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
Provider:Azure Web PubSubAsyncAPI: v2.6.0Spec: Azure Web PubSubOperations: 1Messages: 5
Channel address
/upstream
Operations
subscribe
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.