Event Log

The event log is Chronicle's primary event sequence and is documented in the shared Chronicle docs.

• Events and event logs
• Appending events
• Appending many events
• Optimistic concurrency
• Getting events
• Observing appends
• Event redaction
• Closing streams
• TypeScript client setup

TypeScript client notes

• eventLog.redact(sequenceNumber, reason) and eventLog.redactForEventSource(eventSourceId, reason, eventTypes?) permanently rewrite an event's (or an entire event source's) content — a destructive GDPR/compliance erasure, never a field-level mask.
• eventLog.getForEventSourceIdAndEventTypes(eventSourceId, eventTypes, ...) and eventLog.getFromSequenceNumber(sequenceNumber, eventSourceId?, eventTypes?) read appended events back, filtered by event source and/or event type.
• eventLog.getNextSequenceNumber() returns the sequence number the next append will receive (EventSequenceNumber.first when the sequence is empty).
• eventLog.completeStream(eventStreamType, eventStreamId) permanently closes a non-default stream; further appends to it are rejected with a StreamClosed constraint violation.
• eventLog.appendOperations is a hot, multicast AsyncIterable of every append this event log instance makes, together with its result.
• appendResult.waitForCompletion(timeoutMs?) waits for every observer affected by an append to catch up (or fail) before you read a read model back — see Failed Partitions.
• The appendMany(events: EventForEventSourceId[], options?) overload now applies a distinct options.concurrencyScopes entry per event source id in the batch, instead of one shared scope applied to every event source.