Is it possible to call a SignalR Hub from Postman

Question

I have an ASP .Net Core 2.2 Web API with a SignalR hub. Is it possible to call one of its methods (for example, SendMessageToAll) using Postman? The problem is that I only have the API - no frontend - and I need to test.

I tried putting the URl to my hub in Postman (api.mydomain.com/chatHub) but then I'm not really sure how to structure the body. I know SignalR uses WebSockets preferably, and I don't know if PostMan has WebSocket functionality. I believe SignalR can also do HTTP requests if WebSockets is not available, which is something Postman can do. But what body do I use? And do I use an HTTP GET or POST?

I saw a post where the person was using this body in Postman:

{
    "Target": "SendMessageToGroup",
    "Arguments": [
        "groupA",
        "hello from server"
    ]
}

So I tried the same, but when I click "Send" on postman, the SendMessageToGroup method of my hub doesn't get triggered.

Thanks

Yes, *possible to call one of its methods (for example, SendMessageToAll) using Postman* — Divyang Desai, Jun 06 '19 at 09:35
Haha, thanks Div. I phrased my question wrongly, sorry about that. I meant to ask how can I do it :) I'm going to edit my question now... — Fabricio Rodriguez, Jun 06 '19 at 09:38
@dergroncki unfortunately not. i ended up using a small little piece of Angular code to test with. It basically just connects to my SignalR hub and invokes one of the Send methods on the hub. It also displays any messages it receives. I don't really know Angular but my colleague does, so he did it for me :) — Fabricio Rodriguez, Jun 24 '19 at 12:52

Nicolae · Answer 1 · 2021-05-28T07:36:43.357

11

Now is possible with Postman version > 8.0 using WebSocket Request block. You can grab the information in their blog post https://blog.postman.com/postman-supports-websocket-apis/

edited May 28 '21 at 07:36

answered May 26 '21 at 15:05

Nicolae

131
1
5

1

Thank you for your answer. It'd be nice if you could some example code. – shaedrich May 27 '21 at 07:26
Thanks Nicolae, that's great news! – Fabricio Rodriguez May 28 '21 at 06:29
1

I edited my answer with the link to their blog post in order to not be redundant – Nicolae May 28 '21 at 07:38
CLARIFICATION: This blog post says it's support *8.5* and above: https://blog.postman.com/postman-supports-websocket-apis/ – Glenn Ferrie Jan 19 '22 at 04:42

Mohammad Reza Mrg · Accepted Answer · 2022-02-04T16:07:53.893

5

Check Postman > 8. If you just inject your hub inside a controller then you can use hub's method and call it's public method from http request inside post man. Or use another app : https://stackoverflow.com/a/59543405/4751073

edited Feb 04 '22 at 16:07

answered Jul 15 '20 at 03:01

Mohammad Reza Mrg