Conex support for multiple images in the same repo

[jakepruitt]

Conex currently only builds one container per repo.

We have a repo, we'll call it tabby-cat, which defines multiple containers and uses docker-compose as well as custom bash scripts to build and push the multiple images to ECR. The multiple images are tagged with:

tabby-cat:<git-sha>-rails
tabby-cat:<git-sha>-cgimap
tabby-cat:<git-sha>-orcd

where each of those sub-images is defined in a different part of the services section of the docker-compose.yml file.

It would be great if we could rewrite conex to support multiple containers.

Plan for how to do this

The outputs of docker-compose build are multiple images with the format tabby-cat_rails, tabby-cat_cgimap, etc., where tabby-cat is the name of the folder and rails is the name of the section of the docker compose file. Using some string transformations, I think we could re-tag these images with the <repo>:<gitsha>-<subimage> format and push all of them to ECR.

cc/ @Yuffster @rclark

[rclark]

Would there be a convention about Dockerfile locations within a repository, or would conex parse a docker-compose file?

[jakepruitt]

I don't think any parsing or conventions would be necessary: the docker-compose file defines where each image's context/Dockerfile lives and outputs all of those images in the format <folder-name>-<image-name> when running docker-compose build.

[rclark]

Oh I see -- so you're imagining that conex will run docker-compose build.

Once they're built, how would it know what it needs to retag & upload? If the image is <folder-name>-<image-name>, does that folder-name refer to where the Dockerfile was that built that image, or to the name of the folder containing the docker-compose file? If the prefix is consistent, then docker images --filter can likely find the images to upload.

[Yuffster]

It's the folder that the docker-compose file is in, which is nice because it leaves the actual Dockerfile locations up to the developer.

Currently I'm doing something like...

docker images --format '{{.Repository}}' | grep tabularasa
tabularasa_nginx
tabularasa_osmosis
tabularasa_cgimap
tabularasa_postgis
tabularasa_rails

And if I rename the folder...

cd ../
mv tabula-rasa nottabularasa
docker images --format '{{.Repository}}' | grep tabularasa
nottabularasa_nginx
nottabularasa_osmosis
nottabularasa_cgimap
nottabularasa_postgis
nottabularasa_rails

[rmrice]

This is a great idea that would be beneficial for project scalability and supporting different environments. Any movement on this?

[jakepruitt]

@rmrice @Yuffster I don't think this will be on anyone's roadmap until the end of May. I think the outline above would hopefully be enough to get started if either of you wanted to give it a shot before then.