Allow for healthchecks and `depends_on` functionality on docker services that are extended

[guzman-raphael]

Feature Request

Problem

Currently if you attempt use extends on Docker Compose services with a depends_on configuration, it will throw an error.

Requirements

• Allow healthchecks to facilitate bringing services up in correct order
• Allow the extension or inheritance of services with such checks

Justification

This provides a healthy system and easy to diagnose the offending service.

Alternative Considerations

• Docker Compose extends and depends_on in 2.4 version.
• Multiple Docker Compose files.
• Docker Compose 3.X with checks specific to the container so they can be brought up in any order

Related Errors

For example:

rguzman@ALPHA:/github/datajoint-labbook$ PY_VER=3.8 IMAGE=djbase DISTRO=alpine PHARUS_VERSION=$(cat pharus/pharus/version.py | tail -1 | awk -F\' '{print $2}') DJLABBOOK_VERSION=$(cat package.json | grep \"version\" | awk -F\" '{print $4}') HOST_UID=$(id -u) docker-compose -f docker-compose-dev.yaml up --build
ERROR: Cannot extend service 'pharus' in /github/datajoint-labbook/pharus/docker-compose-dev.yaml: services with 'depends_on' cannot be extended

Additional Research and Context

• services with 'depends_on' cannot be extended docker/compose#3220

[SPONGE-JL]

Is there anyone who track this issue?

[codytowstik]

It would be nice if it didn't throw an error, and just ignored the depends_on.

See this comment: docker/compose#3220 (comment)

[guzman-raphael]

Welcome @SPONGE-JL! Yes, our open-source team is tracking and we should be able to address this soon.

Thanks for the find @codytowstik! We have a new upcoming release of both Pharus and SciViz so we have a good opportunity to include a fix for this.

That said, if you have any suggestions, we welcome contributions and can certainly assist you in getting it patched.