allow dial referHook to return application to execute on the other le… (#505)

* allow dial referHook to return application to execute on the other leg; fixes #504

* fix session tracking

* minor logging

* minor

lib/tasks/dial.js

@@ -322,7 +322,7 @@ class TaskDial extends Task {
         const to = parseUri(req.getParsedHeader('Refer-To').uri);
         const by = parseUri(req.getParsedHeader('Referred-By').uri);
         this.logger.info({to}, 'refer to parsed');
-        await cs.requestor.request('verb:hook', this.referHook, {
+        const json = await cs.requestor.request('verb:hook', this.referHook, {
           ...callInfo,
           refer_details: {
             sip_refer_to: req.get('Refer-To'),
@@ -334,6 +334,33 @@ class TaskDial extends Task {
             referred_call_sid
           }
         }, httpHeaders);
+        if (json && Array.isArray(json)) {
+          try {
+            let logger = this.logger;
+            if (isChild) {
+              const {parentLogger} = this.srf.locals;
+              logger = parentLogger.child({callId: cs.callId, callSid: this.sd.callSid});
+            }
+            const tasks = normalizeJambones(logger, json).map((tdata) => makeTask(this.logger, tdata));
+            if (tasks && tasks.length > 0) {
+              const legs = isChild ? ['child', 'parent'] : ['parent', 'child'];
+              this.logger.info(`Dial:handleRefer received REFER on ${legs[0]} leg, setting new app on ${legs[1]} leg`);
+              if (isChild) this.redirect(cs, tasks);
+              else {
+                this.logger.info({tasks: json}, 'Dial:handleRefer - new application for for child leg');
+                const adultingSession = await this.sd.doAdulting({
+                  logger,
+                  application: cs.application,
+                  tasks
+                });
+                /* need to update the callSid of the child with its own (new) AdultingCallSession */
+                sessionTracker.add(adultingSession.callSid, adultingSession);
+              }
+            }
+          } catch (err) {
+            this.logger.info(err, 'Dial:handleRefer - error setting new application after receiving REFER');
+          }
+        }
         res.send(202);
         this.logger.info('DialTask:handleRefer - sent 202 Accepted');
       } catch (err) {