Issues with Port Forwarding in GitHub Codespaces for Flask Application

[stoplyy]

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Hello GitHub Community,

I am experiencing issues with port forwarding in GitHub Codespaces while trying to develop a Flask application. Despite following the standard procedures for setting up port forwarding, I am unable to access the Flask server from outside the Codespace environment.

Environment Details:

• Language/Framework: Python with Flask
• Port: Typically 5000 (or any other port specified)
• Codespace Configuration: Default settings

Steps Taken:

Created a Flask app and set it to listen on 0.0.0.0 with a specified port.
Used the Flask development server to run the application.
Attempted to forward the port through the Codespaces UI (Remote Explorer).
Issue Description:
Whenever I try to forward the port, I receive the following message: "Unable to forward 127.0.0.1:5000. The host may not be available, or the remote port may already be forwarded." I've tried multiple ports but to no avail.

from flask import Flask
app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)

Troubleshooting Done:

Ensured that the application is binding to 0.0.0.0 and not localhost or 127.0.0.1.
Tried forwarding different ports.
Restarted Codespace multiple times.
I am looking for any insights or suggestions that might help resolve this port forwarding issue. Has anyone else faced similar issues? Any advice or troubleshooting tips would be greatly appreciated.

Thank you in advance for your help!

This draft aims to clearly outline your issue, the steps you've already taken, and the exact configuration you are using, making it easier for other community members or GitHub staff to understand and provide precise assistance.

[stoplyy]