use URI rather than string

src/main/java/org/springframework/cloud/gateway/GatewayProperties.java

@@ -28,7 +28,8 @@ public class GatewayProperties {
 	public static class Route {
 		private String id;
 		private String path;
-		private String url;
+		private String host;
+		private String port;
 
 		public String getPath() {
 			return this.path;
@@ -38,12 +39,30 @@ public class GatewayProperties {
 			this.path = path;
 		}
 
-		public String getUrl() {
-			return this.url;
+		public String getHost() {
+			return this.host;
 		}
 
-		public void setUrl(String url) {
-			this.url = url;
+		public void setHost(String host) {
+			this.host = host;
+		}
+
+		public String getPort() {
+			return port;
+		}
+
+		public void setPort(String port) {
+			this.port = port;
+		}
+
+		@Override
+		public String toString() {
+			return "Route{" +
+					"id='" + id + '\'' +
+					", path='" + path + '\'' +
+					", host='" + host + '\'' +
+					", port='" + port + '\'' +
+					'}';
 		}
 	}
 }

src/main/java/org/springframework/cloud/gateway/GatewayWebHandler.java

@@ -10,6 +10,7 @@ import org.springframework.web.server.WebHandler;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
+import java.net.URI;
 import java.util.Optional;
 
 /**
@@ -27,7 +28,7 @@ public class GatewayWebHandler implements WebHandler {
 
 	@Override
 	public Mono<Void> handle(ServerWebExchange exchange) {
-		Optional<String> requestUrl = exchange.getAttribute("requestUrl");
+		Optional<URI> requestUrl = exchange.getAttribute("requestUri");
 		ServerHttpRequest request = exchange.getRequest();
 		ClientRequest<Void> clientRequest = ClientRequest
 				.method(request.getMethod(), requestUrl.get())

src/main/java/org/springframework/cloud/gateway/filters/FindRouteFilter.java

@@ -10,6 +10,7 @@ import org.springframework.util.AntPathMatcher;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.server.WebFilter;
 import org.springframework.web.server.WebFilterChain;
+import org.springframework.web.util.UriComponentsBuilder;
 import reactor.core.publisher.Mono;
 
 import java.net.URI;
@@ -38,8 +39,12 @@ public class FindRouteFilter implements WebFilter {
 		String path = uri.getPath();
 		for (Route route : this.properties.getRoutes().values()) {
 			if (this.matcher.match(route.getPath(), path)) {
-				String url = route.getUrl() + path;
-				exchange.getAttributes().put("requestUrl", url);
+				URI requestUri = UriComponentsBuilder.fromHttpRequest(request)
+						.host(route.getHost())
+						.port(route.getPort())
+						.build(true)
+						.toUri();
+				exchange.getAttributes().put("requestUri", requestUri);
 				return chain.filter(exchange);
 			}
 		}

src/main/resources/application.yml

@@ -7,4 +7,5 @@ spring:
       routes:
         test1:
           path: /**
-          url: http://httpbin.org
+          host: httpbin.org
+          port: 80