Method appendChunk

packages/recorder-core/src/recording-spool.ts:268–304

(chunk: Blob)

	}

	appendChunk(chunk: Blob) {
		if (this.disposed) {
			return Promise.reject(new Error("Recording spool has been disposed"));
		}

		if (this.writeError) {
			return Promise.reject(this.writeError);
		}

		this.pendingChunks.push(chunk);
		this.pendingChunkBytes += chunk.size;
		if (this.pendingChunkBytes > this.maxPendingChunkBytes) {
			this.writeError = new RecordingSpoolBackpressureError();
			return Promise.reject(this.writeError);
		}

		return this.enqueue(async () => {
			const index = this.nextChunkIndex;
			const updatedSession = {
				...this.session,
				totalBytes: this.session.totalBytes + chunk.size,
				chunkCount: this.session.chunkCount + 1,
				updatedAt: Date.now(),
			} satisfies RecordingSpoolSessionRecord;

			await this.backend.appendChunk(updatedSession, index, chunk);
			const persistedChunk = this.pendingChunks.shift();
			if (persistedChunk) {
				this.pendingChunkBytes = Math.max(
					0,
					this.pendingChunkBytes - persistedChunk.size,
				);
			}
			this.nextChunkIndex = index + 1;
			this.session = updatedSession;
		});
	}

	// Heartbeat for the liveness contract above: refreshes the session's
	// updatedAt without writing a chunk so paused recordings stay recognisably