I am trying to enforce Blazor Interactive Server to use WebSocket only to be able to use it in a load balanced setting. Sticky Session cannot be used due to IT Policy.
When I try running it locally, it works. However, when testing it in one of our Testing environment (which has no load balancer), it returns a 400 error:
wss://<Page>/<Subdirectory>/<BlazorHomePage>/_blazor
400 Bad Request
In the Client Browser, it gives this error in the console:
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.
I can't test it in a load balance setting if it doesn't get past the first Testing environment. Does anyone have a solution for this error?
This is what I have in Program.cs to be able to setup the Transport:
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseAntifery();
app.MapRazorComponents<App>()
.AddInteractiveServerRenderMode();
app.MapBlazorHub(e =>
{
e.Transports = Microsoft.AspNetCore.Http.Connections.HttpTransportType.WebSockets;
}).WithOrder(-1);
app.Run();
I've added Blazor.start to configure for WebSocket transport in App.razor:
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<base href="@BaseUrl" />
<link rel="stylesheet" href="bootstrap/bootstrap.min.css" />
<link rel="stylesheet" href="app.css" />
<link rel="stylesheet" href="BaseBlazorApp.styles.css" />
<link rel="icon" type="image/png" href="favicon.png" />
<HeadOutlet @rendermode="InteractiveServer" />
</head>
<body>
<Routes @rendermode="InteractiveServer" />
<script src="_framework/blazor.web.js" autostart="false"></script>
<script>
Blazor.start({
circuit: {
configureSignalR: function (builder) {
builder.withUrl("_blazor", {
skipNegotiation: true,
transport: 1
});
}
}
})
</script>
</body>
Another thing to note is that I have the <base> set up differently from a standard Blazor project to be able to run the app in a subdirectory without issue, and has been working before.