Where should I implement flask custom commands (cli)

Question

Creating custom commands in flask needs access to the app, which is generally created in app.py like this:

Answer 1

just import it in your app factory

dir tree

my_app
     L app.py
     L commands.py

commands.py

@app.cli.command('resetdb')
def resetdb_command():
    """Here info that will be shown in flask --help"""
    pass

app.py

def create_app():
    app = Flask(__name__)
    app.config['SQLALCHEMY_DATABASE_URI'] = DB_URL
    app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
    db.init_app(app)

    with app.app_context():
        from . import routes
        from . import commands  # <----- here

        return app

$ export FLASK_APP=my_app/app.py
$ flask resetdb

but there have to be better way ;) of which I am unaware right now

Answer 2

I have this layout:

baseapp.py

from flask import Flask

app = Flask("CmdAttempt")

app.py

from .baseapp import app

def main():
    app.run(
        port=5522,
        load_dotenv=True,
        debug=True
    )

if __name__ == '__main__':
    main()

commands.py

import click

from .baseapp import app


@app.cli.command("create-super-user")
@click.argument("name")
def create_super_user(name):
    print("Now creating user", name)


if __name__ == '__main__':
    from .app import main
    main()

In the console where you run the commands first define the FLASK_APP to be commands.py, then run the commands that you define.

set FLASK_APP=commands.py
export FLASK_APP=commands.py
flask create-super-user me

You can either use a separate terminal for built-in commands or clear the FLASK_APP variable before issuing them. In Linux is even easier because you can do

FLASK_APP=commands.py flask create-super-user me

Answer 3

One way to achieve this would be using blueprints

I have tested it using Flask 1.1.1, so be sure to check the documentation of the correct version that you have.

Here is the general idea:

1. Create one or more Blueprints in a different file, let's say it's called commands.py
2. Then import the new blueprints and register them to your app

==> app.py <==

from flask import Flask
from commands import usersbp

app = Flask(__name__)
# you MUST register the blueprint
app.register_blueprint(usersbp)

==> commands.py <==

import click
from flask import Blueprint

usersbp = Blueprint('users', __name__)

@usersbp.cli.command('create')
@click.argument('name')
def create(name):
    """ Creates a user """
    print("Create user: {}".format(name))

Upon executing flask users you should get a response like the following:

flask users
Usage: flask users [OPTIONS] COMMAND [ARGS]...

Options:
  --help  Show this message and exit.

Commands:
  create  Creates a user