Fix zuul error when there are colons in request param name.

Previously, parameter names with colons (ie foo:bar), caused an IllegalArgumentException because 41c364002f introduced UriTemplate to properly encode.

fixes gh-1193

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

@@ -249,6 +249,12 @@ public class ProxyRequestHelper {
 			MultiValueMap<String, String> headers) {
 	}
 
+	/**
+	 * Get url encoded query string. Pay special attention to single parameters with no values
+	 * and parameter names with colon (:) from use of UriTemplate.
+	 * @param params Un-encoded request parameters
+	 * @return
+	 */
 	public String getQueryString(MultiValueMap<String, String> params) {
 		if (params.isEmpty()) {
 			return "";
@@ -260,10 +266,21 @@ public class ProxyRequestHelper {
 			for (String value : params.get(param)) {
 				query.append("&");
 				query.append(param);
-				if (!"".equals(value)) {
-					singles.put(param + i, value);
+				if (!"".equals(value)) { // don't add =, if original is ?wsdl, output is not ?wsdl=
+					String key = param;
+					// if form feed is already part of param name double
+					// since form feed is used as the colon replacement below
+					if (key.contains("\f")) {
+						key = (key.replaceAll("\f", "\f\f"));
+					}
+					// colon is special to UriTemplate
+					if (key.contains(":")) {
+						key = key.replaceAll(":", "\f");
+					}
+					key = key + i;
+					singles.put(key, value);
 					query.append("={");
-					query.append(param + i);
+					query.append(key);
 					query.append("}");
 				}
 				i++;

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

@@ -259,6 +259,28 @@ public class ProxyRequestHelperTests {
 		assertThat(queryString, is("?wsdl"));
 	}
 
+	@Test
+	public void getQueryStringEncoded() {
+		MultiValueMap<String, String> params = new LinkedMultiValueMap<>();
+		params.add("foo", "weird#chars");
+
+		String queryString = new ProxyRequestHelper().getQueryString(params);
+
+		assertThat(queryString, is("?foo=weird%23chars"));
+	}
+
+	@Test
+	public void getQueryParamNameWithColon() {
+		MultiValueMap<String, String> params = new LinkedMultiValueMap<>();
+		params.add("foo:bar", "baz");
+		params.add("foobar", "bam");
+		params.add("foo\fbar", "bat"); // form feed is the colon replacement char
+
+		String queryString = new ProxyRequestHelper().getQueryString(params);
+
+		assertThat(queryString, is("?foo:bar=baz&foobar=bam&foo%0Cbar=bat"));
+	}
+
 	@Test
 	public void buildZuulRequestURIWithUTF8() throws Exception {
 		String encodedURI = "/resource/esp%C3%A9cial-char";

spring-cloud-netflix-core/src/test/java/org/springframework/cloud/netflix/zuul/filters/route/restclient/RestClientRibbonCommandIntegrationTests.java

@@ -186,6 +186,17 @@ public class RestClientRibbonCommandIntegrationTests extends ZuulProxyTestBase {
 		assertEquals("/query?foo=weird#chars", result.getBody());
 	}
 
+	@Test
+	public void simpleHostRouteWithColonParamNames() {
+		this.routes.addRoute("/self/**", "http://localhost:" + this.port + "/");
+		this.endpoint.reset();
+		ResponseEntity<String> result = new TestRestTemplate().exchange(
+				"http://localhost:" + this.port + "/self/colonquery?foo:bar={foobar0}&foobar={foobar1}", HttpMethod.GET,
+				new HttpEntity<>((Void) null), String.class, "baz", "bam");
+		assertEquals(HttpStatus.OK, result.getStatusCode());
+		assertEquals("/colonquery?foo:bar=baz&foobar=bam", result.getBody());
+	}
+
 	@Test
 	public void simpleHostRouteWithContentType() {
 		this.routes.addRoute("/self/**", "http://localhost:" + this.port + "/");
@@ -295,10 +306,15 @@ public class RestClientRibbonCommandIntegrationTests extends ZuulProxyTestBase {
 		}
 
 		@RequestMapping("/query")
-		public String addQuery(HttpServletRequest request, @RequestParam String foo) {
+		public String query(HttpServletRequest request, @RequestParam String foo) {
 			return request.getRequestURI() + "?foo=" + foo;
 		}
 
+		@RequestMapping("/colonquery")
+		public String colonQuery(HttpServletRequest request, @RequestParam(name = "foo:bar") String foobar0, @RequestParam(name = "foobar") String foobar1) {
+			return request.getRequestURI() + "?foo:bar=" + foobar0 + "&foobar=" + foobar1;
+		}
+
 		@RequestMapping("/matrix/{name}/{another}")
 		public String matrix(@PathVariable("name") String name,
 				@MatrixVariable(value = "p", pathVar = "name") int p,