Perl Programming and CGI Scripting

Perl Programming and CGI Scripting Course Overview:

Introduction to Perl

• Origin and Design Goals of Perl
• Overview of Perl Features
• Getting and Installing Perl
• Accessing Documentation via perldoc
• HTML-Format Reference Documentation
• Perl Strengths and Limitations

Getting Started With Perl

• Explicit Invocation of the Perl Interpreter
  • Running Perl on UNIX vs. Windows
  • Running Perl from the Command Line
  • Using Command Line Options
  • Using Debug Mode
• Implicit Invocation of the Perl Interpreter
• Running and Debugging Perl Scripts
• Simple and Compound Statements
• Fundamental Input Techniques
• Using the print Function to Generate Standard Output

Using Variables

• Scalar Variables
• Introduction to Standard Data Types
• Retrieving Standard Input Using the Default Variable $_
• Reserved Scalar Variables
• Assigning Strings and Numbers to Scalar Variables
• Declaring Constants for Persistent Values
• Using strict to Declare Variables

Pattern Matching in Perl

• Regular Expressions in Perl
• Using Pattern Matching Operators
• Altering Data with Substitutions in Regular Expressions
• Using Backreferences to Capture Data from Regular Expression Matching
• Global and Case-Insensitive Matches
• Altering Data with Character Translation
• Using Variables in Patterns

Operators

• Introduction to Fundamental Operators
• Operator Precedence and Associativity
• Using the Ternary Operator ?: as a Shortcut for the if Statement
• Using <FILEHANDLE> and <> File I/ O Operators for Standard Input/ Output
• Using the Shortcut Operators =, -=, *=, /=

String Manipulation

• String Comparison
• String Relations
• Concatenation
• Substring Manipulation
• Using chomp and chop to Eliminate EOL Characters
• Escape Characters for Formatting
• String Manipulation Functions

Flow Control: Conditional Statements and Looping

• Conditional Expressions and Logical Operators
• if/ else/ elsif and unless
• Constructing switch/ case Equivalent Expressions
• while Loops and do Loops
• for and foreach Loops
• Labels
• Altering Program Flow with next, last, and redo
• Trapping Errors with the eval Function
• Terminating a Script with exit

Subroutines and Parameters

• Simplifying Scripts with Subroutines
• Defining and Calling a Subroutine
• Passing Arguments by Value
• Passing Arguments by Reference
• Using return to Return a Value
• Controlling Variable Scope using my and local Keywords

Arrays and Hashes

• Defining Numeric Index Arrays
• Defining Associative Arrays
• Sorting Arrays with the sort Function
• Adding and Deleting Items Using push, pop, shift, and unshift
• Using slice, splice, and reverse
• Other Array Manipulation Techniques
• Looping through an Array
• Merging Arrays
• Associative Array Manipulation Functions
• Introduction to Hashes
• Preallocating Memory to Optimize Hash Performance

Packages and Modules

• The Power of Packages and Modules
• Introduction to Standard Modules
• Where to Find Modules on the Internet
• Installing a Module on UNIX or Windows
• Creating Packages for Portability
• Using Packages to Create Isolated Namespaces and to Separate Code
• Creating Modules
• Creating and Using Symbols in a Module
• Using the Exporter to Export Symbols from a Perl Module

File and Directory I/ O

• Using open and close
• File Open Modes
• Reading Files into Arrays
• Retrieving File Metadata
• Built-in File Management Functions
• Using print and write
• File Test Operators
• Directory Manipulation Using opendir, closedir, readdir, chdir, mkdir and rmdir

Input/ Output Processing

• Parsing Input
• Using Standard Input, Standard Output, and Standard Error
• String and Field Processing
• Using Streams and Pipes
• Using die to Quit with an Error
• Redirecting Standard Output and Standard Error to a File
• Getting Standard Input from a File

Implementing Command Line Arguments

• Reading Command Line Arguments from ARGV
• Read Files Explicitly with <ARGV> and Implicitly with <>
• Manipulating Positional Parameters with push, pop, shift
• Process Lists of Files
• Processing Command Line Options with getopt or getopts
• Analyzing Command Line Argument Values with the Getopt::Std and Getopt::Long Modules
• Reserved Variables
• Manipulating Identifiable Options Using GetOptions

Perl Report Formatting

• Defining Report Formats
• Justifying Text (Left, Right, Center)
• Using write to Generate Reports
• Defining here Documents for Report Customization
• Creating Report Headers
• Using Built-in Variables to Control Report Appearance
• Printing Line Numbers on a Report
• Formatting Multi-Line Output
• Writing Formatted Text to a File

Debugging In Perl

• Using the Built-in Perl Debugger
• Starting the Debugger
• Debugger Command Syntax
• Checking for Script Syntax Errors
• Solving Compile-Time Errors
• Single-Stepping through a Script
• Executing to Breakpoints
• Setting Global Watches
• Printing Values of Variables
• Listing All Variables Used in the Script
• Using Strict Error Checking
• Quitting the Debugger

References

• Life Cycle of a Reference
• Hard References and Anonymous References
• Use of References to Create Complex Data Structures
• Creating Hard and Anonymous References
• Modifying References
• Dereferencing a Reference
• The Arrow Operator ->
• Building Complex Data Structures with Multi-Dimensional Arrays and Hashes

Accessing a Database Using Perl DBI

• Database Access Life Cycle
• Using DBI and DBD to Connect to a Database
• Fundamental Data Storage and Retrieval Strategies
• DBI Query Syntax
• Using DBI Methods to Retrieve Database Information
  • Preparing Queries to be Executed
  • Creating Parameterized Queries
  • Executing Queries Using execute and do
• Fetching the Result Set to Achieve Workable Data in the Perl Script
  • Extracting Data Using an Array
  • Extracting Data Using a Hash
• Useful Utilities to Aid in Database Development
• Using Other Modules to Access Databases on the Web
• Extracting Data Using a Hash
• Displaying Results from Queries in a Report
• Releasing Database Resources

Perl Object Oriented Programming

• Object Oriented Programming Concepts
• Object Oriented Programming Terminology
• How Perl Implements Object Oriented Programming
• Modeling Software Objects Using Classes and Base Classes
• Creating Classes, Objects, Methods and Attributes
• Writing Constructors to Initialize of Objects
• Using bless to Turn References into Objects
• Creating Class Hierarchies through Inheritance

Web Architecture and CGI Scripting Overview

• Static vs. Dynamic Web Pages
  • Serving a Static HTML Web Page
  • Serving a Dynamic HTML Web Page
  • Dynamic Web Page Capabilities
• The Common Gateway Interface
  • How Server-Side CGI Scripts Work
• Differences between Client-Side and Server-Side Script Environment
• Strengths and Weaknesses of Web Programming Languages

CGI Scripting with Perl

• Perl's Role in Distributed Web Applications
• Using Environment Variables to Control CGI Scripts
• Communicating with the Web Server
• Perl CGI Script Instantiation and Invocation
• Generating Output for the Browser
• CGI Security Mechanisms

Configuring a Web Server for CGI

• Servers and CGI
• The Apache httpd. conf File
• Aliasing Standard Directories in Apache
• Using Standard Apache-Aliased Directories
• The Default Apache cgi-bin Directory
• Aliasing CGI-Enabled Directories in Apache

Fundamentals of CGI Scripting with Perl

• Perl's Role in Distributed Web Applications
• Using Environment Variables to Control CGI Scripts
• Communicating with the Web Server
• Perl CGI Script Instantiation and Invocation
• Generating Output for the Browser
• CGI Security Mechanisms
• The Importance of the "Shebang" Line
• "Shebang" Line CGI Errors
• Debugging CGI Errors
• Linux vs. Windows File Format Errors
• Setting Linux File Protections
• Specifying the Page MIME Type
• Generating Standards-Compliant HTML

Generating Dynamic Web Pages Using Perl/ CGI

• Generating Dynamic Web Pages and Dynamic Content
• The Role of JavaScript
• Generating JavaScript Using CGI
• Displaying Data in Tables
  • Using Environment Variables to Control CGI Scripts
• Displaying Data from Files
• CGI Output Stream Buffering

Dynamic Behavior Based on Query Strings

• The Query String Part of a URL
• Parsing the Query String
• Using Query Strings to Maintain Session State
• User-Defined Modules and CGI

Processing HTML Forms with Perl CGI

• Creating and Submitting HTML Forms
• HTML Input Elements
• Submitting a Form
• Form Interaction Summary
• Populating Form Elements Using CGI
• Processing HTML Forms
  • Characteristics of the GET Method
  • GET Method Environment Variables
  • Characteristics of the POST Method
  • POST Method Environment Variables
• Using Form Data Validation to Check Data Values

Using the Perl CGI. pm Module - Introduction

• Orientation to CGI. pm
• The Power of Perl-Supplied Routines
• Simplifying Debugging
• Using CGI. pm in Object-Oriented Style
• Named Parameter Syntax
• Using CGI. pm in Procedural Style
• Importing Groups of CGI. pm Methods
• CGI. pm Output and XHTML
• Mixing CGI. pm Methods with Standard Perl
• Custom Tag Generation

Form Processing with CGI. pm

• Classes of CGI. pm Methods
• Specifying Arguments for HTML Tags
• Differentiating Blank & Missing Parameters
• Using Passed Parameters as Numbers

Maintaining State with CGI. pm

• State Information and the Web
• Using Extra Path Information
• Using Hidden Fields in Forms
• Using Client-Side Cookies
• Setting Cookies
• Cookie Parameters
• Setting Cookies from Form Data
• Deleting Cookies
• Form Validation and Cookie Storage
• Cookie Deletion
• Overcoming Cookie Limitations

Performance Optimization Using ModPerl

• Overview of Apache Web Server Functionality
• Comparing the Speed of CGI Scripting vs. ModPerl
• Configuring Apache with Perl and ModPerl
• Apache Strengths and Limitations
• Using the Apache::Registry Module
• Extending and Enhancing Apache Functionality

Developing Multi-Tiered Web Applications

• Review of Multi-Tiered Web Application Components
• Putting It All Together
• Using High-Level Packages to Assist with Scalability and Maintainability