E2/lp 10190 fix compressed content error (#353)

* Uncompress error responses too

* test cases added

Author: hrishileanplum

AndroidSDKCore/src/main/java/com/leanplum/internal/Util.java

@@ -668,16 +668,17 @@ public static void saveResponse(URLConnection op, OutputStream outputStream) thr
 
   private static String getResponse(HttpURLConnection op) throws IOException {
     InputStream inputStream;
+    String contentHeader = op.getHeaderField("content-encoding");
+    boolean isCompressed = contentHeader != null && contentHeader.trim().equalsIgnoreCase(Constants.LEANPLUM_SUPPORTED_ENCODING);
     if (op.getResponseCode() < 400) {
-      String contentHeader = op.getHeaderField("content-encoding");
-      if (contentHeader != null && contentHeader.trim().equalsIgnoreCase(Constants.LEANPLUM_SUPPORTED_ENCODING)) {
-        inputStream = new GZIPInputStream(op.getInputStream());
-      } else {
-        inputStream = op.getInputStream();
-      }
+      inputStream = op.getInputStream();
     } else {
       inputStream = op.getErrorStream();
     }
+
+    // If we have a gzipped response, de-compress it first
+    if (isCompressed) inputStream = new GZIPInputStream(inputStream);
+
     BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));
     StringBuilder builder = new StringBuilder();
     for (String line; (line = reader.readLine()) != null; ) {

AndroidSDKTests/src/test/java/com/leanplum/internal/UtilTest.java

@@ -68,4 +68,17 @@ public void getGzipEncodedResponseWithContentEndingTest() throws Exception {
     assertNotNull(Util.getJsonResponse(mockHttpUrlConnection));
   }
 
+
+  /**
+   * Test for {@link Util#getJsonResponse(HttpURLConnection op)} that returns gzip unmarshalled error data.
+   */
+  @Test
+  public void getGzipEncodedErrorResponseWithContentEndingTest() throws Exception {
+    HttpURLConnection mockHttpUrlConnection = mock(HttpURLConnection.class);
+    when(mockHttpUrlConnection.getErrorStream()).thenReturn(ResponseHelper.class.getResourceAsStream("/responses/simple_start_response.json.gz"));
+    when(mockHttpUrlConnection.getResponseCode()).thenReturn(403);
+    when(mockHttpUrlConnection.getHeaderField("content-encoding")).thenReturn("gzip");
+    assertNotNull(Util.getJsonResponse(mockHttpUrlConnection));
+  }
+
 }