From ed5dd81beb089573390c0dd5376ec65d45677e66 Mon Sep 17 00:00:00 2001
From: Spencer Gibb <spencer@gibb.us>
Date: Sat, 18 Mar 2017 00:10:27 -0600
Subject: [PATCH] Adds more convenient filter methods

---
 .../cloud/gateway/route/Routes.java           | 71 +++++++++++++++----
 .../sample/GatewaySampleApplication.java      |  5 +-
 2 files changed, 59 insertions(+), 17 deletions(-)

diff --git a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/Routes.java b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/Routes.java
index b00fb5e3..2938d0c2 100644
--- a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/Routes.java
+++ b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/route/Routes.java
@@ -17,15 +17,17 @@
 
 package org.springframework.cloud.gateway.route;
 
-import org.springframework.web.reactive.function.server.RequestPredicate;
-import org.springframework.web.server.WebFilter;
-import reactor.core.publisher.Flux;
-
 import java.net.URI;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 
+import org.springframework.cloud.gateway.filter.factory.WebFilterFactories;
+import org.springframework.web.reactive.function.server.RequestPredicate;
+import org.springframework.web.server.WebFilter;
+
+import reactor.core.publisher.Flux;
+
 /**
  * @author Spencer Gibb
  */
@@ -66,37 +68,76 @@ public class Routes {
 			return this;
 		}
 
-		public RouteBuilder uri(String uri) {
+		public PredicateBuilder uri(String uri) {
 			this.builder.uri(uri);
-			return this;
+			return predicateBuilder();
 		}
 
-		public RouteBuilder uri(URI uri) {
+		public PredicateBuilder uri(URI uri) {
 			this.builder.uri(uri);
-			return this;
+			return predicateBuilder();
 		}
 
-		public RouteBuilder predicate(RequestPredicate predicate) {
-			this.builder.requestPredicate(predicate);
-			return this;
+		private PredicateBuilder predicateBuilder() {
+			return new PredicateBuilder(this.builder, this.locatorBuilder);
 		}
 
-		//TODO: maybe add WebFilterBuilder so no need to import WebFilterFactories?
-		public RouteBuilder webFilters(List<WebFilter> webFilters) {
+	}
+
+	public static class PredicateBuilder {
+
+		private final Route.Builder routeBuilder;
+		private LocatorBuilder locatorBuilder;
+
+		private PredicateBuilder(Route.Builder routeBuilder, LocatorBuilder locatorBuilder) {
+			this.routeBuilder = routeBuilder;
+			this.locatorBuilder = locatorBuilder;
+		}
+
+		/* TODO: has and, or & negate of RequestPredicate with terminal filters()?
+		public RequestPredicateBuilder host(String pattern) {
+			RequestPredicate requestPredicate = GatewayRequestPredicates.host(pattern);
+		}*/
+
+		public WebFilterBuilder predicate(RequestPredicate predicate) {
+			this.routeBuilder.requestPredicate(predicate);
+			return webFilterBuilder();
+		}
+
+		private WebFilterBuilder webFilterBuilder() {
+			return new WebFilterBuilder(this.routeBuilder, this.locatorBuilder);
+		}
+
+	}
+
+	public static class WebFilterBuilder {
+		private Route.Builder builder;
+		private LocatorBuilder locatorBuilder;
+
+		public WebFilterBuilder(Route.Builder routeBuilder, LocatorBuilder locatorBuilder) {
+			this.builder = routeBuilder;
+			this.locatorBuilder = locatorBuilder;
+		}
+
+		public WebFilterBuilder webFilters(List<WebFilter> webFilters) {
 			this.builder.webFilters(webFilters);
 			return this;
 		}
 
-		public RouteBuilder add(WebFilter webFilter) {
+		public WebFilterBuilder add(WebFilter webFilter) {
 			this.builder.add(webFilter);
 			return this;
 		}
 
-		public RouteBuilder addAll(Collection<WebFilter> webFilters) {
+		public WebFilterBuilder addAll(Collection<WebFilter> webFilters) {
 			this.builder.addAll(webFilters);
 			return this;
 		}
 
+		public WebFilterBuilder addResponseHeader(String headerName, String headerValue) {
+			return add(WebFilterFactories.addResponseHeader(headerName, headerValue));
+		}
+
 		public LocatorBuilder and() {
 			Route route = this.builder.build();
 			this.locatorBuilder.add(route);
diff --git a/spring-cloud-gateway-sample/src/main/java/org/springframework/cloud/gateway/sample/GatewaySampleApplication.java b/spring-cloud-gateway-sample/src/main/java/org/springframework/cloud/gateway/sample/GatewaySampleApplication.java
index 7c727fa1..8c6cc034 100644
--- a/spring-cloud-gateway-sample/src/main/java/org/springframework/cloud/gateway/sample/GatewaySampleApplication.java
+++ b/spring-cloud-gateway-sample/src/main/java/org/springframework/cloud/gateway/sample/GatewaySampleApplication.java
@@ -26,6 +26,7 @@ import org.springframework.cloud.gateway.route.Routes;
 import org.springframework.context.annotation.Bean;
 
 import static org.springframework.cloud.gateway.filter.factory.WebFilterFactories.addResponseHeader;
+import static org.springframework.cloud.gateway.handler.predicate.GatewayRequestPredicates.host;
 import static org.springframework.cloud.gateway.handler.predicate.GatewayRequestPredicates.path;
 // import static org.springframework.web.reactive.function.server.RequestPredicates.path;
 
@@ -42,8 +43,8 @@ public class GatewaySampleApplication {
 		return Routes.locator()
 				.route("test")
 					.uri("http://httpbin.org:80")
-					.predicate(path("/image/png"))
-					.add(addResponseHeader("X-TestHeader", "foobar"))
+					.predicate(host("**.abc.org").and(path("/image/png")))
+					.addResponseHeader("X-TestHeader", "foobar")
 					.and()
 				.route("test2")
 					.uri("http://httpbin.org:80")