const axios = require('axios');

let config = {
  method: 'get',
  url: 'https://api.developers.krisp.ai/v2/sdk/voice-translation/session/token?expiration_ttl=100'
	// expiration_ttl is in MINUTES. Min: 5, Max: 1440 (24h).
  headers: { 
    'Authorization': 'api-key API_KEY'
  }
};

axios.request(config)
  .then((response) => {
  // response.data.data = {
  //   session_key: "session_key_...",
  //   expires_at: "2026-05-04T12:00:00.000Z",
  //   key_id: 123,
  //   status: "active",
  //   type: "session"
  // }
	const SESSION_KEY = response.data.data.session_key;
})
.catch((error) => {
  console.log(error);
});

# 1. Get a short-lived session key (or have your backend mint one).
session_key = get_vt_session_key(API_KEY)["session_key"]

# 2. Build a session config.
config = VtSessionConfig(
    auth_token           = session_key,
    input_language_code  = "en-US",         # BCP-47, source
    output_language_code = "fr-FR",         # BCP-47, target
    voice                = VtVoice.FEMALE,   # "male" | "female"
    # input/output_sample_rate, input_frame_duration default to 16 kHz / 20 ms
    custom_vocabulary    = VtCustomVocabularyData(
        vocabulary = ["Krisp", "AcmeCorp"], # ASR boost for domain terms (optional)
        dictionary = {                      # force specific translations (optional)
            "hello": "bonjour",
            "goodbye": "au revoir",
        },
    ),
    metadata             = VtSessionMetadata(
        reference_id = "your-reference-id",  # optional correlation id for support
    ),
    # Optional opt-in feature flags (default False), e.g.:
    # background_voice_cancellation = True,    # filter other voices server-side
)

# 3. Open the session; register five callbacks. They all fire on the SDK's
#    background thread, so route results through a queue if you need them
#    back on the main thread.
vt = Vt.create(
    config,
    original_transcript_callback   = on_source_text,       # interim + final source text
    translated_transcript_callback = on_target_text,       # interim + final target text
    audio_result_callback          = on_translated_audio,  # raw int16 PCM bytes
    event_callback                 = on_event,             # INPUT_ALLOWED / INPUT_NOT_ALLOWED
    error_callback                 = on_error,             # VtErrorType
)

# 4. Stream audio in real time. One PCM chunk per `input_frame_duration` ms.
#    16 kHz mono s16le => 640 bytes per 20 ms chunk.
for chunk in pcm_chunks:
    vt.process(chunk)
    sleep(0.020)                       # pace in real time — required by the API

# 5. Drain trailing events, then close.
sleep(2.0)                             # let the final transcript / translation / audio land
vt.close()                             # idempotent

{
  "config": {
    "audio": {
      "format": "pcm_s16le", // pcm_s16le or Opus
      "sample_rate": 16000,
      "channels": 1
    },
    "source_language": "en-US",
    "target_language": "fr-FR",
    "voice": "male" | "female",
    "vocabulary": ["special", "domain", "terms"],
    "translation_dictionary": [
      { "source": "referral", "target": "référence" },
      { "source": "copay", "target": "quote-part" },
      { "source": "email", "target": "courriel" }
    ],
    "transcript": {
      "interim": true,
      "final": true,
      "translate": true
    },
	  "features": {
	    "background_voice_cancellation": true
	  },
    "metadata": {
      "reference_id": "your-reference-id"
    }
  }
}

{
  "transcript": {
    "text": "Hello, how are you?",
    "final": false,
    "start": "2026-03-25T19:24:45.370+00:00",
    "duration": 436,
    "utterance_id": "daslkndlkans",
    "reference_id": "askdnl"
  }
}

{
  "translate": {
    "text": "¿Hola, cómo estás?",
    "final": true,
    "utterance_id": "daslkndlkans",
    "reference_id": "askdnl"
  }
}

{
  "error": {
    "code": 400,
    "reason": "Bad request",
    "description": "Actual description of the error",
    "reference_id": "askdnl"
  }
}

GET /voice-translation/languages

{
  "success": true,
  "code": 0,
  "data": [
    {
      "name": "English (United States)",
      "language_code": "en-US"
    },
    {
      "name": "French",
      "language_code": "fr-FR"
    },
    {
      "name": "German",
      "language_code": "de-DE"
    }
  ],
  "req_id": "..."
}