@java.lang.Override
  public void writeTo(com.google.protobuf.CodedOutputStream output) throws java.io.IOException {
    if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(appId_)) {
      com.google.protobuf.GeneratedMessageV3.writeString(output, 1, appId_);
    }
    if (((bitField0_ & 0x00000001) != 0)) {
      output.writeMessage(2, getHttpBody());
    }
    getUnknownFields().writeTo(output);
  }
<pre>
The http body contains the queue.yaml file which used to update queue lists
</pre>

<code>optional .google.api.HttpBody http_body = 2;</code>
java-tasks/proto-google-cloud-tasks-v2beta2/src/main/java/com/google/cloud/tasks/v2beta2/UploadQueueYamlRequest.java