Building/testing for ARM does not happen often - the only runtime environment is Raspberry PI, which supports ARM64 - and complicates support for a ton of features. Aside from that, CI runs are much longer for ARM Dokku images, often reaching 15-20 minutes or just timing out completely.
Rather than support an architecture that doesn't have much usage by maintainers and has a lot of maintenance burden, we're removing the platform.
This change converts existing CHECKS files into a healthchecks key that is understood by 'docker-container-healthchecker'. This tool supports a number of different types of container healthchecks - command, http, uptime - and can perform healthchecks against non-web processes.
The use of the old CHECKS file is now deprecated, and will be removed in the next minor version. Users can use the 'docker-container-healthchecker' to convert existing CHECKS files to the new format automatically.
Closes#2760
This makes deploys faster for any that are built from source as the image artifact isn't involved in those cases while also unifying how the file is handled.
Refs #2760
Exposing all config values will allow users to skip setting environment variables twice - once as a docker option and once as an env var. Docker will automatically pull the value from the environment if none is set for the --build-arg flag.
Users will still be required to specify each desired env var via --build-arg as otherwise docker builds will complain about unused build arguments.
Re-implements #5978 (lost in a rebase)
Closes#5903
This ensures users don't have issues with cached state in regards to files pulled from the repo/image.
Also add missing docs for deploy-source-set trigger.
Closes#5963
Recent Dokku changes invalidate a bunch of docs around where files need to be placed in order for Dokku to respect them. This doc change clarifies where files are extracted from in cases where source code is available, which should hopefully make users less confused about how the system works.
See https://railsnotes.xyz/blog/deploying-ruby-on-rails-with-dokku-redis-sidekiq-arm-docker-hetzner for the inspiration - I was reading through it and was like 'these docs are definitely incorrect...'.
Since there's no instruction for how to use the DOKKU_LETSENCRYPT_EMAIL env variable, I'm not sure why it's included here.
So, instead, I'm proposing to include the step for directly setting the global email for `dokku-letsencrypt`.
(It'll be nice to also get some explanation behind creating that env variable)
While we will still build for 18.04, we will now stop testing against it. Instead, we will test against 20.04, the next EOL release after 18.04.
Once Ubuntu 18.04 is EOL, any references to it will also be removed.
Note that 18.04 support was already deprecated in Dokku 0.28.0, so this change is just acknowledging that deprecation.
While the majority of buildpacks do not work on non-amd64 platforms, this will at least allow developers the option to choose when to override this setting.
