Transcribe streaming audio from a microphone in TypeScript

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import { Readable } from 'stream'
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import { AssemblyAI } from 'assemblyai'
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import recorder from 'node-record-lpcm16'
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const run = async () => {
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  const client = new AssemblyAI({
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    apiKey: '<YOUR_API_KEY>'
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  })
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  const transcriber = client.realtime.transcriber({
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    sampleRate: 16_000
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  })
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  transcriber.on('open', ({ sessionId }) => {
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    console.log(`Session opened with ID: ${sessionId}`)
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  })
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  transcriber.on('error', (error) => {
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    console.error('Error:', error)
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  })
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  transcriber.on('close', (code, reason) =>
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    console.log('Session closed:', code, reason)
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  )
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  transcriber.on('transcript', (transcript) => {
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    if (!transcript.text) {
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      return
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    }
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    if (transcript.message_type === 'PartialTranscript') {
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      console.log('Partial:', transcript.text)
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    } else {
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      console.log('Final:', transcript.text)
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    }
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  })
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  try {
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    console.log('Connecting to real-time transcript service')
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    await transcriber.connect()
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    console.log('Starting recording')
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    const recording = recorder.record({
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      channels: 1,
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      sampleRate: 16_000,
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      audioType: 'wav' // Linear PCM
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    })
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    Readable.toWeb(recording.stream()).pipeTo(transcriber.stream())
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    // Stop recording and close connection using Ctrl-C.
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    process.on('SIGINT', async function () {
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      console.log()
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      console.log('Stopping recording')
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      recording.stop()
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      console.log('Closing real-time transcript connection')
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      await transcriber.close()
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      process.exit()
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    })
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  } catch (error) {
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    console.error(error)
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  }
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}
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run()

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try {
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  console.log('Connecting to real-time transcript service')
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  await transcriber.connect()
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} catch (error) {
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  console.error(error)
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}

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process.on("SIGINT", async function () {
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  console.log();
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  console.log("Stopping recording");
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  recording.stop();
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  console.log("Closing real-time transcript connection");
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  await transcriber.close();
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  process.exit();
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});