Finalevent

Finalevent is a term used in computing to describe the last event emitted by a source in an event-driven sequence. It acts as a termination signal indicating that no further data or events will follow and that the consumer may perform final processing or cleanup.

In data streams, publish-subscribe systems, and reactive pipelines, a finalevent is typically produced by the data source once it exhausts its data or when a process completes. Consumers use it to close resources, flush final results, or transition to a terminal state. Depending on the design, finalevent may carry metadata such as a final count, timestamp, or a summary payload.

Naming and implementation vary. Some systems treat finalevent as a specific event type or as a sentinel value within a stream. Others model completion with a separate complete signal or with an end-of-stream marker. The exact semantics—such as whether a finalevent is allowed to stream further data, whether it is emitted exactly once, and how errors are represented—depend on the framework.

Practical considerations include ensuring deterministic handling of finalevents, avoiding multiple emissions, handling late arrivals, and providing a graceful shutdown path for downstream components. In some contexts, finalevent is synonymous with end-of-file (EOF) in file streams or the onComplete callback in reactive programming.

Legacy usage and variants: While not a formal standard, finalevent appears in various codebases as a descriptive name for the end of a sequence. It shares concepts with end-of-stream, sentinel values, and completion notifications.