Lua: send SMS via Flowroute when voicemail is received

Brought to you by Steven Schoch on the FreeSwitch mailing list in June 2016.

Assuming Lua is already installed on your system and configured with FreeSwitch.

If you don't have an account with flowroute.com, sign up and enable the developer account needed. At the current time, this can be found under Preferences > API control.

You may need to visit Here to setup the credentials. You will also need to purchase a DID from Flowroute so you can actually send SMS messages.

Here's the script that does the actual processing. As you may have guessed, load this to /usr/local/freeswitch/scripts and read below for the rest of the configuration needed. Add your user and password in the url section.

voicemail-event.lua

--[[
     This script is called by configuration in autoload_configs/lua.conf.xml.
     It is called on a "vm:maintenance" event.
]]

-- The following is specifc to the Flowroute SMS API,
-- documented at https://developer.flowroute.com/docs/messaging
url = "https://user:password@api.flowroute.com/v2/messages"

action = event:getHeader("VM-Action")
if action ~= "leave-message" then return end
user = event:getHeader("VM-User")
domain = event:getHeader("VM-Domain")
caller_id_name = event:getHeader("VM-Caller-ID-Name")
caller_id_number = event:getHeader("VM-Caller-ID-Number")
--[[ We don't care about these:
file_path = event:getHeader("VM-File-Path")
flags = event:getHeader("VM-Flags")
folder = event:getHeader("VM-Folder")
uuid = event:getHeader("VM-UUID")
--]]
message_len = event:getHeader("VM-Message-Len")
timestamp = event:getHeader("VM-Timestamp")
api = freeswitch.API();
from = api:execute("user_data", user .. "@" .. domain ..  " var outbound_caller_id_number")
to = api:execute("user_data", user .. "@" .. domain .. " param vm-notify-sms")
if to == "" then return end

if caller_id_name == ''
        or caller_id_name == 'UNKNOWN'
        or caller_id_name == 'UNASSIGNED'
        or caller_id_name == 'WIRELESS CALLER'
        or caller_id_name == 'TOLL FREE CALL'
        or caller_id_name == 'Anonymous'
        or caller_id_name == 'Unavailable'
        then caller_id_name = nil end
if caller_id_number == ''
        then caller_id_number = nil end
message = "Voicemail "
if caller_id_name
        then message = message .. "from " .. caller_id_name .. " (" ..  caller_id_number .. ")"
        elseif caller_id_number
        then message = message .. "from " .. caller_id_number end
message = message .. " at " .. os.date("%a %H:%M", timestamp)
message = message .. " length " .. message_len .. " seconds"
message = message .. " to box " .. user
message = message .. "."
-- Add JSON string escapes to the message
message = string.gsub(message, "([\\\"'])", "\\%1")
-- Send the text
data = '{ "to": "' .. to .. '", "from": "' .. from .. '", "body": "' .. message .. '"}'
api:execute("curl", url .. " content-type application/json post '" .. data .. "'")

Edit /usr/src/freeswitch/modules.conf and enable applications/curl:

modules.conf

applications/mod_curl

Compile FreeSwitch as usual:

Build FreeSWITCH

make
make install
# Or if you're following master:
make current

Now you will need to have mod_curl load when you start FreeSwitch. Edit /usr/local/freeswitch/conf/autoload_configs/modules.conf.xml:

modules.conf.xml:

<load module="mod_curl"/>

Uncomment mod_curl and make it look like the above.

Add the line below to your extension, such as /usr/local/freeswitch/conf/directory/default/1001.xml:

1001.xml

<param name="vm-notify-sms" value="1202478xxxx"/>

Be sure to add this within the <params> tag and not <variables>.

This will be the telephone number where you want to receive the alert. Replace it with a legitimate phone number.

In the same file, you will need to consider adding your Flowroute number that you purchased. You must send from a Flowroute phone number that's associated with your account.

Caller ID

<variable name="outbound_caller_id_number" value="1468856xxxx"/>

You can also edit /usr/local/freeswitch/conf/vars.xml and have a global caller ID, if desired.

Add this line to /usr/local/freeswitch/conf/autoload_configs/lua.conf.xml:

lua.conf.xml

<hook event="CUSTOM" subclass="vm::maintenance" script="voicemail-event.lua"/>

Ensure this is somewhere between the beginning and ending <settings> tags.

TEST:

fs_cli to the Freeswitch server, make a call and look for something like this after the voicemail is processed:

2016-07-01 04:48:02.930006 [DEBUG] mod_lua.cpp:459 lua event hook: execute 'voicemail-event.lua'

Check the device the SMS was sent to and you'll see a message like the following:

Voicemail from Extension 1000 (1000) at Fri 04:48 length 6 seconds to box 1001.