Correct the order when routes are refreshed by group (#3112)

spring-cloud-gateway-server/src/main/java/org/springframework/cloud/gateway/route/CachingRouteLocator.java

@@ -88,8 +88,9 @@ public class CachingRouteLocator
 						.onErrorResume(s -> Mono.just(List.of()));
 
 				scopedRoutes.subscribe(scopedRoutesList -> {
-					Flux.concat(Flux.fromIterable(scopedRoutesList), getNonScopedRoutes(event)).materialize()
-							.collect(Collectors.toList()).subscribe(signals -> {
+					Flux.concat(Flux.fromIterable(scopedRoutesList), getNonScopedRoutes(event))
+							.sort(AnnotationAwareOrderComparator.INSTANCE).materialize().collect(Collectors.toList())
+							.subscribe(signals -> {
 								applicationEventPublisher.publishEvent(new RefreshRoutesResultEvent(this));
 								cache.put(CACHE_KEY, signals);
 							}, this::handleRefreshError);

spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/actuate/GatewayControllerEndpointTests.java

@@ -23,6 +23,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.UUID;
 import java.util.function.Predicate;
+import java.util.stream.Collectors;
 
 import org.assertj.core.util.Maps;
 import org.junit.jupiter.api.Assertions;
@@ -193,6 +194,62 @@ public class GatewayControllerEndpointTests {
 				});
 	}
 
+	@Test
+	public void testOrderOfRefreshByGroup() {
+		RouteDefinition testRouteDefinition = new RouteDefinition();
+		testRouteDefinition.setUri(URI.create("http://example.org"));
+		testRouteDefinition.setOrder(1000);
+		String group1 = "group-1_" + UUID.randomUUID();
+		testRouteDefinition.setMetadata(Map.of("groupBy", group1));
+
+		String routeId1 = "route-1_" + UUID.randomUUID();
+		testClient.post().uri("http://localhost:" + port + "/actuator/gateway/routes/" + routeId1)
+				.accept(MediaType.APPLICATION_JSON).body(BodyInserters.fromValue(testRouteDefinition)).exchange()
+				.expectStatus().isCreated();
+
+		RouteDefinition testRouteDefinition2 = new RouteDefinition();
+		testRouteDefinition2.setUri(URI.create("http://example.org"));
+		testRouteDefinition2.setOrder(0);
+		String group2 = "group-2_" + UUID.randomUUID();
+		testRouteDefinition2.setMetadata(Map.of("groupBy", group2));
+		String routeId2 = "route-2_" + UUID.randomUUID();
+		testClient.post().uri("http://localhost:" + port + "/actuator/gateway/routes/" + routeId2)
+				.accept(MediaType.APPLICATION_JSON).body(BodyInserters.fromValue(testRouteDefinition2)).exchange()
+				.expectStatus().isCreated();
+
+		testClient.post().uri("http://localhost:" + port + "/actuator/gateway/refresh?metadata=groupBy:" + group1)
+				.exchange().expectStatus().isOk();
+		testClient.post().uri("http://localhost:" + port + "/actuator/gateway/refresh?metadata=groupBy:" + group2)
+				.exchange().expectStatus().isOk();
+
+		testClient.get().uri("http://localhost:" + port + "/actuator/gateway/routes").exchange().expectStatus().isOk()
+				.expectBodyList(Map.class).consumeWith(result -> {
+					List<Map> responseBody = result.getResponseBody();
+
+					List ids = responseBody.stream()
+									.map(route -> route.get("route_id"))
+											.filter(id -> id.equals(routeId1) || id.equals(routeId2))
+													.collect(Collectors.toList());
+					assertThat(ids).containsExactly(routeId2, routeId1);
+				});
+
+		testRouteDefinition2.setOrder(testRouteDefinition.getOrder() + 1);
+		testClient.post().uri("http://localhost:" + port + "/actuator/gateway/routes/" + routeId2)
+				.accept(MediaType.APPLICATION_JSON).body(BodyInserters.fromValue(testRouteDefinition2)).exchange()
+				.expectStatus().isCreated();
+		testClient.post().uri("http://localhost:" + port + "/actuator/gateway/refresh?metadata=groupBy:" + group2)
+				.exchange().expectStatus().isOk();
+		testClient.get().uri("http://localhost:" + port + "/actuator/gateway/routes").exchange().expectStatus().isOk()
+				.expectBodyList(Map.class).consumeWith(result -> {
+					List<Map> responseBody = result.getResponseBody();
+					List ids = responseBody.stream()
+							.map(route -> route.get("route_id"))
+							.filter(id -> id.equals(routeId1) || id.equals(routeId2))
+							.collect(Collectors.toList());
+					assertThat(ids).containsExactly(routeId1, routeId2);
+				});
+	}
+
 	@Test
 	public void testRefreshByGroup_whenRouteDefinitionsAreDeleted() {
 		RouteDefinition testRouteDefinition = new RouteDefinition();