Flask URL Building

In Flask, URL building is done using the url_for() function, which dynamically generates URLs for your application’s routes. This is useful because it ensures that URLs are constructed correctly, even if routes change. The url_for() function takes the name of a view function and any arguments required to build the URL.

from flask import Flask, redirect, url_for

app = Flask(__name__)

@app.route('/admin')
def admin():
   return 'Hello Admin'

@app.route('/guest/<guest>')
def guest(guest):
   return f'Welcome {guest}'

@app.route('/user/<name>')
def user(name):
   if name =='admin':
      return redirect(url_for('admin'))
   else:
      return redirect(url_for('guest',guest = name))
      
if __name__ == '__main__':
    app.run(debug=True)

Output:

• When a user visits http://127.0.0.1:5000/user/admin
• Redirects to /admin
• Output: "Hello Admin".

• When a user visits http://127.0.0.1:5000/user/vrsofttech
• Redirects to /guest/vrsofttech
• Output: "Welcome vrsofttech".