Event Streaming

ExternalMessageService.StreamSendRequestEvents is a server-streaming RPC that delivers real-time events for your send requests. It replaces webhooks: your server opens the connection, so there is no public endpoint to expose, and gRPC TLS provides authentication and integrity (no HMAC signatures to verify).

Event types

Event type	Meaning
`RECIPIENT_DELIVERED`	Message delivered to the recipient
`RECIPIENT_FAILED`	Delivery failed
`RECIPIENT_PENDING_CONSENT`	Awaiting the recipient's consent
`CONSENT_GRANTED`	The recipient allowed messages from your app
`CONSENT_DENIED`	The recipient declined
`REQUEST_COMPLETED`	All recipients in a send request were processed
`POLL_RESPONSE_RECEIVED`	A recipient answered a poll

Event payload

Each SendRequestEvent contains:

Field	Type	Description
`event_id`	string	ULID — unique event id; use it as your cursor
`send_request_id`	string	The send request this event belongs to
`event_type`	enum	One of the types above
`recipient`	optional	Present for per-recipient events (`ppnum`, `error_code`, …)
`summary`	optional	Present for `REQUEST_COMPLETED` (`delivered`, `failed`, …)
`occurred_at`	string	Event timestamp (RFC 3339)

Reconnection

Pass after_event_id to resume from where you left off. Event IDs are ULIDs (chronologically sortable), and events missed during a disconnect are replayed on reconnect. Filter to a single send request with send_request_id, or omit it to receive all events for your app.

let mut cursor = load_saved_cursor().await;  // persisted last_event_id
loop {
    let mut client = connect_client(&token).await;
    if let Err(e) = stream_events(&mut client, cursor.clone()).await {
        eprintln!("stream error: {e}; reconnecting…");
        // back off before retrying
    }
    cursor = load_saved_cursor().await;       // updated as events arrive
}

Persist last_event_id durably — it's how the stream resumes without gaps. See Security.

First-time recipients must consent before they receive messages. Handle the RECIPIENT_PENDING_CONSENT / CONSENT_GRANTED / CONSENT_DENIED events — the bulk-messaging guide walks through the consent flow.