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apppack.toml

Warning

Using apppack.toml for app configuration is not yet generally available. If you'd like to try it out, please contact us.

This file can be used to configure how your app is built, released, and the services it will run when deployed.

TOML Syntax

TOML is a human-readable configuration format. It's similar to JSON or YAML, but with a different syntax. You can find a full reference of the syntax at toml.io.

You must store this file in the root of your repository and name it apppack.toml. If it exists, configuration via app.json will be ignored.

[build]

system

The tooling used to build your app.

  • Type: string
  • Values: dockerfile or buildpack
  • Default: buildpack
  • Required: No

buildpacks

The buildpacks used to build your app. Only used if system is set to buildpack.

  • Type: array of string
  • Values: A list of buildpacks, e.g. ["heroku/nodejs", "heroku/python"]
  • Default: [] (use auto-detection)
  • Required: No

builder

The buildpack builder used to build your app. Only used if system is set to buildpack.

  • Type: string
  • Values: A buildpack builder, e.g. "heroku/builder-cnb:22". The aliases heroku-20 (for heroku/buildpacks:20) and heroku-22 (for heroku/builder-classic:22) are also supported.
  • Default: "heroku-20"
  • Required: No

dockerfile

The path to the Dockerfile used to build your app. Only used if system is set to dockerfile.

  • Type: string
  • Values: A path to a Dockerfile, e.g. "Dockerfile"
  • Default: "Dockerfile"
  • Required: No

[test]

command

The command used to run your tests.

  • Type: string
  • Values: A command, e.g. "npm test"
  • Default: ""
  • Required: No

env

Environment variables to be used when building and testing your app.

  • Type: array of string
  • Values: A list of environment variables, e.g. ["FOO=bar", "BAZ=qux"]
  • Default: []
  • Required: No

[deploy]

release_command

The command used to release your app. Only used if build.system is set to dockerfile. Buildpack apps will use the release key in their Procfile.

  • Type: string
  • Values: A command, e.g. "python manage.py migrate --noinput"
  • Default: ""
  • Required: No

[review_app]

This section is only applicable for review apps. See Review Apps for more information.

initialize_command

The command used to perform a one-time initialize a review app. This is the equivalent of postdeploy on Heroku.

  • Type: string
  • Values: A command, e.g. "python manage.py load_initial_data"
  • Default: ""
  • Required: No

pre_destroy_command

The command used to perform a one-time cleanup before destroying a review app. This is the equivalent of pr-predestroy on Heroku.

  • Type: string
  • Values: A command, e.g. "python manage.py teardown_review_app"
  • Default: ""
  • Required: No

[services.<name>]

Only applicable if build.system is set to dockerfile. For buildpacks, the Procfile is used instead. Each table defines a service your app will run.

  • Type: table
  • Values: Must have a command key
  • Default: {}
  • Required: [services.web] is required if build.system is set to dockerfile

command

The command used to run the service.

  • Type: string
  • Values: A command, e.g. "npm start"
  • Default: ""
  • Required: Yes