Asterisk Gateway Interface 1.4 and 1.6 Programming Table of Contents

Table of Contents

• Preface

• Chapter 1: Installing a 'Vanilla' Asterisk
• Downloading Asterisk
• Zaptel—Zapata Telephony Driver
• DAHDI—Digium Asterisk Hardware Device Interface
• Libpri—ISDN PRI Library
• Asterisk—the open source PBX
• Asterisk-addons—the open source PBX
• Asterisk—SVN source packages
• Obtaining the source code packages from SVN
• Compilation dependencies
• Compiling the source code
• Compiling and installing Zaptel
• Step 1: Configure
• Step 2: Define the options you would like to compile
• Step 3: Compiling and installing
• Compiling and installing DAHDI
• Step 1: Compile the kernel module
• Step 2: Install the dahdi kernel module
• Step 3: Compile the dahdi-tools package
• Step 4: Configure the dahdi-tools to be installed
• Step 5: Compile and install dahdi-tools
• Differences between Zaptel and DAHDI
• Compiling and installing libpri
• Compiling and installing Asterisk
• Step 1: Configure
• Step 2: Define the options you would like to compile
• Step 3: Compiling the code
• Summary

• Chapter 2: Basic IVR Development: Using the Asterisk DialPlan
• The dialplan is a set of "finite state machines"
• The dialplan syntax
• The extension
• Inclusion of contexts
• The [general] and [global] contexts
• Extension pattern matching
• Special extensions
• Dialplan Switches
• Variables, applications, and functions
• Variables—built-in and custom
• Applications and functions
• Your first IVR application
• Summary

• Chapter 3: More IVR Development: Input, Recordings, and Call Control
• Grabbing and processing user input
• The Read application
• Branching—Goto, GotoIf, Gosub, and GosubIf
• Goto and GotoIf
• Writing expressions
• Regular expressions
• Gosub and GosubIf
• Exec, ExecIf, and TryExec
• Macros—Macro and MacroExclusive
• Additional Asterisk applications
• Self exploration
• Summary

• Chapter 4: A Primer to AGI: Asterisk Gateway Interface
• How does AGI work?
• EAGI, DeadAGI and FastAGI
• EAGI—Enhanced Asterisk Gateway Interface
• DeadAGI—execution on hangup
• FastAGI—AGI execution via a TCP socket
• AGI scripting frameworks
• The AGI application
• The AGI execution flow
• The AGI methods API
• The ten rules of AGI development
• Rule #1: An AGI script should terminate as fast as possible
• Rule #2: Blocking applications have no place in AGI
• Rule #3: Asterisk channels are stateful—use them
• Rule #4: AGI scripts should manipulate data—no more
• Rule #5: VM based languages are bad for AGI scripting
• Rule #6: Binary-compiled AGI is not always the answer
• Rule #7: Balance your scripts with dialplan logic
• Rule #8: Balance your scripts with web services
• Rule #9: Syslog is your friend—use it
• Rule #10: The Internet is for Asterisk
• A preface to what's coming ahead
• Summary

• Chapter 5: AGI Scripting with PHP
• PHP-CLI vs. PHP-CGI
• The php.ini configuration file
• AGI script permissions
• The structure of a PHP based AGI script
• Communication between Asterisk and AGI
• The AGI Hello-World program
• AGI debugging
• Summary

• Chapter 6: PHPAGI: An AGI Class Library in PHP
• Obtaining PHPAGI
• The file structure of PHPAGI
• A very simple PHPAGI example
• The AGI/Dialplan high-wire act
• Introducing Atomic-AGI
• Atomic-AGI—a dialplan example
• SetSessionID.agi—meet your state maintainer
• agiWrapper.agi—an all purpose AGI execution wrapper
• A slightly more complex PHPAGI example
• db_validate_target.inc.php
• db_register_cdr.inc.php
• AGI Scripts in popular Asterisk applications
• FreePBX™—the most popular Asterisk management GUI
• A2Billing™—a pre-paid calling card system
• Summary

• Chapter 7: FastAGI: AGI as a TCP Server
• FastAGI argument handling
• Asterisk 1.2.X and 1.4.X
• Asterisk 1.6.X
• FastAGI error handling
• Asterisk 1.2.X
• Asterisk 1.4.X and 1.6.X
• FastAGI with PHPAGI and xinetd
• Introducing xintetd—the Internet services daemon
• Configuring xinetd for FastAGI and PHPAGI
• Configuring PHPAGI for FastAGI
• The fastagiWrapper.php bootstrap
• Performance consideration
• FastAGI with PHPAGI and Google
• FastAGI with other tool kits
• Asterisk::FastAGI—a PERL module for FastAGI handling
• Asterisk-JAVA—a Java package for Asterisk
• Summary

• Chapter 8: AMI: The Asterisk Manager Interface
• AMI—the history
• How does AMI work?
• AMI with Asterisk 1.0 and 1.2
• AMI with Asterisk 1.4 and 1.6
• AMI–understanding basics
• Events and Actions
• Logging in to the Manager Interface
• Sending actions to the Manager Interface
• Logging off from the Manager Interface
• PHPAGI and the AMI Interface
• Direct AMI interface invocation
• AMI interface invocation via the PHPAGI class
• Interacting with the AMI interface
• Sending actions to the AMI inteface
• Event callbacks from AMI interface
• PHPAGI AMI originate quirk
• Click-2-Call and Web-Callback
• Demystifying the Asterisk Originate manager action
• Welcome to Jabka—the world's favourite Click-2-Call
• AMI proxy servers
• AJAM—AJAX Enabled Manager
• Summary

• Chapter 9: Final Programming Project
• ACRG—Asterisk Call Recording Gateway
• Requirements
• Network connectivity—PSTN
• Project implementation guide
• Step 1: Analysis of the requirements
• Step 2: Understanding operational constraints
• Step 3: Detailed call flow charts
• Step 4: The Asterisk dialplan context
• Step 5: Develop your human interfaces
• Step 6: Test, test, and test again
• Additional programming projects
• Click-2-Call
• Jajah.Com
• Stateful call masking
• Punk'ed call
• Date rescue call
• Conference bridge
• Summary

• Chapter 10: Scaling Asterisk Applications
• Scaling Asterisk platforms
• Database query caching
• Starting up
• Using it in a script
• Utilization of web services
• Introduction to XML-RPC
• Apache versus Lighttpd
• Virtualization and cloud computing
• Summary

• Index