feat: add account_sid to tts hash key and confiurable TTL for cached file

lib/purge-tts-cache.js

@@ -11,7 +11,8 @@ const debug = require('debug')('jambonz:realtimedb-helpers');
  * @param {string} opts.text - text or ssml to synthesize
  * @returns {object} result - {error, purgedCount}
  */
-async function purgeTtsCache(client, logger, {all, vendor, language, voice, deploymentId, engine, text} = {all: true}) {
+async function purgeTtsCache(client, logger, {all, account_sid, vendor,
+  language, voice, deploymentId, engine, text} = {all: true}) {
   logger = logger || noopLogger;
 
   let purgedCount = 0, error;
@@ -21,8 +22,13 @@ async function purgeTtsCache(client, logger, {all, vendor, language, voice, depl
       const keys = await client.keysAsync('tts:*');
       purgedCount = await client.delAsync(keys);
 
-    } else {
+    } else if (account_sid && !vendor && !language && !voice && !engine && !text) {
+      const keys = await client.keysAsync(`tts:${account_sid}:*`);
+      purgedCount = await client.delAsync(keys);
+    }
+    else {
       const key = makeSynthKey({
+        account_sid,
         vendor,
         language: language || '',
         voice: voice || deploymentId,

lib/synth-audio.js

@@ -32,7 +32,7 @@ const {
 const {SynthesizeSpeechRequest} = require('../stubs/riva/proto/riva_tts_pb');
 const {AudioEncoding} = require('../stubs/riva/proto/riva_audio_pb');
 const debug = require('debug')('jambonz:realtimedb-helpers');
-const EXPIRES = 3600 * 24; // cache tts for 24 hours
+const EXPIRES = process.env.JAMBONES_TTS_CACHE_DURATION_MINS || 3600 * 24; // cache tts for 24 hours
 const TMP_FOLDER = '/tmp';
 
 /**
@@ -95,8 +95,9 @@ async function synthAudio(client, logger, stats, {
   } else  if (vendor.startsWith('custom')) {
     assert.ok(credentials.custom_tts_url, `synthAudio requires custom_tts_url in credentials when ${vendor} is used`);
   }
-
+  const account_sid = credentials.account_sid;
   const key = makeSynthKey({
+    account_sid,
     vendor,
     language: language || '',
     voice: voice || deploymentId,

lib/utils.js

@@ -16,10 +16,10 @@ const debug = require('debug')('jambonz:realtimedb-helpers');
  */
 //const nuanceClientMap = new Map();
 
-function makeSynthKey({vendor, language, voice, engine = '', text}) {
+function makeSynthKey({account_sid = '', vendor, language, voice, engine = '', text}) {
   const hash = crypto.createHash('sha1');
   hash.update(`${language}:${vendor}:${voice}:${engine}:${text}`);
-  return `tts:${hash.digest('hex')}`;
+  return `tts${account_sid ? (':' + account_sid) : ''}:${hash.digest('hex')}`;
 }
 
 const noopLogger = {

test/synth.js

@@ -427,5 +427,35 @@ test('TTS Cache tests', async(t) => {
     t.end(err);
   }
 
+  try {
+    // clear cache
+    await purgeTtsCache();
+    // save some random tts keys to cache
+    const minRecords = 8;
+    const account_sid = "12412512_cabc_5aff"
+    const account_sid2 = "22412512_cabc_5aff"
+    for (const i in Array(minRecords).fill(0)) {
+      await client.setAsync(makeSynthKey({account_sid, vendor: i, language: i, voice: i, engine: i, text: i}), i);
+    }
+    for (const i in Array(minRecords).fill(0)) {
+      await client.setAsync(makeSynthKey({account_sid: account_sid2, vendor: i, language: i, voice: i, engine: i, text: i}), i);
+    }
+    const {purgedCount} = await purgeTtsCache({account_sid});
+    t.equal(purgedCount, minRecords, `successfully purged at least ${minRecords} tts records from cache for account_sid:${account_sid}`);
+
+    let cached = (await client.keysAsync('tts:*')).length;
+    t.equal(cached, minRecords, `successfully purged all tts records from cache for account_sid:${account_sid}`);
+
+    const {purgedCount: purgedCount2} = await purgeTtsCache({account_sid: account_sid2});
+    t.equal(purgedCount2, minRecords, `successfully purged at least ${minRecords} tts records from cache for account_sid:${account_sid2}`);
+
+    cached = (await client.keysAsync('tts:*')).length;
+    t.equal(cached, 0, `successfully purged all tts records from cache`);
+
+  } catch (err) {
+    console.error(JSON.stringify(err));
+    t.end(err);
+  }
+
   client.quit();
 });