Improved audio connect and transfer

[capilkey]

This PR changes how the client determines when it's in the echo test and when the transfer to the conference is successful. The new method is to have the FreeSWITCH dialplan send back DTMF INFO messages so that we don't have to rely on guessing or the server components.

In order for this to work there are some dialplan changes required. The first two files already exist and need to be changed and the third file is new.

/opt/freeswitch/conf/dialplan/default/bbb_conference.xml

<include>
    <extension name="bbb_conferences_ws">
      <condition field="${bbb_authorized}" expression="true" break="on-false"/>
      <condition field="${sip_via_protocol}" expression="^wss?$"/>
      <condition field="destination_number" expression="^(\d{5,6})$">
        <action application="set" data="jitterbuffer_msec=20:400"/>
        <action application="answer"/>
        <action application="set" data="dtmf_type=info"/>
        <action application="send_dtmf" data="0"/>
        <action application="conference" data="$1@cdquality"/>
      </condition>
    </extension>
    <extension name="bbb_conferences">
      <condition field="${bbb_authorized}" expression="true" break="on-false"/>
      <condition field="destination_number" expression="^(\d{5,6})$">
        <action application="set" data="jitterbuffer_msec=20:400"/>
        <action application="answer"/>
        <action application="conference" data="$1@cdquality"/>
      </condition>
    </extension>
</include>

/opt/freeswitch/conf/dialplan/default/bbb_echo_test.xml

<include>
  <extension name="bbb_echo_test_direct">
    <condition field="${bbb_authorized}" expression="true" break="on-false"/>
    <condition field="destination_number" expression="^9196$|^9196(\d{5,6})$">
      <action application="set" data="vbridge=$1"/>
      <action application="answer"/>
      <action application="set" data="bbb_from_echo=true"/>
      <action application="set" data="dtmf_type=info"/>
      <action application="send_dtmf" data="0"/>
      <action application="bind_digit_action" data="direct_from_echo,1,exec:execute_extension,ECHO_TO_CONFERENCE XML default"/>
      <action application="sleep" data="500"/>
      <action application="echo"/>
    </condition>
  </extension>
</include>

/opt/freeswitch/conf/dialplan/default/bbb_echo_to_conference.xml

<include>
  <extension name="ECHO_TO_CONFERENCE">
    <condition field="${bbb_from_echo}" expression="true" break="on-false"/>
    <condition field="destination_number" expression="^(ECHO_TO_CONFERENCE)$">
      <action application="set" data="jitterbuffer_msec=20:400"/>
      <action application="answer"/>
      <action application="set" data="dtmf_type=info"/>
      <action application="send_dtmf" data="7"/>
      <action application="conference" data="${vbridge}@cdquality"/>
    </condition>
  </extension>
</include>

Thanks to @hostbbb for the assist on the dialplan changes.

[hostbbb]

So no change to Flash webrtc bridge code? will flash client still work with new dialplan?

[capilkey]

The new dialplans just gives more information to the client that it can optionally use. The Flash client's bridge code will just ignore the incoming DTMF and have the same detection as it had before.