Voice Integration

Process voice calls, webhooks, and TeXML applications using Edge Compute functions for low-latency call handling.

Handle call events and control calls programmatically:

export default async function(request) {
  const webhook = await request.json();
  
  switch (webhook.event_type) {
    case 'call.initiated':
      return handleCallInitiated(webhook);
    case 'call.answered':
      return handleCallAnswered(webhook);
    case 'call.hangup':
      return handleCallHangup(webhook);
    default:
      return new Response('OK', { status: 200 });
  }
}

async function handleCallInitiated(webhook) {
  // Answer the call
  const response = await fetch(`https://api.telnyx.com/v2/calls/${webhook.data.payload.call_control_id}/actions/answer`, {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${process.env.TELNYX_API_KEY}`,
      'Content-Type': 'application/json'
    }
  });
  
  return new Response('Call answered', { status: 200 });
}

Process TeXML applications at the edge:

<!-- TeXML served from Edge Compute -->
<?xml version="1.0" encoding="UTF-8"?>
<Response>
  <Say>Welcome to our edge-powered call system</Say>
  <Gather numDigits="1" action="https://your-function.edge.telnyx.com/process-dtmf">
    <Say>Press 1 for sales, 2 for support</Say>
  </Gather>
</Response>

export default async function(request) {
  const url = new URL(request.url);
  
  if (url.pathname === '/process-dtmf') {
    const formData = await request.formData();
    const digits = formData.get('Digits');
    
    let responseXML;
    if (digits === '1') {
      responseXML = `
        <Response>
          <Say>Connecting you to sales</Say>
          <Dial>+15551234567</Dial>
        </Response>
      `;
    } else if (digits === '2') {
      responseXML = `
        <Response>
          <Say>Connecting you to support</Say>
          <Dial>+15559876543</Dial>
        </Response>
      `;
    }
    
    return new Response(responseXML, {
      headers: { 'Content-Type': 'application/xml' }
    });
  }
  
  // Default TeXML response
  const defaultXML = `
    <?xml version="1.0" encoding="UTF-8"?>
    <Response>
      <Say>Welcome to our service</Say>
    </Response>
  `;
  
  return new Response(defaultXML, {
    headers: { 'Content-Type': 'application/xml' }
  });
}

Manage conference calls dynamically:

import json
import os

async def handler(request):
    webhook = await request.json()
    
    if webhook['event_type'] == 'conference.participant.joined':
        return await handle_participant_joined(webhook)
    elif webhook['event_type'] == 'conference.participant.left':
        return await handle_participant_left(webhook)
    
    return {"status": "ok"}

async def handle_participant_joined(webhook):
    conference_id = webhook['data']['payload']['conference_id']
    participant_count = webhook['data']['payload']['participant_count']
    
    # Play welcome message for first participant
    if participant_count == 1:
        await play_conference_music(conference_id)
    
    # Announce when participant joins
    await speak_to_conference(
        conference_id,
        f"Participant {participant_count} has joined the conference"
    )
    
    return {"status": "handled"}

async def speak_to_conference(conference_id, message):
    url = f"https://api.telnyx.com/v2/conferences/{conference_id}/actions/speak"
    headers = {
        'Authorization': f'Bearer {os.environ["TELNYX_API_KEY"]}',
        'Content-Type': 'application/json'
    }
    data = {
        'payload': message,
        'voice': 'alice',
        'language': 'en-US'
    }
    
    # Make API call to Telnyx.
    async with aiohttp.ClientSession() as session:
        await session.post(url, headers=headers, json=data)

Learn more about voice integrations in our Voice API documentation.