Call forwarding in Auerswald PBX (lua)

Example: LUA Template Call forwarding in Auerswald PBX

call_fwd_in_pbx.xml

<?xml version="1.0" encoding="UTF-8"?>
<templates>
  <!-- switch the call forwarding for not responding within the PBX on or off
    parameter: identity
    parameter: target: call forwarding target
  -->
  <template name="@string/call_forwarding_no_response_title">
    <keyConfiguration>
      <lua>
        <code>
	  local valid = false
          local active = false
          local on = "*61*"
          local off = "#61#"
          local userpath = "/identities/identity["..identity.."]/"
          local host = config.get(userpath .. "host")
          local user = config.get(userpath .. "username")
 
          local function updateLed()
            if valid then
              if active then
                key:setLed( "green" )
              else
                key:setLed( "off" )
              end
            else
              key:setLed( "red", true )
            end
          end
 
          local unescape = function(url)
            return url:gsub("%%(%x%x)", function(x) return string.char(tonumber(x, 16)) end )
          end
 
          local function check_sub(data, uri, handle)
            local x = xml.eval(data)
            local test_uri_on = "sip:"..on..target.."#"..user.."@"..host
            if unescape(uri) == test_uri_on and x ~= nil then
              for _,dlg in ipairs(x) do
                state = dlg:find("state") 
                if state and state[1] == "trying" then 
                  active = true
                elseif state and state[1] == "terminated" then
                  active = false
                end
              end
            end
            updateLed()
          end
 
          local function check_valid()
            if identity =="" or target=="" then
              valid = false
            else
              valid = true
            end
          end
 
          local function sub()
            sip.subscribe(on..target.."#"..user,"0",identity,check_sub)
          end
 
          function onKeyUp()
            if active and valid then
              sip.invite(off.."#"..user)
            elseif valid then
              sip.invite(on..target.."#"..user)
            end
          end
 
          check_valid()
          updateLed()
          sub()
          </code>
          <params>
            <!-- These parameters are available by name within the lua-script (code-section).
                 Their value is passed from the parameters-section (see below) -->
            <param name="identity"/>
            <param name="target"/>
          </params>
        </lua>
      </keyConfiguration>
      <parameters>
        <!-- entered by user in phone-UI or on website when configuring this key-function.
             Will then be passed as value to the lua-scripts params-section. -->
        <parameter name="@string/identity">         
	  <path>//param[@name="identity"]/value</path>
        </parameter>
        <parameter name="@string/target">
          <path>//param[@name="target"]/value</path>
        </parameter>
      </parameters>
  </template>
</templates>