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Use a Procfile to define the process that is invoked when a container starts.
The Procfile can override the default start process for any language
type. Procfile support is provided by the entrypoint buildpack.
Procfile name and location
The Procfile is always a plain text file without a file extension.
Google Cloud's buildpacks searches for a file named Procfile at the root folder
of the project. The Procfile must live in your project's root directory and
cannot be placed anywhere else.
Procfile format
A Procfile declares its process types on individual lines, each with the following format:
PROCESS_TYPE: COMMAND
Replace:
- PROCESS_TYPE with an alphanumeric name for your command, such
as
web,workerandcustom. - COMMAND indicates the command that every process type should execute on startup, such as
gunicorn -b :$PORT main:app.