From b3a5dab1c8f1486a7362a771aa0ea65b8d87f833 Mon Sep 17 00:00:00 2001
From: Spencer Gibb <spencer@gibb.us>
Date: Wed, 16 Nov 2016 16:53:15 -0700
Subject: [PATCH] copy headers and add filters.

---
 .../cloud/gateway/GatewayController.java      | 27 +++++++++--------
 .../SpringCloudGatewayApplication.java        | 29 +++++++++++++++++++
 2 files changed, 42 insertions(+), 14 deletions(-)

diff --git a/src/main/java/org/springframework/cloud/gateway/GatewayController.java b/src/main/java/org/springframework/cloud/gateway/GatewayController.java
index ed6fe95e..896ca641 100644
--- a/src/main/java/org/springframework/cloud/gateway/GatewayController.java
+++ b/src/main/java/org/springframework/cloud/gateway/GatewayController.java
@@ -1,9 +1,8 @@
 package org.springframework.cloud.gateway;
 
-import org.springframework.core.io.buffer.DataBufferFactory;
-import org.springframework.core.io.buffer.DefaultDataBufferFactory;
-import org.springframework.http.MediaType;
-import org.springframework.http.client.reactive.ReactorClientHttpConnector;
+import java.util.Optional;
+
+import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.http.server.reactive.ServerHttpResponse;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
@@ -20,26 +19,26 @@ import reactor.core.publisher.Flux;
 public class GatewayController {
 
 	private final WebClient webClient;
-	private final DataBufferFactory bufferFactory;
 
-	public GatewayController() {
-		webClient = WebClient.builder(new ReactorClientHttpConnector()).build();
-		bufferFactory = new DefaultDataBufferFactory();
+	public GatewayController(WebClient webClient) {
+		this.webClient = webClient;
 	}
 
+	//TODO: plugin to request mappings
 	@GetMapping(path = "/")
 	public Flux<Void> home(ServerWebExchange exchange) {
-		ClientRequest<Void> request = ClientRequest
-				.GET("http://httpbin.org/get")
-				.accept(MediaType.APPLICATION_JSON)
+		Optional<String> requestUrl = exchange.getAttribute("requestUrl");
+		ServerHttpRequest request = exchange.getRequest();
+		ClientRequest<Void> clientRequest = ClientRequest
+				.method(request.getMethod(), requestUrl.get())
+				.headers(request.getHeaders())
 				.build();
 
-		return this.webClient.exchange(request).flatMap(clientResponse -> {
+		return this.webClient.exchange(clientRequest).flatMap(clientResponse -> {
 			ServerHttpResponse response = exchange.getResponse();
-			response.getHeaders().setContentType(clientResponse.headers().contentType().get());
+			response.getHeaders().putAll(clientResponse.headers().asHttpHeaders());
 			response.setStatusCode(clientResponse.statusCode());
 			return response.writeWith(clientResponse.body((inputMessage, context) -> inputMessage.getBody()));
-			// return response;
 		});
 	}
 }
diff --git a/src/main/java/org/springframework/cloud/gateway/SpringCloudGatewayApplication.java b/src/main/java/org/springframework/cloud/gateway/SpringCloudGatewayApplication.java
index 589fbc52..b2f9e499 100644
--- a/src/main/java/org/springframework/cloud/gateway/SpringCloudGatewayApplication.java
+++ b/src/main/java/org/springframework/cloud/gateway/SpringCloudGatewayApplication.java
@@ -2,10 +2,39 @@ package org.springframework.cloud.gateway;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.core.annotation.Order;
+import org.springframework.http.client.reactive.ReactorClientHttpConnector;
+import org.springframework.web.client.reactive.WebClient;
+import org.springframework.web.server.WebFilter;
 
 @SpringBootApplication
 public class SpringCloudGatewayApplication {
 
+	@Bean
+	public WebClient webClient() {
+		return WebClient.builder(new ReactorClientHttpConnector()).build();
+	}
+
+	// TODO: request only, how to filter response?
+	@Bean
+	@Order(500)
+	public WebFilter findRouteFilter() {
+		return (exchange, chain) -> {
+			exchange.getAttributes().put("requestUrl", "http://httpbin.org/get");
+			return chain.filter(exchange);
+		};
+	}
+
+	@Bean
+	@Order(501)
+	public WebFilter modifyResponseFilter() {
+		return (exchange, chain) -> {
+			exchange.getResponse().getHeaders().add("X-My-Custom", "MyCustomValue");
+			return chain.filter(exchange);
+		};
+	}
+
 	public static void main(String[] args) {
 		SpringApplication.run(SpringCloudGatewayApplication.class, args);
 	}