User Feedback - WebSocket support

Hey @kranthikumarkvs !

We have enabled support for subprotocols in the latest release. With this, you should now be able to use the Sec-WebSocket-Protocol header to negotiate the subprotocol with the server.

We are also actively working on adding dedicated support for few of the common subprotocols and will provide updates on the GitHub thread #9997, once we have something.


Thanks, @appurva.murawat for the update.
But still I see the same issue -

Error: Server sent a subprotocol but none was requested

In case you haven’t, be sure to update Postman: Help > Check for Updates
I hadn’t done so and it worked as soon as I did.

I’m trying to make it work with SignalR and c#, I was following a tutorial to test this from MS:
And it connects successfully using wss endpoint:

However none of the messages pass trough, and when I open it from webBroswer client (same client from the tutorial), and debug the code, it only shows 1 client connected (the browser one) ;/

As well verified from .NET code, that connection is not invoked, as there is a method in hub that can be accessed public override Task OnConnectedAsync() which does not get called

Wrote separate .net client and connected to the application, works just fine. But Postman even after connecting (shows connected successfully) receives no messages

Thanks, it worked after the update!

Hello, first of all, great work. I was so stoked to see this added. I even tweeted about it:

Really stoked that @getpostman has finally brought native WebSocket Support. Tried it with our WebSocket Endpoint and the basic functionalities seems to be working fine.

— Aakarsh Singh (@aakarsh7) May 21, 2021

Have been using it extensively post that. I have a suggestion for one feature which I think can improve the user experience dramatically. So WebSocket Servers generally have an auto-disconnect when they sense inactivity. Generally, WebSocket libraries have configurable control frames which can be set - this means that these control frames count towards activity and keep the connection alive.

If this can be added to Postman, it will really enhance the WS Support. A keep-alive sort of a thing that sends the PING Control Frame as per-user configuration.

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It would be useful if there was an option to send “beautified” json as a minimized string.

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Is there a plan/possibility to add websocket requests as part of a collection flow? including tests and the ability to setEnvironment variable and continue to another request.

My use case:
I have a post request, after that I expect a websocket message from the server, and then I want to have another post/get request which its input is the content of the websocket message.
Sounds like a very common scenario.


I am very confused. The option to create a websocket request is not present on my screen. I am on Ubuntu but I don’t see any information on the learning page or the blog about the feature to imply I have any reason not to see it.

Doesn’t seem clear either way.

That seems like a old version, it also doesn’t have the option to create a Workspace from that menu. :thinking:

Which version is this?

Ah, yes I am now looking at the changelog I’ve noticed the version number is much higher. In my defence it says the following for version number which I did check:

You’re on v7.36.5 . Snap will automatically update Postman whenever a new version is released.

Looks like Snap didn’t do what Postman said it was going to do :smiley: . Genuinely thought it was a problem with this feature. Apologies for bringing up what was just a general issue.

Yes, please! I love it - but I sure would like to be able to save them to a new WS Collection.


+1. The function of saving WebSocket connections is very missing


When will it be possible to save WebSocket connection in collection?


It’s a common misconception that Socket.IO is a WebSocket implementation. It is not.


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See previous post regarding

how to send heartbeat packet,and write prescript or test script?

messages won’t display error message

but in chrome, it will

@vadimsdaleckis We do not have an ETA yet, but it’s being worked on!

@asheroto We’ve just announced support for

@oyblog We’re already tracking pre-request and test scripts as a feature request. I’m adding sending an heartbeat packet too.

@posrix Please provide more details on what you’re sending, and what you’re expecting to receive.


Does Postman’s implementation support connecting to custom namespaces/paths?