Postfix PR title with [backport]

[watson]

This makes it possible to search for all GitHub e-mail notifications that involves a backport PR.

This can be really useful if you want to filter these kind of notification e-mails in a special way.

[epixa]

I like this idea, but I recommend this be implemented as a "title template" feature that we can configure through the .backportrc.json files. This allows for individual projects to maintain their own naming conventions, just like they do for branches and labels.

[watson]

@epixa This would mean that my Gmail filter would have to be manually maintained for each project that changes the default (if the default is to set it to for instance [backport]). Also, it would not work for projects that choose to not add a post-fix to the title at all. But I'm sure we can probably agree on a common post-fix across Elastic? But then again, that kind of defeats the purpose of having it configurable per project... 🤔 In any case I'm ok with making this configurable if you feel there's a use-case for it 😃

[epixa]

@watson Ah yeah, I understand your concern there, and I'm glad you mentioned something since I was specifically thinking about the per-project config so that we could not have the prefix in kibana's projects. Kibana PR lists already include a backport label and are pretty cluttered as-is.

Out of curiosity, can you filter on the content instead? If so, the backport description already includes the phrase Backports the following commits to, which you could filter on.

Anyway, I don't have very strong opinions about this, but as more and more people and projects use this tool, changing the hardcoded rules around content is going to be harder and harder without disrupting folks.

[sorenlouv]

Also chiming in here. The issue you (@watson) are describing with getting too many "noisy" backport emails is definitely something I'd like to see a solution for.
Adding a prefix/suffix to the title is one solution, but the title is already fairly long and I'm hoping we can find something more "elegant". Unfortunately I don't currently have anything better.

The optimal solution would be a filter that worked on non-visible fields like X-Github-headers. There are ways to get gmail to filter on these fields - but it requires some scripting. It's not super great: It only works for gmail, and it could very well be disabled in the future.

[watson]

Filtering on on the body text actually solves the problem, so I'm just going to close this PR.

Here's a cheatsheet for the filters you can set up:

For a specific repo on GitHub:

list:"REPO.USER.github.com" "Backports the following commits to"

For all repos under a GitHub org/user:

list:"USER.github.com" "Backports the following commits to"

For all repos on GitHub:

list:"github.com" "Backports the following commits to"

[sorenlouv]

Cool! Glad you got it working, and thanks for cheatsheet.

[watson]

Doh! This obviously only work for the initial email notification. But all activity that happens post the first, will of course not have that word in the body. Only the subject stays the same.

Any suggestions on how to get around this without modifying the subject?

[sorenlouv]

I only watch a few repos so I don't get notified unless I'm directly involved in a PR - not to say it isn't a problem, just that I'm not experiencing it, so haven't thought much about this.

Did you try setting a filter on [6.x], [6.3], [6.2], [6.1], [6.0]?

[watson]

That would work, but needs to be kept up to date all the time as new versions are released, so I would rather have a more "permanent" solution of course 😄