This functionality enables users to manage a global crontab for the Dokku user that contains all scheduled tasks across all apps. Alternative schedulers can implement cron tasks as desired.
Containers can be attached:
- after they are created, but before they are started
- after a successful deploy, but before the proxy reloads
This allows folks to have flexibility around when they would like a container to be made available to a network.
The IMAGE_TAG is not always available, while the IMAGE_SOURCE_TYPE is. Since the point of these triggers was to unify the argument passed and make it easier to interact with them, this version makes more sense.
Closes#3780
After a `dokku run` container is created and started, this plugin trigger will allow developers to run auxiliary commands in response to that container.
This feature is allows users to add extra label metadata to one-off containers. As this can interfere with Dokku internals if they shadow labels used by plugins, care should be taken to avoid the `com.dokku` or `org.label-schema` namespace.
Also proper name run containers so they don't get random names from docker...
This PR uses the new syntax for commands introduced in Docker 1.13, making it a bit easier to understand just what a particular command is trying to do.
This also pushes the long-form syntax for docker command flags, which are also easier to understand at a glance.
This reduces duplication and allows users to rely on global arguments to generate most labels needed.
The 'commit' command cannot have global arguments because the whitespace within the label change breaks string-based interpolation, and shell arrays cannot be exported.
This change allows operators to specify a DOCKER_BIN environment variable. This will specify a binary to run when executing docker, which is useful in cases where the 'docker' command being run must be modified in a way that would otherwise be invasive to Dokku, but minimalistic if done within a wrapper.
While I do not agree with _every_ style change, this will force Dokku to have consistent formatting across all shell scripts, which is arguably a Good Thing™.
The command used to reprocess everything is:
```shell
shfmt -l -bn -ci -i 2 -w .
```