Flask app with several blueprints route files-CodePudding

I am trying to wrap my head around blueprints in Flask. I started a minimal app to try and see how the setup should be, but I am getting an error when I try to run the app.

I have a venv with Python 3.9 and the following path values: PYTHONUNBUFFERED=1;FLASK_ENV=development;FLASK_APP=app.py

Here's the code: app.py

from flask import Flask

import routes_home
import routes_test

app = Flask(__name__)
app.register_blueprint(routes_home.home)
app.register_blueprint(routes_test.test)

if __name__ == "__main__":
    app.run(port=5000)

routes_home.py:

from flask import Blueprint, render_template, abort
from jinja2 import TemplateNotFound

home = Blueprint('home', __name__)

@home.route('/')
def home():
    return "<h1>Home</h1>"

routes_test.py

from flask import Blueprint, render_template, abort
from jinja2 import TemplateNotFound

test = Blueprint('test', __name__)

@test.route('/test')
def test():
    return "<h1>Test</h1>"

And here's the abbreviated traceback:

  File "/Users/asseeger/CloudStation/appfros.ch/dev/so-samples/py-blueprints/app.py", line 7, in <module>
    app.register_blueprint(routes_home.home)
  File "/Users/asseeger/CloudStation/appfros.ch/dev/so-samples/py-blueprints/venv/lib/python3.9/site-packages/flask/scaffold.py", line 56, in wrapper_func
    return f(self, *args, **kwargs)
  File "/Users/asseeger/CloudStation/appfros.ch/dev/so-samples/py-blueprints/venv/lib/python3.9/site-packages/flask/app.py", line 1030, in register_blueprint
    blueprint.register(self, options)
AttributeError: 'function' object has no attribute 'register'

What am I doing wrong here?

CodePudding user response：

The code suffers from naming confusion in this bit:

home = Blueprint('home', __name__)

@home.route('/')
def home():
    return "<h1>Home</h1>"

Here, home start life as a Blueprint, then becomes a function. The last binding wins.

app.register_blueprint(routes_home.home)

then attempts to register a function instead of a Blueprint. This is what

'function' object has no attribute 'register'

at the end of the stack trace hints at.

One way forward is to rename the first use to

home_bp = Blueprint('home', __name__)

(and propagate that name). The other is to rename the function. Your call as to which is clearer to your eye.