Dockerfile improvements again

[obilodeau]

Since we merged #190 we can apply further sizing improvements to our docker image

• Split GUI and not GUI into two images
• Staged build to drastically reduce image size (no more build-essentials package required)
• verify docker size improvements gains
• Apply staged build to GUI Dockerfile
• Add integration-gui integration-slim and latest-gui latest-slim tags to dockerhub automatic builds
• update docker-compose.yml and documentation
• add a Dockerfile.slim build in CI too

Size reduction

• The integration image is 63.24 MB now. That is down from 252.39 MB now in master or down from 570.26 MB for 0.4.1.
• The integration-gui image is 293.32 MB now. That is up from 252.39 MB now in master (which I suspect was broken for the GUI since I needed to add a package to make it work on my system) or down from 570.26 MB for 0.4.1.

Feedback required for Tag names

Because of @alxbl's upcoming work with video encoding and the needed dependencies, I'm not sure that -gui is the proper approach. Candidates:

• a) Current proposal: latest with minimal dependencies and latest-gui (with GUI but more later?)
• b) latest with minimal dependencies and latest-full (with everything)
• c) Turn it the other way around: latest with everything (GUI + video encoding, etc.) and latest-slim (I think python does it that way for official images)

[obilodeau]

New Dockerfile worked locally. Triggering an integration build to see how it goes over there and it's resulting size.

[obilodeau]

Verified image size in integration. Added at the top of the issue.

The integration image is 63.24 MB now. That is down from 252.39 MB now in master or down from 570.26 MB for 0.4.1.

Also added a question about tag names alternatives

[obilodeau]

Verified image size in integration-gui. Added at the top of the issue.

The integration-gui image is 293.32 MB now. That is up from 252.39 MB now in master (which I suspect was broken for the GUI since I needed to add a package to make it work on my system) or down from 570.26 MB for 0.4.1.

[obilodeau]

@alxbl when you have a minute, let's discuss the tag name approach that I added at the top of the PR. @Res260 feel free to chime in as well.

Once this will be figured out, I'll setup dockerhub and update the documentation accordingly.

[alxbl]

@alxbl when you have a minute, let's discuss the tag name approach that I added at the top of the PR.

I feel like a lot of images take the -slim tag approach, so I kinda like that one. By default you get everything (batteries included), and if you have specific needs, then you read the docs and find out that there's a slim build or a specific tag for your needs.

[obilodeau]

Changed the Dockerfile to use the slim approach. Configured an integration-slim build rule in DockerHub.

[obilodeau]

Image builds that happened during lunch:

• integration: 295.44 MB
• integration-slim: 65.37 MB

[obilodeau]

Merged this into integration to see if it builds. I'll finish and submit the PR tomorrow.

[Res260]

@obilodeau I don't know if you wanted to do it like that, but you can separate the two docker builds in two different jobs in the CI so they can run in parrallel instead of sequentially

[obilodeau]

@obilodeau I don't know if you wanted to do it like that, but you can separate the two docker builds in two different jobs in the CI so they can run in parrallel instead of sequentially

I decided to keep it into the same task consciously. My rationale was that this is one less ubuntu to start so we save a few seconds of CI time (not sure how much we use though). The two builds are closely related and some of the docker layers might be locally cached. I also believe that if one fails the other will probably too.

I haven't thought of the parallel argument. Good call. If I ever find myself waiting too much on this specific CI task I'll think about it.