Question

I want to implement structure in Flask, which can handle multiple domains.
So when I type in browser “http://domain1.com/show/1“, it actually executes function with routing like

@app.route('<string:domain>/show/<int:id>')
def show(domain = '', id = ''):
    return 'Domain is ' + domain + ', ID is ' + str(id)

And it is very important, the URL in client’s browser should be still “http://domain1.com/show/1“. And as I know, when using redirect in Flask, it changes url. How should I organise such structure? Thanks!

Answer 1

The request object already has a url_root parameter. Or you can use the Host header:

print request.url_root  # prints "http://domain1.com/"
print request.headers['Host']  # prints "domain1.com"

If you need to redirect within the application, url_root is the attribute to look at, as it’ll include the full path for the WSGI application, even when rooted at a deeper path (e.g. starting at http://domain1.com/path/to/flaskapp).

It probably is better still to use request.url_for() to have Flask generate a URL for you; it’ll take url_root into account. See the URL Building documentation.