Pull timeout error doesn't have a code for easy error handling.

[Sh33pman]

Environment details

• OS: Mac OSX
• Node.js version: v8.12.0
• npm version: v6.4.1
• @google-cloud/pubsub version: v0.22.0

Steps to reproduce

1. Using pull function on pubsub.v1.SubscriberClient to pull messages from the a subscription, the example code works for testing, here is a bit of code I used to print the message:

subscriptionClient.pull().catch((err) => {
  let error_json = {};

  Object.getOwnPropertyNames(err).forEach(function (key) {
    error_json[key] = err[key];
  });
  console.log(err);
  console.log(error_json);
});

2. Ensure there is no messages sent to the subscription.
3. Wait until it reaches the pull timeout, will take 10 minutes.

Printed error

Error: Retry total timeout exceeded before any response was received
    at repeat (/Users/sh33pman/workspace/staffshift-bumblebee/node_modules/google-gax/build/src/api_callable.js:190:26)
    at Timeout.setTimeout [as _onTimeout] (/Users/sh33pman/workspace/staffshift-bumblebee/node_modules/google-gax/build/src/api_callable.js:218:25)
    at ontimeout (timers.js:498:11)
    at tryOnTimeout (timers.js:323:5)
    at Timer.listOnTimeout (timers.js:290:5)

{
	stack: 'Error: Retry total timeout exceeded before any response was received\n    at repeat (/Users/sh33pman/workspace/staffshift-bumblebee/node_modules/google-gax/build/src/api_callable.js:190:26)\n    at Timeout.setTimeout [as _onTimeout] (/Users/sh33pman/workspace/staffshift-bumblebee/node_modules/google-gax/build/src/api_callable.js:218:25)\n    at ontimeout (timers.js:498:11)\n    at tryOnTimeout (timers.js:323:5)\n    at Timer.listOnTimeout (timers.js:290:5)',
	message: 'Retry total timeout exceeded before any response was received'
}

The issue I'm currently facing is I need to handle that error so because it a new pull call needs to be started to ensure we keep checking for messages.

[callmehiphop]

You could try increasing the timeout for the request

const minute = 60000;
subscriptionClient.pull(null, {timeout: minute * 20});

Otherwise you could use the returnImmediately option. It should be noted that setting this option will cause the backend to respond immediately even if there are no messages available, so you'll have to implement your own polling logic.

subscriptionClient.pull({returnImmediately: true});

[Sh33pman]

@callmehiphop Sure but the issue with setting the timeout to 20 minutes, during times that the system is not busy the you will still have the same failure, also I personally think having an error code on the error makes more sense so you can identify why the pull failed.

In version 0.9.0 when pull was still on const PubSub = require('@google-cloud/pubsub'); object it didn't actually return an error if it timed out but rather returned an object with no messages, so would it not make sense to do the same or add an error code to the error so you could handle the timeout error in the same manner.

[callmehiphop]

My mistake! I didn't realize that google-gax was not supplying an error code of any kind. A status code would indeed be helpful here. I'm going to open an issue on google-gax and hopefully we can get this whole thing sorted out soon.

[Sh33pman]

@callmehiphop Thanks 😄

[callmehiphop]

Closing per #423, should be fixed in the next release!