Function createChannel

test/browser/specs/inspect.test.ts:51–102

(url: string)

}, 60_000)

async function createChannel(url: string) {
  const ws = new WebSocket(url)

  let id = 1
  let listeners = []

  ws.onmessage = (message) => {
    const response = JSON.parse(message.data.toString())
    listeners.forEach(listener => listener(response))
  }

  async function receive(methodOrId?: string | { id: number }): Promise<Message> {
    const { promise, resolve, reject } = withResolvers()
    listeners.push(listener)
    ws.onerror = reject

    function listener(message) {
      const filter = typeof methodOrId === 'string' ? { method: methodOrId } : { id: methodOrId.id }

      const methodMatch = message.method && message.method === filter.method
      const idMatch = message.id && message.id === filter.id

      if (methodMatch || idMatch) {
        resolve(message)
        listeners = listeners.filter(l => l !== listener)
        ws.onerror = undefined
      }
      else if (!filter.id && !filter.method) {
        resolve(message)
      }
    }

    return promise
  }

  async function send(message: Message): Promise<any> {
    const currentId = id++
    const json = JSON.stringify({ ...message, id: currentId })

    const receiver = receive({ id: currentId })
    ws.send(json)

    return receiver
  }

  await new Promise((resolve, reject) => {
    ws.onerror = reject
    ws.on('open', resolve)
  })

  return { receive, send }
}

function withResolvers() {
  let reject: (error: unknown) => void