Docker-Wrap

A drop-in wrapper for docker-compose that runs pre/post up and pre/post build scripts.

I frequently have scripts I want to run before/after docker-compose build/up. This wrapper creates a standard way to run everything by just wrapping docker-compose and passing through all arguments. You use it wherever you normally use docker-compose. You could even symlink it as docker-compose in your /usr/local/bin.

The wrapper is smart enough to run your pre-build, even when build is triggered by an up command.

The pre-build script runs before Dockerfile is loaded, so you can generate your Dockerfile from your pre-build script.

If you're just pulling an image and not building a new image, the pre/post build script does not run.

Install

If you want to install system-wide but also have edits you make here reflected in that system-wide install:

python3 -m setup develop

Or just install it like you normally would:

python3 -m setup install

Eventually, this will work, but I haven't uploaded it to PyPi yet:

pip3 install docker-wrap

Use

For any service, add an associative array x-wrap with one or more keys whose values are associative arrays named build or use. Those associative arrays should contain pre or post keys whose values are paths to scripts to run. See the example below.

docker-wrap will run any pre script before it runs your command, then run any post script. A future feature will that be if a pre script prints a valid yaml structure, docker-wrap will use that script as the docker-compose.yml for running the command.

docker-wrap passes all arguments on to docker-compose.

Something like this would work:

docker-wrap up foo

Sample docker-compose.yml

version: "3.9"
services:
  foo:
    x-wrap:
        build:
          pre: pre-build.sh bar baz
    build: bar

The default directory for running pre-build.sh will be the foo directory. If you set context, it will be the context.

Features Roadmap

[X] Pre/post build scripts
[X] Allow pre script to replace Dockerfile
[ ] Allow pre script to replace docker-compose
[X] Pre/post up scripts
[ ] Use wrap instead of x-wrap
[ ] pip installable

Contributing

Activity is in the GitHub Repo and you can always pop in to chat.opentechstrategies.com as well.

Please run the python qa script on the code before submitting a PR. That script just runs black, isort, mypy, and tests (tho we have no tests yet).

License and Copyright

Copyright 2020 James Vasile, published under the terms of AGPLv3 or later.