### Basic <Start><Transcription> usage

Source: https://www.twilio.com/docs/voice/twiml/transcription.md

A minimal example showing how to initiate a real-time transcription session with a status callback URL.

```xml
<Start>
  <Transcription statusCallbackUrl="https://example.com/your-callback-url"/> 
</Start>
```

--------------------------------

### Start a Recording

Source: https://www.twilio.com/docs/voice/twiml/recording.md

Examples of initiating a call recording using the <Start><Recording> TwiML structure across various SDKs and raw XML.

```js
const VoiceResponse = require('twilio').twiml.VoiceResponse;

const response = new VoiceResponse();
const start = response.start();
start.recording({
  channels: 'dual',
  recordingStatusCallback: 'https://example.com/your-callback-url',
});
response.say('The recording has started.');

console.log(response.toString());
```

```py
from twilio.twiml.voice_response import Recording, VoiceResponse, Say, Start

response = VoiceResponse()
start = Start()
start.recording(
    channels='dual',
    recording_status_callback='https://example.com/your-callback-url'
)
response.append(start)
response.say('The recording has started.')

print(response)
```

```cs
using System;
using Twilio.TwiML;
using Twilio.TwiML.Voice;


class Example
{
    static void Main()
    {
        var response = new VoiceResponse();
        var start = new Start();
        start.Recording(channels: "dual",
            recordingStatusCallback: "https://example.com/your-callback-url");
        response.Append(start);
        response.Say("The recording has started.");

        Console.WriteLine(response.ToString());
    }
}
```

```java
import com.twilio.twiml.voice.Recording;
import com.twilio.twiml.VoiceResponse;
import com.twilio.twiml.voice.Say;
import com.twilio.twiml.voice.Start;
import com.twilio.twiml.TwiMLException;


public class Example {
    public static void main(String[] args) {
        Recording recording = new Recording.Builder().channels("dual")
            .recordingStatusCallback("https://example.com/your-callback-url")
            .build();
        Start start = new Start.Builder().recording(recording).build();
        Say say = new Say.Builder("The recording has started.").build();
        VoiceResponse response = new VoiceResponse.Builder().start(start)
            .say(say).build();

        try {
            System.out.println(response.toXml());
        } catch (TwiMLException e) {
            e.printStackTrace();
        }
    }
}
```

```php
<?php
require_once './vendor/autoload.php';
use Twilio\TwiML\VoiceResponse;

$response = new VoiceResponse();
$start = $response->start();
$start->recording(['channels' => 'dual',
    'recordingStatusCallback' => 'https://example.com/your-callback-url']);
$response->say('The recording has started.');

echo $response;
```

```rb
require 'twilio-ruby'

response = Twilio::TwiML::VoiceResponse.new
response.start do |start|
    start.recording(channels: 'dual', recording_status_callback: 'https://example.com/your-callback-url')
end
response.say(message: 'The recording has started.')

puts response
```

```xml
<?xml version="1.0" encoding="UTF-8"?>
<Response>
    <Start>
        <Recording channels="dual" recordingStatusCallback = 
        "https://example.com/your-callback-url" />
    </Start>
    <Say>The recording has started.</Say>
</Response>
```

--------------------------------

### Install Twilio Node.js SDK

Source: https://www.twilio.com/docs/voice/make-calls

Use npm to install the Twilio library for Node.js.

```bash
npm install twilio
```

--------------------------------

### Install Serverless Plugin

Source: https://www.twilio.com/docs/voice/sdks/android/get-started.md

Install the required Twilio Serverless plugin for the CLI.

```bash
twilio plugins:install @twilio-labs/plugin-serverless
```

--------------------------------

### Default TwiML Say Verb

Source: https://www.twilio.com/docs/voice/twiml/say/text-speech.md

Example of a <Say> verb using account-level default voice and language settings.

```xml
<Response>
  <Say>Hello. I am a man!</Say>
</Response>
```

--------------------------------

### Generate SSML with Twilio SDKs

Source: https://www.twilio.com/docs/voice/twiml/say/text-speech.md

Examples demonstrating how to programmatically build complex SSML structures within a <Say> verb using Twilio's official SDKs and raw XML.

```java
import com.twilio.twiml.VoiceResponse;
import com.twilio.twiml.voice.Say;
import com.twilio.twiml.TwiMLException;
import com.twilio.twiml.voice.SsmlW;
import com.twilio.twiml.voice.SsmlSayAs;
import com.twilio.twiml.voice.SsmlProsody;
import com.twilio.twiml.voice.SsmlEmphasis;
import com.twilio.twiml.voice.SsmlS;
import com.twilio.twiml.voice.SsmlPhoneme;
import com.twilio.twiml.voice.SsmlP;
import com.twilio.twiml.voice.SsmlSub;
import com.twilio.twiml.voice.SsmlBreak;

public class Example {
    public static void main(String[] args) {
        SsmlBreak ssmlBreak = new SsmlBreak.Builder().strength(SsmlBreak
            .Strength.X_WEAK).time("100ms").build();
        SsmlPhoneme ssmlPhoneme = new SsmlPhoneme.Builder("Words to speak")
            .alphabet(SsmlPhoneme.Alphabet.X_SAMPA).ph("pɪˈkɑːn").build();
        SsmlP ssmlP = new SsmlP.Builder("Words to speak").build();
        SsmlProsody ssmlProsody = new SsmlProsody.Builder("Words to speak")
            .pitch("-10%").rate("85%").volume("-6dB").build();
        SsmlSub ssmlSub = new SsmlSub.Builder("Words to be substituted")
            .alias("alias").build();
        SsmlS ssmlS = new SsmlS.Builder("Words to speak").build();
        SsmlSayAs ssmlSayAs = new SsmlSayAs.Builder("Words to speak")
            .interpretAs(SsmlSayAs.InterpretAs.SPELL_OUT).build();
        SsmlW ssmlW = new SsmlW.Builder("Words to speak").build();
        SsmlEmphasis ssmlEmphasis = new SsmlEmphasis
            .Builder("Words to emphasize").level(SsmlEmphasis.Level.MODERATE)
            .build();
        Say say = new Say.Builder("Hi").voice(Say.Voice.POLLY_JOANNA)
            .break_(ssmlBreak).emphasis(ssmlEmphasis).p(ssmlP)
            .addText("aaaaaa").phoneme(ssmlPhoneme).addText("bbbbbbb")
            .prosody(ssmlProsody).s(ssmlS).sayAs(ssmlSayAs).sub(ssmlSub)
            .w(ssmlW).build();
        VoiceResponse response = new VoiceResponse.Builder().say(say).build();

        try {
            System.out.println(response.toXml());
        } catch (TwiMLException e) {
            e.printStackTrace();
        }
    }
}
```

```php
<?php
require_once './vendor/autoload.php';
use Twilio\TwiML\VoiceResponse;

$response = new VoiceResponse();
$say = $response->say('Hi', ['voice' => 'Polly.Joanna']);
$say->break_(['strength' => 'x-weak', 'time' => '100ms']);
$say->emphasis('Words to emphasize', ['level' => 'moderate']);
$say->p('Words to speak');
$say->append('aaaaaa');
$say->phoneme('Words to speak', ['alphabet' => 'x-sampa', 'ph' => 'pɪˈkɑːn']);
$say->append('bbbbbbb');
$say->prosody('Words to speak', ['pitch' => '-10%', 'rate' => '85%',
    'volume' => '-6dB']);
$say->s('Words to speak');
$say->say_as('Words to speak', ['interpret-as' => 'spell-out']);
$say->sub('Words to be substituted', ['alias' => 'alias']);
$say->w('Words to speak');

echo $response;
```

```ruby
require 'twilio-ruby'

response = Twilio::TwiML::VoiceResponse.new
response.say(voice: 'Polly.Joanna', message: 'Hi') do |say|
  say.break(strength: 'x-weak', time: '100ms')
  say.emphasis(words: 'Words to emphasize', level: 'moderate')
  say.p(words: 'Words to speak')
  say.add_text('aaaaaa')
  say.phoneme('Words to speak', alphabet: 'x-sampa', ph: 'pɪˈkɑːn')
  say.add_text('bbbbbbb')
  say.prosody(words: 'Words to speak', pitch: '-10%', rate: '85%', volume: '-6dB')
  say.s(words: 'Words to speak')
  say.say_as('Words to speak', interpretAs: 'spell-out')
  say.sub('Words to be substituted', alias: 'alias')
  say.w(words: 'Words to speak')
end

puts response
```

```xml
<Response>
  <Say voice="Polly.Joanna">
    Hi
    <break strength="x-weak" time="100ms"/>
    <emphasis level="moderate">Words to emphasize</emphasis>
    <p>Words to speak</p>
    aaaaaa
    <phoneme alphabet="x-sampa" ph="pɪˈkɑːn">Words to speak</phoneme>
    bbbbbbb
    <prosody pitch="-10%" rate="85%" volume="-6dB">Words to speak</prosody>
    <s>Words to speak</s>
    <say-as interpret-as="spell-out">Words to speak</say-as>
    <sub alias="alias">Words to be substituted</sub>
    <w>Words to speak</w>
  </Say>
</Response>
```

--------------------------------

### Generate SSML with TwiML

Source: https://www.twilio.com/docs/voice/twiml/say/text-speech.md

Example of the resulting TwiML structure when using various SSML tags within a <Say> verb.

```xml
<Response>
  <Say voice="Polly.Joanna">
    Hi
    <break strength="x-weak" time="100ms"/>
    <emphasis level="moderate">Words to emphasize</emphasis>
    <p>Words to speak</p>
    aaaaaa
    <phoneme alphabet="x-sampa" ph="pɪˈkɑːn">Words to speak</phoneme>
    bbbbbbb
    <prosody pitch="-10%" rate="85%" volume="-6dB">Words to speak</prosody>
    <s>Words to speak</s>
    <say-as interpret-as="spell-out">Words to speak</say-as>
    <sub alias="alias">Words to be substituted</sub>
    <w>Words to speak</w>
  </Say>
</Response>
```

--------------------------------

### Language Mapped TwiML Say Verb

Source: https://www.twilio.com/docs/voice/twiml/say/text-speech.md

Example of a <Say> verb using a configured language mapping to automatically select a voice.

```xml
<Response>
  <Say language="en-GB">Hello. I am Emma!</Say>
</Response>
```

--------------------------------

### Initialize Environment Configuration

Source: https://www.twilio.com/docs/voice/sdks/android/get-started.md

Create the .env file from the provided example template.

```bash
cp Server/.env.example Server/.env
```

--------------------------------

### Get Start Time (Android)

Source: https://www.twilio.com/docs/voice/sdks/mobile-preflight-test.md

Call the `getStartTime()` method to get the preflight test start time as a Unix timestamp in milliseconds.

```java
PreflightTest.getStartTime()
```

--------------------------------

### Start the server

Source: https://www.twilio.com/docs/voice/sdks/react-native/reference-components.md

Launches the backend server required for the reference components.

```bash
npm run server
```

--------------------------------

### Get Start Time (iOS)

Source: https://www.twilio.com/docs/voice/sdks/mobile-preflight-test.md

Access the `startTime` property to get the preflight test start time as a Unix timestamp in milliseconds.

```swift
TVOPreflightTest.startTime
```

--------------------------------

### Install Dependencies and Run

Source: https://www.twilio.com/docs/voice/quickstart/server.md

Commands to fetch required modules and execute the Go script.

```bash
go get
```

```bash
go run make_call.go
```

--------------------------------

### Example Start Message

Source: https://www.twilio.com/docs/voice/media-streams/websocket-messages.md

A JSON representation of the start message containing stream metadata and custom parameters.

```json
{
  "event": "start",
  "sequenceNumber": "1",
  "start": {
    "accountSid": "ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
    "streamSid": "MZXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
    "callSid": "CAXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
    "tracks": [ "inbound" ],
    "mediaFormat": { 
        "encoding": "audio/x-mulaw", 
        "sampleRate": 8000, 
        "channels": 1 },
    "customParameters": {
     "FirstName": "Jane",
     "LastName": "Doe",
     "RemoteParty": "Bob"
   }
  },
  "streamSid": "MZXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"
}
```

--------------------------------

### Run the Go Application

Source: https://www.twilio.com/docs/voice/quickstart/server.md

Starts the local web server on the configured port.

```bash
go run main.go
```

--------------------------------

### Initialize Go project

Source: https://www.twilio.com/docs/voice/make-calls

Create a new directory and initialize a Go module for the project.

```bash
mkdir make-call
cd make-call
go mod init make-call
```

--------------------------------

### Retrieve and filter calls by start date

Source: https://www.twilio.com/docs/voice/api/call-resource.md

Examples for listing completed calls filtered by a specific start date across multiple programming languages.

```js
// Download the helper library from https://www.twilio.com/docs/node/install
const twilio = require("twilio"); // Or, for ESM: import twilio from "twilio";

// Find your Account SID and Auth Token at twilio.com/console
// and set the environment variables. See http://twil.io/secure
const accountSid = process.env.TWILIO_ACCOUNT_SID;
const authToken = process.env.TWILIO_AUTH_TOKEN;
const client = twilio(accountSid, authToken);

async function listCall() {
  const calls = await client.calls.list({
    startTime: new Date("2009-07-06 00:00:00"),
    status: "completed",
    limit: 20,
  });

  calls.forEach((c) => console.log(c.end));
}

listCall();
```

```python
# Download the helper library from https://www.twilio.com/docs/python/install
import os
from twilio.rest import Client
from datetime import datetime

# Find your Account SID and Auth Token at twilio.com/console
# and set the environment variables. See http://twil.io/secure
account_sid = os.environ["TWILIO_ACCOUNT_SID"]
auth_token = os.environ["TWILIO_AUTH_TOKEN"]
client = Client(account_sid, auth_token)

calls = client.calls.list(
    status="completed", start_time=datetime(2009, 7, 6, 0, 0, 0), limit=20
)

for record in calls:
    print(record.end)
```

```csharp
// Install the C# / .NET helper library from twilio.com/docs/csharp/install

using System;
using Twilio;
using Twilio.Rest.Api.V2010.Account;
using System.Threading.Tasks;

class Program {
    public static async Task Main(string[] args) {
        // Find your Account SID and Auth Token at twilio.com/console
        // and set the environment variables. See http://twil.io/secure
        string accountSid = Environment.GetEnvironmentVariable("TWILIO_ACCOUNT_SID");
        string authToken = Environment.GetEnvironmentVariable("TWILIO_AUTH_TOKEN");

        TwilioClient.Init(accountSid, authToken);

        var calls = await CallResource.ReadAsync(
            status: CallResource.StatusEnum.Completed,
            startTime: new DateTime(2009, 7, 6, 0, 0, 0, DateTimeKind.Utc),
            limit: 20);

        foreach (var record in calls) {
            Console.WriteLine(record.End);
        }
    }
}
```

```java
// Install the Java helper library from twilio.com/docs/java/install

import java.time.ZoneId;
import java.time.ZonedDateTime;
import com.twilio.Twilio;
import com.twilio.rest.api.v2010.account.Call;
import com.twilio.base.ResourceSet;

public class Example {
    // Find your Account SID and Auth Token at twilio.com/console
    // and set the environment variables. See http://twil.io/secure
    public static final String ACCOUNT_SID = System.getenv("TWILIO_ACCOUNT_SID");
    public static final String AUTH_TOKEN = System.getenv("TWILIO_AUTH_TOKEN");

    public static void main(String[] args) {
        Twilio.init(ACCOUNT_SID, AUTH_TOKEN);
        ResourceSet<Call> calls = Call.reader()
                                      .setStatus(Call.Status.COMPLETED)
                                      .setStartTime(ZonedDateTime.of(2009, 7, 6, 0, 0, 0, 0, ZoneId.of("UTC")))
                                      .limit(20)
                                      .read();

        for (Call record : calls) {
            System.out.println(record.getEnd());
        }
    }
}
```

--------------------------------

### Configure profanityFilter in TwiML

Source: https://www.twilio.com/docs/voice/twiml/transcription.md

Examples showing how to set the profanityFilter attribute when starting a transcription.

```js
const VoiceResponse = require('twilio').twiml.VoiceResponse;

const response = new VoiceResponse();
const start = response.start();
start.transcription({
  statusCallbackUrl: 'https://example.com/your-callback-url',
  profanityFilter: false,
  transcriptionEngine: 'google',
});

console.log(response.toString());
```

```py
from twilio.twiml.voice_response import VoiceResponse, Start, Transcription

response = VoiceResponse()
start = Start()
start.transcription(
    status_callback_url='https://example.com/your-callback-url',
    profanity_filter=False,
    transcription_engine='google')
response.append(start)

print(response)
```

```cs
using System;
using Twilio.TwiML;
using Twilio.TwiML.Voice;


class Example
{
    static void Main()
    {
        var response = new VoiceResponse();
        var start = new Start();
        start.Transcription(statusCallbackUrl: "https://example.com/your-callback-url", profanityFilter: false, transcriptionEngine: "google");
        response.Append(start);

        Console.WriteLine(response.ToString());
    }
}
```

```java
import com.twilio.twiml.VoiceResponse;
import com.twilio.twiml.voice.Start;
import com.twilio.twiml.voice.Transcription;
import com.twilio.twiml.TwiMLException;


public class Example {
    public static void main(String[] args) {
        Transcription transcription = new Transcription.Builder().statusCallbackUrl("https://example.com/your-callback-url").profanityFilter(false).transcriptionEngine("google").build();
        Start start = new Start.Builder().transcription(transcription).build();
        VoiceResponse response = new VoiceResponse.Builder().start(start).build();

        try {
            System.out.println(response.toXml());
        } catch (TwiMLException e) {
            e.printStackTrace();
        }
    }
}
```

```go
package main

import (
	"fmt"

	"github.com/twilio/twilio-go/twiml"
)

func main() {
	twiml, _ := twiml.Voice([]twiml.Element{
		&twiml.VoiceStart{
			InnerElements: []twiml.Element{
				&twiml.VoiceTranscription{
					ProfanityFilter:     "false",
					StatusCallbackUrl:   "https://example.com/your-callback-url",
					TranscriptionEngine: "google",
				},
			},
		},
	})

	fmt.Print(twiml)
}
```

```php
<?php
require_once './vendor/autoload.php';
use Twilio\TwiML\VoiceResponse;

$response = new VoiceResponse();
$start = $response->start();
$start->transcription(['statusCallbackUrl' => 'https://example.com/your-callback-url', 'profanityFilter' => 'false', 'transcriptionEngine' => 'google']);

echo $response;
```

```rb
require 'twilio-ruby'

response = Twilio::TwiML::VoiceResponse.new
response.start do |start|
    start.transcription(status_callback_url: 'https://example.com/your-callback-url', profanity_filter: false, transcription_engine: 'google')
end

puts response
```

```xml
<?xml version="1.0" encoding="UTF-8"?>
<Response>
    <Start>
        <Transcription statusCallbackUrl="https://example.com/your-callback-url" profanityFilter="false" transcriptionEngine="google" /> 
    </Start>      
</Response>
```

--------------------------------

### Initialize Go project and install Twilio library

Source: https://www.twilio.com/docs/voice/quickstart/server.md

Initializes a Go module and installs the Twilio Go helper library.

```bash
go mod init twilio-example && go get github.com/twilio/twilio-go
```

--------------------------------

### Example Call Log JSON Response

Source: https://www.twilio.com/docs/voice/tutorials/how-to-retrieve-call-logs/java.md

This is an example of the JSON structure returned when retrieving a call log. It includes details such as call SID, direction, duration, start and end times, and associated URIs.

```json
{
  "calls": [
    {
      "account_sid": "ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
      "answered_by": "machine_start",
      "api_version": "2010-04-01",
      "caller_name": "callerid1",
      "date_created": "Fri, 18 Oct 2019 17:00:00 +0000",
      "date_updated": "Fri, 18 Oct 2019 17:01:00 +0000",
      "direction": "outbound-api",
      "duration": "4",
      "end_time": "Fri, 18 Oct 2019 17:03:00 +0000",
      "forwarded_from": "calledvia1",
      "from": "+13051416799",
      "from_formatted": "(305) 141-6799",
      "group_sid": "GPdeadbeefdeadbeefdeadbeefdeadbeef",
      "parent_call_sid": "CAdeadbeefdeadbeefdeadbeefdeadbeef",
      "phone_number_sid": "PNdeadbeefdeadbeefdeadbeefdeadbeef",
      "price": "-0.200",
      "price_unit": "USD",
      "sid": "CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0",
      "start_time": "Fri, 18 Oct 2019 17:02:00 +0000",
      "status": "completed",
      "subresource_uris": {
        "notifications": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Notifications.json",
        "recordings": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Recordings.json",
        "payments": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Payments.json",
        "events": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Events.json",
        "siprec": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Siprec.json",
        "streams": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Streams.json",
        "transcriptions": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Transcriptions.json",
        "user_defined_message_subscriptions": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/UserDefinedMessageSubscriptions.json",
        "user_defined_messages": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/UserDefinedMessages.json"
      },
      "to": "+13051913581",
      "to_formatted": "(305) 191-3581",
      "trunk_sid": "TKdeadbeefdeadbeefdeadbeefdeadbeef",
      "uri": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0.json",
      "queue_time": "1000"
    },
    {
      "account_sid": "ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
      "answered_by": "human",
      "api_version": "2010-04-01",
      "caller_name": "callerid2",
      "date_created": "Fri, 18 Oct 2019 16:00:00 +0000",
      "date_updated": "Fri, 18 Oct 2019 16:01:00 +0000",
      "direction": "inbound",
      "duration": "3",
      "end_time": "Fri, 18 Oct 2019 16:03:00 +0000",
      "forwarded_from": "calledvia2",
      "from": "+13051416798",
      "from_formatted": "(305) 141-6798",
      "group_sid": "GPdeadbeefdeadbeefdeadbeefdeadbeee",
      "parent_call_sid": "CAdeadbeefdeadbeefdeadbeefdeadbeee",
      "phone_number_sid": "PNdeadbeefdeadbeefdeadbeefdeadbeee",
      "price": "-0.100",
      "price_unit": "JPY",
      "sid": "CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0",
      "start_time": "Fri, 18 Oct 2019 16:02:00 +0000",
      "status": "completed",
      "subresource_uris": {
        "notifications": "/2010-04-01/Accounts/ACaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/Calls/CAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa0/Notifications.json"
      }
    }
  ]
}
```

--------------------------------

### Initialize SIP Application Template

Source: https://www.twilio.com/docs/voice/sip/quickstart.md

Creates a new project directory using the sip-quickstart template.

```bash
twilio serverless:init acme --template="sip-quickstart"
```

--------------------------------

### Clone and install dependencies

Source: https://www.twilio.com/docs/voice/sdks/react-native/reference-components.md

Initializes the reference components project by cloning the repository and installing required packages.

```bash
git clone https://github.com/twilio/twilio-voice-react-native-reference-components.git
cd twilio-voice-react-native-reference-components
npm install
```

--------------------------------

### List Call Summaries

Source: https://www.twilio.com/docs/voice/voice-insights/api/call/call-summaries-resource.md

Examples of how to retrieve a list of call summaries filtered by carrier and start time.

```go
// Download the helper library from https://www.twilio.com/docs/go/install
package main

import (
	"fmt"
	"github.com/twilio/twilio-go"
	insights "github.com/twilio/twilio-go/rest/insights/v1"
	"os"
)

func main() {
	// Find your Account SID and Auth Token at twilio.com/console
	// and set the environment variables. See http://twil.io/secure
	// Make sure TWILIO_ACCOUNT_SID and TWILIO_AUTH_TOKEN exists in your environment
	client := twilio.NewRestClient()

	params := &insights.ListCallSummariesParams{}
	params.SetToCarrier("AT&T Wireless")
	params.SetStartTime("4h")
	params.SetLimit(20)

	resp, err := client.InsightsV1.ListCallSummaries(params)
	if err != nil {
		fmt.Println(err.Error())
		os.Exit(1)
	} else {
		for record := range resp {
			if resp[record].AccountSid != nil {
				fmt.Println(*resp[record].AccountSid)
			} else {
				fmt.Println(resp[record].AccountSid)
			}
		}
	}
}
```

```php
<?php

// Update the path below to your autoload.php,
// see https://getcomposer.org/doc/01-basic-usage.md
require_once "/path/to/vendor/autoload.php";

use Twilio\Rest\Client;

// Find your Account SID and Auth Token at twilio.com/console
// and set the environment variables. See http://twil.io/secure
$sid = $_ENV["TWILIO_ACCOUNT_SID"];
$token = $_ENV["TWILIO_AUTH_TOKEN"];
$twilio = new Client($sid, $token);

$callSummaries = $twilio->insights->v1->callSummaries->read(
    [
        "toCarrier" => "AT&T Wireless",
        "startTime" => "4h",
    ],
    20,
);

foreach ($callSummaries as $record) {
    print $record->accountSid;
}
```

```ruby
# Download the helper library from https://www.twilio.com/docs/ruby/install
require 'twilio-ruby'

# Find your Account SID and Auth Token at twilio.com/console
# and set the environment variables. See http://twil.io/secure
account_sid = ENV['TWILIO_ACCOUNT_SID']
auth_token = ENV['TWILIO_AUTH_TOKEN']
@client = Twilio::REST::Client.new(account_sid, auth_token)

call_summaries = @client
                 .insights
                 .v1
                 .call_summaries
                 .list(
                   to_carrier: 'AT&T Wireless',
                   start_time: '4h',
                   limit: 20
                 )

call_summaries.each do |record|
   puts record.account_sid
end
```

--------------------------------

### CLI and API Request Examples

Source: https://www.twilio.com/docs/voice/sip/api/sip-credentiallistmapping-resource.md

Command line and raw HTTP request examples for interacting with the resource.

```bash
# Install the twilio-cli from https://twil.io/cli

twilio api:core:sip:domains:auth:calls:credential-list-mappings:list \
   --domain-sid SDXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
```

```bash
curl -X GET "https://api.twilio.com/2010-04-01/Accounts/$TWILIO_ACCOUNT_SID/SIP/Domains/SDXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/Auth/Calls/CredentialListMappings.json?PageSize=20" \
-u $TWILIO_ACCOUNT_SID:$TWILIO_AUTH_TOKEN
```

--------------------------------

### Query Calls with SDKs

Source: https://www.twilio.com/docs/voice/api/call-resource.md

Examples for filtering calls by status and start time using official Twilio helper libraries.

```csharp
// Install the C# / .NET helper library from twilio.com/docs/csharp/install

using System;
using Twilio;
using Twilio.Rest.Api.V2010.Account;
using System.Threading.Tasks;

class Program {
    public static async Task Main(string[] args) {
        // Find your Account SID and Auth Token at twilio.com/console
        // and set the environment variables. See http://twil.io/secure
        string accountSid = Environment.GetEnvironmentVariable("TWILIO_ACCOUNT_SID");
        string authToken = Environment.GetEnvironmentVariable("TWILIO_AUTH_TOKEN");

        TwilioClient.Init(accountSid, authToken);

        var calls = await CallResource.ReadAsync(
            status: CallResource.StatusEnum.Completed,
            startTimeAfter: new DateTime(2009, 7, 6, 0, 0, 0, DateTimeKind.Utc),
            limit: 20);

        foreach (var record in calls) {
            Console.WriteLine(record.End);
        }
    }
}
```

```java
// Install the Java helper library from twilio.com/docs/java/install

import java.time.ZoneId;
import java.time.ZonedDateTime;
import com.twilio.Twilio;
import com.twilio.rest.api.v2010.account.Call;
import com.twilio.base.ResourceSet;

public class Example {
    // Find your Account SID and Auth Token at twilio.com/console
    // and set the environment variables. See http://twil.io/secure
    public static final String ACCOUNT_SID = System.getenv("TWILIO_ACCOUNT_SID");
    public static final String AUTH_TOKEN = System.getenv("TWILIO_AUTH_TOKEN");

    public static void main(String[] args) {
        Twilio.init(ACCOUNT_SID, AUTH_TOKEN);
        ResourceSet<Call> calls = Call.reader()
                                      .setStatus(Call.Status.COMPLETED)
                                      .setStartTimeAfter(ZonedDateTime.of(2009, 7, 6, 0, 0, 0, 0, ZoneId.of("UTC")))
                                      .limit(20)
                                      .read();

        for (Call record : calls) {
            System.out.println(record.getEnd());
        }
    }
}
```

```go
// Download the helper library from https://www.twilio.com/docs/go/install
package main

import (
	"fmt"
	"github.com/twilio/twilio-go"
	api "github.com/twilio/twilio-go/rest/api/v2010"
	"os"
	"time"
)

func main() {
	// Find your Account SID and Auth Token at twilio.com/console
	// and set the environment variables. See http://twil.io/secure
	// Make sure TWILIO_ACCOUNT_SID and TWILIO_AUTH_TOKEN exists in your environment
	client := twilio.NewRestClient()

	params := &api.ListCallParams{}
	params.SetStatus("completed")
	params.SetStartTimeAfter(time.Date(2009, 7, 6, 0, 0, 0, 0, time.UTC))
	params.SetLimit(20)

	resp, err := client.Api.ListCall(params)
	if err != nil {
		fmt.Println(err.Error())
		os.Exit(1)
	} else {
		for record := range resp {
			if resp[record].End != nil {
				fmt.Println(*resp[record].End)
			} else {
				fmt.Println(resp[record].End)
			}
		}
	}
}
```

```php
<?php

// Update the path below to your autoload.php,
// see https://getcomposer.org/doc/01-basic-usage.md
require_once "/path/to/vendor/autoload.php";

use Twilio\Rest\Client;

// Find your Account SID and Auth Token at twilio.com/console
// and set the environment variables. See http://twil.io/secure
$sid = $_ENV["TWILIO_ACCOUNT_SID"];
$token = $_ENV["TWILIO_AUTH_TOKEN"];
$twilio = new Client($sid, $token);

$calls = $twilio->calls->read(
    [
        "status" => "completed",
        "startTimeAfter" => new \DateTime("2009-07-06T00:00:00Z"),
    ],
    20,
);

foreach ($calls as $record) {
    print $record->end;
}
```

```ruby
# Download the helper library from https://www.twilio.com/docs/ruby/install
require 'twilio-ruby'

# Find your Account SID and Auth Token at twilio.com/console
# and set the environment variables. See http://twil.io/secure
account_sid = ENV['TWILIO_ACCOUNT_SID']
auth_token = ENV['TWILIO_AUTH_TOKEN']
@client = Twilio::REST::Client.new(account_sid, auth_token)

calls = @client
        .api
        .v2010
        .calls
        .list(
          status: 'completed',
          start_time_after: Time.new(2009, 7, 6, 0, 0, 0),
          limit: 20
        )

calls.each do |record|
   puts record.end
end
```

--------------------------------

### Initialize .NET Project

Source: https://www.twilio.com/docs/voice/make-calls

Commands to create a new .NET project and install the required Twilio NuGet package.

```bash
mkdir make-call
cd make-call
dotnet new app
dotnet add package Twilio
```

--------------------------------

### Create a unidirectional Stream on a live call

Source: https://www.twilio.com/docs/voice/api/stream-resource.md

Implementation examples for starting a media stream using Node.js and Python SDKs.

```javascript
// Download the helper library from https://www.twilio.com/docs/node/install
const twilio = require("twilio"); // Or, for ESM: import twilio from "twilio";

// Find your Account SID and Auth Token at twilio.com/console
// and set the environment variables. See http://twil.io/secure
const accountSid = process.env.TWILIO_ACCOUNT_SID;
const authToken = process.env.TWILIO_AUTH_TOKEN;
const client = twilio(accountSid, authToken);

async function createStream() {
  const stream = await client
    .calls("CAXXXXXXXXXXXXXXXXXXXXXXXXXXX")
    .streams.create({
      name: "My Media Stream",
      url: "wss://example.com/a-websocket-server",
    });

  console.log(stream.sid);
}

createStream();
```

```python
# Download the helper library from https://www.twilio.com/docs/python/install
import os
from twilio.rest import Client

# Find your Account SID and Auth Token at twilio.com/console
# and set the environment variables. See http://twil.io/secure
account_sid = os.environ["TWILIO_ACCOUNT_SID"]
auth_token = os.environ["TWILIO_AUTH_TOKEN"]
client = Client(account_sid, auth_token)

stream = client.calls("CAXXXXXXXXXXXXXXXXXXXXXXXXXXX").streams.create(
    name="My Media Stream", url="wss://example.com/a-websocket-server"
)

print(stream.sid)
```

--------------------------------

### Configure environment variables

Source: https://www.twilio.com/docs/voice/sdks/javascript/reference-components.md

Example .env file configuration for the reference components.

```text
# Port number to run the server on
PORT=3030

# Twilio account sid
ACCOUNT_SID=ACxxxxxxxxxxxxxx

# Twilio API key
API_KEY_SID=SKxxxxxxxxxxxxxx

# Twilio API secret
API_KEY_SECRET=xxxxxxxxxxxxxx

# Twilio TwiML App SID
# The Voice Request URL must point to one of the /twiml endpoints listed later in this guide.
# For details, see https://www.twilio.com/docs/voice/sdks/javascript#twiml-applications
APP_SID=APxxxxxxxxxxxxxx

# Twilio auth token
AUTH_TOKEN=xxxxxxxxxxxxxx

# Caller ID
CALLER_ID=+11234567890

# Public base URL that Twilio can reach.
# If you run the components locally, use a tunneling service such as ngrok.
# Do not include the scheme (https:// or wss://) in the URL.
CALLBACK_BASE_URL=foo.ngrok.dev

# Default identity to use
DEFAULT_IDENTITY=alice

# twilio-voice-ai-conversation
# See https://platform.openai.com/settings/organization/api-keys
OPENAI_API_KEY="sk-proj......."
```

--------------------------------

### Configure inboundTrackLabel across languages

Source: https://www.twilio.com/docs/voice/twiml/transcription.md

Examples of setting inbound and outbound track labels within a TwiML Start Transcription block.

```js
const VoiceResponse = require('twilio').twiml.VoiceResponse;

const response = new VoiceResponse();
const start = response.start();
start.transcription({
  statusCallbackUrl: 'https://example.com/your-callback-url',
  inboundTrackLabel: 'agent',
  outboundTrackLabel: 'customer',
});

console.log(response.toString());
```

```py
from twilio.twiml.voice_response import VoiceResponse, Start, Transcription

response = VoiceResponse()
start = Start()
start.transcription(
    status_callback_url='https://example.com/your-callback-url',
    inbound_track_label='agent',
    outbound_track_label='customer')
response.append(start)

print(response)
```

```cs
using System;
using Twilio.TwiML;
using Twilio.TwiML.Voice;


class Example
{
    static void Main()
    {
        var response = new VoiceResponse();
        var start = new Start();
        start.Transcription(statusCallbackUrl: "https://example.com/your-callback-url", inboundTrackLabel: "agent", outboundTrackLabel: "customer");
        response.Append(start);

        Console.WriteLine(response.ToString());
    }
}
```

```java
import com.twilio.twiml.VoiceResponse;
import com.twilio.twiml.voice.Start;
import com.twilio.twiml.voice.Transcription;
import com.twilio.twiml.TwiMLException;


public class Example {
    public static void main(String[] args) {
        Transcription transcription = new Transcription.Builder().statusCallbackUrl("https://example.com/your-callback-url").inboundTrackLabel("agent").outboundTrackLabel("customer").build();
        Start start = new Start.Builder().transcription(transcription).build();
        VoiceResponse response = new VoiceResponse.Builder().start(start).build();

        try {
            System.out.println(response.toXml());
        } catch (TwiMLException e) {
            e.printStackTrace();
        }
    }
}
```

```go
package main

import (
	"fmt"

	"github.com/twilio/twilio-go/twiml"
)

func main() {
	twiml, _ := twiml.Voice([]twiml.Element{
		&twiml.VoiceStart{
			InnerElements: []twiml.Element{
				&twiml.VoiceTranscription{
					InboundTrackLabel:  "agent",
					OutboundTrackLabel: "customer",
					StatusCallbackUrl:  "https://example.com/your-callback-url",
				},
			},
		},
	})

	fmt.Print(twiml)
}
```

```php
<?php
require_once './vendor/autoload.php';
use Twilio\TwiML\VoiceResponse;

$response = new VoiceResponse();
$start = $response->start();
$start->transcription(['statusCallbackUrl' => 'https://example.com/your-callback-url', 'inboundTrackLabel' => 'agent', 'outboundTrackLabel' => 'customer']);

echo $response;
```

```rb
require 'twilio-ruby'

response = Twilio::TwiML::VoiceResponse.new
response.start do |start|
    start.transcription(status_callback_url: 'https://example.com/your-callback-url', inbound_track_label: 'agent', outbound_track_label: 'customer')
end

puts response
```

```xml
<?xml version="1.0" encoding="UTF-8"?>
<Response>
    <Start>
        <Transcription statusCallbackUrl="https://example.com/your-callback-url" inboundTrackLabel="agent" outboundTrackLabel="customer" /> 
    </Start>      
</Response>
```

--------------------------------

### Basic <Refer> implementation

Source: https://www.twilio.com/docs/voice/twiml/refer.md

Examples showing how to initiate a SIP transfer using the <Refer> verb across various programming languages.

```js
const VoiceResponse = require('twilio').twiml.VoiceResponse;

const response = new VoiceResponse();
const refer = response.refer();
refer.sip('sip:alice@example.com');

console.log(response.toString());
```

```py
from twilio.twiml.voice_response import Refer, VoiceResponse

response = VoiceResponse()
refer = Refer()
refer.sip('sip:alice@example.com')
response.append(refer)

print(response)
```

```cs
using System;
using Twilio.TwiML;
using Twilio.TwiML.Voice;


class Example
{
    static void Main()
    {
        var response = new VoiceResponse();
        var refer = new Refer();
        refer.Sip(new Uri("sip:alice@example.com"));
        response.Append(refer);

        Console.WriteLine(response.ToString());
    }
}
```

```java
import com.twilio.twiml.voice.Refer;
import com.twilio.twiml.voice.ReferSip;
import com.twilio.twiml.VoiceResponse;
import com.twilio.twiml.TwiMLException;


public class Example {
    public static void main(String[] args) {
        ReferSip refersip = new ReferSip.Builder("sip:alice@example.com")
            .build();
        Refer refer = new Refer.Builder().sip(refersip).build();
        VoiceResponse response = new VoiceResponse.Builder().refer(refer)
            .build();

        try {
            System.out.println(response.toXml());
        } catch (TwiMLException e) {
            e.printStackTrace();
        }
    }
}
```

```go
package main

import (
	"fmt"

	"github.com/twilio/twilio-go/twiml"
)

func main() {
	twiml, _ := twiml.Voice([]twiml.Element{
		&twiml.VoiceRefer{
			InnerElements: []twiml.Element{
				&twiml.VoiceSip{
					SipUrl: "sip:alice@example.com",
				},
			},
		},
	})

	fmt.Print(twiml)
}
```

```php
<?php
require_once './vendor/autoload.php';
use Twilio\TwiML\VoiceResponse;

$response = new VoiceResponse();
$refer = $response->refer();
$refer->sip('sip:alice@example.com');

echo $response;
```

```rb
require 'twilio-ruby'

response = Twilio::TwiML::VoiceResponse.new
response.refer do |refer|
    refer.sip('sip:alice@example.com')
end

puts response
```

```xml
<?xml version="1.0" encoding="UTF-8"?>
<Response>
    <Refer>
        <Sip>sip:alice@example.com</Sip>
    </Refer>
</Response>
```

--------------------------------

### Initialize Ruby Project

Source: https://www.twilio.com/docs/voice/quickstart/server.md

Commands to initialize a Gemfile and install necessary dependencies.

```bash
bundle init
```

```bash
bundle add puma twilio-ruby sinatra
```