route createCall api requests among active freeswitch servers

app.js

@@ -21,7 +21,8 @@ const {
   retrieveCall,
   deleteCall,
   listCalls,
-  purgeCalls
+  purgeCalls,
+  retrieveSet
 } = require('jambonz-realtimedb-helpers')({
   host: process.env.JAMBONES_REDIS_HOST || 'localhost',
   port: process.env.JAMBONES_REDIS_PORT || 6379
@@ -47,6 +48,7 @@ Object.assign(app.locals, {
   deleteCall,
   listCalls,
   purgeCalls,
+  retrieveSet,
   lookupAppBySid,
   lookupAccountBySid
 });

lib/routes/api/accounts.js

@@ -12,6 +12,7 @@ const preconditions = {
   'update': validateUpdate,
   'delete': validateDelete
 };
+let idx = 0;
 
 function coerceNumbers(callInfo) {
   if (Array.isArray(callInfo)) {
@@ -260,13 +261,20 @@ router.put('/:sid', async(req, res) => {
  */
 router.post('/:sid/Calls', async(req, res) => {
   const sid = req.params.sid;
-  const logger = req.app.locals.logger;
+  const setName = `${(process.env.JAMBONES_CLUSTER_ID || 'default')}:active-fs`;
+  const {retrieveSet, logger} = req.app.locals;
 
   try {
-    const serviceUrl = process.env.JAMBONES_CREATE_CALL_URL;
+    const fs = await retrieveSet(setName);
+    if (0 === fs.length) {
+      logger.info('No available feature servers to handle createCall API request');
+      return res.json({msg: 'no available feature servers at this time'}).status(500);
+    }
+    const ip = fs[fs.length % idx++];
+    const serviceUrl = `http://${ip}:3000/v1/createCall`;
     await validateCreateCall(logger, sid, req);
 
-    logger.debug({payload: req.body}, `sending POST to ${serviceUrl}`);
+    logger.debug({payload: req.body}, `sending createCall API request to to ${ip}`);
     request({
       url: serviceUrl,
       method: 'POST',
@@ -274,11 +282,11 @@ router.post('/:sid/Calls', async(req, res) => {
       body: req.body
     }, (err, response, body) => {
       if (err) {
-        logger.error(err, `Error sending createCall POST to ${serviceUrl}`);
+        logger.error(err, `Error sending createCall POST to ${ip}`);
         return res.sendStatus(500);
       }
       if (response.statusCode !== 201) {
-        logger.error({statusCode: response.statusCode}, `Non-success response returned by createCall ${serviceUrl}`);
+        logger.error({statusCode: response.statusCode}, `Non-success response returned by createCall ${ip}`);
         return res.sendStatus(500);
       }
       res.status(201).json(body);