Documentation / @etherfold/browser / StoredLogEvent

Type Alias: StoredLogEvent<Extra>

StoredLogEvent<Extra> = BaseLogEvent<Extra> & object

Defined in: packages/core/dist/types.d.ts:70

ONE entry of the STORED STREAM: the raw log the node reported plus the reorg flag the indexer derived, and NOTHING an ABI made of those bytes.

args / eventName are what SOME ABI made of a log and decodeError is what happened when one could not, so both are a CACHE: LogEventFetcher.reparse re-derives them on read against the source running now, unconditionally, because a stream cannot say per event which ABI decoded it (ADR-0034). What is stored is therefore the half that is true forever, and the three ?: never clauses are what make the type SAY so rather than merely omit it.

A raw-only event is deliberately NOT a LogEvent: that is the union of a decode that SUCCEEDED (ParsedLogEvent) and one that FAILED (LogEventWithParsingFailure), and an event carrying neither belongs to neither. It is equally not BaseLogEvent, which is the SUPERTYPE both of those extend and which therefore enforces nothing: a decoded LogEvent[] is assignable to a BaseLogEvent[] -- that is what a supertype is -- and excess-property checks fire only on fresh object literals, so a keeper declared over the supertype could receive, hold and persist decoded events in silence.

It governs WRITES, from here on. Segments written before it existed still hold args and eventName forever and no migration rewrites them; a READ tolerates that half and ignores it, because the re-decode drops and re-derives it anyway. So this describes what goes IN, not what is guaranteed to be on disk. That rule, and the price of it, is ADR-0060.

The one hole, stated rather than hidden: an event whose STATIC type has already been widened to BaseLogEvent still assigns here, because nothing is left for the ?: never clauses to catch. The guard is at the SEAM -- what a keeper declares it takes and hands back -- and not through a widening, so a value laundered through the supertype defeats it.

Not EmittedLog, and both survive with this relation. They speak different seams and only one of them refuses anything. EmittedLog (a few lines below) is the SERVER's emission-row shape (ADR-0006): deliberately free of an ABI type parameter, and PERMISSIVE -- a plain NumberifiedLog alias that does not PROMISE the decoded half but does not refuse it either, and that can express neither extra nor removedStreamID. This one is what a keepStream keeper persists, carries both of those, and REFUSES a decoded event. Neither substitutes for the other, and EmittedLog is not to be re-pointed at this.

Pinned by test/storedLogEvent.test.ts, whose refusals are @ts-expect-error comments pnpm typecheck evaluates.

Type Declaration

args?

optional args?: never

decodeError?

optional decodeError?: never

eventName?

optional eventName?: never

Type Parameters

Extra

Extra extends JSONObject | undefined = undefined