If you have a Macintosh computer, you may have wondered if there is any way to have a pop-up notification of who is calling whenever your extension rings. It turns out that there is, but it's not exactly straightforward. This method may also work for certain systems running under Windows or Linux, although the client you use will be different. I will explain how I set it up on a Mac. There is one caveat, if your computer does not have a fixed IP address on your local network, then you'll have to make a file edit in the FreePBX configuration every time it changes. There may be a way around that, but I haven't found it yet.
I do not consider the following an elegant solution, indeed there are parts of it I consider a hack. But it works. To begin with, look over the page at http://mezzo.net/asterisk/app_notify.html - we are going to install the "Notify application module for the Asterisk PBX" at the top of the page, and then the appropriate client for your computer (lower on the page). Of course, the Notify application module must be installed on the system running Asterisk and FreePBX. So start there at the command prompt and do this:
cd /usr/src
Asterisk 1.2.x: wget http://mezzo.net/asterisk/app_notify-1.0.tgz
or
Asterisk 1.4.x: wget http://mezzo.net/asterisk/app_notify-2.0rc1.tgz
(These are just examples, you should probably use whichever download is the most recent for your version of Asterisk)
tar -xzf app_notify-1.0.tgz (replace filename with whatever you actually downloaded)
cd app_notify-1.0 (ditto, omitting the .tgz extension)
make install
Restart Asterisk or load the application module with:
load app_notify.so
(I went to the Asterisk CLI and did a restart when convenient just to make sure I wouldn't interrupt any calls)
That's all you have to do to install the module. While at the Linux command prompt, bring up your text editor of choice (nano, Midnight Commander's editor, or whatever you like) and edit etc/asterisk/extensions_custom.conf and, somewhere under the [from-internal-custom] context insert these two lines for each extension for which you wish to generate notification messages (this example assumes you want to monitor extension 525 and send the notifications to the computer at local IP address 192.168.0.123):
exten => ****525,1,Notify(${CALLERID(num)}|${CALLERID(name)}|525/192.168.0.123)
exten => ****525,n,Busy
Change the boldfaced items to the proper extension number and/or IP address of the computer to receive the notifications.
If you want notifications for more than one extension, repeat the above two lines for each extension you want to monitor. If you want the notifications to go to more than one computer, just duplicate the topmost line as many times as you need to, changing only the target IP address (so it will send the notification to one computer, then the next, and so on). Note that you're actually creating a custom extension consisting of "****" + the extension number - you can change this to something else but it must be unique in your system. My goal was to make it something that no one would actually dial, since it's only used internally. When you're through with your edits, don't forget to save the changes!
Now it's time to use your web browser and browse to the FreePBX configuration. What you need to do is create a Follow-Me for the extensions you want to monitor. So make sure that FreePBX's Follow-me module is installed, then go there and select the follow-me for the extension you wish to monitor (again we're using 525 in this example). Add the Follow-Me, make the ring strategy firstnotonphone, set the ring time to whatever you want, and make the Destination if no answer whatever you want (probably the extensions's voicemail). In the Follow-Me List put two entries. At the top put the custom extension number with the four asterisks in front of the number, and (this is very important) a pound sign (hash mark for you Brits) on the end. On the next line, just put the extension number itself. So for extension 525, you'd have these two entries:
****525#
525
Save this. Note that if you already have a Follow-me for the extension, it might complicate things a little bit, or maybe not. The basic idea is to attempt a call to the custom extension (which will always fail busy) just before you attempt the real extension. If you already have a certain configuration of Follow-me set up, it might be necessary to move some or all of the Follow-me settings to a Ring Group to make this work, and use the Ring Group as the destination of the Follow-me, but that's beyond the scope of this article (I only mention that because using a Ring Group as the destination of the Follow-me may help resolve some logical conflicts, and you can even chain ring groups if necessary. Most users won't have this issue, but I mention the possibility for those who do).
The one flaw in this is that you'll receive the popup notification even if you are currently on the phone, and the call ultimately goes to a different extension or to voicemail. For some situations that would be desirable behavior, whereas in others it would not. Personally I want the notifications of calls I missed, but maybe you don't. I did say this was a hack, right?!
Once you have this set up, and reload the configuration in FreePBX, the notifications will be sent out (if you have done everything correctly) One note, on the module download page, it shows specifying the target computer by name, not IP address. That trick only works if the computer name actually resolves to something, which means you'd have to have a line in /etc/hosts linking the computer name and IP address, or you'd have to have a local DNS server that resolves local machine names. Most home and small business users won't have either. So the best plan is, give the computer a fixed IP address (most routers provide a way to do this), then just specify that IP address in extensions_custom.conf.
Installing the client
Go back to http://mezzo.net/asterisk/app_notify.html and pick up the appropriate client for the target computer (that receives the notifications). I have only installed this on a Mac (OS X Leopard) so here are a few hints for that client:
I was not able to make the dialer function work - don't know why and don't really care because that wasn't my goal in the first place. So that will not be covered here (if you get it to work, please leave a comment and I may revise this).
To receive notifications you install the client (standard software install method), then go to System Preferences | Other | Asterisk (yes, the client is called "Asterisk" in the preference panel). Under "Notifier" I suggest you turn on Growl notifications if you have Growl installed, and turn off "Speak announcement" - although that would be a cool feature if it worked reliably, it appears that it only works once or twice and then you don't get ANY notifications at all until you turn "Speak announcement" back off (and usually you have to stop and restart the client as well).
There also currently a bug where you enter the server address. Unless you have Bonjour installed on your Asterisk server (something also offered at this site, but good luck in getting it set up and working if you're not a true Linux geek - and if you are and you make it work, please leave a comment and give us step by step instructions!), you will have to enter the IP address manually. But the keyboard input routine is buggy! So go to another application (text editor, e-mail program, whatever) and type in your Asterisk server address, then highlight and copy it (Option-C) so it's in your clipboard. Go back to the preferences panel, click the plus (+) to add a server, then click in the location where the server address should be, and then a text box should appear which SHOULD allow you to enter the address. Click in it and paste the server address (Option-V) from the clipboard. If you still get extraneous characters, highlight all the characters other than the correct ones using the mouse, then right-click and select "cut", and you should be left with the correct server address. Yes, I know that's a screwy way to do it, but whatever works...
Once the client is configured you may need to instruct the computer's firewall to allow it to receive the incoming notifications. The listen port defaults to 40000 (I don't advise trying to change that unless there's a serious conflict). As soon as I configured the client, I got a popup asking if I wanted to allow incoming communications to that program, to which I answered in the affirmative, and that's all there was to it.
I do wish there were a better way to insert some custom code into the FreePBX generated dial plan, that would fire off a custom dialplan fragment just prior to ringing an extension. That would not only be useful for this application, but probably for several others where you might want to do something special just before an extension rings. I'm aware that you can modify the dialplan if you create a module; p_lindheimer (one of the developers) said, "...you can splice a line in to the dialplan. Take a look at pinset module, you will see how it splices a call to it's own macro in the outbound route macros, or I think cidlookup does the same into ext-did. It would require writing a simple module to do what you want but that is not really all that hard." Well, it might not be hard for some people, but it would be impossible for me (I have only a VERY limited knowledge of Perl, none at all of PHP, and don't have a clue how a module is constructed - I know you can view module code easily but unless I'm told exactly what I'm looking at, it usually makes no sense at all to me). My point is, if you have the knowledge that I lack, there are much better ways to accomplish this, but until someone creates a module (or ANYTHING better than what I've described), the above is the only way I know how to do it, particularly with the client on a Mac computer.