Prefix path uses path variables.

Fixes gh-2438
Fixes gh-2578

.github/workflows/maven.yml

@@ -29,7 +29,7 @@ jobs:
           restore-keys: |
             ${{ runner.os }}-maven-
       - name: Build with Maven
-        run: ./mvnw clean install -B -U -Pspring -Dmaven.test.redirectTestOutputToFile=true
+        run: ./mvnw clean install -B -U -Pspring -Dmaven.test.redirectTestOutputToFile=true -Dmaven.wagon.httpconnectionManager.ttlSeconds=120
       - name: Publish Test Report
         uses: mikepenz/action-junit-report@v2
         if: always() # always run even if the previous step fails

spring-cloud-gateway-server/src/main/java/org/springframework/cloud/gateway/filter/factory/PrefixPathGatewayFilterFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2020 the original author or authors.
+ * Copyright 2013-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,8 +16,10 @@
 
 package org.springframework.cloud.gateway.filter.factory;
 
+import java.net.URI;
 import java.util.Arrays;
 import java.util.List;
+import java.util.Map;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -27,11 +29,13 @@ import org.springframework.cloud.gateway.filter.GatewayFilter;
 import org.springframework.cloud.gateway.filter.GatewayFilterChain;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.util.UriTemplate;
 
 import static org.springframework.cloud.gateway.support.GatewayToStringStyler.filterToStringCreator;
 import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_ALREADY_PREFIXED_ATTR;
 import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR;
 import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.addOriginalRequestUrl;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.getUriTemplateVariables;
 
 /**
  * @author Spencer Gibb
@@ -58,6 +62,8 @@ public class PrefixPathGatewayFilterFactory
 	@Override
 	public GatewayFilter apply(Config config) {
 		return new GatewayFilter() {
+			final UriTemplate uriTemplate = new UriTemplate(config.prefix);
+
 			@Override
 			public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
 				boolean alreadyPrefixed = exchange.getAttributeOrDefault(GATEWAY_ALREADY_PREFIXED_ATTR, false);
@@ -68,11 +74,13 @@ public class PrefixPathGatewayFilterFactory
 
 				ServerHttpRequest req = exchange.getRequest();
 				addOriginalRequestUrl(exchange, req.getURI());
-				String newPath = config.prefix + req.getURI().getRawPath();
 
-				ServerHttpRequest request = req.mutate().path(newPath).build();
+				Map<String, String> uriVariables = getUriTemplateVariables(exchange);
+				URI uri = uriTemplate.expand(uriVariables);
 
-				exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, request.getURI());
+				String newPath = uri.getRawPath() + req.getURI().getRawPath();
+				exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, uri);
+				ServerHttpRequest request = req.mutate().path(newPath).build();
 
 				if (log.isTraceEnabled()) {
 					log.trace("Prefixed URI with: " + config.prefix + " -> " + request.getURI());

spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/filter/factory/PrefixPathGatewayFilterFactoryTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2013-2020 the original author or authors.
+ * Copyright 2013-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,6 +17,7 @@
 package org.springframework.cloud.gateway.filter.factory;
 
 import java.net.URI;
+import java.util.HashMap;
 import java.util.LinkedHashSet;
 
 import org.junit.Test;
@@ -26,6 +27,7 @@ import reactor.core.publisher.Mono;
 import org.springframework.cloud.gateway.filter.GatewayFilter;
 import org.springframework.cloud.gateway.filter.GatewayFilterChain;
 import org.springframework.cloud.gateway.filter.factory.PrefixPathGatewayFilterFactory.Config;
+import org.springframework.cloud.gateway.support.ServerWebExchangeUtils;
 import org.springframework.mock.http.server.reactive.MockServerHttpRequest;
 import org.springframework.mock.web.server.MockServerWebExchange;
 import org.springframework.web.server.ServerWebExchange;
@@ -46,11 +48,33 @@ public class PrefixPathGatewayFilterFactoryTest {
 		testPrefixPathFilter("/foo", "/hello%20world", "/foo/hello%20world");
 	}
 
+	@Test
+	public void testPrefixPathWithVariable() {
+		HashMap<String, String> variables = new HashMap<>();
+		variables.put("id", "foo");
+		testPrefixPathFilter("/{id}", "/bar", "/foo/bar", variables);
+	}
+
+	@Test
+	public void testPrefixPathWithMultipleVariables() {
+		HashMap<String, String> variables = new HashMap<>();
+		variables.put("id", "foo");
+		variables.put("hello", "world");
+		variables.put("product", "bar");
+		testPrefixPathFilter("/{id}/v1/{hello}/{product}", "/test", "/foo/v1/world/bar/test", variables);
+	}
+
 	private void testPrefixPathFilter(String prefix, String path, String expectedPath) {
+		testPrefixPathFilter(prefix, path, expectedPath, new HashMap<>());
+	}
+
+	private void testPrefixPathFilter(String prefix, String path, String expectedPath,
+			HashMap<String, String> variables) {
 		GatewayFilter filter = new PrefixPathGatewayFilterFactory().apply(c -> c.setPrefix(prefix));
 		MockServerHttpRequest request = MockServerHttpRequest.get("http://localhost" + path).build();
 
 		ServerWebExchange exchange = MockServerWebExchange.from(request);
+		ServerWebExchangeUtils.putUriTemplateVariables(exchange, variables);
 
 		GatewayFilterChain filterChain = mock(GatewayFilterChain.class);