WebSockets connection fails if UpstreamPathTemplate doesn't point to / and contains {everything}

[eddex]

Expected Behavior

• The UpstreamPathTemplate can be changed to any path that should be used for the websockets connection

Actual Behavior

• With UpstreamPathTemplate "/{everything}" the websockets connection works
• With any UpstreamPathTemplate that doesn't contain "{everything}" the websockets connection works too
• Any other UpstreamPathTemplate that contains "{everything}" doesn't work

Steps to Reproduce the Problem

1. Use the following config for the websockets:

  {
    "UpstreamPathTemplate": "/{everything}",
    "DownstreamPathTemplate": "/{everything}",
    "DownstreamScheme": "wss",
    "DownstreamHostAndPorts": [
      {
        "Host": "echo.websocket.org",
        "Port": 443
      }
    ]
  }

2. Use the html provided on https://www.websocket.org/echo.html to test the connection. Change the wsUri to point to the local ocelot instance. Example: wss://localhost:44338/.
3. With this configuration, everything works fine.
4. Change the UpstreamPathTemplate to "/ws-echo/{everything}":

  {
    "UpstreamPathTemplate": "/ws-echo/{everything}",
    "DownstreamPathTemplate": "/{everything}",
    "DownstreamScheme": "wss",
    "DownstreamHostAndPorts": [
      {
        "Host": "echo.websocket.org",
        "Port": 443
      }
    ]
  },

5. Change the wsUri in the HTML file to reflect the changes. Example: wss://localhost:44338/ws-echo/.
6. Now the connection doesn't work anymore. The connection atempt fails with error: "WebSocket connection to 'wss://localhost:44338/ws-echo/' failed."

Specifications

• Version: Ocelot 16.0.1
• Platform: Windows, .NET Core 3.1
• Subsystem: IIS Express

[eddex]

I did some further testing and found that this configuration also works:

    {
      "UpstreamPathTemplate": "/ws-echo/",
      "DownstreamPathTemplate": "/",
      "DownstreamScheme": "wss",
      "DownstreamHostAndPorts": [
        {
          "Host": "echo.websocket.org",
          "Port": 443
        }
      ]
    },

This doesn't work:

    {
      "UpstreamPathTemplate": "/ws-echo/{everything}",
      "DownstreamPathTemplate": "/",
      "DownstreamScheme": "wss",
      "DownstreamHostAndPorts": [
        {
          "Host": "echo.websocket.org",
          "Port": 443
        }
      ]
    },

And this doesn't work either:

    {
      "UpstreamPathTemplate": "/ws-echo/",
      "DownstreamPathTemplate": "/{everything}",
      "DownstreamScheme": "wss",
      "DownstreamHostAndPorts": [
        {
          "Host": "echo.websocket.org",
          "Port": 443
        }
      ]
    },

[raman-m]

Marco,
You are talented tester.
@AlyHKafoury will help you more.

[eddex]

When using the /{everything} wildcard it seems like the initial forwarding of the request still works, the websocket endpoint returns a 101 Switching Protocols response but the api-gateway somehow fails to forward this to the client and runs into a timeout.