From 9f158a8cf72b4318b381aee66a27d3b0499c9bfc Mon Sep 17 00:00:00 2001
From: Dave Horton <daveh@beachdognet.com>
Date: Fri, 8 Oct 2021 16:21:47 -0400
Subject: [PATCH] initial WIP to remove freeswitch from media path when not
 recording or transcribing dial calls

---
 lib/session/call-session.js | 11 +++++++++++
 lib/tasks/dial.js           | 28 ++++++++++++++++++++++++++--
 lib/utils/place-outdial.js  | 12 ++++++++++++
 package-lock.json           | 12 ++++++------
 4 files changed, 55 insertions(+), 8 deletions(-)

diff --git a/lib/session/call-session.js b/lib/session/call-session.js
index dd1a1df9..2f7c9410 100644
--- a/lib/session/call-session.js
+++ b/lib/session/call-session.js
@@ -926,6 +926,17 @@ class CallSession extends Emitter {
     };
   }
 
+  async releaseMediaToSBC(remoteSdp) {
+    assert(this.dlg);
+    assert(this.dlg.connected);
+    assert(this.ep);
+    assert(typeof remoteSdp === 'string');
+    await this.dlg.modify(remoteSdp);
+    this.ep.destroy()
+      .then(() => this.ep = null)
+      .catch((err) => this.logger.error({err}, 'releaseMediaToSBC: Error destroying endpoint'));
+  }
+
   /**
    * Called any time call status changes.  This method both invokes the
    * call_status_hook callback as well as updates the realtime database
diff --git a/lib/tasks/dial.js b/lib/tasks/dial.js
index 5d8eff14..c6d6c8e6 100644
--- a/lib/tasks/dial.js
+++ b/lib/tasks/dial.js
@@ -130,6 +130,8 @@ class TaskDial extends Task {
 
   get name() { return TaskName.Dial; }
 
+  get canReleaseMedia() { return !this.dtmfHook && !this.listenTask && !this.transcribeTask; }
+
   async exec(cs) {
     await super.exec(cs);
     try {
@@ -255,7 +257,8 @@ class TaskDial extends Task {
     debug(`Dial:__initializeInbound allocated ep for incoming call: ${ep.uuid}`);
 
     /* send outbound legs back to the same SBC (to support static IP feature) */
-    if (!this.proxy) this.proxy = `${cs.req.source_address}:${cs.req.source_port};transport=tcp`;
+    //if (!this.proxy) this.proxy = `${cs.req.source_address}:${cs.req.source_port};transport=tcp`;
+    if (!this.proxy) this.proxy = `${cs.req.source_address}:${cs.req.source_port}`;
 
     if (this.dialMusic) {
       // play dial music to caller while we outdial
@@ -395,7 +398,7 @@ class TaskDial extends Task {
   }
 
   _connectSingleDial(cs, sd) {
-    if (!this.bridged) {
+    if (!this.bridged && !this.canReleaseMedia) {
       this.logger.debug('Dial:_connectSingleDial bridging endpoints');
       if (this.epOther) {
         this.epOther.api('uuid_break', this.epOther.uuid);
@@ -457,6 +460,9 @@ class TaskDial extends Task {
 
     if (this.transcribeTask) this.transcribeTask.exec(cs, this.ep);
     if (this.listenTask) this.listenTask.exec(cs, this.ep);
+
+    /* if we can release the media back to the SBC, do so now */
+    if (this.canReleaseMedia) this._releaseMedia(cs, sd);
   }
 
   _bridgeEarlyMedia(sd) {
@@ -468,6 +474,24 @@ class TaskDial extends Task {
     }
   }
 
+  /**
+   * Release the media from freeswitch
+   * @param {*} cs
+   * @param {*} sd
+   */
+  async _releaseMedia(cs, sd) {
+    assert(cs.ep && sd.ep);
+
+    try {
+      this.logger.info('Dial:_releaseMedia - releasing media from freewitch since we can');
+      const aLegSdp = cs.ep.remote.sdp;
+      const bLegSdp = sd.ep.remote.sdp;
+      await Promise.all[sd.releaseMediaToSBC(aLegSdp), cs.releaseMediaToSBC(bLegSdp)];
+      this.epOther = null;
+    } catch (err) {
+      this.logger.info({err}, 'Dial:_releaseMedia error');
+    }
+  }
 }
 
 module.exports = TaskDial;
diff --git a/lib/utils/place-outdial.js b/lib/utils/place-outdial.js
index 93939536..05020e9e 100644
--- a/lib/utils/place-outdial.js
+++ b/lib/utils/place-outdial.js
@@ -62,6 +62,7 @@ class SingleDialer extends Emitter {
     opts = opts || {};
     opts.headers = opts.headers || {};
     opts.headers = {...opts.headers, 'X-Call-Sid': this.callSid};
+    this.ms = ms;
     let uri, to;
     try {
       switch (this.target.type) {
@@ -313,6 +314,17 @@ class SingleDialer extends Emitter {
     return cs;
   }
 
+  async releaseMediaToSBC(remoteSdp) {
+    assert(this.dlg);
+    assert(this.dlg.connected);
+    assert(this.ep);
+    assert(typeof remoteSdp === 'string');
+    await this.dlg.modify(remoteSdp);
+    this.ep.destroy()
+      .then(() => this.ep = null)
+      .catch((err) => this.logger.error({err}, 'releaseMediaToSBC: Error destroying endpoint'));
+  }
+
   _notifyCallStatusChange({callStatus, sipStatus, duration}) {
     assert((typeof duration === 'number' && callStatus === CallStatus.Completed) ||
       (!duration && callStatus !== CallStatus.Completed),
diff --git a/package-lock.json b/package-lock.json
index 5ed4a2b1..6ebb4721 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -592,9 +592,9 @@
       }
     },
     "node_modules/ansi-regex": {
-      "version": "5.0.0",
-      "resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-5.0.0.tgz",
-      "integrity": "sha512-bY6fj56OUQ0hU1KjFNDQuJFezqKdrAyFdIevADiqrWHwSlbmBNMHp5ak2f40Pm8JTFyM2mqxkG6ngkHO11f/lg==",
+      "version": "5.0.1",
+      "resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-5.0.1.tgz",
+      "integrity": "sha512-quJQXlTSUGL2LH9SUXo8VwsY4soanhgo6LNSm84E1LBcE8s3O0wpdiRzyR9z/ZZJMlMWv37qOOb9pdJlMUEKFQ==",
       "dev": true,
       "engines": {
         "node": ">=8"
@@ -5239,9 +5239,9 @@
       "dev": true
     },
     "ansi-regex": {
-      "version": "5.0.0",
-      "resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-5.0.0.tgz",
-      "integrity": "sha512-bY6fj56OUQ0hU1KjFNDQuJFezqKdrAyFdIevADiqrWHwSlbmBNMHp5ak2f40Pm8JTFyM2mqxkG6ngkHO11f/lg==",
+      "version": "5.0.1",
+      "resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-5.0.1.tgz",
+      "integrity": "sha512-quJQXlTSUGL2LH9SUXo8VwsY4soanhgo6LNSm84E1LBcE8s3O0wpdiRzyR9z/ZZJMlMWv37qOOb9pdJlMUEKFQ==",
       "dev": true
     },
     "ansi-styles": {