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We have an angular front end that is connecting to a SignalR hub and are attempting to get it running as an Azure static web, but the connections are failing.
This is the error message.
main.js:1
[2022-06-09T14:27:28.831Z] Error: Failed to start the connection: Error: WebSocket failed to connect. The connection could not be found on the server, either the endpoint may not be a SignalR endpoint, the connection ID is not present on the server, or there is a proxy blocking WebSockets. If you have multiple servers check that sticky sessions are enabled.
This works when we host the site on an Azure App Service.
Can you please provide more details on how you have this set up? SignalR requires a server, where is that server hosted?
The SignalR is hosted on Azure using an App Service. We are using .net 6.
When I host the Angular site on one app service and the SignalR on another it is working without any issues, but if I attempt to use a static web app for the Angular front end it isn't able to connect to the SignalR hubs.
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As the signalr connection is from the browser, it does not matter how the html is hosted. It’s probably configuration. Does the static site have the correct url of the signalr server? Does the signalr server support CORS to the static site?
Turns out it was just a timing issue. It appears that it takes a while for Azure to process updates to CORS rules in an app service.
When I attempted to connect on Monday, everything was working so I'm guessing that it takes 24 hours or so to process the updates to CORS rules on an App Service within Azure.
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Thanks for the follow-up and sharing an update. Glad to know that it is working fine now.
Typically, it doesn't take a long time to reflect. To help get to the root of the issue, we can help investigate the issue further. For deeper insights, we will need subscription and resources details (for this - I'll follow-up with you privately), kindly let us know.
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