring WebFlux `WebClient` with a Non-reactive Load Balancer Client
If `spring-webflux` is on the classpath, `LoadBalancerExchangeFilterFunction`
is auto-configured. Note, however, that this
uses a non-reactive client under the hood.
The following example shows how to configure a `WebClient` to use load-balancer:
[source,java,indent=0]
----
public class MyClass {
@Autowired
private LoadBalancerExchangeFilterFunction lbFunction;
public Mono<String> doOtherStuff() {
return WebClient.builder().baseUrl("http://stores")
.filter(lbFunction)
.build()
.get()
.uri("/stores")
.retrieve()
.bodyToMono(String.class);
}
}
----
The URI needs to use a virtual host name (that is, a service name, not a host name).
The `LoadBalancerClient` is used to create a full physical address.
WARN: This approach is now deprecated.
We suggest that you use xref:spring-cloud-commons/common-abstractions.adoc#webflux-with-reactive-loadbalancer[WebFlux with reactive Load-Balancer]
instead.
[[ignore-network-interfaces]]
== Ignore Network Interfaces
Sometimes, it is useful to ignore certain named network interfaces so that they can be excluded from Service Discovery registration (for example, when running in a Docker container).
A list of regular expressions can be set to cause the desired network interfaces to be ignored.
The following configuration ignores the `docker0` interface and all interfaces that start with `veth`:
.application.yml
----
spring:
cloud:
inetutils:
ignoredInterfaces:
- docker0
- veth.*
----
You can also force the use of only specified network addresses by using a list of regular expressions, as the following example shows:
.bootstrap.yml
----
spring:
cloud:
inetutils:
preferredNetworks:
- 192.168
- 10.0
----
You can also force the use of only site-local addresses, as the following example shows:
.application.yml
----
spring:
cloud:
inetutils:
useOnlySiteLocalInterfaces: true
----
See https://docs.oracle.com/javase/8/docs/api/java/net/Inet4Address.html#isSiteLocalAddress--[Inet4Address.html.isSiteLocalAddress()] for more details about what constitutes a site-local address.
[[http-clients]]
== HTTP Client Factories
Spring Cloud Commons provides beans for creating both Apache HTTP clients (`ApacheHttpClientFactory`) and OK HTTP clients (`OkHttpClientFactory`).
The `OkHttpClientFactory` bean is created only if the OK HTTP jar is on the classpath.
In addition, Spring Cloud Commons provides beans for creating the connection managers used by both clients: `ApacheHttpClientConnectionManagerFactory` for the Apache HTTP client and `OkHttpClientConnectionPoolFactory` for the OK HTTP client.
If you would like to customize how the HTTP clients are created in downstream projects, you can provide your own implementation of these beans.
In addition, if you provide a bean of type `HttpClientBuilder` or `OkHttpClient.Builder`, the default factories use these builders as the basis for the builders returned to downstream projects.
You can also disable the creation of these beans by setting `spring.cloud.httpclientfactories.apache.enabled` or `spring.cloud.httpclientfactories.ok.enabled` to `false`.
[[enabled-features]]
== Enabled Features
Spring Cloud Commons provides a `/features` actuator endpoint.
This endpoint returns features available on the classpath and whether they are enabled.
The information returned includes the feature type, name, version, and vendor.
[[feature-types]]
=== Feature types
There are two types of 'features': abstract and named.
Abstract features are features where an interface or abstract class is defined and that an implementation the creates, such as `DiscoveryClient`, `LoadBalancerClient`, or `LockService`.
The abstract class or interface is used to find a bean of that type in the context.
The version displayed is `bean.getClass().getPackage().getImplementationVersion()`.
Named features are features that do not have a particular class they implement. These features include "`Circuit Breaker`", "`API Gateway`", "`Spring Cloud Bus`", and others. These features require a name and a bean type.
[[declaring-features]]
=== Declaring features
Any module can declare any number of `HasFeature` beans, as the following examples show:
[source,java,indent=0]
----
@Bean
public HasFeatures commonsFeatures() {
return HasFeatures.abstractFeatures(DiscoveryClient.class, LoadBalancerClient.class);
}
@Bean
public HasFeatures consulFeatures() {
return HasFeatures.namedFeatures(
new NamedFeature("Spring Cloud Bus", ConsulBusAutoConfiguration.class),
new NamedFeature("Circuit Breaker", HystrixCommandAspect.class));
}
@Bean
HasFeatures localFeatures() {
return HasFeatures.builder()
.abstractFeature(Something.class)
.namedFeature(new NamedFeature("Some Other Feature", Someother.class))
.abstractFeature(Somethingelse.class)
.build();
}
----
Each of these beans should go in an appropriately guarded `@Configuration`.
[[spring-cloud-compatibility-verification]]
== Spring Cloud Compatibility Verification
Due to the fact that some users have problem with setting up Spring Cloud application, we've decided
to add a compatibility verification mechanism. It will break if your current setup is not compatible
with Spring Cloud requirements, together with a report, showing what exactly went wrong.
At the moment we verify which version of Spring Boot is added to your classpath.
Example of a report
----
***************************
APPLICATION FAILED TO START
***************************
Description:
Your project setup is incompatible with our requirements due to following reasons:
- Spring Boot [2.1.0.RELEASE] is not compatible with this Spring Cloud release train
Action:
Consider applying the following actions:
- Change Spring Boot version to one of the following versions [1.2.x, 1.3.x] .
You can find the latest Spring Boot versions here [https://spring.io/projects/spring-boot#learn].
If you want to learn more about the Spring Cloud Release train compatibility, you can visit this page [https://spring.io/projects/spring-cloud#overview] and check the [Release Trains] section.
----
In order to disable this feature, set `spring.cloud.compatibility-verifier.enabled` to `false`.
If you want to override the compatible Spring Boot versions, just set the
`spring.cloud.compatibility-verifier.compatible-boot-versions` property with a comma separated list
of compatible Spring Boot versions.

515
docs/modules/ROOT/pages/spring-cloud-commons/loadbalancer.adoc

@ -0,0 +1,515 @@ @@ -0,0 +1,515 @@
[[spring-cloud-loadbalancer]]
= Spring Cloud LoadBalancer
Spring Cloud provides its own client-side load-balancer abstraction and implementation. For the load-balancing
mechanism, `ReactiveLoadBalancer` interface has been added and a *Round-Robin-based* and *Random* implementations
have been provided for it. In order to get instances to select from reactive `ServiceInstanceListSupplier`
is used. Currently we support a service-discovery-based implementation of `ServiceInstanceListSupplier`
that retrieves available instances from Service Discovery using a xref:spring-cloud-commons/common-abstractions.adoc#discovery-client[Discovery Client] available in the classpath.
TIP: It is possible to disable Spring Cloud LoadBalancer by setting the value of `spring.cloud.loadbalancer.enabled` to `false`.
[[eager-loading-of-loadbalancer-contexts]]
== Eager loading of LoadBalancer contexts
Spring Cloud LoadBalancer creates a separate Spring child context for each service id. By default, these contexts are initialised lazily, whenever the first request for a service id is being load-balanced.
You can choose to load those contexts eagerly. In order to do that, specify the service ids for which you want to do eager load using the `spring.cloud-loadbalancer.eager-load.clients` property.
[[switching-between-the-load-balancing-algorithms]]
== Switching between the load-balancing algorithms
The `ReactiveLoadBalancer` implementation that is used by default is `RoundRobinLoadBalancer`. To switch to a different implementation, either for selected services or all of them, you can use the xref:spring-cloud-commons/loadbalancer.adoc#custom-loadbalancer-configuration[custom LoadBalancer configurations mechanism].
For example, the following configuration can be passed via `@LoadBalancerClient` annotation to switch to using the `RandomLoadBalancer`:
[[random-loadbalancer-configuration]]
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
ReactorLoadBalancer<ServiceInstance> randomLoadBalancer(Environment environment,
LoadBalancerClientFactory loadBalancerClientFactory) {
String name = environment.getProperty(LoadBalancerClientFactory.PROPERTY_NAME);
return new RandomLoadBalancer(loadBalancerClientFactory
.getLazyProvider(name, ServiceInstanceListSupplier.class),
name);
}
}
----
NOTE: The classes you pass as `@LoadBalancerClient` or `@LoadBalancerClients` configuration arguments should either not be annotated with `@Configuration` or be outside component scan scope.
[[spring-cloud-loadbalancer-integrations]]
== Spring Cloud LoadBalancer integrations
In order to make it easy to use Spring Cloud LoadBalancer, we provide `ReactorLoadBalancerExchangeFilterFunction` that can be used with `WebClient` and `BlockingLoadBalancerClient` that works with `RestTemplate`.
You can see more information and examples of usage in the following sections:
* xref:spring-cloud-commons/common-abstractions.adoc#rest-template-loadbalancer-client[Spring RestTemplate as a Load Balancer Client]
* xref:spring-cloud-commons/common-abstractions.adoc#webclinet-loadbalancer-client[Spring WebClient as a Load Balancer Client]
* xref:spring-cloud-commons/common-abstractions.adoc#webflux-with-reactive-loadbalancer[Spring WebFlux WebClient with `ReactorLoadBalancerExchangeFilterFunction`]
[[loadbalancer-caching]]
== Spring Cloud LoadBalancer Caching
Apart from the basic `ServiceInstanceListSupplier` implementation that retrieves instances via `DiscoveryClient` each time it has to choose an instance, we provide two caching implementations.
[[https://github-com/ben-manes/caffeine[caffeine]-backed-loadbalancer-cache-implementation]]
=== https://github.com/ben-manes/caffeine[Caffeine]-backed LoadBalancer Cache Implementation
If you have `com.github.ben-manes.caffeine:caffeine` in the classpath, Caffeine-based implementation will be used.
See the xref:spring-cloud-commons/loadbalancer.adoc#loadbalancer-cache-configuration[LoadBalancerCacheConfiguration] section for information on how to configure it.
If you are using Caffeine, you can also override the default Caffeine Cache setup for the LoadBalancer by passing your own https://static.javadoc.io/com.github.ben-manes.caffeine/caffeine/2.2.2/com/github/benmanes/caffeine/cache/CaffeineSpec.html[Caffeine Specification]
in the `spring.cloud.loadbalancer.cache.caffeine.spec` property.
WARN: Passing your own Caffeine specification will override any other LoadBalancerCache settings, including xref:spring-cloud-commons/loadbalancer.adoc#loadbalancer-cache-configuration[General LoadBalancer Cache Configuration] fields, such as `ttl` and `capacity`.
[[default-loadbalancer-cache-implementation]]
=== Default LoadBalancer Cache Implementation
If you do not have Caffeine in the classpath, the `DefaultLoadBalancerCache`, which comes automatically with `spring-cloud-starter-loadbalancer`, will be used.
See the xref:spring-cloud-commons/loadbalancer.adoc#loadbalancer-cache-configuration[LoadBalancerCacheConfiguration] section for information on how to configure it.
TIP: To use Caffeine instead of the default cache, add the `com.github.ben-manes.caffeine:caffeine` dependency to classpath.
[[loadbalancer-cache-configuration]]
=== LoadBalancer Cache Configuration
You can set your own `ttl` value (the time after write after which entries should be expired), expressed as `Duration`, by passing a `String` compliant with the https://docs.spring.io/spring-boot/docs/current/reference/html/spring-boot-features.html#boot-features-external-config-conversion-duration[Spring Boot `String` to `Duration` converter syntax].
as the value of the `spring.cloud.loadbalancer.cache.ttl` property.
You can also set your own LoadBalancer cache initial capacity by setting the value of the `spring.cloud.loadbalancer.cache.capacity` property.
The default setup includes `ttl` set to 35 seconds and the default `initialCapacity` is `256`.
You can also altogether disable loadBalancer caching by setting the value of `spring.cloud.loadbalancer.cache.enabled`
to `false`.
WARNING: Although the basic, non-cached, implementation is useful for prototyping and testing, it's much less efficient than the cached versions, so we recommend always using the cached version in production. If the caching is already done by the `DiscoveryClient` implementation, for example `EurekaDiscoveryClient`, the load-balancer caching should be disabled to prevent double caching.
NOTE: When you create your own configuration, if you use `CachingServiceInstanceListSupplier` make sure to place it in the hierarchy directly after the supplier that retrieves the instances over the network, for example, `DiscoveryClientServiceInstanceListSupplier`, before any other filtering suppliers.
[[weighted-load-balancing]]
== Weighted Load-Balancing
To enable weighted load-balancing, we provide the `WeightedServiceInstanceListSupplier`. We use `WeightFunction` to calculate the weight of each instance.
By default, we try to read and parse the weight from the metadata map (the key is `weight`).
If the weight is not specified in the metadata map, we default the weight of this instance to be 1.
You can configure it either by setting the value of `spring.cloud.loadbalancer.configurations` to `weighted` or by providing your own `ServiceInstanceListSupplier` bean, for example:
[[weighted-custom-loadbalancer-configuration]]
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
ConfigurableApplicationContext context) {
return ServiceInstanceListSupplier.builder()
.withDiscoveryClient()
.withWeighted()
.withCaching()
.build(context);
}
}
----
NOTE: You can also customize the weight calculation logic by providing `WeightFunction`.
You can use this sample configuration to make all instances have a random weight:
[[random-weight-weighted-custom-loadbalancer-configuration]]
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
ConfigurableApplicationContext context) {
return ServiceInstanceListSupplier.builder()
.withDiscoveryClient()
.withWeighted(instance -> ThreadLocalRandom.current().nextInt(1, 101))
.withCaching()
.build(context);
}
}
----
[[zone-based-load-balancing]]
== Zone-Based Load-Balancing
To enable zone-based load-balancing, we provide the `ZonePreferenceServiceInstanceListSupplier`.
We use `DiscoveryClient`-specific `zone` configuration (for example, `eureka.instance.metadata-map.zone`) to pick the zone that the client tries to filter available service instances for.
NOTE: You can also override `DiscoveryClient`-specific zone setup by setting the value of `spring.cloud.loadbalancer.zone` property.
WARNING: For the time being, only Eureka Discovery Client is instrumented to set the LoadBalancer zone. For other discovery client, set the `spring.cloud.loadbalancer.zone` property. More instrumentations coming shortly.
NOTE: To determine the zone of a retrieved `ServiceInstance`, we check the value under the `"zone"` key in its metadata map.
The `ZonePreferenceServiceInstanceListSupplier` filters retrieved instances and only returns the ones within the same zone.
If the zone is `null` or there are no instances within the same zone, it returns all the retrieved instances.
In order to use the zone-based load-balancing approach, you will have to instantiate a `ZonePreferenceServiceInstanceListSupplier` bean in a xref:spring-cloud-commons/loadbalancer.adoc#custom-loadbalancer-configuration[custom configuration].
We use delegates to work with `ServiceInstanceListSupplier` beans.
We suggest using a `DiscoveryClientServiceInstanceListSupplier` delegate, wrapping it with a `CachingServiceInstanceListSupplier` to leverage xref:spring-cloud-commons/loadbalancer.adoc#loadbalancer-caching[LoadBalancer caching mechanism], and then passing the resulting bean in the constructor of `ZonePreferenceServiceInstanceListSupplier`.
You can use this sample configuration to set it up:
[[zoned-based-custom-loadbalancer-configuration]]
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
ConfigurableApplicationContext context) {
return ServiceInstanceListSupplier.builder()
.withDiscoveryClient()
.withCaching()
.withZonePreference()
.build(context);
}
}
----
[[instance-health-check-for-loadbalancer]]
== Instance Health-Check for LoadBalancer
It is possible to enable a scheduled HealthCheck for the LoadBalancer. The `HealthCheckServiceInstanceListSupplier`
is provided for that. It regularly verifies if the instances provided by a delegate
`ServiceInstanceListSupplier` are still alive and only returns the healthy instances,
unless there are none - then it returns all the retrieved instances.
TIP: This mechanism is particularly helpful while using the `SimpleDiscoveryClient`. For the
clients backed by an actual Service Registry, it's not necessary to use, as we already get
healthy instances after querying the external ServiceDiscovery.
TIP: This supplier is also recommended for setups with a small number of instances per service
in order to avoid retrying calls on a failing instance.
WARNING: If using any of the Service Discovery-backed suppliers, adding this health-check mechanism is usually not necessary, as we retrieve the health state of the instances directly
from the Service Registry.
TIP: The `HealthCheckServiceInstanceListSupplier` relies on having updated instances provided by a delegate flux. In the rare cases when you want to use a delegate that does not refresh the instances, even though the list of instances may change (such as the `DiscoveryClientServiceInstanceListSupplier` provided by us), you can set `spring.cloud.loadbalancer.health-check.refetch-instances` to `true` to have the instance list refreshed by the `HealthCheckServiceInstanceListSupplier`. You can then also adjust the refretch intervals by modifying the value of `spring.cloud.loadbalancer.health-check.refetch-instances-interval` and opt to disable the additional healthcheck repetitions by setting `spring.cloud.loadbalancer.health-check.repeat-health-check` to `false` as every instances refetch
will also trigger a healthcheck.
`HealthCheckServiceInstanceListSupplier` uses properties prefixed with
`spring.cloud.loadbalancer.health-check`. You can set the `initialDelay` and `interval`
for the scheduler. You can set the default path for the healthcheck URL by setting
the value of the `spring.cloud.loadbalancer.health-check.path.default` property. You can also set a specific value for any given service by setting the value of the `spring.cloud.loadbalancer.health-check.path.[SERVICE_ID]` property, substituting `[SERVICE_ID]` with the correct ID of your service. If the `[SERVICE_ID]` is not specified, `/actuator/health` is used by default. If the `[SERVICE_ID]` is set to `null` or empty as a value, then the health check will not be executed. You can also set a custom port for health-check requests by setting the value of `spring.cloud.loadbalancer.health-check.port`. If none is set, the port under which the requested service is available at the service instance.
TIP: If you rely on the default path (`/actuator/health`), make sure you add `spring-boot-starter-actuator` to your collaborator's dependencies, unless you are planning to add such an endpoint on your own.
TIP: By default, the `healthCheckFlux` will emit on each alive `ServiceInstance` that has been retrieved. You can modify this behaviour by setting the value of `spring.cloud.loadbalancer.health-check.update-results-list` to `false`. If this property is set to `false`, the entire alive instances sequence is first collected into a list and only then emitted, which ensures the flux does not emit values in between the health-check intervals set in properties.
In order to use the health-check scheduler approach, you will have to instantiate a `HealthCheckServiceInstanceListSupplier` bean in a xref:spring-cloud-commons/loadbalancer.adoc#custom-loadbalancer-configuration[custom configuration].
We use delegates to work with `ServiceInstanceListSupplier` beans.
We suggest passing a `DiscoveryClientServiceInstanceListSupplier` delegate in the constructor of `HealthCheckServiceInstanceListSupplier`.
You can use this sample configuration to set it up:
[[health-check-based-custom-loadbalancer-configuration]]
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
ConfigurableApplicationContext context) {
return ServiceInstanceListSupplier.builder()
.withDiscoveryClient()
.withHealthChecks()
.build(context);
}
}
----
TIP: For the non-reactive stack, create this supplier with the `withBlockingHealthChecks()`.
You can also pass your own `WebClient` or `RestTemplate` instance to be used for the checks.
WARNING: `HealthCheckServiceInstanceListSupplier` has its own caching mechanism based on Reactor Flux `replay()`. Therefore, if it's being used, you may want to skip wrapping that supplier with `CachingServiceInstanceListSupplier`.
NOTE: When you create your own configuration, `HealthCheckServiceInstanceListSupplier`, make sure to place it in the hierarchy directly after the supplier that retrieves the instances over the network, for example, `DiscoveryClientServiceInstanceListSupplier`, before any other filtering suppliers.
[[same-instance-preference-for-loadbalancer]]
== Same instance preference for LoadBalancer
You can set up the LoadBalancer in such a way that it prefers the instance that was previously selected, if that instance is available.
For that, you need to use `SameInstancePreferenceServiceInstanceListSupplier`. You can configure it either by setting the value of `spring.cloud.loadbalancer.configurations` to `same-instance-preference` or by providing your own `ServiceInstanceListSupplier` bean -- for example:
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
ConfigurableApplicationContext context) {
return ServiceInstanceListSupplier.builder()
.withDiscoveryClient()
.withSameInstancePreference()
.build(context);
}
}
----
TIP: This is also a replacement for Zookeeper `StickyRule`.
[[request-based-sticky-session-for-loadbalancer]]
== Request-based Sticky Session for LoadBalancer
You can set up the LoadBalancer in such a way that it prefers the instance with `instanceId` provided in a request cookie. We currently support this if the request is being passed to the LoadBalancer through either `ClientRequestContext` or `ServerHttpRequestContext`, which are used by the SC LoadBalancer exchange filter functions and filters.
For that, you need to use the `RequestBasedStickySessionServiceInstanceListSupplier`. You can configure it either by setting the value of `spring.cloud.loadbalancer.configurations` to `request-based-sticky-session` or by providing your own `ServiceInstanceListSupplier` bean -- for example:
[[health-check-based-custom-loadbalancer-configuration-example]]
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
ConfigurableApplicationContext context) {
return ServiceInstanceListSupplier.builder()
.withDiscoveryClient()
.withRequestBasedStickySession()
.build(context);
}
}
----
For that functionality, it is useful to have the selected service instance (which can be different from the one in the original request cookie if that one is not available) to be updated before sending the request forward. To do that, set the value of `spring.cloud.loadbalancer.sticky-session.add-service-instance-cookie` to `true`.
By default, the name of the cookie is `sc-lb-instance-id`. You can modify it by changing the value of the `spring.cloud.loadbalancer.instance-id-cookie-name` property.
NOTE: This feature is currently supported for WebClient-backed load-balancing.
[[spring-cloud-loadbalancer-hints]]
== Spring Cloud LoadBalancer Hints
Spring Cloud LoadBalancer lets you set `String` hints that are passed to the LoadBalancer within the `Request` object and that can later be used in `ReactiveLoadBalancer` implementations that can handle them.
You can set a default hint for all services by setting the value of the `spring.cloud.loadbalancer.hint.default` property. You can also set a specific value
for any given service by setting the value of the `spring.cloud.loadbalancer.hint.[SERVICE_ID]` property, substituting `[SERVICE_ID]` with the correct ID of your service. If the hint is not set by the user, `default` is used.
[[hints-based-loadbalancing]]
== Hint-Based Load-Balancing
We also provide a `HintBasedServiceInstanceListSupplier`, which is a `ServiceInstanceListSupplier` implementation for hint-based instance selection.
`HintBasedServiceInstanceListSupplier` checks for a hint request header (the default header-name is `X-SC-LB-Hint`, but you can modify it by changing the value of the `spring.cloud.loadbalancer.hint-header-name` property) and, if it finds a hint request header, uses the hint value passed in the header to filter service instances.
If no hint header has been added, `HintBasedServiceInstanceListSupplier` uses xref:spring-cloud-commons/loadbalancer.adoc#spring-cloud-loadbalancer-hints[hint values from properties] to filter service instances.
If no hint is set, either by the header or by properties, all service instances provided by the delegate are returned.
While filtering, `HintBasedServiceInstanceListSupplier` looks for service instances that have a matching value set under the `hint` key in their `metadataMap`. If no matching instances are found, all instances provided by the delegate are returned.
You can use the following sample configuration to set it up:
[[hints-based-custom-loadbalancer-configuration]]
[source,java,indent=0]
----
public class CustomLoadBalancerConfiguration {
@Bean
public ServiceInstanceListSupplier discoveryClientServiceInstanceListSupplier(
ConfigurableApplicationContext context) {
return ServiceInstanceListSupplier.builder()
.withDiscoveryClient()
.withCaching()
.withHints()
.build(context);
}
}
----
[[transform-the-load-balanced-http-request]]
== Transform the load-balanced HTTP request
You can use the selected `ServiceInstance` to transform the load-balanced HTTP Request.
For `RestTemplate`, you need to implement and define `LoadBalancerRequestTransformer` as follows:
[source,java,indent=0]
----
@Bean
public LoadBalancerRequestTransformer transformer() {
return new LoadBalancerRequestTransformer() {
@Override
public HttpRequest transformRequest(HttpRequest request, ServiceInstance instance) {
return new HttpRequestWrapper(request) {
@Override
public HttpHeaders getHeaders() {
HttpHeaders headers = new HttpHeaders();
headers.putAll(super.getHeaders());
headers.add("X-InstanceId", instance.getInstanceId());
return headers;
}
};
}
};
}
----
For `WebClient`, you need to implement and define `LoadBalancerClientRequestTransformer` as follows:
[source,java,indent=0]
----
@Bean
public LoadBalancerClientRequestTransformer transformer() {
return new LoadBalancerClientRequestTransformer() {
@Override
public ClientRequest transformRequest(ClientRequest request, ServiceInstance instance) {
return ClientRequest.from(request)
.header("X-InstanceId", instance.getInstanceId())
.build();
}
};
}
----
If multiple transformers are defined, they are applied in the order in which Beans are defined.
Alternatively, you can use `LoadBalancerRequestTransformer.DEFAULT_ORDER` or `LoadBalancerClientRequestTransformer.DEFAULT_ORDER` to specify the order.
[[spring-cloud-loadbalancer-starter]]
== Spring Cloud LoadBalancer Starter
We also provide a starter that allows you to easily add Spring Cloud LoadBalancer in a Spring Boot app.
In order to use it, just add `org.springframework.cloud:spring-cloud-starter-loadbalancer` to your Spring Cloud dependencies in your build file.
NOTE: Spring Cloud LoadBalancer starter includes
https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-caching.html[Spring Boot Caching]
and https://github.com/stoyanr/Evictor[Evictor].
[[custom-loadbalancer-configuration]]
== Passing Your Own Spring Cloud LoadBalancer Configuration
You can also use the `@LoadBalancerClient` annotation to pass your own load-balancer client configuration, passing the name of the load-balancer client and the configuration class, as follows:
[source,java,indent=0]
----
@Configuration
@LoadBalancerClient(value = "stores", configuration = CustomLoadBalancerConfiguration.class)
public class MyConfiguration {
@Bean
@LoadBalanced
public WebClient.Builder loadBalancedWebClientBuilder() {
return WebClient.builder();
}
}
----
TIP: In order to make working on your own LoadBalancer configuration easier, we have added a `builder()` method to the `ServiceInstanceListSupplier` class.
TIP: You can also use our alternative predefined configurations in place of the default ones by setting the value of `spring.cloud.loadbalancer.configurations` property to `zone-preference` to use `ZonePreferenceServiceInstanceListSupplier` with caching or to `health-check` to use `HealthCheckServiceInstanceListSupplier` with caching.
You can use this feature to instantiate different implementations of `ServiceInstanceListSupplier` or `ReactorLoadBalancer`, either written by you, or provided by us as alternatives (for example `ZonePreferenceServiceInstanceListSupplier`) to override the default setup.
You can see an example of a custom configuration xref:spring-cloud-commons/loadbalancer.adoc#zoned-based-custom-loadbalancer-configuration[here].
NOTE: The annotation `value` arguments (`stores` in the example above) specifies the service id of the service that we should send the requests to with the given custom configuration.
You can also pass multiple configurations (for more than one load-balancer client) through the `@LoadBalancerClients` annotation, as the following example shows:
[source,java,indent=0]
----
@Configuration
@LoadBalancerClients({@LoadBalancerClient(value = "stores", configuration = StoresLoadBalancerClientConfiguration.class), @LoadBalancerClient(value = "customers", configuration = CustomersLoadBalancerClientConfiguration.class)})
public class MyConfiguration {
@Bean
@LoadBalanced
public WebClient.Builder loadBalancedWebClientBuilder() {
return WebClient.builder();
}
}
----
NOTE: The classes you pass as `@LoadBalancerClient` or `@LoadBalancerClients` configuration arguments should either not be annotated with `@Configuration` or be outside component scan scope.
NOTE: When you create your own configuration, if you use `CachingServiceInstanceListSupplier` or `HealthCheckServiceInstanceListSupplier`, makes sure to use one of them, not both, and make sure to place it in the hierarchy directly after the supplier that retrieves the instances over the network, for example, `DiscoveryClientServiceInstanceListSupplier`, before any other filtering suppliers.
[[loadbalancer-lifecycle]]
== Spring Cloud LoadBalancer Lifecycle
One type of bean that it may be useful to register using xref:spring-cloud-commons/loadbalancer.adoc#custom-loadbalancer-configuration[Custom LoadBalancer configuration] is `LoadBalancerLifecycle`.
The `LoadBalancerLifecycle` beans provide callback methods, named `onStart(Request<RC> request)`, `onStartRequest(Request<RC> request, Response<T> lbResponse)` and `onComplete(CompletionContext<RES, T, RC> completionContext)`, that you should implement to specify what actions should take place before and after load-balancing.
`onStart(Request<RC> request)` takes a `Request` object as a parameter. It contains data that is used to select an appropriate instance, including the downstream client request and xref:spring-cloud-commons/loadbalancer.adoc#spring-cloud-loadbalancer-hints[hint]. `onStartRequest` also takes the `Request` object and, additionally, the `Response<T>` object as parameters. On the other hand, a `CompletionContext` object is provided to the `onComplete(CompletionContext<RES, T, RC> completionContext)` method. It contains the LoadBalancer `Response`, including the selected service instance, the `Status` of the request executed against that service instance and (if available) the response returned to the downstream client, and (if an exception has occurred) the corresponding `Throwable`.
The `supports(Class requestContextClass, Class responseClass,
Class serverTypeClass)` method can be used to determine whether the processor in question handles objects of provided types. If not overridden by the user, it returns `true`.
NOTE: In the preceding method calls, `RC` means `RequestContext` type, `RES` means client response type, and `T` means returned server type.
[[loadbalancer-micrometer-stats-lifecycle]]
== Spring Cloud LoadBalancer Statistics
We provide a `LoadBalancerLifecycle` bean called `MicrometerStatsLoadBalancerLifecycle`, which uses Micrometer to provide statistics for load-balanced calls.
In order to get this bean added to your application context,
set the value of the `spring.cloud.loadbalancer.stats.micrometer.enabled` to `true` and have a `MeterRegistry` available (for example, by adding https://docs.spring.io/spring-boot/docs/current/reference/html/production-ready-features.html[Spring Boot Actuator] to your project).
`MicrometerStatsLoadBalancerLifecycle` registers the following meters in `MeterRegistry`:
* `loadbalancer.requests.active`: A gauge that allows you to monitor the number of currently active requests for any service instance (service instance data available via tags);
* `loadbalancer.requests.success`: A timer that measures the time of execution of any load-balanced requests that have ended in passing a response on to the underlying client;
* `loadbalancer.requests.failed`: A timer that measures the time of execution of any load-balanced requests that have ended with an exception;
* `loadbalancer.requests.discard`: A counter that measures the number of discarded load-balanced requests, i.e. requests where a service instance to run the request on has not been retrieved by the LoadBalancer.
Additional information regarding the service instances, request data, and response data is added to metrics via tags whenever available.
NOTE: For some implementations, such as `BlockingLoadBalancerClient`, request and response data might not be available, as we establish generic types from arguments and might not be able to determine the types and read the data.
NOTE: The meters are registered in the registry when at least one record is added for a given meter.
TIP: You can further configure the behavior of those metrics (for example, add https://micrometer.io/docs/concepts#_histograms_and_percentiles[publishing percentiles and histograms]) by https://docs.spring.io/spring-boot/docs/current/reference/html/production-ready-features.html#production-ready-metrics-per-meter-properties[adding `MeterFilters`].
[[configuring-individual-loadbalancerclients]]
== Configuring Individual LoadBalancerClients
Individual Loadbalancer clients may be configured individually with a different prefix `spring.cloud.loadbalancer.clients.<clientId>.*` where `clientId` is the name of the loadbalancer. Default configuration values may be set in the `spring.cloud.loadbalancer.*` namespace and will be merged with the client specific values taking precedence
.application.yml
----
spring:
cloud:
loadbalancer:
health-check:
initial-delay: 1s
clients:
myclient:
health-check:
interval: 30s
----
The above example will result in a merged health-check `@ConfigurationProperties` object with `initial-delay=1s` and `interval=30s`.
The per-client configuration properties work for most of the properties, apart from the following global ones:
- `spring.cloud.loadbalancer.enabled` - globally enables or disables load-balancing
- `spring.cloud.loadbalancer.retry.enabled` - globally enables or disables load-balanced retries. If you enable it globally, you can still disable retries for specific clients using the `client`-prefixed properties, but not the other way round
- `spring.cloud.loadbalancer.cache.enabled` - globally enables or disables LoadBalancer caching. If you enable it globally, you can still disable caching for specific clients by creating a xref:spring-cloud-commons/loadbalancer.adoc#custom-loadbalancer-configuration[custom configuration] that does not include the `CachingServiceInstanceListSupplier` in the `ServiceInstanceListSupplier` delegates hierarchy, but not the other way round.
- `spring.cloud.loadbalancer.stats.micrometer.enabled` - globally enables or disables LoadBalancer Micrometer metrics
NOTE: For the properties where maps where already used, where you can specify a different value per-client without using the `clients` keyword (for example, `hints`, `health-check.path`), we have kept that behaviour in order to keep the library backwards compatible. It will be modified in the next major release.
NOTE: Starting with `4.1.0`, we have introduced the `callGetWithRequestOnDelegates` flag in `LoadBalancerProperties`. If this flag is set to `true`, `ServiceInstanceListSupplier#get(Request request)` method will be implemented to call `delegate.get(request)` in classes assignable from `DelegatingServiceInstanceListSupplier` that don't already implement that method, with the exclusion of `CachingServiceInstanceListSupplier` and `HealthCheckServiceInstanceListSupplier`, which should be placed in the instance supplier hierarchy directly after the supplier performing instance retrieval over the network, before any request-based filtering is done. It is set to `true` by default.
[[-aot-and-native-image-support]]
== AOT and Native Image Support
Since `4.0.0`, Spring Cloud LoadBalancer supports Spring AOT transformations and native images. However, to use this feature, you need to explicitly define your `LoadBalancerClient` service IDs. You can do so by using the `value` or `name` attributes of the `@LoadBalancerClient` annotation or as values of the `spring.cloud.loadbalancer.eager-load.clients` property.

89
docs/modules/ROOT/pages/spring-cloud-commons/security.adoc

@ -0,0 +1,89 @@ @@ -0,0 +1,89 @@
[[spring-cloud-security]]
= Security
[[spring-cloud-security-single-sign-on]]
== Single Sign On
NOTE: All of the OAuth2 SSO and resource server features moved to Spring Boot
in version 1.3. You can find documentation in the
https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/[Spring Boot user guide].
[[spring-cloud-security-client-token-relay]]
=== Client Token Relay
If your app is a user facing OAuth2 client (i.e. has declared
`@EnableOAuth2Sso` or `@EnableOAuth2Client`) then it has an
`OAuth2ClientContext` in request scope from Spring Boot. You can
create your own `OAuth2RestTemplate` from this context and an
autowired `OAuth2ProtectedResourceDetails`, and then the context will
always forward the access token downstream, also refreshing the access
token automatically if it expires. (These are features of Spring
Security and Spring Boot.)
[[spring-cloud-security-resource-server-token-relay]]
=== Resource Server Token Relay
If your app has `@EnableResourceServer` you might want to relay the
incoming token downstream to other services. If you use a
`RestTemplate` to contact the downstream services then this is just a
matter of how to create the template with the right context.
If your service uses `UserInfoTokenServices` to authenticate incoming
tokens (i.e. it is using the `security.oauth2.user-info-uri`
configuration), then you can simply create an `OAuth2RestTemplate`
using an autowired `OAuth2ClientContext` (it will be populated by the
authentication process before it hits the backend code). Equivalently
(with Spring Boot 1.4), you can inject a
`UserInfoRestTemplateFactory` and grab its `OAuth2RestTemplate` in
your configuration. For example:
.MyConfiguration.java
[source,java]
----
@Bean
public OAuth2RestTemplate restTemplate(UserInfoRestTemplateFactory factory) {
return factory.getUserInfoRestTemplate();
}
----
This rest template will then have the same `OAuth2ClientContext`
(request-scoped) that is used by the authentication filter, so you can
use it to send requests with the same access token.
If your app is not using `UserInfoTokenServices` but is still a client
(i.e. it declares `@EnableOAuth2Client` or `@EnableOAuth2Sso`), then
with Spring Security Cloud any `OAuth2RestOperations` that the user
creates from an `@Autowired` `OAuth2Context` will also forward
tokens. This feature is implemented by default as an MVC handler
interceptor, so it only works in Spring MVC. If you are not using MVC
you can use a custom filter or AOP interceptor wrapping an
`AccessTokenContextRelay` to provide the same feature.
Here's a basic
example showing the use of an autowired rest template created
elsewhere ("foo.com" is a Resource Server accepting the same tokens as
the surrounding app):
.MyController.java
[source,java]
----
@Autowired
private OAuth2RestOperations restTemplate;
@RequestMapping("/relay")
public String relay() {
ResponseEntity<String> response =
restTemplate.getForEntity("https://foo.com/bar", String.class);
return "Success! (" + response.getBody() + ")";
}
----
If you don't want to forward tokens (and that is a valid
choice, since you might want to act as yourself, rather than the
client that sent you the token), then you only need to create your own
`OAuth2Context` instead of autowiring the default one.
Feign clients will also pick up an interceptor that uses the
`OAuth2ClientContext` if it is available, so they should also do a
token relay anywhere where a `RestTemplate` would.

3
docs/modules/ROOT/partials/_attributes.adoc

@ -0,0 +1,3 @@ @@ -0,0 +1,3 @@
:sc-ext: java
:project-full-name: Spring Cloud Commons
:all: {asterisk}{asterisk}

37
docs/pom.xml

@ -17,15 +17,14 @@ @@ -17,15 +17,14 @@
<docs.main>spring-cloud-commons</docs.main>
<main.basedir>${basedir}/..</main.basedir>
<configprops.inclusionPattern>spring.cloud.*</configprops.inclusionPattern>
<upload-docs-zip.phase>deploy</upload-docs-zip.phase>
<!-- Don't upload docs jar to central / repo.spring.io -->
<maven-deploy-plugin-default.phase>none</maven-deploy-plugin-default.phase>
<!-- Observability -->
<micrometer-docs-generator.version>1.0.0</micrometer-docs-generator.version>
<micrometer-docs-generator.version>1.0.2</micrometer-docs-generator.version>
<micrometer-docs-generator.inputPath>${maven.multiModuleProjectDirectory}/spring-cloud-commons/</micrometer-docs-generator.inputPath>
<micrometer-docs-generator.inclusionPattern>.*</micrometer-docs-generator.inclusionPattern>
<micrometer-docs-generator.outputPath>${maven.multiModuleProjectDirectory}/target/</micrometer-docs-generator.outputPath>
<micrometer-docs-generator.outputPath>${maven.multiModuleProjectDirectory}/docs/modules/ROOT/partials/</micrometer-docs-generator.outputPath>
</properties>
<dependencies>
<dependency>
@ -44,18 +43,28 @@ @@ -44,18 +43,28 @@
<profile>
<id>docs</id>
<build>
<resources>
<resource>
<directory>src/main/antora/resources/antora-resources</directory>
<filtering>true</filtering>
</resource>
</resources>
<plugins>
<plugin>
<groupId>pl.project13.maven</groupId>
<artifactId>git-commit-id-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<executions>
<execution>
<id>generate-docs</id>
<phase>prepare-package</phase>
<phase>generate-resources</phase>
<goals>
<goal>java</goal>
</goals>
@ -80,16 +89,20 @@ @@ -80,16 +89,20 @@
</dependencies>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<groupId>io.spring.maven.antora</groupId>
<artifactId>antora-component-version-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-resources-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.asciidoctor</groupId>
<artifactId>asciidoctor-maven-plugin</artifactId>
<groupId>io.spring.maven.antora</groupId>
<artifactId>antora-maven-plugin</artifactId>
<executions>
<execution>
<phase>prepare-package</phase>
<goals>
<goal>antora</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>

20
docs/src/main/antora/resources/antora-resources/antora.yml

@ -0,0 +1,20 @@ @@ -0,0 +1,20 @@
version: @antora-component.version@
prerelease: @antora-component.prerelease@
asciidoc:
attributes:
attribute-missing: 'warn'
chomp: 'all'
project-root: @maven.multiModuleProjectDirectory@
github-repo: @docs.main@
github-raw: https://raw.githubusercontent.com/spring-cloud/@docs.main@/@github-tag@
github-code: https://github.com/spring-cloud/@docs.main@/tree/@github-tag@
github-issues: https://github.com/spring-cloud/@docs.main@/issues/
github-wiki: https://github.com/spring-cloud/@docs.main@/wiki
spring-cloud-version: @project.version@
github-tag: @github-tag@
version-type: @version-type@
docs-url: https://docs.spring.io/@docs.main@/docs/@project.version@
raw-docs-url: https://raw.githubusercontent.com/spring-cloud/@docs.main@/@github-tag@
project-version: @project.version@
project-name: @docs.main@

9
docs/src/main/asciidoc/README.adoc

@ -1,9 +1,12 @@ @@ -1,9 +1,12 @@
include::intro.adoc[]
== Building
[[building]]
= Building
:page-section-summary-toc: 1
include::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/docs/src/main/asciidoc/building.adoc[]
== Contributing
[[contributing]]
= Contributing
:page-section-summary-toc: 1
include::https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/docs/src/main/asciidoc/contributing.adoc[]

16
docs/src/main/asciidoc/_attributes.adoc

@ -1,16 +0,0 @@ @@ -1,16 +0,0 @@
:doctype: book
:idprefix:
:idseparator: -
:toc: left
:toclevels: 4
:tabsize: 4
:numbered:
:sectanchors:
:sectnums:
:icons: font
:hide-uri-scheme:
:docinfo: shared,private
:sc-ext: java
:project-full-name: Spring Cloud Commons
:all: {asterisk}{asterisk}

83
docs/src/main/asciidoc/_configprops.adoc

@ -1,83 +0,0 @@ @@ -1,83 +0,0 @@
|===
|Name | Default | Description
|spring.cloud.compatibility-verifier.compatible-boot-versions | `+++3.2.x+++` | Default accepted versions for the Spring Boot dependency. You can set {@code x} for the patch version if you don't want to specify a concrete value. Example: {@code 3.4.x}
|spring.cloud.compatibility-verifier.enabled | `+++false+++` | Enables creation of Spring Cloud compatibility verification.
|spring.cloud.config.allow-override | `+++true+++` | Flag to indicate that {@link #isOverrideSystemProperties() systemPropertiesOverride} can be used. Set to false to prevent users from changing the default accidentally. Default true.
|spring.cloud.config.initialize-on-context-refresh | `+++false+++` | Flag to initialize bootstrap configuration on context refresh event. Default false.
|spring.cloud.config.override-none | `+++false+++` | Flag to indicate that when {@link #setAllowOverride(boolean) allowOverride} is true, external properties should take lowest priority and should not override any existing property sources (including local config files). Default false.
|spring.cloud.config.override-system-properties | `+++true+++` | Flag to indicate that the external properties should override system properties. Default true.
|spring.cloud.decrypt-environment-post-processor.enabled | `+++true+++` | Enable the DecryptEnvironmentPostProcessor.
|spring.cloud.discovery.client.composite-indicator.enabled | `+++true+++` | Enables discovery client composite health indicator.
|spring.cloud.discovery.client.health-indicator.enabled | `+++true+++` |
|spring.cloud.discovery.client.health-indicator.include-description | `+++false+++` |
|spring.cloud.discovery.client.health-indicator.use-services-query | `+++true+++` | Whether or not the indicator should use {@link DiscoveryClient#getServices} to check its health. When set to {@code false} the indicator instead uses the lighter {@link DiscoveryClient#probe()}. This can be helpful in large deployments where the number of services returned makes the operation unnecessarily heavy.
|spring.cloud.discovery.client.simple.instances | |
|spring.cloud.discovery.client.simple.local.host | |
|spring.cloud.discovery.client.simple.local.instance-id | |
|spring.cloud.discovery.client.simple.local.metadata | |
|spring.cloud.discovery.client.simple.local.port | `+++0+++` |
|spring.cloud.discovery.client.simple.local.secure | `+++false+++` |
|spring.cloud.discovery.client.simple.local.service-id | |
|spring.cloud.discovery.client.simple.local.uri | |
|spring.cloud.discovery.client.simple.order | |
|spring.cloud.discovery.enabled | `+++true+++` | Enables discovery client health indicators.
|spring.cloud.features.enabled | `+++true+++` | Enables the features endpoint.
|spring.cloud.httpclientfactories.apache.enabled | `+++true+++` | Enables creation of Apache Http Client factory beans.
|spring.cloud.httpclientfactories.ok.enabled | `+++true+++` | Enables creation of OK Http Client factory beans.
|spring.cloud.hypermedia.refresh.fixed-delay | `+++5000+++` |
|spring.cloud.hypermedia.refresh.initial-delay | `+++10000+++` |
|spring.cloud.inetutils.default-hostname | `+++localhost+++` | The default hostname. Used in case of errors.
|spring.cloud.inetutils.default-ip-address | `+++127.0.0.1+++` | The default IP address. Used in case of errors.
|spring.cloud.inetutils.ignored-interfaces | | List of Java regular expressions for network interfaces that will be ignored.
|spring.cloud.inetutils.preferred-networks | | List of Java regular expressions for network addresses that will be preferred.
|spring.cloud.inetutils.timeout-seconds | `+++1+++` | Timeout, in seconds, for calculating hostname.
|spring.cloud.inetutils.use-only-site-local-interfaces | `+++false+++` | Whether to use only interfaces with site local addresses. See {@link InetAddress#isSiteLocalAddress()} for more details.
|spring.cloud.loadbalancer.cache.caffeine.spec | | The spec to use to create caches. See CaffeineSpec for more details on the spec format.
|spring.cloud.loadbalancer.cache.capacity | `+++256+++` | Initial cache capacity expressed as int.
|spring.cloud.loadbalancer.cache.enabled | `+++true+++` | Enables Spring Cloud LoadBalancer caching mechanism.
|spring.cloud.loadbalancer.cache.ttl | `+++35s+++` | Time To Live - time counted from writing of the record, after which cache entries are expired, expressed as a {@link Duration}. The property {@link String} has to be in keeping with the appropriate syntax as specified in Spring Boot <code>StringToDurationConverter</code>. @see <a href= "https://github.com/spring-projects/spring-boot/blob/master/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/convert/StringToDurationConverter.java">StringToDurationConverter.java</a>
|spring.cloud.loadbalancer.call-get-with-request-on-delegates | `+++true+++` | If this flag is set to {@code true}, {@code ServiceInstanceListSupplier#get(Request request)} method will be implemented to call {@code delegate.get(request)} in classes assignable from {@code DelegatingServiceInstanceListSupplier} that don't already implement that method, with the exclusion of {@code CachingServiceInstanceListSupplier} and {@code HealthCheckServiceInstanceListSupplier}, which should be placed in the instance supplier hierarchy directly after the supplier performing instance retrieval over the network, before any request-based filtering is done, {@code true} by default.
|spring.cloud.loadbalancer.clients | |
|spring.cloud.loadbalancer.configurations | `+++default+++` | Enables a predefined LoadBalancer configuration.
|spring.cloud.loadbalancer.eager-load.clients | | Names of the clients.
|spring.cloud.loadbalancer.enabled | `+++true+++` | Enables Spring Cloud LoadBalancer.
|spring.cloud.loadbalancer.health-check.initial-delay | `+++0+++` | Initial delay value for the HealthCheck scheduler.
|spring.cloud.loadbalancer.health-check.interval | `+++25s+++` | Interval for rerunning the HealthCheck scheduler.
|spring.cloud.loadbalancer.health-check.interval | `+++25s+++` | Interval for rerunning the HealthCheck scheduler.
|spring.cloud.loadbalancer.health-check.path | | Path at which the health-check request should be made. Can be set up per `serviceId`. A `default` value can be set up as well. If none is set up, `/actuator/health` will be used.
|spring.cloud.loadbalancer.health-check.port | | Path at which the health-check request should be made. If none is set, the port under which the requested service is available at the service instance.
|spring.cloud.loadbalancer.health-check.refetch-instances | `+++false+++` | Indicates whether the instances should be refetched by the `HealthCheckServiceInstanceListSupplier`. This can be used if the instances can be updated and the underlying delegate does not provide an ongoing flux.
|spring.cloud.loadbalancer.health-check.refetch-instances-interval | `+++25s+++` | Interval for refetching available service instances.
|spring.cloud.loadbalancer.health-check.repeat-health-check | `+++true+++` | Indicates whether health checks should keep repeating. It might be useful to set it to `false` if periodically refetching the instances, as every refetch will also trigger a healthcheck.
|spring.cloud.loadbalancer.health-check.update-results-list | `+++true+++` | Indicates whether the {@code healthCheckFlux} should emit on each alive {@link ServiceInstance} that has been retrieved. If set to {@code false}, the entire alive instances sequence is first collected into a list and only then emitted.
|spring.cloud.loadbalancer.hint | | Allows setting the value of <code>hint</code> that is passed on to the LoadBalancer request and can subsequently be used in {@link ReactiveLoadBalancer} implementations.
|spring.cloud.loadbalancer.hint-header-name | `+++X-SC-LB-Hint+++` | Allows setting the name of the header used for passing the hint for hint-based service instance filtering.
|spring.cloud.loadbalancer.retry.avoid-previous-instance | `+++true+++` | Enables wrapping ServiceInstanceListSupplier beans with `RetryAwareServiceInstanceListSupplier` if Spring-Retry is in the classpath.
|spring.cloud.loadbalancer.retry.backoff.enabled | `+++false+++` | Indicates whether Reactor Retry backoffs should be applied.
|spring.cloud.loadbalancer.retry.backoff.jitter | `+++0.5+++` | Used to set `RetryBackoffSpec.jitter`.
|spring.cloud.loadbalancer.retry.backoff.max-backoff | `+++Long.MAX ms+++` | Used to set `RetryBackoffSpec.maxBackoff`.
|spring.cloud.loadbalancer.retry.backoff.min-backoff | `+++5 ms+++` | Used to set `RetryBackoffSpec#minBackoff`.
|spring.cloud.loadbalancer.retry.enabled | `+++true+++` | Enables LoadBalancer retries.
|spring.cloud.loadbalancer.retry.max-retries-on-next-service-instance | `+++1+++` | Number of retries to be executed on the next `ServiceInstance`. A `ServiceInstance` is chosen before each retry call.
|spring.cloud.loadbalancer.retry.max-retries-on-same-service-instance | `+++0+++` | Number of retries to be executed on the same `ServiceInstance`.
|spring.cloud.loadbalancer.retry.retry-on-all-exceptions | `+++false+++` | Indicates retries should be attempted for all exceptions, not only those specified in `retryableExceptions`.
|spring.cloud.loadbalancer.retry.retry-on-all-operations | `+++false+++` | Indicates retries should be attempted on operations other than `HttpMethod.GET`.
|spring.cloud.loadbalancer.retry.retryable-exceptions | `+++{}+++` | A `Set` of `Throwable` classes that should trigger a retry.
|spring.cloud.loadbalancer.retry.retryable-status-codes | `+++{}+++` | A `Set` of status codes that should trigger a retry.
|spring.cloud.loadbalancer.service-discovery.timeout | | String representation of Duration of the timeout for calls to service discovery.
|spring.cloud.loadbalancer.stats.micrometer.enabled | `+++false+++` | Enables Spring Cloud LoadBalancer Micrometer stats.
|spring.cloud.loadbalancer.sticky-session.add-service-instance-cookie | `+++false+++` | Indicates whether a cookie with the newly selected instance should be added by LoadBalancer.
|spring.cloud.loadbalancer.sticky-session.instance-id-cookie-name | `+++sc-lb-instance-id+++` | The name of the cookie holding the preferred instance id.
|spring.cloud.loadbalancer.x-forwarded.enabled | `+++false+++` | To Enable X-Forwarded Headers.
|spring.cloud.loadbalancer.zone | | Spring Cloud LoadBalancer zone.
|spring.cloud.refresh.additional-property-sources-to-retain | | Additional property sources to retain during a refresh. Typically only system property sources are retained. This property allows property sources, such as property sources created by EnvironmentPostProcessors to be retained as well.
|spring.cloud.refresh.enabled | `+++true+++` | Enables autoconfiguration for the refresh scope and associated features.
|spring.cloud.refresh.extra-refreshable | `+++true+++` | Additional class names for beans to post process into refresh scope.
|spring.cloud.refresh.never-refreshable | `+++true+++` | Comma separated list of class names for beans to never be refreshed or rebound.
|spring.cloud.service-registry.auto-registration.enabled | `+++true+++` | Whether service auto-registration is enabled. Defaults to true.
|spring.cloud.service-registry.auto-registration.fail-fast | `+++false+++` | Whether startup fails if there is no AutoServiceRegistration. Defaults to false.
|spring.cloud.service-registry.auto-registration.register-management | `+++true+++` | Whether to register the management as a service. Defaults to true.
|spring.cloud.util.enabled | `+++true+++` | Enables creation of Spring Cloud utility beans.
|===

8
docs/src/main/asciidoc/_observability.adoc

@ -1,8 +0,0 @@ @@ -1,8 +0,0 @@
:root-target: ../../../target/
[[observability]]
== Observability metadata
include::{root-target}_metrics.adoc[]
include::{root-target}_spans.adoc[]

330
docs/src/main/asciidoc/ghpages.sh

@ -1,330 +0,0 @@ @@ -1,330 +0,0 @@
#!/bin/bash -x
set -e
# Set default props like MAVEN_PATH, ROOT_FOLDER etc.
function set_default_props() {
# The script should be run from the root folder
ROOT_FOLDER=`pwd`
echo "Current folder is ${ROOT_FOLDER}"
if [[ ! -e "${ROOT_FOLDER}/.git" ]]; then
echo "You're not in the root folder of the project!"
exit 1
fi
# Prop that will let commit the changes
COMMIT_CHANGES="no"
MAVEN_PATH=${MAVEN_PATH:-}
echo "Path to Maven is [${MAVEN_PATH}]"
REPO_NAME=${PWD##*/}
echo "Repo name is [${REPO_NAME}]"
SPRING_CLOUD_STATIC_REPO=${SPRING_CLOUD_STATIC_REPO:-git@github.com:spring-cloud/spring-cloud-static.git}
echo "Spring Cloud Static repo is [${SPRING_CLOUD_STATIC_REPO}"
}
# Check if gh-pages exists and docs have been built
function check_if_anything_to_sync() {
git remote set-url --push origin `git config remote.origin.url | sed -e 's/^git:/https:/'`
if ! (git remote set-branches --add origin gh-pages && git fetch -q); then
echo "No gh-pages, so not syncing"
exit 0
fi
if ! [ -d docs/target/generated-docs ] && ! [ "${BUILD}" == "yes" ]; then
echo "No gh-pages sources in docs/target/generated-docs, so not syncing"
exit 0
fi
}
function retrieve_current_branch() {
# Code getting the name of the current branch. For master we want to publish as we did until now
# https://stackoverflow.com/questions/1593051/how-to-programmatically-determine-the-current-checked-out-git-branch
# If there is a branch already passed will reuse it - otherwise will try to find it
CURRENT_BRANCH=${BRANCH}
if [[ -z "${CURRENT_BRANCH}" ]] ; then
CURRENT_BRANCH=$(git symbolic-ref -q HEAD)
CURRENT_BRANCH=${CURRENT_BRANCH##refs/heads/}
CURRENT_BRANCH=${CURRENT_BRANCH:-HEAD}
fi
echo "Current branch is [${CURRENT_BRANCH}]"
git checkout ${CURRENT_BRANCH} || echo "Failed to check the branch... continuing with the script"
}
# Switches to the provided value of the release version. We always prefix it with `v`
function switch_to_tag() {
git checkout v${VERSION}
}
# Build the docs if switch is on
function build_docs_if_applicable() {
if [[ "${BUILD}" == "yes" ]] ; then
./mvnw clean install -P docs -pl docs -DskipTests
fi
}
# Get the name of the `docs.main` property
# Get allowed branches - assumes that a `docs` module is available under `docs` profile
function retrieve_doc_properties() {
MAIN_ADOC_VALUE=$("${MAVEN_PATH}"mvn -q \
-Dexec.executable="echo" \
-Dexec.args='${docs.main}' \
--non-recursive \
org.codehaus.mojo:exec-maven-plugin:1.3.1:exec)
echo "Extracted 'main.adoc' from Maven build [${MAIN_ADOC_VALUE}]"
ALLOW_PROPERTY=${ALLOW_PROPERTY:-"docs.allowed.branches"}
ALLOWED_BRANCHES_VALUE=$("${MAVEN_PATH}"mvn -q \
-Dexec.executable="echo" \
-Dexec.args="\${${ALLOW_PROPERTY}}" \
org.codehaus.mojo:exec-maven-plugin:1.3.1:exec \
-P docs \
-pl docs)
echo "Extracted '${ALLOW_PROPERTY}' from Maven build [${ALLOWED_BRANCHES_VALUE}]"
}
# Stash any outstanding changes
function stash_changes() {
git diff-index --quiet HEAD && dirty=$? || (echo "Failed to check if the current repo is dirty. Assuming that it is." && dirty="1")
if [ "$dirty" != "0" ]; then git stash; fi
}
# Switch to gh-pages branch to sync it with current branch
function add_docs_from_target() {
local DESTINATION_REPO_FOLDER
if [[ -z "${DESTINATION}" && -z "${CLONE}" ]] ; then
DESTINATION_REPO_FOLDER=${ROOT_FOLDER}
elif [[ "${CLONE}" == "yes" ]]; then
mkdir -p ${ROOT_FOLDER}/target
local clonedStatic=${ROOT_FOLDER}/target/spring-cloud-static
if [[ ! -e "${clonedStatic}/.git" ]]; then
echo "Cloning Spring Cloud Static to target"
git clone ${SPRING_CLOUD_STATIC_REPO} ${clonedStatic} && git checkout gh-pages
else
echo "Spring Cloud Static already cloned - will pull changes"
cd ${clonedStatic} && git checkout gh-pages && git pull origin gh-pages
fi
DESTINATION_REPO_FOLDER=${clonedStatic}/${REPO_NAME}
mkdir -p ${DESTINATION_REPO_FOLDER}
else
if [[ ! -e "${DESTINATION}/.git" ]]; then
echo "[${DESTINATION}] is not a git repository"
exit 1
fi
DESTINATION_REPO_FOLDER=${DESTINATION}/${REPO_NAME}
mkdir -p ${DESTINATION_REPO_FOLDER}
echo "Destination was provided [${DESTINATION}]"
fi
cd ${DESTINATION_REPO_FOLDER}
git checkout gh-pages
git pull origin gh-pages
# Add git branches
###################################################################
if [[ -z "${VERSION}" ]] ; then
copy_docs_for_current_version
else
copy_docs_for_provided_version
fi
commit_changes_if_applicable
}
# Copies the docs by using the retrieved properties from Maven build
function copy_docs_for_current_version() {
if [[ "${CURRENT_BRANCH}" == "main" ]] ; then
echo -e "Current branch is main - will copy the current docs only to the root folder"
for f in docs/target/generated-docs/*; do
file=${f#docs/target/generated-docs/*}
if ! git ls-files -i -o --exclude-standard --directory | grep -q ^$file$; then
# Not ignored...
cp -rf $f ${ROOT_FOLDER}/
git add -A ${ROOT_FOLDER}/$file
fi
done
COMMIT_CHANGES="yes"
else
echo -e "Current branch is [${CURRENT_BRANCH}]"
# https://stackoverflow.com/questions/29300806/a-bash-script-to-check-if-a-string-is-present-in-a-comma-separated-list-of-strin
if [[ ",${ALLOWED_BRANCHES_VALUE}," = *",${CURRENT_BRANCH},"* ]] ; then
mkdir -p ${ROOT_FOLDER}/${CURRENT_BRANCH}
echo -e "Branch [${CURRENT_BRANCH}] is allowed! Will copy the current docs to the [${CURRENT_BRANCH}] folder"
for f in docs/target/generated-docs/*; do
file=${f#docs/target/generated-docs/*}
if ! git ls-files -i -o --exclude-standard --directory | grep -q ^$file$; then
# Not ignored...
# We want users to access 1.0.0.RELEASE/ instead of 1.0.0.RELEASE/spring-cloud.sleuth.html
if [[ "${file}" == "${MAIN_ADOC_VALUE}.html" ]] ; then
# We don't want to copy the spring-cloud-sleuth.html
# we want it to be converted to index.html
cp -rf $f ${ROOT_FOLDER}/${CURRENT_BRANCH}/index.html
git add -A ${ROOT_FOLDER}/${CURRENT_BRANCH}/index.html
else
cp -rf $f ${ROOT_FOLDER}/${CURRENT_BRANCH}
git add -A ${ROOT_FOLDER}/${CURRENT_BRANCH}/$file
fi
fi
done
COMMIT_CHANGES="yes"
else
echo -e "Branch [${CURRENT_BRANCH}] is not on the allow list! Check out the Maven [${ALLOW_PROPERTY}] property in
[docs] module available under [docs] profile. Won't commit any changes to gh-pages for this branch."
fi
fi
}
# Copies the docs by using the explicitly provided version
function copy_docs_for_provided_version() {
local FOLDER=${DESTINATION_REPO_FOLDER}/${VERSION}
mkdir -p ${FOLDER}
echo -e "Current tag is [v${VERSION}] Will copy the current docs to the [${FOLDER}] folder"
for f in ${ROOT_FOLDER}/docs/target/generated-docs/*; do
file=${f#${ROOT_FOLDER}/docs/target/generated-docs/*}
copy_docs_for_branch ${file} ${FOLDER}
done
COMMIT_CHANGES="yes"
CURRENT_BRANCH="v${VERSION}"
}
# Copies the docs from target to the provided destination
# Params:
# $1 - file from target
# $2 - destination to which copy the files
function copy_docs_for_branch() {
local file=$1
local destination=$2
if ! git ls-files -i -o --exclude-standard --directory | grep -q ^${file}$; then
# Not ignored...
# We want users to access 1.0.0.RELEASE/ instead of 1.0.0.RELEASE/spring-cloud.sleuth.html
if [[ ("${file}" == "${MAIN_ADOC_VALUE}.html") || ("${file}" == "${REPO_NAME}.html") ]] ; then
# We don't want to copy the spring-cloud-sleuth.html
# we want it to be converted to index.html
cp -rf $f ${destination}/index.html
git add -A ${destination}/index.html
else
cp -rf $f ${destination}
git add -A ${destination}/$file
fi
fi
}
function commit_changes_if_applicable() {
if [[ "${COMMIT_CHANGES}" == "yes" ]] ; then
COMMIT_SUCCESSFUL="no"
git commit -a -m "Sync docs from ${CURRENT_BRANCH} to gh-pages" && COMMIT_SUCCESSFUL="yes" || echo "Failed to commit changes"
# Uncomment the following push if you want to auto push to
# the gh-pages branch whenever you commit to master locally.
# This is a little extreme. Use with care!
###################################################################
if [[ "${COMMIT_SUCCESSFUL}" == "yes" ]] ; then
git push origin gh-pages
fi
fi
}
# Switch back to the previous branch and exit block
function checkout_previous_branch() {
# If -version was provided we need to come back to root project
cd ${ROOT_FOLDER}
git checkout ${CURRENT_BRANCH} || echo "Failed to check the branch... continuing with the script"
if [ "$dirty" != "0" ]; then git stash pop; fi
exit 0
}
# Assert if properties have been properly passed
function assert_properties() {
echo "VERSION [${VERSION}], DESTINATION [${DESTINATION}], CLONE [${CLONE}]"
if [[ "${VERSION}" != "" && (-z "${DESTINATION}" && -z "${CLONE}") ]] ; then echo "Version was set but destination / clone was not!"; exit 1;fi
if [[ ("${DESTINATION}" != "" && "${CLONE}" != "") && -z "${VERSION}" ]] ; then echo "Destination / clone was set but version was not!"; exit 1;fi
if [[ "${DESTINATION}" != "" && "${CLONE}" == "yes" ]] ; then echo "Destination and clone was set. Pick one!"; exit 1;fi
}
# Prints the usage
function print_usage() {
cat <<EOF
The idea of this script is to update gh-pages branch with the generated docs. Without any options
the script will work in the following manner:
- if there's no gh-pages / target for docs module then the script ends
- for main branch the generated docs are copied to the root of gh-pages branch
- for any other branch (if that branch is allowed) a subfolder with branch name is created
and docs are copied there
- if the version switch is passed (-v) then a tag with (v) prefix will be retrieved and a folder
with that version number will be created in the gh-pages branch. WARNING! No allow verification will take place
- if the destination switch is passed (-d) then the script will check if the provided dir is a git repo and then will
switch to gh-pages of that repo and copy the generated docs to `docs/<project-name>/<version>`
- if the destination switch is passed (-d) then the script will check if the provided dir is a git repo and then will
switch to gh-pages of that repo and copy the generated docs to `docs/<project-name>/<version>`
USAGE:
You can use the following options:
-v|--version - the script will apply the whole procedure for a particular library version
-d|--destination - the root of destination folder where the docs should be copied. You have to use the full path.
E.g. point to spring-cloud-static folder. Can't be used with (-c)
-b|--build - will run the standard build process after checking out the branch
-c|--clone - will automatically clone the spring-cloud-static repo instead of providing the destination.
Obviously can't be used with (-d)
EOF
}
# ==========================================
# ____ ____ _____ _____ _____ _______
# / ____|/ ____| __ \|_ _| __ \__ __|
# | (___ | | | |__) | | | | |__) | | |
# \___ \| | | _ / | | | ___/ | |
# ____) | |____| | \ \ _| |_| | | |
# |_____/ \_____|_| \_\_____|_| |_|
#
# ==========================================
while [[ $# > 0 ]]
do
key="$1"
case ${key} in
-v|--version)
VERSION="$2"
shift # past argument
;;
-d|--destination)
DESTINATION="$2"
shift # past argument
;;
-b|--build)
BUILD="yes"
;;
-c|--clone)
CLONE="yes"
;;
-h|--help)
print_usage
exit 0
;;
*)
echo "Invalid option: [$1]"
print_usage
exit 1
;;
esac
shift # past argument or value
done
assert_properties
set_default_props
check_if_anything_to_sync
if [[ -z "${VERSION}" ]] ; then
retrieve_current_branch
else
switch_to_tag
fi
build_docs_if_applicable
retrieve_doc_properties
stash_changes
add_docs_from_target
checkout_previous_branch

1
docs/src/main/asciidoc/index.adoc

@ -1 +0,0 @@ @@ -1 +0,0 @@
include::spring-cloud-commons.adoc[]

8
docs/src/main/asciidoc/jce.adoc

@ -1,8 +0,0 @@ @@ -1,8 +0,0 @@
If you get an exception due to "Illegal key size" and you use Sun's JDK, you need to install the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files.
See the following links for more information:
* https://www.oracle.com/technetwork/java/javase/downloads/jce-6-download-429243.html[Java 6 JCE]
* https://www.oracle.com/technetwork/java/javase/downloads/jce-7-download-432124.html[Java 7 JCE]
* https://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html[Java 8 JCE]
Extract the files into the JDK/jre/lib/security folder for whichever version of JRE/JDK x64/x86 you use.

1478
docs/src/main/asciidoc/spring-cloud-commons.adoc

File diff suppressed because it is too large Load Diff
Loading…
Cancel
Save