Add support for failure policies

[mad-it]

Currently its not supported to set retry policies in a firebase function. To enable retries, you have to go to the Google cloud console and enable retries.

This manual step makes the deployment non-idempotent.

There is an open issue + pull request for firebase-functions repository which add support for this feature on that side.
Issue: firebase/firebase-functions#425
Pull request: firebase/firebase-functions#482

I am creating this issue in here as a way to track progress on the missing feature for firebase-tools.

[samtstern]

@mad-it thanks for filing this.

@merlinnot (based on firebase/firebase-functions#482 (comment)) or @joehan if you can lay out what needs doing in this repo I could contribute the missing CLI pieces.

[merlinnot]

Sure thing.

There's an API design for this feature approved by the API Council: firebase/firebase-functions#425 (comment) with small changes: firebase/firebase-functions#425 (comment).

In short, I implemented everything that is needed to deliver this feature in firebase-functions, it was approved by @laurenzlong, but put on hold pending feature parity in firebase-tools. The implementation exposes __trigger.failurePolicy, which is equal to { retry: {} } or is unset. This matches the API specification of Cloud Functions: https://cloud.google.com/functions/docs/reference/rpc/google.cloud.functions.v1#failurepolicy.

In the API design you can find an information that optionally a boolean value must be accepted by this property, but this is handled by firebase-functions already and transformed to a canonical representation { retry: {} }, so you don't need to worry about it.

The most complex part seems to be user prompts when changing these policies. You'd need to compare existing deployment with a new one. All of the possibilities, both in interactive and non-interactive shells, with and without --force flag are described in the original design linked above.

Let me know if anything is unclear and thank you soooo so much for picking it up!

[laurenzlong]

Thanks for the helpful summary @merlinnot ! @samtstern happy to review the PR for CLI.

[samtstern]

I am working on this now, running into some strange issues with the Cloud Functions REST API but hoping to get them resolved soon

[samtstern]

Syntax support for this feature is included in firebase-functions version 3.10.0 and the next version of firebase-tools will contain the necessary deployment pieces.