Reverse-proxying with path rewrite breaks everything

[Sierra410]

Using nginx configuration similar to the following

location /some_prefix/ {
	rewrite ^/some_prefix/(.*) /$1 break;

	proxy_pass http://localhost:8100;
}

and using http://myserver/some_prefix as Server Url in extension's settings prevents the thing from working.

The server prints out Prepared room [id: ... blah blah ... ] upon trying to create a new session and nothing else.

The extension claims that a new session has been created successfully and copies the invite link.

Thirty seconds later Connection error: Websocket connection timed out. error is displayed.

Without /some_prefix and rewrite operation everything works as expected.

[msujew]

Hey @Sierra410,

This looks to be very similar to #177, which has been fixed in #182. That change is included in version 0.3.6 (currently latest) of the vscode extension. Are you using that to connect to the server?

I've also used nginx to validate my changes. This was the server config that I've used:

location /test/ {
    # Remove /test/ prefix when forwarding
    rewrite ^/test/(.*) /$1 break;
            
    # Proxy settings
    proxy_pass http://localhost:8100;
    proxy_http_version 1.1;
            
    # WebSocket support <-- maybe this part is missing? We're using websockets after all
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection $connection_upgrade;
            
    # Standard proxy headers
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;
            
    # Timeouts for long-lived connections (WebSockets)
    proxy_connect_timeout 7d;
    proxy_send_timeout 7d;
    proxy_read_timeout 7d;
            
    # Buffering settings
    proxy_buffering off;
}

[Sierra410]

I'm using the latest version of the extension, as for the server I've tried both the latest commit and the v0.3.0 tag. No difference.

Nginx logs show correct URLs and 200 status codes

... "GET /oct/api/meta HTTP/1.1" 200 64 "-" "node-fetch"
... "POST /oct/api/login/validate HTTP/1.1" 200 14 "-" "node-fetch"
... "POST /oct/api/session/create HTTP/1.1" 200 295 "-" "node-fetch"
... "GET /oct/api/meta HTTP/1.1" 200 64 "-" "node-fetch"
... "GET /oct/socket.io/?EIO=4&transport=polling&t=db6swf3l HTTP/1.1" 200 118 "-" "node-XMLHttpRequest"
... "GET /oct/socket.io/?EIO=4&transport=polling&t=db728sq6&sid=G25nojXrU_lzO1vgAAAB HTTP/1.1" 200 38 "-" "node-XMLHttpRequest"
... "POST /oct/socket.io/?EIO=4&transport=polling&t=db7211pw&sid=G25nojXrU_lzO1vgAAAB HTTP/1.1" 200 2 "-" "node-XMLHttpRequest"
... "GET /oct/socket.io/?EIO=4&transport=websocket&sid=G25nojXrU_lzO1vgAAAB HTTP/1.1" 101 0 "-" "-"
... "GET /oct/socket.io/?EIO=4&transport=polling&t=db7ci4s4&sid=G25nojXrU_lzO1vgAAAB HTTP/1.1" 200 1 "-" "node-XMLHttpRequest"
... "POST /oct/socket.io/?EIO=4&transport=polling&t=db7d4qom&sid=G25nojXrU_lzO1vgAAAB HTTP/1.1" 200 2 "-" "node-XMLHttpRequest"

But if there's a prefix that's being stripped, things fail.

The only line printed by the server is Prepared room [id: ...] for user [provider: 'Unverified' ...], and then silence.
On the client-side things pretend to work with an invite link and all being copied, but in reality it's just a matter of 30 seconds before the "timed out" error is displayed.

I've even tried doing location / combined with rewrite ^/(.*) /$1 break; (yes, it's replacing a slash with a slash) as a way to see whether it's nginx's rewrite that's messing things up, but that works equally as well as when no rewriting is done at all.

[msujew]

Hm, that's weird. I've posted my nginx.conf file below. It is setup to rewrite everything going to localhost:9000/test to localhost:8100. Can you try that one? I just re-verified that this still works as expected:

nginx.conf

events {
    worker_connections 1024;
}

http {
    # Basic Settings
    include mime.types;
    default_type application/octet-stream;


    # Performance
    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_types text/plain text/css text/xml text/javascript 
               application/json application/javascript application/xml+rss 
               application/rss+xml font/truetype font/opentype 
               application/vnd.ms-fontobject image/svg+xml;

    # WebSocket and proxy settings
    map $http_upgrade $connection_upgrade {
        default upgrade;
        '' close;
    }

    # Server configuration
    server {
        listen 9000;
        server_name localhost;


        location /test/ {
            # Remove /test/ prefix when forwarding
            rewrite ^/test/(.*) /$1 break;
            
            # Proxy settings
            proxy_pass http://localhost:8100;
            proxy_http_version 1.1;
            
            # WebSocket support
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection $connection_upgrade;
            
            # Standard proxy headers
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Forwarded-Proto $scheme;
            
            # Timeouts for long-lived connections (WebSockets)
            proxy_connect_timeout 7d;
            proxy_send_timeout 7d;
            proxy_read_timeout 7d;
            
            # Buffering settings
            proxy_buffering off;
        }

        # Health check endpoint (optional)
        location /health {
            access_log off;
            return 200 "OK\n";
            add_header Content-Type text/plain;
        }
    }
}

[Sierra410]

I've tested on my machine (Arch) with everything running on localhost.
I've tested with nginx terminating real HTTPS running on a Debian VPS.
I've tested with my own config and with yours.
I've tested in Codium and extension build from open-vsx, as well as VSCode and Microsoft market place build.

The issues is perfectly replicated each time. Path rewriting just... breaks stuff.

I have no idea what other variables might be at play.

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