support launchpad.net webhooks

[iainlane]

Details

I've got a project hosted on Launchpad which I have docs for. I'd like for our docs to be updated on push, but Launchpad's webhooks aren't supported by readthedocs, so while I have put the URL I got from rtd into Launchpad, nothing happens on push.

The format is documented here: https://help.launchpad.net/API/Webhooks

[stsewd]

Hi, I don't think we would implement a webhook for launchpad, we support webhooks for our supported vcs providers (gitlab, github and bitbucket), and we also have a manual webhook for other services https://docs.readthedocs.io/en/stable/webhooks.html#using-the-generic-api-integration. Maybe you can hook that into your CI.

[iainlane]

I think Launchpad would have to be changed to support adding the token via POST to make a custom integration work.

A question - in theory, would you accept a contribution (PR) to add Launchpad support?

[stsewd]

A question - in theory, would you accept a contribution (PR) to add Launchpad support?

Personally I don't think so, but maybe others have more opinions here /cc @readthedocs/core

I think Launchpad would have to be changed to support adding the token via POST to make a custom integration work.

If you are using a CI platform, I think that would be the easiest place to call the webhook.

[ericholscher]

Yea, I'm -1 on launchpad support. People using smaller platforms should use the generic webhooks. We don't want to promise to maintain launchpad support going forward, since we don't have a critical mass of users.

If there's improvements to the generic webhooks, we are definitely open to PR's and ideas there.

[astrojuanlu]

I made a reference to this issue in #8364, since both Gitea and Launchpad (as well as others) seem to be using the same X-Hub-Signature header.

[cjwatson]

Supporting the generic webhook would require non-trivial work in Launchpad, because (like GitHub et al) we don't support sending a webhook delivery with a user-specified payload, only a payload with the structure as explained in https://help.launchpad.net/API/Webhooks. I guess we might need to do this work at some point, but it will take some thought. I'd rather have direct integration (whichever side ends up doing most of the work) rather than requiring a CI hook.

It's disappointing to hear that a PR for Launchpad support in readthedocs wouldn't be accepted. I started sketching out https://paste.ubuntu.com/p/NHWB9D4fxs/ for that a while back just to see how hard it would be, though of course it would have needed tests.

[cjwatson]

https://bugs.launchpad.net/launchpad/+bug/1926431

[astrojuanlu]

@cjwatson Could you please test adding a GitHub webhook with the Launchpad URL and see if it works? From the preliminary investigation I did in #8364, I understood that Launchpad uses the same X-Hub-Signature header as GitHub does. A Gitea user reported success despite a dismissable error message.

[cjwatson]

@astrojuanlu I know it won't work. The X-Hub-Signature HTTP header is only one part of the problem; if you look at readthedocs.api.v2.views.integrations.GitHubWebhookView, it requires a particular payload structure as well that does not at all match what Launchpad sends.

[cjwatson]

Though I've added such a webhook for testing anyway, and will report back.

[cjwatson]

I can confirm that we just get a 400 error with no resulting builds. See https://readthedocs.org/dashboard/launchpad/integrations/161686/exchange/1f9c9c78-f6df-414e-b025-9758b082144f/, for instance. Gitea probably gets away with using the GitHub integration because it has a ref field in its payload.