# filename myapp.py
from flask import Flask, url_for

app = Flask(__name__)

@app.route('/')
def index():
 return 'hello flask'

@app.route('/test')
def test():
 return url_for('index', _external=True)

if __name__ == '__main__':
 app.run(debug=True)

(env) F:\tmp>python myapp.py
 * Running on http://127.0.0.1:5000/
 * Restarting with reloader

>>> from myapp import app
>>> with app.app_context():
... print url_for('index', _external=True)
...

Traceback (most recent call last):
 File "<stdin>", line 2, in <module>
 File "F:\tmp\env\lib\site-packages\flask\helpers.py", line 287, in url_for
 raise RuntimeError('Application was not able to create a URL '
RuntimeError: Application was not able to create a URL adapter for request indep
endent URL generation. You might be able to fix this by setting the SERVER_NAME
config variable.

>>> app.config['SERVER_NAME'] = 'example.com'
>>> with app.app_context():
... print url_for('index', _external=True)
...

http://example.com/

   -------->http://book.muxistudio.com
   ||
http://muxistudio.com-------->http://blog.muxistudio.com
   ||
   -------->http://share.muxistudio.com

127.0.0.1 flask.dev  localhost # 域名
127.0.0.1 test.flask.dev localhost # 子域名
127.0.0.1 othertest.flask.dev localhost # 子域名

#...
app = Flask(__name__)
app.config['SERVER_NAME'] = 'flask.dev:5000'
#...

#...
# Blueprint declaration
bp = Blueprint('subdomain', __name__, subdomain="<user>")

#...

# Register the blueprint into the application
app.register_blueprint(bp)
#...

flask.dev:5000 ----> muxistudio.com

 server {
 listen 80;
 listen 443 ssl;

 ssl_certificate /usr/local/nginx/ssl/nginx.crt;
 ssl_certificate_key /usr/local/nginx/ssl/nginx.key;

 server_name ~^www\.(?<user>.+\.)?markdownblog\.com$;
 return 301 "$scheme://${user}markdownblog.com$request_uri";
 }

 server {
 listen 80;
 listen 443 ssl;

 ssl_certificate /usr/local/nginx/ssl/nginx.crt;
 ssl_certificate_key /usr/local/nginx/ssl/nginx.key;

 server_name ~^.+\.markdownblog\.com$ markdownblog.com;

 location / {
  proxy_set_header Host $http_host;
  proxy_set_header X-Real-IP $remote_addr;
  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
  proxy_pass http://127.0.0.1:8085;
 }
}