Serving slivka under a subpath

[warownia1]

url_for works incorrectly when slivka is served under a sub-path /slivka Path prefix can be set using SCRIPT_NAME environ variable passed to flask app in wsgi handler:

class PrefixMiddleware:
  def __init__(self, app, prefix=''):
    self.app = app
    self.prefix = prefix

  def __call__(self, environ, start_response):
    if environ['PATH_INFO'].startswith(self.prefix):
      environ['PATH_INFO'] = environ['PATH_INFO'][len(self.prefix):] or '/'
      environ['SCRIPT_NAME'] = self.prefix
      return self.app(environ, start_response)
    else:
      start_response('404', [('Content-Type', 'text/plain')])
      return ["No prefix".encode()]

app.wsgi_app = PrefixMiddleware(app.wsgi_app, "/slivka")

Similarly you can run gunicorn with -e SCRIPT_NAME=/slivka or uwsgi with --manage-script-name --mount /slivka=wsgi:app

See also: https://gist.github.com/Larivact/1ee3bad0e53b2e2c4e40