The `ps:scale` command now accepts a `--format` flag that defaults to `stdout` and can be set to `json` to emit the current formation as a JSON array of process type and quantity objects, matching the JSON output the `:report` subcommands already provide. The flag only applies when displaying the current formation; it is ignored when process types are supplied for scaling. When no scale has been set for the app, the JSON output is an empty array.
Procfile commands need to be expanded with actual environment variables as procfile-util will otherwise empty them out. This doesn't happen for app.json scripts as they are never expanded until the docker container gets created.
Closes#8050
Rather than redeploy every formation, only deploy formations that have had their values changed from the defaults.
This still doesn't handle the case where we touch existing processes when scaling _up_, but should decrease the number of services touched otherwise during scaling.
Also note that there are no tests for this new behavior yet (tests incoming).
Refs #7396
This change also moves the referenced Procfile out to a host path once on deploy vs potentially several times, which should speed up deploys a small amount and simplify reasoning about the file.
Closes#5112
This changes restarts to drop the 'release' part that currently gets triggered, which also helps reduce the possibility that a new image layer will be added due to predeploy deploy triggers.
Note that the old method essentially halfway-rebuilt the app (which was what added the extra layer). This refactor removes that, which is a bc-break.
Additionally, scaling processes will result in deploying _only_ restarting the processes being scaled.
Closes#2184
Rather than attempting to always extract the Procfile, reference the one that was extracted by the last deploy. This fixes issues where 'docker container cp' may fail intermittently for lord knows what reason.
Closes#4083
