WATCHED_EXTs input format needs upgrading

[matthewbloch]

Currently you specify which files to send by specifying space-separated extensions in the WATCHED_EXTS variable, e.g. for Golang we'd use WATCHED_EXTS="go mod".

The matching code, after splitting on spaces, is strings.HasSuffix(path, "."+ext), i.e. it will match man.go but not mango.

We have a problem that we want to match files that have no extension e.g. Dockerfile, so this syntax needs changing to support it.

I could simply remove the "." from the check, but that leaves it open to uploading files it shouldn't when there's a typo e.g. if you entered a single character that would catch a lot of files by accident. But we still want to be able to use the exercise environment for common files that have a single letter extension e.g. .c or .h for the C language.

I'm going to update it to work (temporarily) two ways:

• if there's no . found in WATCHER_EXTS, it keeps to the current 👆🏻 behaviour
• if there's a . found in WATCHER_EXTS, it does not add the . to any extensions, assumes you are specifying them

This should allow us to push changes to the various docker-compose.yml files that use it, and then I can kick away the old parsing in the next release. Will document this properly in both phases; it should only be a few weeks of transition.

[sdpryan]

Sensible plan, thanks Matthew

[davidmillican]

Sounds good. And sounds fully backwards compatible, so the transition phase shouldn't be too painful.

[sdpryan]

The docker sync is currently broken without this, and we have a teachback for a Docker coach coming up. We could work around it, but if this can be fixed before then that'd be good.

This doesn't have to be Matthew, it could also be a task that'd be good for Alex?

[davidmillican]

Ah - I only rediscovered this issue now, and solved it a slightly different way to your suggestion @matthewbloch.

I think your (intermediate) approach falls down in the case that we are only watching files like Dockerfile (unless you added another extension with the . to switch mode e.g. .just-to-have-a-period).

Mine is also not an ideal forever fix (because if we were watching ".js Dockerfile" if would match all of test.js, Dockerfile and js. #14

However, the fourth commit will also allow that migration to happen, so should be fine.

[davidmillican]

This PR: https://github.com/skiller-whale/curriculum/pull/4181 adds periods to all the file extensions which would come after a period in all exercise configs in the curriculum repo.

(but they still need to be updated in the public repos).

[davidmillican]

This ticket updates all of the public repos in use to use the latest learnersync with . extensions being watched: https://github.com/skiller-whale/curriculum/issues/4191#issue-2237189716

[davidmillican]

Code change: #19

Going to hold off merging this for a while - see the PR for comments.