From c343b0ceec13e8df605c69b01364b56cd891c85f Mon Sep 17 00:00:00 2001
From: Spencer Gibb <spencer@gibb.us>
Date: Mon, 9 Jul 2018 13:09:26 -0400
Subject: [PATCH] Checks for null value if query parameter does not have a
 value

fixes gh-423
---
 .../handler/predicate/QueryRoutePredicateFactory.java  |  2 +-
 .../predicate/QueryRoutePredicateFactoryTests.java     | 10 ++++++++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactory.java b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactory.java
index fb203a10..c7e38ccb 100644
--- a/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactory.java
+++ b/spring-cloud-gateway-core/src/main/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactory.java
@@ -58,7 +58,7 @@ public class QueryRoutePredicateFactory extends AbstractRoutePredicateFactory<Qu
 				return false;
 			}
 			for (String value : values) {
-				if (value.matches(config.regexp)) {
+				if (value != null && value.matches(config.regexp)) {
 					return true;
 				}
 			}
diff --git a/spring-cloud-gateway-core/src/test/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactoryTests.java b/spring-cloud-gateway-core/src/test/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactoryTests.java
index 600df02e..f97e08e4 100644
--- a/spring-cloud-gateway-core/src/test/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactoryTests.java
+++ b/spring-cloud-gateway-core/src/test/java/org/springframework/cloud/gateway/handler/predicate/QueryRoutePredicateFactoryTests.java
@@ -64,6 +64,16 @@ public class QueryRoutePredicateFactoryTests extends BaseWebClientTests {
 				.expectHeader().valueEquals(ROUTE_ID_HEADER, "foo_query_param");;
 	}
 
+	@Test
+	public void emptyQueryParamWorks() {
+		testClient.get().uri("/get?foo")
+				.exchange()
+				.expectStatus().isOk()
+				.expectHeader().valueEquals(ROUTE_ID_HEADER, "default_path_to_httpbin");;
+
+		output.expect(not(containsString("Error applying predicate for route: foo_query_param")));
+	}
+
 	@EnableAutoConfiguration
 	@SpringBootConfiguration
 	@Import(DefaultTestConfig.class)