Get overrideScheme from isSecure(). (#2003)

spring-cloud-gateway-server/src/main/java/org/springframework/cloud/gateway/filter/ReactiveLoadBalancerClientFilter.java

@@ -94,17 +94,19 @@ public class ReactiveLoadBalancerClientFilter implements GlobalFilter, Ordered {
 						"Unable to find instance for " + url.getHost());
 			}
 
+			ServiceInstance retrievedInstance = response.getServer();
+
 			URI uri = exchange.getRequest().getURI();
 
 			// if the `lb:<scheme>` mechanism was used, use `<scheme>` as the default,
 			// if the loadbalancer doesn't provide one.
-			String overrideScheme = null;
+			String overrideScheme = retrievedInstance.isSecure() ? "https" : "http";
 			if (schemePrefix != null) {
 				overrideScheme = url.getScheme();
 			}
 
 			DelegatingServiceInstance serviceInstance = new DelegatingServiceInstance(
-					response.getServer(), overrideScheme);
+					retrievedInstance, overrideScheme);
 
 			URI requestUrl = reconstructURI(serviceInstance, uri);
 

spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/filter/ReactiveLoadBalancerClientFilterTests.java

@@ -35,6 +35,7 @@ import org.springframework.cloud.gateway.support.NotFoundException;
 import org.springframework.cloud.loadbalancer.core.ReactorServiceInstanceLoadBalancer;
 import org.springframework.cloud.loadbalancer.core.RoundRobinLoadBalancer;
 import org.springframework.cloud.loadbalancer.support.LoadBalancerClientFactory;
+import org.springframework.cloud.loadbalancer.support.ServiceInstanceListSuppliers;
 import org.springframework.cloud.loadbalancer.support.ServiceInstanceSuppliers;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
@@ -262,6 +263,31 @@ public class ReactiveLoadBalancerClientFilterTests {
 		}
 	}
 
+	@SuppressWarnings("unchecked")
+	@Test
+	public void shouldOverrideSchemeUsingIsSecure() {
+		URI url = UriComponentsBuilder.fromUriString("lb://myservice").build().toUri();
+		ServerWebExchange exchange = MockServerWebExchange
+				.from(MockServerHttpRequest.get("https://localhost:9999/mypath").build());
+		exchange.getAttributes().put(GATEWAY_REQUEST_URL_ATTR, url);
+		ServiceInstance serviceInstance = new DefaultServiceInstance("myservice1",
+				"myservice", "localhost", 8080, false);
+		when(clientFactory.getInstance("myservice",
+				ReactorServiceInstanceLoadBalancer.class)).thenReturn(
+				new RoundRobinLoadBalancer(ServiceInstanceListSuppliers
+						.toProvider("myservice", serviceInstance), "myservice", -1));
+		when(chain.filter(exchange)).thenReturn(Mono.empty());
+
+		filter.filter(exchange, chain).block();
+
+		assertThat((LinkedHashSet<URI>) exchange
+				.getAttribute(GATEWAY_ORIGINAL_REQUEST_URL_ATTR)).contains(url);
+		assertThat((URI) exchange.getAttribute(GATEWAY_REQUEST_URL_ATTR))
+				.isEqualTo(URI.create("http://localhost:8080/mypath"));
+		verify(chain).filter(exchange);
+		verifyNoMoreInteractions(chain);
+	}
+
 	private ServerWebExchange testFilter(MockServerHttpRequest request, URI uri) {
 		return testFilter(MockServerWebExchange.from(request), uri);
 	}