Book Image

FreeSWITCH 1.2 - Second Edition

Book Image

FreeSWITCH 1.2 - Second Edition

Overview of this book

FreeSWITCH is an open source telephony platform designed to facilitate the creation of voice and chat-driven products, scaling from a soft-phone to a PBX and even up to an enterprise-class soft-switch. It is always exciting to design and build your own telephony system to suit your needs, but the task is time-consuming and involves a lot of technical skill."FreeSWITCH 1.2" comes to your rescue to help you set up a telephony system quickly and securely using FreeSWITCH. It is rich with practical examples and will give you all of the information and skills needed to implement your own PBX system.You will start with a detailed description of the FreeSWITCH system architecture. Thereafter you will receive step-by-step instructions on how to set up basic and advanced features for your telephony platform.The book begins by introducing the architecture and workings of FreeSWITCH before detailing how to plan a telephone system and then moves on to the installation, configuration, and management of a feature-packed PBX. You will learn about maintaining a user directory, XML dial plan, and advanced dial plan concepts, call routing, and the extremely powerful Event Socket. You will finally learn about the online community and history of FreeSWITCH."FreeSWITCH 1.2" is an indispensable tool for novice and expert alike.
Table of Contents (24 chapters)
FreeSWITCH 1.2
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Using ESL to execute commands


In our previous examples we've originated calls from fs_cli. In this section we'll show you a couple of code samples that will do the same things from your favorite scripting language. For our examples, we're going to use Lua, since you've probably become accustomed to it by now. The ESL API is the same whether you use Python, Lua, PHP, Perl, or whatever, so the adventurous minds could follow along in their own favorite language.

Tip

ESL scripts versus built-in languages

Keep in mind that ESL-based programs are not the same as using built-in languages. The FreeSWITCH event socket is a TCP-based connection to FreeSWITCH. The ESL is an abstraction library that is available for more languages than just the few that are built-in to FreeSWITCH. You must first install the Lua, Perl, Python, or PHP for your system before using ESL. For Lua see http://www.lua.org for more information.

First, since the ESL modules aren't built as part of the default install, we'll need to...