Quick question about building a custom chat interface using the raw WebSocket Guest API instead of the hosted widget. We are moving away from the iframe widget for security reasons and need to handle the WebSocket lifecycle directly in a .NET 8 Blazor WebAssembly client.
I am following the documentation for the Guest API. The docs state: “After establishing the WebSocket connection, the client must send an authentication message with the guest ID and token.”
Here is my current implementation:
var ws = new ClientWebSocket();
var uri = new Uri("wss://api.mypurecloud.com/api/v2/webmessaging/guest/websocket");
await ws.ConnectAsync(uri, CancellationToken.None);
var authPayload = new {
type = "auth",
guestId = "my-static-guest-id",
token = "my-valid-oauth-token"
};
var json = JsonSerializer.Serialize(authPayload);
var buffer = Encoding.UTF8.GetBytes(json);
await ws.SendAsync(buffer, WebSocketMessageType.Text, true, CancellationToken.None);
The connection opens successfully, but immediately after sending the auth payload, I receive a WebSocket close code 1000 (Normal Closure) followed by a disconnect. The server does not send any JSON error object before closing.
I verified the token works with the REST endpoint GET /api/v2/webmessaging/guest/messages. The token is valid. I also tried adding conversationId to the payload, but the result is the same.
Is there a specific handshake step I am missing? The docs do not mention a specific message type for the initial connection before auth. Should I be sending a ping or init message first? Or is the type field case-sensitive? I tried Auth and AUTH as well, but no luck.
Any C# developers who have successfully implemented this raw WebSocket flow? The SDK does not seem to expose the WebSocket client directly, only the REST methods.
I am following the documentation for the Guest API. The docs state: “After establishing the WebSocket connection, the client must send an authentication message with the guest ID and token.”
I usually solve this by ensuring the auth payload matches the exact schema the gateway expects. In React Native, I’ve seen similar drops when the JSON structure is slightly off or the connection isn’t fully established before sending. For C#, make sure you are sending the auth command immediately after the socket state changes to Open.
var authPayload = new {
command = "auth",
guestId = guestId,
token = accessToken,
version = "1.0"
};
var json = JsonSerializer.Serialize(authPayload);
await webSocket.SendStringAsync(json);
Also, check that your token has the guest:api:read scope. If the server rejects it, the socket closes without a clear error often. I deal with this in Brazil where network latency sometimes causes timeout issues, so adding a small delay before sending can help. Don’t forget to handle the ping/pong frames or the server will kill the connection after 30 seconds.
TL;DR: Check the WebSocket state before sending auth and ensure the payload schema is exact.
It depends, but generally… the issue is timing. You cannot fire the auth message until the socket ReadyState is Open. In Blazor WebAssembly, the connection handshake can lag slightly. If you send the JSON before the state confirms open, the server drops it immediately.
Also, verify your payload structure. The Guest API is strict. It requires type: "auth" and the token in the correct field. I debug this often by logging the raw send buffer.
Here is the C# pattern that works reliably:
var authPayload = new {
type = "auth",
guestId = guestId,
token = token
};
// Wait for Open state explicitly
while (socket.State != WebSocketState.Open) {
await Task.Delay(50);
}
await socket.SendAsync(
Encoding.UTF8.GetBytes(JsonSerializer.Serialize(authPayload)),
WebSocketMessageType.Text,
true,
CancellationToken.None
);
Check your retry policy on the client side too. If the first send fails silently, you are stuck.
Make sure you verify the WebSocket ReadyState is explicitly Open before injecting the authentication payload, as the suggestion above correctly identifies the timing mismatch as the root cause. In my Ruby on Rails middleware for webhook ingestion, I face similar race conditions where Sidekiq jobs attempt to process events before the HTTP stream is fully stabilized. The C# Blazor WebAssembly environment adds another layer of complexity because the JavaScript interop can mask the actual connection state. You should implement a small polling mechanism or event listener that waits for the OnOpen event to fire completely. If you send the JSON authentication message while the socket is still in the Connecting state, the Genesys Cloud gateway will reject it instantly, causing the immediate drop you are observing. This is not a bug in the API but a strict adherence to the WebSocket protocol handshake sequence.
The payload structure must also be perfectly aligned with the Guest API schema, which is notoriously strict about field names and casing. Here is the exact JSON structure you need to send once the connection is confirmed open:
{
"type": "auth",
"guestId": "your-guest-uuid-here",
"token": "your-jwt-token-here"
}
Ensure that guestId matches the ID returned from the /api/v2/interactions/guests endpoint and that the token is a valid JWT with the correct scopes. In my Rails setup, I use Faraday to pre-validate the token expiration before initiating any WebSocket-like long-polling connections, which prevents these silent failures. If the token is stale or the guest ID does not match an active session, the server will close the connection without sending an error message back through the socket, making debugging difficult. Double-check your token generation logic in the .NET backend to ensure it includes the necessary chat:guest:write scope.
This is caused by…
Cause: Sending the auth JSON before the WebSocket ReadyState confirms Open. Blazor interop adds latency.
Solution: Wait for the open event. In my Laravel Guzzle workflows, I cache tokens, but here you must wait.
// Wait for Open state
if (socket.State == WebSocketState.Open) {
await socket.SendAsync(authJson);
}