AsyncAPI channel · Azure Web PubSub · Azure Web PubSub

/upstream

CloudEvents 1.0 HTTP delivery channel from the Web PubSub service to the customer-configured upstream webhook. The service POSTs one HTTP request per client event, using CloudEvents *binary* content mode (CloudEvents attributes are conveyed in `ce-*` HTTP headers; the event payload is the HTTP body). All requests carry `WebHook-Request-Origin: .webpubsub.azure.com` and a signed `ce-signa

Open source AsyncAPI → All Azure Web PubSub channels Azure Web PubSub provider profile
Provider: Azure Web PubSub AsyncAPI: v2.6.0 Spec: Azure Web PubSub Operations: 1 Messages: 5

Channel address

/upstream

Operations

upstreamDeliver
Events delivered by Azure Web PubSub to the upstream webhook. `connect` and user events are *blocking* events whose response the service waits for; `connected` and `disconnected` are *unblocking* (asy

Messages

upstreamSystemConnect
Blocking CloudEvents request fired during WebSocket handshake. The upstream may approve the connection (HTTP 200 with optional `userId`/`groups`/`roles`/`subprotocol` body, or HTTP 204) or deny it (4x
Content-Type: application/json
upstreamSystemConnected
Asynchronous notification fired after a client has successfully completed the WebSocket handshake. Upstream is expected to return a 2xx; non-2xx responses are logged by the service but do not affect t
Content-Type: application/json
upstreamSystemDisconnected
Asynchronous notification fired after a client disconnects, if the `connect` event previously returned a 2xx. The body carries the disconnect `reason`.
Content-Type: application/json
upstreamUserMessage
Blocking CloudEvents request fired for every WebSocket frame a *simple* (no subprotocol) client sends. The HTTP body is the raw payload the client sent. The upstream's response body, if any, is sent b
Content-Type: application/octet-stream
upstreamUserCustomEvent
Blocking CloudEvents request fired when a PubSub subprotocol client sends a `type: event` frame. The CloudEvents `ce-type` is `azure.webpubsub.user.` and the body is the `data` field of th
Content-Type: application/json

About AsyncAPI

The AsyncAPI specification describes event-driven APIs the way OpenAPI describes request/response APIs. A channel is the named pipe — a webhook URL, a Kafka topic, a WebSocket route, an MQTT subject — that producers and consumers publish or subscribe to. Each channel carries one or more messages with structured payloads, and an operation declares whether a given party sends or receives on that channel.

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