i'm trying to create a web server with Flask python library but there is something wrong because it keeps giving me the error when i run the file.
here is the code:
from flask import Flask, app
app = Flask(__name__)
#app_route("/")
def main():
return('welcome to my flask page')
if __name__ == "__main__":
app.run(debug=True, host="0.0.0.0", port="8090")
here is the error:
Traceback (most recent call last):
File "c:\Users\User\Desktop\Simone\Simone\Js Course\Python Web Server\web server.py", line 5, in <module>
#app_route("/")
NameError: name 'app_route' is not defined
Help me please!!!
The app you're importing from flask isn't what you expect (it's a module within Flask that contains flask code). You need to create an instance of Flask, and apply the route to that.
from flask import Flask
app = Flask(__file__) # add this
#app.route('/') # and use app.route instead of app_route
...
Related
Usecase: I have a python flask app that runs background_function() before serving any requests on routes.
When I execute the flask app, I receive the error - RuntimeError: Working outside of application context. I receive the error since I try to get the application context before any request is served.
What is the best pythonic way to execute the background_function() in this example?
from flask import Flask
from download import Download
app = Flask(__name__)
app.config.from_pyfile('config.py')
# run backgroung function
Download.background_function()
#app.route('/')
def index():
return 'Welcome!'
if __name__ == '__main__':
app.run()
The config file
FILE_LOCATION = os.environ['FILE_LOCATION'] # "file/path/on/server"
# Many other variables are present in this file
The download file
from flask import current_app as app
class Download:
#staticmethod
def background_function():
file_path = app.config["FILE_LOCATION"]
# code to download file from server to local
return
Try this:
from flask import Flask
from download import Download
app = Flask(__name__)
#app.route('/')
def index():
return 'Welcome!'
if __name__ == '__main__':
Download.background_function()
app.run()
the download file
from flask import current_app as app
class Download:
#staticmethod
def background_function():
print("testing")
given output:
testing
* Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
As you can see, the function runs first and prints testing and then runs the application.
from flask import Flask
app = flask(__name__)
#app.route("/")
def home():
return "Hello world"
if __name__ == "__main__":
app.run()
and in termianl send me this error
Traceback (most recent call last):
File "C:\Users\xd\Desktop\python-anashe\index.py", line 3, in <module>
app = flask(__name__)
NameError: name 'flask' is not defined
You're importing the name Flask from the module flask.
That means you'll need (note the capital F)
app = Flask(__name__)
instead of lower-case app = flask(__name__).
trying to host my flask app (run.py) on PythonAnywhere. Have my virtualenv setup and all of my modules imported via pip. The flask app is stored at this location:
/home/goldsilvermonitor/GSM/run.py
Set up my WSGI file and it keeps giving my the error:
TypeError: 'module' object is not callable
My flask file look like this: (run.py)
from flask import Flask, flash, redirect, render_template, request, session, abort, url_for
app = Flask(__name__)
# ./Home Script:
#app.route("/")
#app.route("/index")
def index():
return render_template('index.html')
# ./Disclaimer Page:
#app.route("/disclaimer")
def disclaimer():
return render_template('disclaimer.html')
# ./data.xml:
app.route("/dataxml")
def dataxml():
return render_template('data.xml')
# ./404 Page
#app.errorhandler(404)
def page_not_found(e):
# 404 status set explicitly
return render_template('404.html'), 404
# FLask Debug Script:s
if __name__ == "__main__":
app.run(host="0.0.0.0", port='5000', debug=True)
And my WSGI file looks like this:
# +++++++++++ FLASK +++++++++++
# Flask works like any other WSGI-compatible framework, we just need
# to import the application. Often Flask apps are called "app" so we
# may need to rename it during the import:
#
#
import sys
#
## The "/home/goldsilvermonitor" below specifies your home
## directory -- the rest should be the directory you uploaded your Flask
## code to underneath the home directory. So if you just ran
## "git clone git#github.com/myusername/myproject.git"
## ...or uploaded files to the directory "myproject", then you should
## specify "/home/goldsilvermonitor/myproject"
path = '/home/goldsilvermonitor/GSM'
if path not in sys.path:
sys.path.append(path)
#
import run as application # noqa
#
# NB -- many Flask guides suggest you use a file called run.py; that's
# not necessary on PythonAnywhere. And you should make sure your code
# does *not* invoke the flask development server with app.run(), as it
# will prevent your wsgi file from working.
I have no idea what is causing this error. Have tried reuploading the files, redoing the WSGI config. But to no avail. If someone could help me then that would be great! Also should I remove the debug=true from the flask file before I go live?
You're trying to import a module (the file run.py) and then use it as an application; the application is the app object in that file, so in the WSGI file you should replace this:
import run as application # noqa
...with this:
from run import app as application # noqa
I have the following app which when I run using
flask run
seems to execute without error but when I perform python app.py gives me the following error:
➣ $ python app.py
Traceback (most recent call last):
File "app.py", line 14, in <module>
app.secret_key = os.environ['SECRET_KEY']
File "/Users/pkaramol/Workspace/second_flask/venv/bin/../lib/python3.7/os.py", line 678, in __getitem__
raise KeyError(key) from None
KeyError: 'SECRET_KEY'
#!/usr/bin/env python
import os
from flask import Flask
from flask_jwt import JWT, jwt_required
from flask_restful import Api
from flask_sqlalchemy import SQLAlchemy
import settings
from resources.item import Item, ItemList
app = Flask(__name__)
api = Api(app)
app.config.from_pyfile('settings.py')
app.secret_key = os.environ['SECRET_KEY']
db = SQLAlchemy(app)
if __name__ == "__main__":
print("Starting flask app...")
print(os.end['SECRET_KEY'])
db.create_all()
api.add_resource(Item, '/item/<string:name>')
api.add_resource(ItemList, '/items')
What is the difference in the two ways of running the flask app and why in the second case the environment is not rendered appropriately?
I am using python-dotenv to inject env vars from .env file
btw in the first case where the app starts without errors, I do not see the print statement I use for debug.
and if in the case of flask run the code below if __name__ == '__main__' is not called, how will I initialise my db by calling db.create_all()?
Replace app.secret_key assignment with arbitrary string.
I have a python file which defines some endpoints using flask each doing some computation and return a JSON (POST method). I want to do unit testing on this in order to do this I want to be able to access the app I created in one python file in another file so I can test my endpoints.
I see a lot of this on the internet :
from source.api import app
from unittest import TestCase
class TestIntegrations(TestCase):
def setUp(self):
self.app = app.test_client()
def test_thing(self):
response = self.app.get('/')
assert <make your assertion here>
It doesn't explain how I can define and access my app in another file. This might be a stupid question but I really don't see how.
My app is defined as follows:
from flasgger import Swagger
from flask import Flask, jsonify, request
from flask_cors import CORS
import os
def init_deserializer_restful_api():
# Initiate the Flask app
app = Flask(__name__)
Swagger(app)
CORS(app)
# Handler for deserializer
#app.route("/deserialize", methods=['POST'])
def handle_deserialization_request():
pass
I have many other end points in this fashion. Should i just do:
import my_file_name
Thanks!!
Check out this question: What does if __name__ == "__main__": do?
As long as you have that in your python program, you can both treat it as a module and you can call it directly.