I have pip-installed Flask and HTML5 on my Window-system. When I start the Hello World!-program with IDLE, I get a red message in the Python-Shell:
"* Running on xxxx://127.0.0.1:5000/". (xxxx = http)
And when I start it with app.run(debug=True) another red message appears:
"* Restarting with reloader".
My browser (Firefox) shows no reaction.
What can I do to get 'Hello World' in a new tab of Firefox?
The Code is:
from flask import Flask
app = Flask(__name__)
#app.route("/")
def hello():
return "Hello World!"
if __name__ == "__main__":
app.run(debug=True)
return and app.run are indended
You have to open a new tab with this url:
http://127.0.0.1:5000/
You need to actually open the page in your browser - it won't open itself. Open Firefox and navigate to
127.0.0.1:5000
(it's a URL)
When you run your code, it sits around waiting for a request from the user. When it gets a request, it'll return a response, and that's (sort of) what you see in your browser. Going to a URL is how you send that request - Flask will interpret anything sent to 127.0.0.1:5000 as a request, and try to match the URL to one of your #app.route decorators. For example, if you were to have a function decorated with #app.route("/hello"), then when you go to 127.0.0.1:5000/hello, Flask would run that function to determine the response.
Try out this code:
from flask import Flask
app = Flask(__name__)
#app.route("/")
def index():
return "<h1>Hello!</h1>"
if __name__ == "__main__":
from waitress import serve
serve(app, host="0.0.0.0", port=8080)
refrence Flask at first run: Do not use the development server in a production environment
from flask import Flask
app = Flask(__name__)
#app.route("/")
def hello():
return "Hello World!"
if __name__ == "__main__":
app.run(debug=True)
Try this, this works for me. Open your firefox browser and go to the address given in the output. ex: http://XXXX.X.X.X:5000/
Related
from flask import Flask, escape, request
app = Flask(__name__)
run_with_ngrok()
#app.route('/')
def hello():
name = request.args.get("name", "World")
return f'Hello, {escape(name)}!'
When I run the this from terminal with "flask run" it doesn't print an ngrok link.
Im i an virtual env and i have tried running it with python "file name" and it did not work.
if you are trying to expose your ip through ngrok, you can try tunneling with ngrok on terminal for the flask app's port
your app code should look like :
from flask import Flask, escape, request
app = Flask(__name__)
#app.route('/')
def hello():
name = request.args.get("name", "World")
return f'Hello, {escape(name)}!'
if __name__ == "__main__":
app.run(port=5000)
you can tunnel the flask app port with the following command:
ngrok http 5000
here the port 5000 denotes the flask app port.
I think you forgot to add this part to end of your file
if __name__ == "__main__":
app.run()
from flask_ngrok import run_with_ngrok
from flask import Flask, escape, request
app = Flask(__name__)
app.secret_key = '33d5f499c564155e5d2795f5b6f8c5f6'
run_with_ngrok(app)
#app.route('/')
def hello():
name = request.args.get("name", "World")
return f'Hello, {escape(name)}!'
if __name__ == "__main__":
app.run(debug=True)
We can grab token from ngrok.com website by signin
In terminal we need to run like
ngrok config add-authtoken <your_token>
ngrok http 5000
for flask it is 5000 and for other application it would be different
And we also need to run our application side by side
When I run this Flask application logs in console seem to be fine, but I cannot find my webpage by the default url.
Error: Not Found
The requested URL was not found on the server. If you entered the URL manually please check your spelling and try again. I entered this URL : http://127.0.0.1:5000/ with the trailing slash.
Any thoughts?
from flask import Flask
app = Flask(__name__)
#app.route('/')
def home():
return "Hello, World! <h1>Hello, World!<h1>"
if __name__ == '__main__':
app.run(debug = False)
The error webpage looks like this
As you can see in the screenshot, the webserver is running. Just go to your browser and type in the search bar:
localhost:5000
When I run this code it gives a "404 page not found" error
from flask import Flask, render_template
app = Flask(__name__)
#app.route('/Home')
def home():
return "Hello World!"
if __name__ == '__main__':
app.run(debug=True)
You should set the route to home as just "/"
#app.route('/')
def home():
...
or visit /Home in your browser
Try changing the last line to app.run(host='0.0.0.0') and then use localhost:5000 to access the API. Here is a great tutorial I've used on setting up Flask on Ubuntu: https://www.digitalocean.com/community/tutorials/how-to-serve-flask-applications-with-uswgi-and-nginx-on-ubuntu-18-04.
I'm running this very simple application.py file, in debug mode, on my Mac.
import os
from flask import Flask, render_template
from flask_socketio import SocketIO, emit
app = Flask(__name__)
app.config["SECRET_KEY"] = "secret"
socketio = SocketIO(app)
#app.route("/")
def index():
return "hello"
if __name__ == '__main__':
socketio.run(app, debug=True)
It shows up on 127.0.0.1:5000. When I change return "hello" to return "goodbye" and refresh the page, nothing happens. When I try to return render_template(goodbye.html) from my templates directory, nothing happens. I even changed the route from '/' to '/bbbb' and nothing changed. I see a bunch of GET requests in my terminal, each with a status code of 200.
I've never had this problem with Flask, that is until I tried to use sockets.io. Any thoughts on what is happening?
I made the following file yesterday.
# import flask
from flask import Flask
from flask import render_template
from flask import request
app = Flask(__name__)
# create url & function mapping for root or /
#app.route('/')
def index():
return "Hello from Flask"
# create another mapping name /hello
#app.route('/hello')
def hello():
myName = "kayak"
return "Hello again !!" + myName
# create mapping for /myprofile
#app.route('/myprofile')
def showmyprofile():
return render_template('myprofile.html')
# create mapping for /myprofile
#app.route('/addprofileform')
def addprofileform():
return render_template('myprofileform.html')
# create a mapping for /addprofile
#app.route('/addprofile')
def addprofile():
myname = request.args.get('myname')
state_of_residence = request.args.get('state_of_residence')
return render_template('myprofile.html', html_page_name=myname,
html_page_state_of_residence=state_of_residence)
if __name__== '__main__':
app.run()
Then I made the following file today.
from flask import Flask
app = Flask(__name__)
#app.route('/')
def index():
return 'This is the homepage'
if __name__ == "__main__":
app.run(debug=True)
I thought
app.run(debug=True)
would work to clear the old data, but I doesn't and http://127.0.0.1:5000/ page keeps showing "Hello from Flask".
How do I fix this?
Just clear the cache in your browser and try running it again.
Here's how to clear your cache in some browsers:
Firefix->https://support.mozilla.org/en-US/kb/how-clear-firefox-cache
Chrome->https://support.google.com/accounts/answer/32050?co=GENIE.Platform%3DDesktop&hl=en
You can export the FLASK_ENV environment variable and set it to development before running the server
export FLASK_ENV=development
flask run
This worked for me.
Running the program in incognito tab will not cause this error. No need to clear caches also. See https://support.google.com/chrome/answer/95464?co=GENIE.Platform%3DAndroid&hl=en