URL-encode job ID when forwarding from UIController

Motivation:
Download of files from the web UI fails if the job ID contains certain characters (such as '+').
This is due to URL decoding performed on the "forward URL" string returned by UIController (before passing the URL to JobRestController).

Change:
URL-encode the ID contained in the forward string.
This results in the ID being decoded back by Spring MVC to it's original format, and passed intact to the downstream JobRestController.

genie-web/src/main/java/com/netflix/genie/web/controllers/UIController.java

@@ -17,6 +17,7 @@
  */
 package com.netflix.genie.web.controllers;
 
+import lombok.extern.slf4j.Slf4j;
 import org.springframework.security.core.Authentication;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.PathVariable;
@@ -28,6 +29,8 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.validation.constraints.NotNull;
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
 
 /**
  * Controller for forwarding UI requests.
@@ -36,6 +39,7 @@
  * @since 3.0.0
  */
 @Controller
+@Slf4j
 public class UIController {
 
     /**
@@ -71,9 +75,19 @@ public String getIndex(@NotNull final HttpServletResponse response, @Nullable fi
      * @param id The id of the job
      * @param request the servlet request to get path information from
      * @return The forward address to go to at the API endpoint
+     * @throws UnsupportedEncodingException if URL-encoding of the job id fails
      */
     @RequestMapping(value = "/file/{id}/**", method = RequestMethod.GET)
-    public String getFile(@PathVariable("id") final String id, final HttpServletRequest request) {
-        return "forward:/api/v3/jobs/" + id + "/" + ControllerUtils.getRemainingPath(request);
+    public String getFile(
+        @PathVariable("id") final String id,
+        final HttpServletRequest request
+    ) throws UnsupportedEncodingException {
+        // When forwarding, the downstream ApplicationContext will perform URL decoding.
+        // If the job ID contains special characters (such as '+'), they will be interpreted as url-encoded and
+        // decoded, resulting in an invalid job ID that cannot be found.
+        // To prevent this, always perform URL encoding on the ID before forwarding.
+        final String encodedId = URLEncoder.encode(id, "UTF-8");
+        final String path = "/api/v3/jobs/" + encodedId + "/" + ControllerUtils.getRemainingPath(request);
+        return "forward:" + path;
     }
 }

genie-web/src/test/java/com/netflix/genie/web/controllers/UIControllerUnitTests.java

@@ -31,6 +31,7 @@
 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
+import java.net.URLEncoder;
 import java.util.UUID;
 
 /**
@@ -75,9 +76,10 @@ public void canGetIndex() {
 
     /**
      * Make sure the getFile method returns the right forward command.
+     * @throws Exception if an error occurs
      */
     @Test
-    public void canGetFile() {
+    public void canGetFile() throws Exception {
         final String id = UUID.randomUUID().toString();
         final HttpServletRequest request = Mockito.mock(HttpServletRequest.class);
 
@@ -88,9 +90,12 @@ public void canGetFile() {
             .when(request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE))
             .thenReturn("/file/{id}/**");
 
+        final String encodedId = URLEncoder.encode(id, "UTF-8");
+        final String expectedPath = "/api/v3/jobs/" + encodedId + "/output/genie/log.out";
+
         Assert.assertThat(
             this.controller.getFile(id, request),
-            Matchers.is("forward:/api/v3/jobs/" + id + "/output/genie/log.out")
+            Matchers.is("forward:" + expectedPath)
         );
     }
 }