Invoking SignalR from Postman

Question

I've been trying to invoke a simple Hub method from my .NET 8 web application, using SignalR.

I know that Postman needs to insert that unicode character at the end of the message, but it gives me a handshake error.

For example, I have this wss call: {"protocol":"json","version":1}

In Postman, it says "connected to wss://localhost:...", I don't see the {} response, although Postman says it's connected.

Then I try to send another message:

{ "arguments": ["just a test"], "target": "HubMethod", "type": 1 }

and I get "An unexpected error occurred during connection handshake."

This example is pretty simple, the same as what we have in the ASP.NET documentation.

Does anybody know how to test it using Postman?

Answer 1

All JSON messages must be terminated by the ASCII character 0x1E (record separator).

Here is the sample message for you. You can copy it from my gist link.