Merge branch '2.0.x'

spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/filter/headers/XForwardedHeadersFilter.java

@@ -17,8 +17,9 @@
 
 package org.springframework.cloud.gateway.filter.headers;
 
+import java.net.URI;
+import java.util.LinkedHashSet;
 import java.util.List;
-
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.core.Ordered;
 import org.springframework.http.HttpHeaders;
@@ -26,6 +27,9 @@ import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.util.StringUtils;
 import org.springframework.web.server.ServerWebExchange;
 
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_ORIGINAL_REQUEST_URL_ATTR;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR;
+
 @ConfigurationProperties("spring.cloud.gateway.x-forwarded")
 public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 	/** default http port */
@@ -52,6 +56,10 @@ public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 	/** X-Forwarded-Proto Header */
 	public static final String X_FORWARDED_PROTO_HEADER = "X-Forwarded-Proto";
 
+	/** X-Forwarded-Prefix Header */
+	public static final String X_FORWARDED_PREFIX_HEADER = "X-Forwarded-Prefix";
+
+
 	/** The order of the XForwardedHeadersFilter. */
 	private int order = 0;
 
@@ -70,6 +78,9 @@ public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 	/** If X-Forwarded-Proto is enabled. */
 	private boolean protoEnabled = true;
 
+	/** If X-Forwarded-Prefix is enabled. */
+	private boolean prefixEnabled = true;
+
 	/** If appending X-Forwarded-For as a list is enabled. */
 	private boolean forAppend = true;
 
@@ -82,6 +93,9 @@ public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 	/** If appending X-Forwarded-Proto as a list is enabled. */
 	private boolean protoAppend = true;
 
+	/** If appending X-Forwarded-Prefix as a list is enabled. */
+	private boolean prefixAppend = true;
+
 	@Override
 	public int getOrder() {
 		return this.order;
@@ -131,6 +145,14 @@ public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 		this.protoEnabled = protoEnabled;
 	}
 
+	public boolean isPrefixEnabled() {
+		return prefixEnabled;
+	}
+
+	public void setPrefixEnabled(boolean prefixEnabled) {
+		this.prefixEnabled = prefixEnabled;
+	}
+
 	public boolean isForAppend() {
 		return forAppend;
 	}
@@ -163,8 +185,18 @@ public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 		this.protoAppend = protoAppend;
 	}
 
+	public void setPrefixAppend(boolean prefixAppend) {
+		this.prefixAppend = prefixAppend;
+	}
+
+	public boolean isPrefixAppend() {
+		return prefixAppend;
+	}
+
 	@Override
 	public HttpHeaders filter(HttpHeaders input, ServerWebExchange exchange) {
+
+
 		ServerHttpRequest request = exchange.getRequest();
 		HttpHeaders original = input;
 		HttpHeaders updated = new HttpHeaders();
@@ -189,6 +221,37 @@ public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 			write(updated, X_FORWARDED_PROTO_HEADER, proto, isProtoAppend());
 		}
 
+		if(isPrefixEnabled()) {
+			//if the path of the url that the gw is routing to is a subset (and ending part) of the url that it is routing from then the difference is the prefix
+			//e.g. if request original.com/prefix/get/ is routed to routedservice:8090/get then /prefix is the prefix - see XForwardedHeadersFilterTests
+			//so first get uris, then extract paths and remove one from another if it's the ending part
+
+			LinkedHashSet<URI> originalUris = exchange.getAttribute(GATEWAY_ORIGINAL_REQUEST_URL_ATTR);
+			URI requestUri = exchange.getAttribute(GATEWAY_REQUEST_URL_ATTR);
+
+			if(originalUris != null && requestUri != null) {
+
+				originalUris.stream().forEach(originalUri -> {
+
+					if(originalUri!=null && originalUri.getPath()!=null) {
+						String prefix = originalUri.getPath();
+
+						//strip trailing slashes before checking if request path is end of original path
+						String originalUriPath = stripTrailingSlash(originalUri);
+						String requestUriPath = stripTrailingSlash(requestUri);
+
+						if(requestUriPath!=null && (originalUriPath.endsWith(requestUriPath))) {
+							prefix = originalUriPath.replace(requestUriPath, "");
+						}
+						if (prefix != null && prefix.length() > 0 &&
+								prefix.length() < originalUri.getPath().length()) {
+							write(updated, X_FORWARDED_PREFIX_HEADER, prefix, isPrefixAppend());
+						}
+					}
+				});
+			}
+		}
+
 		if (isPortEnabled()) {
 			String port = String.valueOf(request.getURI().getPort());
 			if (request.getURI().getPort() < 0) {
@@ -240,4 +303,12 @@ public class XForwardedHeadersFilter implements HttpHeadersFilter, Ordered {
 			return host + ":" + port;
 		}
 	}
-}
+
+	private String stripTrailingSlash(URI uri) {
+		if (uri.getPath().endsWith("/")) {
+			return uri.getPath().substring(0, uri.getPath().length() - 1);
+		} else {
+			return uri.getPath();
+		}
+	}
+}

spring-cloud-gateway-core/src/test/java/org/springframework/cloud/gateway/filter/headers/XForwardedHeadersFilterTests.java

@@ -19,18 +19,25 @@ package org.springframework.cloud.gateway.filter.headers;
 
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
+import java.net.URI;
+import java.util.LinkedHashSet;
 
 import org.junit.Test;
 
 import org.springframework.http.HttpHeaders;
 import org.springframework.mock.http.server.reactive.MockServerHttpRequest;
 import org.springframework.mock.web.server.MockServerWebExchange;
+import org.springframework.web.server.ServerWebExchange;
+import org.springframework.web.util.UriComponentsBuilder;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.springframework.cloud.gateway.filter.headers.XForwardedHeadersFilter.X_FORWARDED_FOR_HEADER;
 import static org.springframework.cloud.gateway.filter.headers.XForwardedHeadersFilter.X_FORWARDED_HOST_HEADER;
 import static org.springframework.cloud.gateway.filter.headers.XForwardedHeadersFilter.X_FORWARDED_PORT_HEADER;
+import static org.springframework.cloud.gateway.filter.headers.XForwardedHeadersFilter.X_FORWARDED_PREFIX_HEADER;
 import static org.springframework.cloud.gateway.filter.headers.XForwardedHeadersFilter.X_FORWARDED_PROTO_HEADER;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_ORIGINAL_REQUEST_URL_ATTR;
+import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR;
 
 /**
  * @author Spencer Gibb
@@ -131,6 +138,7 @@ public class XForwardedHeadersFilterTests {
 				.header(X_FORWARDED_HOST_HEADER, "example.com")
 				.header(X_FORWARDED_PORT_HEADER, "443")
 				.header(X_FORWARDED_PROTO_HEADER, "https")
+				.header(X_FORWARDED_PREFIX_HEADER,"/prefix")
 				.build();
 
 		XForwardedHeadersFilter filter = new XForwardedHeadersFilter();
@@ -138,16 +146,98 @@ public class XForwardedHeadersFilterTests {
 		filter.setHostAppend(false);
 		filter.setPortAppend(false);
 		filter.setProtoAppend(false);
+		filter.setPrefixAppend(false);
 
 		HttpHeaders headers = filter.filter(request.getHeaders(), MockServerWebExchange.from(request));
 
 		assertThat(headers).containsKeys(X_FORWARDED_FOR_HEADER, X_FORWARDED_HOST_HEADER,
-				X_FORWARDED_PORT_HEADER, X_FORWARDED_PROTO_HEADER);
+				X_FORWARDED_PORT_HEADER, X_FORWARDED_PROTO_HEADER,X_FORWARDED_PREFIX_HEADER);
 
 		assertThat(headers.getFirst(X_FORWARDED_FOR_HEADER)).isEqualTo("10.0.0.1");
 		assertThat(headers.getFirst(X_FORWARDED_HOST_HEADER)).isEqualTo("localhost:8080");
 		assertThat(headers.getFirst(X_FORWARDED_PORT_HEADER)).isEqualTo("8080");
 		assertThat(headers.getFirst(X_FORWARDED_PROTO_HEADER)).isEqualTo("http");
+		assertThat(headers.getFirst(X_FORWARDED_PREFIX_HEADER)).isEqualTo("/prefix");
+	}
+
+
+	@Test
+	public void prefixToInfer() throws Exception {
+		MockServerHttpRequest request = MockServerHttpRequest
+				.get("http://originalhost:8080/prefix/get")
+				.remoteAddress(new InetSocketAddress(InetAddress.getByName("10.0.0.1"), 80))
+				.build();
+
+		XForwardedHeadersFilter filter = new XForwardedHeadersFilter();
+		filter.setPrefixAppend(true);
+		filter.setPrefixEnabled(true);
+
+		ServerWebExchange exchange = MockServerWebExchange.from(request);
+		LinkedHashSet<URI> originalUris = new LinkedHashSet<>();
+		originalUris.add(UriComponentsBuilder.fromUriString("http://originalhost:8080/prefix/get/").build().toUri()); //trailing slash
+		exchange.getAttributes().put(GATEWAY_ORIGINAL_REQUEST_URL_ATTR, originalUris);
+		URI requestUri = UriComponentsBuilder.fromUriString("http://routedservice:8090/get").build().toUri();
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, requestUri);
+
+		HttpHeaders headers = filter.filter(request.getHeaders(), exchange);
+
+		assertThat(headers).containsKeys(X_FORWARDED_PREFIX_HEADER);
+
+		assertThat(headers.getFirst(X_FORWARDED_PREFIX_HEADER)).isEqualTo("/prefix");
+	}
+
+	@Test
+	public void noPrefixToInfer() throws Exception {
+		MockServerHttpRequest request = MockServerHttpRequest
+				.get("http://originalhost:8080/get")
+				.remoteAddress(new InetSocketAddress(InetAddress.getByName("10.0.0.1"), 80))
+				.build();
+
+		XForwardedHeadersFilter filter = new XForwardedHeadersFilter();
+		filter.setPrefixAppend(true);
+		filter.setPrefixEnabled(true);
+		filter.setForEnabled(false);
+		filter.setHostEnabled(false);
+		filter.setPortEnabled(false);
+		filter.setProtoEnabled(false);
+
+		ServerWebExchange exchange = MockServerWebExchange.from(request);
+		LinkedHashSet<URI> originalUris = new LinkedHashSet<>();
+		originalUris.add(UriComponentsBuilder.fromUriString("http://originalhost:8080/get/").build().toUri());
+		exchange.getAttributes().put(GATEWAY_ORIGINAL_REQUEST_URL_ATTR, originalUris);
+		URI requestUri = UriComponentsBuilder.fromUriString("http://routedservice:8090/get").build().toUri();
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, requestUri);
+
+		HttpHeaders headers = filter.filter(request.getHeaders(), exchange);
+
+		assertThat(headers).isEmpty();
+	}
+
+	@Test
+	public void routedPathInRequestPathButNotPrefix() throws Exception {
+		MockServerHttpRequest request = MockServerHttpRequest
+				.get("http://originalhost:8080/get")
+				.remoteAddress(new InetSocketAddress(InetAddress.getByName("10.0.0.1"), 80))
+				.build();
+
+		XForwardedHeadersFilter filter = new XForwardedHeadersFilter();
+		filter.setPrefixAppend(true);
+		filter.setPrefixEnabled(true);
+		filter.setForEnabled(false);
+		filter.setHostEnabled(false);
+		filter.setPortEnabled(false);
+		filter.setProtoEnabled(false);
+
+		ServerWebExchange exchange = MockServerWebExchange.from(request);
+		LinkedHashSet<URI> originalUris = new LinkedHashSet<>();
+		originalUris.add(UriComponentsBuilder.fromUriString("http://originalhost:8080/one/two/three").build().toUri());
+		exchange.getAttributes().put(GATEWAY_ORIGINAL_REQUEST_URL_ATTR, originalUris);
+		URI requestUri = UriComponentsBuilder.fromUriString("http://routedservice:8090/two").build().toUri();
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, requestUri);
+
+		HttpHeaders headers = filter.filter(request.getHeaders(), exchange);
+
+		assertThat(headers).isEmpty();
 	}
 
 	@Test
@@ -162,6 +252,7 @@ public class XForwardedHeadersFilterTests {
 		filter.setHostEnabled(false);
 		filter.setPortEnabled(false);
 		filter.setProtoEnabled(false);
+		filter.setPrefixEnabled(false);
 
 		HttpHeaders headers = filter.filter(request.getHeaders(), MockServerWebExchange.from(request));