Function readSSELines

apps/sim/lib/core/utils/sse.ts:130–164

(source: SSESource, options: ReadSSELinesOptions)

 * @param options - The `onData` callback plus an optional `signal`.
 */
export async function readSSELines(source: SSESource, options: ReadSSELinesOptions): Promise<void> {
  const { onData, signal } = options
  const { reader, ownsLock } = toReader(source)
  const decoder = new TextDecoder()
  let buffer = ''

  try {
    while (true) {
      if (signal?.aborted) break

      const { done, value } = await reader.read()

      buffer += done ? decoder.decode() : decoder.decode(value, { stream: true })
      const lines = buffer.split('\n')
      buffer = done ? '' : (lines.pop() ?? '')

      for (const rawLine of lines) {
        if (signal?.aborted) return

        const line = stripCarriageReturn(rawLine)
        if (!line.startsWith('data:')) continue

        let data = line.slice(5)
        if (data.startsWith(' ')) data = data.slice(1)
        if (data === DONE_SENTINEL) continue

        if ((await onData(data)) === true) return
      }

      if (done) break
    }
  } finally {
    if (ownsLock) reader.releaseLock()
  }
}

/**
 * The JSON convenience layer over {@link readSSELines}: invokes `onEvent` once