python 51 lines · 7 steps

Custom user CLI commands in Flask

Group Click commands under a Flask AppGroup to manage users from the command line.

Explained by highlit
Flask Intermediate cli click command-group database user-management
1import click
2from flask.cli import AppGroup
3 
4from . import db
5from .models import User
6 
7user_cli = AppGroup("user", help="Manage application users.")
8 
9 
10@user_cli.command("create")
11@click.argument("email")
12@click.option("--password", prompt=True, hide_input=True, confirmation_prompt=True)
13@click.option("--admin", is_flag=True, help="Grant administrator privileges.")
14def create_user(email, password, admin):
15 if User.query.filter_by(email=email).first():
16 raise click.ClickException(f"A user with {email!r} already exists.")
17 
18 user = User(email=email, is_admin=admin)
19 user.set_password(password)
20 db.session.add(user)
21 db.session.commit()
22 click.secho(f"Created user {email} (id={user.id}).", fg="green")
23 
24 
25@user_cli.command("promote")
26@click.argument("email")
27def promote_user(email):
28 user = User.query.filter_by(email=email).first()
29 if user is None:
30 raise click.ClickException(f"No user found for {email!r}.")
31 
32 user.is_admin = True
33 db.session.commit()
34 click.secho(f"{email} is now an administrator.", fg="yellow")
35 
36 
37@user_cli.command("delete")
38@click.argument("email")
39@click.confirmation_option(prompt="Permanently delete this user?")
40def delete_user(email):
41 user = User.query.filter_by(email=email).first()
42 if user is None:
43 raise click.ClickException(f"No user found for {email!r}.")
44 
45 db.session.delete(user)
46 db.session.commit()
47 click.secho(f"Deleted {email}.", fg="red")
48 
49 
50def register_cli(app):
51 app.cli.add_command(user_cli)
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1An AppGroup bundles related Click commands under one namespace that shares the Flask app context.
  2. 2Click decorators declare arguments, prompts, and confirmations declaratively instead of hand-parsing input.
  3. 3Raising ClickException gives clean, exit-code-aware error messages instead of raw tracebacks.

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