domain_dispatch_middleware.py

class DomainDispatchMiddleware(object):
  def __init__(self, domain_apps, default_app):
    """Constructor.

    Args:
      domain_apps: A list of (regexp, application) tuples to dispatch to based on domain.
      default_app: An app to run if no domain matches.
    """
    self.domain_apps = domain_apps
    self.default_app = default_app

  def __call__(self, environ, start_response):
    for regexp, application in self.domain_apps:
      if regexp.match(environ['HTTP_HOST']):
        return application(environ, start_response)
    return self.default_app(environ, start_response)

# Example usage:
application = domain_dispatch_middleware([
    ('mydomain\.com', mydomain_app),
    ('.*\.mydomain\.com', subdomain_app)],
    default_app)

def main():
  run_wsgi_app(application)