support deepgramflux tts (#148)

lib/synth-audio.js

@@ -80,7 +80,8 @@ async function synthAudio(client, createHash, retrieveHash, logger, stats, { acc
   logger = logger || noopLogger;
 
   assert.ok(['google', 'aws', 'polly', 'microsoft', 'wellsaid', 'nvidia', 'elevenlabs',
-    'whisper', 'deepgram', 'rimelabs', 'cartesia', 'inworld', 'resemble', 'murf', 'xai'].includes(vendor) ||
+    'whisper', 'deepgram', 'deepgramflux', 'rimelabs', 'cartesia', 'inworld', 'resemble', 'murf', 'xai']
+    .includes(vendor) ||
   vendor.startsWith('custom'),
   `synthAudio supported vendors are google, aws, microsoft, nvidia and wellsaid ..etc, not ${vendor}`);
   if ('google' === vendor) {
@@ -124,6 +125,11 @@ async function synthAudio(client, createHash, retrieveHash, logger, stats, { acc
     if (!credentials.deepgram_tts_uri) {
       assert.ok(credentials.api_key, 'synthAudio requires api_key when deepgram is used');
     }
+  } else if ('deepgramflux' === vendor) {
+    // Deepgram Flux TTS (/v2/speak); the flux model rides on `voice`/`model`
+    if (!credentials.deepgram_tts_uri) {
+      assert.ok(credentials.api_key, 'synthAudio requires api_key when deepgramflux is used');
+    }
   } else if ('xai' === vendor) {
     assert.ok(credentials.api_key, 'synthAudio requires api_key when xai is used');
   } else if ('cartesia' === vendor) {
@@ -230,6 +236,10 @@ async function synthAudio(client, createHash, retrieveHash, logger, stats, { acc
         audioData = await synthDeepgram(logger, {credentials, stats, model, key, text,
           renderForCaching, disableTtsStreaming, disableTtsCache});
         break;
+      case 'deepgramflux':
+        audioData = await synthDeepgramFlux(logger, {credentials, stats, model: model || voice, key, text,
+          renderForCaching, disableTtsStreaming, disableTtsCache});
+        break;
       case 'xai':
         audioData = await synthXai(logger, {
           credentials, options, stats, language, voice, key, text, renderForCaching, disableTtsStreaming,
@@ -1140,6 +1150,50 @@ const synthDeepgram = async(logger, {credentials, stats, model, key, text, rende
   }
 };
 
+// Deepgram Flux TTS — the conversation-native model served from /v2/speak.
+// Streaming rides the mediajam deepgramflux dialect via a say: filePath; the
+// batch/cache path POSTs to /v2/speak (mp3 is batch-only for Flux).
+const synthDeepgramFlux = async(logger, {credentials, stats, model, key, text, renderForCaching,
+  disableTtsStreaming, disableTtsCache}) => {
+  const {api_key, deepgram_tts_uri} = credentials;
+  if (!JAMBONES_DISABLE_TTS_STREAMING && !renderForCaching && !disableTtsStreaming) {
+    let params = '{';
+    params += `api_key=${api_key}`;
+    params += `,playback_id=${key}`;
+    params += ',vendor=deepgramflux';
+    params += `,voice=${model}`;
+    params += `,write_cache_file=${disableTtsCache ? 0 : 1}`;
+    if (deepgram_tts_uri) params += `,endpoint=${deepgram_tts_uri}`;
+    params += '}';
+
+    return {
+      filePath: `say:${params}${text.replace(/\n/g, ' ')}`,
+      servedFromCache: false,
+      rtt: 0
+    };
+  }
+  try {
+    const post = bent(deepgram_tts_uri || 'https://api.deepgram.com', 'POST', 'buffer', {
+      // on-premise deepgram does not require to have api_key
+      ...(api_key && {'Authorization': `Token ${api_key}`}),
+      'Accept': 'audio/mpeg',
+      'Content-Type': 'application/json'
+    });
+    const audioContent = await post(`/v2/speak?model=${model}`, {
+      text
+    });
+    return {
+      audioContent,
+      extension: 'mp3',
+      sampleRate: 8000
+    };
+  } catch (err) {
+    logger.info({err}, 'synth Deepgram Flux returned error');
+    stats.increment('tts.count', ['vendor:deepgramflux', 'accepted:no']);
+    throw err;
+  }
+};
+
 const synthXai = async(logger, {
   credentials, options, stats, language, voice, key, text, renderForCaching, disableTtsStreaming, disableTtsCache
 }) => {

test/synth.js

@@ -1118,6 +1118,34 @@ test('Deepgram speech synth tests', async(t) => {
   client.quit();
 })
 
+test('Deepgram Flux speech synth tests', async(t) => {
+  const fn = require('..');
+  const {synthAudio, client} = fn(opts, logger);
+
+  if (!process.env.DEEPGRAM_API_KEY) {
+    t.pass('skipping Deepgram Flux speech synth tests since DEEPGRAM_API_KEY');
+    return t.end();
+  }
+  const text = 'Hi there and welcome to jambones!';
+  try {
+    const opts = await synthAudio(stats, {
+      vendor: 'deepgramflux',
+      credentials: {
+        api_key: process.env.DEEPGRAM_API_KEY
+      },
+      model: process.env.DEEPGRAM_FLUX_MODEL || 'flux-alexis-en',
+      text,
+      renderForCaching: true
+    });
+    t.ok(!opts.servedFromCache, `successfully synthesized deepgramflux audio to ${opts.filePath}`);
+
+  } catch (err) {
+    console.error(JSON.stringify(err));
+    t.end(err);
+  }
+  client.quit();
+});
+
 test('xai speech synth tests', async(t) => {
   const fn = require('..');
   const {synthAudio, client} = fn(opts, logger);