asterisk users - Apr 2006 - Development news :: New AEL and configuration system

Friends in the Asterisk community,

Yesterday the Asterisk development branch, also known as "svn trunk",
changed quite a lot. We added
two major features: A new version of AEL and a new configuration  
system. Hang on, and I'll explain!

* AEL - The Asterisk Extension Language
--------------------------------------------------------

Last summer, Mark Spencer created a new language for creating your  
Asterisk dial plan. Before that,
many developers tried making the current dial plan "language" into a  
script language by adding
if/then/else and do/while constructs - and it all seemed very strange  
and, well, not really like a
script language.

So Mark decided to take another route and implemented a new language,  
that was interpreted
into the old. You could suddenly create a dial plan in a language  
that looked more like C,
and let the AEL parser create a dial plan based on the old language.  
This first version was
experimental and had a lot of problems. Writing a language parser is  
not an easy task.

Remember that what you write in the AEL file and what you see when  
you do "show dialplan"
in the CLI is very different. AEL is still interpreted into the old  
dial plan language.

The new AEL is implemented using Bison, which leads to a much more  
robust parser.
Steve Murphy has put a lot of work into implementing AEL2 and it  
looks very good. So good,
so Kevin removed the "experimental" flag on AEL, making it a standard
feature in Asterisk.



* AUTOCONF and MENUSELECT - Installation now is easier!
------------------------------------------------------------------------ 
------------

Since I joined the Asterisk community, I have seen regular requests  
for a "./configure"
script for Asterisk. The Asterisk Makefile replaced some of the  
functionality of the
"./configure" script, trying to find out what functionality was  
available on the host system.

Yesterday, we finally got an auto-configuration system. The Makefile  
now creates
a configure script, runs it to check what you have - MySQL, OSP,  
PostgreSQL,
CURL etc - and make sure the optimal Asterisk is created on your system.
Additionally, you can run "make menuselect" to be able to select what
modules
you want. No app_dial.so? Just disable it! Menuselect also marks  
clearly modules
that can't be installed on your system due to lacking third party  
libraries.

And to top it off, we now have ASCII art embedded into Asterisk!

* Making life easier for the Asterisk administrator
------------------------------------------------------------------
While these additions does not really change the functionality of  
your favourite
PBX, they make installation and configuration of your Asterisk system  
easier.
It's a big step forward and an important part of Asterisk 1.4.

Now, I have to learn the inner workings of this and adopt my branches  
to it...
Always good to have something to do ;-)

Greetings from the Asterisk Developer Community!

/Olle

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* Olle E. Johansson - oej@edvina.net
* Asterisk European tour - REGISTER NOW - http://www.meetasterisk.com