private void doRequestHandleWithKeepAlive(EmbeddedChannel channel, HttpMethod httpMethod, RestMethod restMethod)
      throws IOException {
    for (int i = 0; i < 5; i++) {
      sendRequestCheckResponse(channel, httpMethod, restMethod, true);
      assertTrue("Channel is closed", channel.isOpen());
    }
  }
Does a test to see that request handling with good input succeeds when channel is keep alive.
@param channel the {@link EmbeddedChannel} to use.
@param httpMethod the {@link HttpMethod} for the request.
@param restMethod the equivalent {@link RestMethod} for {@code httpMethod}. Used to check for correctness of
                  response.
@throws IOException
ambry-rest/src/test/java/com/github/ambry/rest/NettyMessageProcessorTest.java