Encode query params in Zuul filter

Some slightly tricky manipulation involved here, but hopefully
UriTemplate to the rescue.

Fixes gh-682

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/ProxyRequestHelper.java

@@ -22,6 +22,7 @@ import java.io.InputStreamReader;
 import java.nio.charset.Charset;
 import java.util.Collection;
 import java.util.Enumeration;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
@@ -36,6 +37,7 @@ import org.springframework.boot.actuate.trace.TraceRepository;
 import org.springframework.http.HttpHeaders;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
+import org.springframework.web.util.UriTemplate;
 import org.springframework.web.util.UriUtils;
 import org.springframework.web.util.WebUtils;
 
@@ -290,17 +292,27 @@ public class ProxyRequestHelper {
 	}
 
 	public String getQueryString(MultiValueMap<String, String> params) {
+		if (params.isEmpty()) {
+			return "";
+		}
 		StringBuilder query = new StringBuilder();
+		Map<String, Object> singles = new HashMap<>();
 		for (String param : params.keySet()) {
+			int i = 0;
 			for (String value : params.get(param)) {
 				query.append("&");
 				query.append(param);
 				if (!"".equals(value)) {
-					query.append("=");
-					query.append(value);
+					singles.put(param + i, value);
+					query.append("={");
+					query.append(param + i);
+					query.append("}");
 				}
+				i++;
 			}
 		}
-		return (query.length() > 0) ? "?" + query.substring(1) : "";
+
+		UriTemplate template = new UriTemplate("?" + query.toString().substring(1));
+		return template.expand(singles).toString();
 	}
 }

spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/zuul/SampleZuulProxyApplicationTests.java

@@ -51,6 +51,7 @@ import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 import org.springframework.util.MultiValueMap;
 import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 
 import com.netflix.client.ClientException;
@@ -109,6 +110,28 @@ public class SampleZuulProxyApplicationTests extends ZuulProxyTestBase {
 				result.getHeaders().get("X-Application-Context").toString());
 	}
 
+	@Test
+	public void simpleHostRouteWithQuery() {
+		this.routes.addRoute("/self/**", "http://localhost:" + this.port + "/");
+		this.endpoint.reset();
+		ResponseEntity<String> result = new TestRestTemplate().exchange(
+				"http://localhost:" + this.port + "/self/query?foo=bar", HttpMethod.GET,
+				new HttpEntity<>((Void) null), String.class);
+		assertEquals(HttpStatus.OK, result.getStatusCode());
+		assertEquals("/query?foo=bar", result.getBody());
+	}
+
+	@Test
+	public void simpleHostRouteWithEncodedQuery() {
+		this.routes.addRoute("/self/**", "http://localhost:" + this.port + "/");
+		this.endpoint.reset();
+		ResponseEntity<String> result = new TestRestTemplate().exchange(
+				"http://localhost:" + this.port + "/self/query?foo={foo}", HttpMethod.GET,
+				new HttpEntity<>((Void) null), String.class, "weird#chars");
+		assertEquals(HttpStatus.OK, result.getStatusCode());
+		assertEquals("/query?foo=weird#chars", result.getBody());
+	}
+
 	@Test
 	public void ribbonCommandForbidden() {
 		ResponseEntity<String> result = new TestRestTemplate().exchange(
@@ -166,6 +189,11 @@ class SampleZuulProxyApplication extends ZuulProxyTestBase.AbstractZuulProxyAppl
 		return result;
 	}
 
+	@RequestMapping(value = "/query")
+	public String addQuery(HttpServletRequest request, @RequestParam String foo) {
+		return request.getRequestURI() + "?foo=" + foo;
+	}
+
 	@Bean
 	public RibbonCommandFactory<?> ribbonCommandFactory(
 			SpringClientFactory clientFactory) {

spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/zuul/ZuulProxyTestBase.java

@@ -54,8 +54,8 @@ public abstract class ZuulProxyTestBase {
 
 	@Before
 	public void setTestRequestcontext() {
-		RequestContext context = new RequestContext();
-		RequestContext.testSetCurrentContext(context);
+		RequestContext.testSetCurrentContext(null);
+		RequestContext.getCurrentContext().unset();
 	}
 
 	protected String getRoute(String path) {
@@ -157,7 +157,7 @@ public abstract class ZuulProxyTestBase {
 	}
 
 	@Test
-	public void simpleHostRouteWithOriginalQString() {
+	public void simpleHostRouteWithOriginalQueryString() {
 		this.routes.addRoute("/self/**", "http://localhost:" + this.port);
 		this.endpoint.reset();