Add handling of null response content (firebase#167)

funkybookends · hiranya911 · commit 8e3ee433b180 · 2018-04-23T10:06:19.000-07:00
* Add handling of null response content

If an error response comes back with no content, the json factory throws a
NullPointerException when it attempts to read the response, which hides the
response code from the client.

* Change catch NPE for null check in response content.
diff --git a/src/main/java/com/google/firebase/messaging/FirebaseMessaging.java b/src/main/java/com/google/firebase/messaging/FirebaseMessaging.java
@@ -253,13 +253,14 @@ private String makeSendRequest(Message message,
 
   private void handleSendHttpError(HttpResponseException e) throws FirebaseMessagingException {
     MessagingServiceErrorResponse response = new MessagingServiceErrorResponse();
-    try {
-      JsonParser parser = jsonFactory.createJsonParser(e.getContent());
-      parser.parseAndClose(response);
-    } catch (IOException ignored) {
-      // ignored
+    if (e.getContent() != null) {
+      try {
+        JsonParser parser = jsonFactory.createJsonParser(e.getContent());
+        parser.parseAndClose(response);
+      } catch (IOException ignored) {
+        // ignored
+      }
     }
-
     String code = FCM_ERROR_CODES.get(response.getErrorCode());
     if (code == null) {
       code = UNKNOWN_ERROR;
diff --git a/src/test/java/com/google/firebase/messaging/FirebaseMessagingTest.java b/src/test/java/com/google/firebase/messaging/FirebaseMessagingTest.java
@@ -172,6 +172,29 @@ public void testSendError() throws Exception {
     }
   }
 
+  @Test
+  public void testSendErrorWithZeroContentResponse() throws Exception {
+    MockLowLevelHttpResponse response = new MockLowLevelHttpResponse();
+    FirebaseMessaging messaging = initMessaging(response);
+    for (int code : HTTP_ERRORS) {
+      response.setStatusCode(code).setZeroContent();
+      TestResponseInterceptor interceptor = new TestResponseInterceptor();
+      messaging.setInterceptor(interceptor);
+      try {
+        messaging.sendAsync(Message.builder().setTopic("test-topic").build()).get();
+        fail("No error thrown for HTTP error");
+      } catch (ExecutionException e) {
+        assertTrue(e.getCause() instanceof FirebaseMessagingException);
+        FirebaseMessagingException error = (FirebaseMessagingException) e.getCause();
+        assertEquals("unknown-error", error.getErrorCode());
+        assertEquals("Unexpected HTTP response with status: " + code + "; body: null",
+            error.getMessage());
+        assertTrue(error.getCause() instanceof HttpResponseException);
+      }
+      checkRequestHeader(interceptor);
+    }
+  }
+
   @Test
   public void testSendErrorWithDetails() throws Exception {
     MockLowLevelHttpResponse response = new MockLowLevelHttpResponse();
