Flask returns 404 with manager

Question

I have a small rest application with the following structure

Basedir
  - manage.py
  - load_gen
    - __init__.py
    - app.py
    - models.py

code snippet from manage.py

from load_gen import app, db
from load_gen.models import User
from flask.ext.script import Manager

manager = Manager(app)

if __name__ == '__main__':
    manager.run()

code snippet from init.py

import os

from flask import Flask
from flask_sqlalchemy import SQLAlchemy

basedir = os.path.abspath(os.path.dirname(__file__))

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'test.db')
db = SQLAlchemy(app)

from load_gen import models
from load_gen import app

and finally app.py

from flask import Flask, jsonify, abort,make_response,url_for    
from models import User

app = Flask(__name__)

tasks = [
    {
        'id': 1,
        'title': u'Buy groceries',
        'description': u'Milk, Cheese, Pizza, Fruit, Tylenol', 
        'done': False
    }
]
def make_public_task(task):
    new_task = {}
    for field in task:
        if field == 'id':
            new_task['uri'] = url_for('get_task', task_id=task['id'], _external=True)
        else:
            new_task[field] = task[field]
    return new_task

@app.route('/todo/api/v1.0/tasks', methods=['GET'])
def get_tasks():
    return jsonify({'tasks': [make_public_task(task) for task in tasks]})

if __name__ == '__main__':
    app.run(debug=True)

When I try to run this with python manage.py runserver, my app route is not registered and I keep getting 404 Not Found. url used - localhost:5000/todo/api/v1.0/tasks.

I have spent last 3 hours trying to figure out but am stuck. what am i doing wrong?

I don't think `app` in `manage.py` is your app, but the module instead (due to the last couple of lines in `__init__.py`). That could be the issue, though I'm surprised you're not running into other issues. — John Szakmeister, Dec 17 '15 at 22:59
you have app = Flask("app") in init.py (__init__.py ?) and app = Flask(__name__) in app.py. it's strange also — Gerard Rozsavolgyi, Dec 17 '15 at 23:05
app in manage.py prints "". Its loaded from __init_.py. Can you tell me what else I need to use there? — Abgo80, Dec 17 '15 at 23:07
@Gerard Rozsavolgyi - I was testing it. I changed it Flask(__name__). Will edit the code. — Abgo80, Dec 17 '15 at 23:08
You have three things named `app`. First you create an `Application` instance in `__init__.py`. Then you import a module named `app`, shadowing the instance. Your third `app` is the instance inside `app.py`. The two instances are going to going to give you problems, especially when the first gets shadowed by a module. — dirn, Dec 17 '15 at 23:45
@dirn - I changed app.py to load_app.py. Still nothing. I tried this helper [link](http://flask.pocoo.org/snippets/117/) and got following results `static HEAD,OPTIONS,GET /static/[filename]`. I believe my manager is not somehow registering my flask app. — Abgo80, Dec 18 '15 at 01:37

score 1 · Answer 1 · answered Dec 18 '15 at 05:24

The app you run and the app with which you register your routes are not the same.

In manage.py you have

from load_gen import app

manager = Manager(app)

In app.py (now load_app.py) you have

app = Flask(__name__)

@app.route('/todo/api/v1.0/tasks', methods=['GET'])
def get_tasks():
    return jsonify({'tasks': [make_public_task(task) for task in tasks]})

You need to use the same app everywhere. Don't define app in load_app.py and you should be all set, just remove the import at the end of __init__.py and change load_app.py to have

from load_gen import app

That did it. Thank you so much! Spent way too long on this. – Abgo80 Dec 18 '15 at 05:42 — Abgo80, Dec 18 '15 at 05:42

score 0 · Answer 2 · answered Dec 18 '15 at 03:33

Your manage.py is setting up things in a strange way. I would put some of that code at the end of __init__.py. After you import your models and the views (in app.py), create your manager, at the bottom of init.py:

manager = Manager(app)

if __name__ == '__main__':
    manager.run()

And then in your manage.py, all you have to do is this:

from load_gen import manager
manager.run()

Because the manager object is created inside the application module, and therefore has the views and database created in the proper context.

Flask returns 404 with manager

2 Answers2