如何检测python和flask中正在使用的两个虚拟主机中的哪个

Question

I have a website developed in flask running on an apache2 server that responds on port 80 to two URLs

Url-1 http://www.example.com

Url-2 http://oer.example.com

I want to detect which of the two urls the user is coming in from and adjust what the server does and store the variable in a config variable

app.config['SITE'] = 'OER'

or

app.config['SITE'] =  'WWW'

Looking around on the internet I can find lots of examples using urllib2 the issue is that you need to pass it the url you want to slice and I cant find a way to pull that out as it may change between the two with each request.

I could fork the code and put up two different versions but that's as ugly as a box of frogs.

Thoughts welcome.

Answer 1

Use the Flask request object ( from flask import request ) and one of the following in your request handler :

hostname = request.environ.get('HTTP_HOST', '')

url = urlparse(request.url)
hostname = url.netloc

This will get eg oer.example.com or www.example.com . If there is a port number that will be included too. Keep in mind that this ultimately comes from the client request so "bad" requests might have it set wrong, although hopefully apache wouldn't route those to your app.