feat: introduces MFE_DOCKER_IMAGE_DEV_PREFIX

[rediris]

Introduces a MFE_DOCKER_IMAGE_DEV_PREFIX setting to customize dev MFE image docker repos. See discussion below for the benefits.

[rediris]

@regisb thoughts?

[regisb]

I'm not sure I understand. What problem exactly is this PR solving? Please describe your use case precisely, and how this change improves your workflow.

[rediris]

Yes, this probably deserves a bit more explanation than what I provided above.

Scenario 1: when customizing existing MFEs
Using a custom docker repo for MFE development images is currently impossible because the overhangio images are hard-coded into the plugin. While it is possible to override the tutor local mode production MFE image by using MFE_DOCKER_IMAGE in config.yml, this does not apply to the individual MFE images when running tutor in dev mode. This creates a bit of a development bottleneck, as the dev is forced to manually build/rebuild the development images instead of expediently pulling them from the custom docker repo. Additionally, the current process seems to necessitate using --no-cache and/or --no-registry-cache flags to prevent automatically pulling the default overhangio images.

Scenario 2: when creating new MFEs
The hard-coded overhangio image references create a similar problem when creating new MFEs. Let's say I have a custom MFE called frontend-app-customizeme - the resulting docker image path will look like
docker.io/overhangio/openedx-customizeme-dev:17.0.1 (based on what I'm seeing here: https://github.com/overhangio/tutor-mfe/blob/master/tutormfe/plugin.py#L154-L155).

Let me know if any of that makes sense...

[regisb]

OK I understand. For once, the "right" fix for this is to introduce a new setting: MFE_DOCKER_IMAGE_DEV_PREFIX="{{ DOCKER_REGISTRY }}overhangio/openedx-". Can you please change your PR to follow this approach? Please remember to include a changelog entry: https://docs.tutor.overhang.io/tutor.html#contributing

[rediris]

OK I understand. For once, the "right" fix for this is to introduce a new setting: MFE_DOCKER_IMAGE_DEV_PREFIX="{{ DOCKER_REGISTRY }}overhangio/openedx-". Can you please change your PR to follow this approach? Please remember to include a changelog entry: https://docs.tutor.overhang.io/tutor.html#contributing

Will do, thank you very much!

[rediris]

@regisb all set, let me know what you think!

[rediris]

Oops, forgot the changelog...

[regisb]

lgtm. @arbrandes what do you think?

[hinakhadim]

I have tested it. LGTM!