Function isPeerAlive

src/utils/udsClient.ts:139–200

(
  socketPath: string,
  timeoutMs = 3000,
  authToken?: string,
)

 * Returns true if the peer responds within the timeout.
 */
export async function isPeerAlive(
  socketPath: string,
  timeoutMs = 3000,
  authToken?: string,
): Promise<boolean> {
  const token = authToken ?? (await findAuthTokenForSocketPath(socketPath))
  if (!token) return false

  return new Promise<boolean>(resolve => {
    const conn = createConnection(socketPath, () => {
      const ping: UdsMessage = {
        type: 'ping',
        ts: new Date().toISOString(),
        meta: { authToken: token },
      }
      conn.write(jsonStringify(ping) + '\n')
    })

    let resolved = false

    const timer = setTimeout(() => {
      if (!resolved) {
        resolved = true
        conn.destroy()
        resolve(false)
      }
    }, timeoutMs)

    let buffer = ''
    conn.on('data', chunk => {
      if (
        Buffer.byteLength(buffer, 'utf8') + getChunkBytes(chunk) >
        MAX_UDS_FRAME_BYTES
      ) {
        if (!resolved) {
          resolved = true
          clearTimeout(timer)
          conn.destroy()
          resolve(false)
        }
        return
      }
      buffer += chunk.toString()
      if (buffer.includes('"pong"')) {
        if (!resolved) {
          resolved = true
          clearTimeout(timer)
          conn.end()
          resolve(true)
        }
      }
    })

    conn.on('error', () => {
      if (!resolved) {
        resolved = true
        clearTimeout(timer)
        resolve(false)