Internal Server Error when using nginx proxy manager

[jfgarciamex]

Hi, I'm trying to use ngxinx proxy manager with slinger, but when I try to use I keep getting and Internal Server Error. For example, if I configure sling.test.net to forward it to the slinger server, I get the following in the slinger log:

02/20/2024, 20:26:52.249   RemoteControl connection from ('172.23.0.2', 44552)
Remote Control Connected
GET remote/
[2024-02-20 20:26:52,251] ERROR in app: Exception on /remote/ [GET]
Traceback (most recent call last):
  File "/home/slingbox/.env/lib/python3.11/site-packages/flask/app.py", line 1463, in wsgi_app
    response = self.full_dispatch_request()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/slingbox/.env/lib/python3.11/site-packages/flask/app.py", line 872, in full_dispatch_request
    rv = self.handle_user_exception(e)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/slingbox/.env/lib/python3.11/site-packages/flask/app.py", line 870, in full_dispatch_request
    rv = self.dispatch_request()
         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/slingbox/.env/lib/python3.11/site-packages/flask/app.py", line 855, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)  # type: ignore[no-any-return]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/slingbox/slingbox_server.py", line 1578, in index
    streamer, client, remote = get_streamer( request, text )
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/slingbox/slingbox_server.py", line 1520, in get_streamer
    port = request.headers.get('Host').split(':')[1]
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^
IndexError: list index out of range

I think the request from nginx proxy manager is not being managed correctly by slinger, as 172.23.0.2 is not the ip address of my client. Any suggestion to fix this. Thanks!

[GerryDazoo]

NGINX is not populating the "Host" information in the response. This is an NGINX problem not my code.

[jfgarciamex]

@GerryDazoo one more question, could be that instead of the host what is missing is the port? I'm asking as I found some issues reported already on the nginx proxy manager config, that may be missing the port in the forward url. Thanks!

[jfgarciamex]

@GerryDazoo,well, after investigating a bit, I found that adding the following directive to the custom location section solves the issue (so the problem is that the response does not include the port):

proxy_set_header Host $http_host:$proxy_port;

Thanks for your help!