in lib/google/serverless/exec/tasks.rb [240:316]
def show_usage
puts <<~USAGE
rake serverless:exec
This Rake task executes a given command in the context of a serverless
application. For more information,
on this capability, see the Google::Serverless::Exec documentation at
http://www.rubydoc.info/gems/google-serverless-exec/Google/Serverless/Exec
The command to be run may either be provided as a rake argument, or as
command line arguments delimited by two dashes "--". (The dashes are
needed to separate your command from rake arguments and flags.)
For example, to run a production database migration, you can run either
of the following equivalent commands:
bundle exec rake "serverless:exec[bundle exec bin/rails db:migrate]"
bundle exec rake serverless:exec -- bundle exec bin/rails db:migrate
To display these usage instructions, provide two dashes but no command:
bundle exec rake serverless:exec --
You may customize the behavior of the serverless execution through a few
enviroment variable parameters. These are set via the normal mechanism at
the end of a rake command line but before the double dash. For example, to
set EXEC_APP_CONFIG:
bundle exec rake serverless:exec EXEC_APP_CONFIG=myservice.yaml -- \\
bundle exec bin/rails db:migrate
Be sure to set these parameters before the double dash. Any arguments
following the double dash are interpreted as part of the command itself.
The following environment variable parameters are supported:
EXEC_PROJECT
The ID of your Google Cloud project. If not specified, uses the current
project from gcloud.
EXEC_PRODUCT
The product used to deploy the app. Valid values are "app_engine" or
"cloud_run". If omitted, the task will try to guess based on whether
an App Engine config file (e.g. app.yaml) is present.
EXEC_REGION
The Google Cloud region to which the app is deployed. Required for
Cloud Run apps.
EXEC_STRATEGY
The execution strategy to use. Valid values are "deployment" (which is the
default for App Engine Standard apps) and "cloud_build" (which is the
default for App Engine Flexible and Cloud Run apps).
Normally you should leave the strategy set to the default. The main reason
to change it is if your app runs on the Flexible Environment and talks to
a database over a VPC (using a private IP address). The "cloud_build"
strategy used by default for Flexible apps cannot connect to a VPC, so you
should use "deployment" in this case. (But note that, otherwise, the
"deployment" strategy is significantly slower for apps on the Flexible
environment.)
EXEC_TIMEOUT
Amount of time to wait before serverless:exec terminates the command.
Expressed as a string formatted like: "2h15m10s". Default is "10m".
EXEC_SERVICE_NAME
Name of the service to be used. If your app uses Cloud Run, this is
required. If your app uses App Engine, normally the service name is
obtained from the config file, but you can override it using this
parameter.
EXEC_APP_CONFIG
Path to the App Engine config file, used when your app has multiple
services, or the config file is otherwise not called "./app.yaml". The
config file is used to determine the name of the App Engine service.
Unused for Cloud Run apps.
EXEC_APP_VERSION
The version of the App Engine service, used to identify which
application image to use to run your command. If not specified, uses
the most recently created version, regardless of whether that version
is actually serving traffic. Applies only to the "cloud_build" strategy
for App Engine apps; ignored for the "deployment" strategy or if your
app uses Cloud Run.
EXEC_BUILD_LOGS_DIR
GCS bucket name of the cloud build log when GAE_STRATEGY is "cloud_build".
(ex. "gs://BUCKET-NAME/FOLDER-NAME")
EXEC_WRAPPER_IMAGE
The fully-qualified name of the wrapper image to use. (This is a Docker
image that emulates the App Engine environment in Google Cloud Build for
the "cloud_build" strategy, and applies only to that strategy.) Normally,
you should not override this unless you are testing a new wrapper.
USAGE
end