feat: add nuance, riva, ibm

lib/get-nuance-access-token.js

@@ -0,0 +1,49 @@
+const formurlencoded = require('form-urlencoded');
+const {Pool} = require('undici');
+const pool = new Pool('https://auth.crt.nuance.com');
+const {makeNuanceKey, makeBasicAuthHeader, noopLogger} = require('./utils');
+const debug = require('debug')('jambonz:realtimedb-helpers');
+const HTTP_TIMEOUT = 5000;
+
+async function getNuanceAccessToken(client, logger, clientId, secret, scope) {
+  logger = logger || noopLogger;
+  try {
+    const key = makeNuanceKey(clientId, secret, scope);
+    const access_token = await client.getAsync(key);
+    if (access_token) return {access_token, servedFromCache: true};
+
+    /* access token not found in cache, so fetch it from Nuance */
+    const payload = {
+      grant_type: 'client_credentials',
+      scope
+    };
+    const auth = makeBasicAuthHeader(clientId, secret);
+    const {statusCode, headers, body} =  await pool.request({
+      path: '/oauth2/token',
+      method: 'POST',
+      headers: {
+        ...auth,
+        'Content-Type': 'application/x-www-form-urlencoded'
+      },
+      body: formurlencoded(payload),
+      timeout: HTTP_TIMEOUT,
+      followRedirects: false
+    });
+
+    if (200 !== statusCode) {
+      logger.debug({statusCode, headers, body: body.text()}, 'error fetching access token from Nuance');
+      const err = new Error();
+      err.statusCode = statusCode;
+      throw err;
+    }
+    const json = await body.json();
+    await client.set(key, json.access_token, 'EX', json.expires_in - 30);
+    return {...json, servedFromCache: false};
+  } catch (err) {
+    debug(err, `getNuanceAccessToken: Error retrieving Nuance access token for client_id ${clientId}`);
+    logger.error(err, `getNuanceAccessToken: Error retrieving Nuance access token for client_id ${clientId}`);
+    throw err;
+  }
+}
+
+module.exports = getNuanceAccessToken;