send queue leave webhook when dequeued

lib/tasks/dequeue.js

@@ -110,7 +110,8 @@ class TaskDequeue extends Task {
           event: 'dequeue',
           dequeueSipAddress: cs.srf.locals.localSipAddress,
           epUuid: ep.uuid,
-          notifyUrl: getUrl(cs)
+          notifyUrl: getUrl(cs),
+          dequeuer: cs.callInfo.toJSON()
         });
         this.logger.info(`TaskDequeue:_dequeueUrl successfully sent POST to ${url}`);
         bridgeTimer = setTimeout(() => reject(new Error('bridge timeout')), 20000);

lib/tasks/enqueue.js

@@ -263,12 +263,26 @@ class TaskEnqueue extends Task {
    * @param {string} opts.epUuid uuid of the endpoint we need to bridge to
    * @param {string} opts.dequeueSipAddress ip:port of the feature server hosting the other call
    */
-  notifyQueueEvent(cs, opts) {
+  async notifyQueueEvent(cs, opts) {
     if (opts.event === 'dequeue') {
       if (this.bridgeNow) return;
       this.logger.info({opts}, `TaskEnqueue:notifyDequeueEvent: leaving ${this.queueName} because someone wants me`);
       assert(opts.dequeueSipAddress && opts.epUuid && opts.notifyUrl);
       this.emitter.emit('dequeue', opts);
+
+      try {
+        const {lengthOfList} = cs.srf.locals.dbHelpers;
+        const members = await lengthOfList(this.queueName);
+
+        cs.performQueueWebhook({
+          event: 'leave',
+          queue: this.data.name,
+          length: Math.max(members - 1, 0),
+          leaveReason: 'dequeued',
+          leaveTime: Date.now(),
+          dequeuer: opts.dequeuer
+        });
+      } catch (err) {}
     }
     else if (opts.event === 'hangup') {
       this.emitter.emit('hangup');