CGI Programming Using Perl - PRL480

This course bridges the gap between using HTML to create static Web pages and using Perl CGI scripts to create dynamic Web pages. The course emphasizes using the Perl 5 CGI library routines to process HTML forms by providing extensive working examples and by students writing applications to illustrate the concepts presented. This course is not intended to be a substitute for a Perl programming course.
Course ID: PRL480

Duration: 3 days

Audience: Web site developers wanting to create interactive Web pages.

Prerequisites: Familiarity with HTML forms. Programming experience is required. Basic UNIX skills and the ability to use vi or a basic text editor are also required.
Topics:

The Internet and the Web

• TCP/IP and Ports
• DNS vs. Hosts Files
• Servers and Clients
• Client/Server Protocols

Browsers and Servers

• URLs
• WEB Browsers and Servers
• The Hypertext Transfer Protocol
• HTTP Requests and Responses
• HTTP Headers
• HTTP Requests
• Mime Types

Introduction to CGI

• HTML Tag Stucture
• HTML Document Structure
• URLs and CGI
• CGI Programs
• Running and Debugging from the Command Line
• Running and Debugging from a Browser
• Handling an HTML Form with CGI
• Generating HTML

CGI and Perl

• Perl
• Perl Programs
• Why Use CGI.pm (and Where is It?)
• Running and Debugging from the Command Line
• Generating HTML with CGI.pm
• Running and Debugging from a Browser

Generating HTML

• Introduction to CGI.pm
• How to use CGI.pm Online Documentation
• CGI.pm Rules for General HTML Tags
• CGI.pm Rules for HTML Form Tags
• Named vs. Positional Parameters in CGI.pm

Generating Forms

• General Structure of HTML Forms
• Form Element Tags
• Pushbuttons
• Radiobuttons
• Checkboxes
• Popups and Listboxes
• Textfields, Passwords, and Textareas

CGI Data Flow Architecture

• URL Encoding and Decoding
• Data Flow Between Browsers and Servers
• GET vs. POST
• Which to Use?
• CGI Environment Variables
• Accessing CGI Environment Variables

Processing Form Data

• Static Forms
• Dynamic Forms
• Controlling Flow with User Input
• Accessing Form Data Using CGI.pm
• The param Method of CGI.pm
• Sticky Widgets
• Validating Input from the Browser
• Command Line Debugging

Client-Side Statefulness

• Stateful vs Stateless
• Why use Stateful CGI Applications?
• Program to Program Interaction
• Stateful Access with Hidden Fields
• Multiple Forms and Hidden Fields
• Stateful Access with Netscape Cookies
• Using Cookies with CGI.pm
• Cookie Management

Database Access

• Server-Side Statefulness
• Flat-File Databases
• Structuring Text Data
• File Permissions and Flat-File Databases
• Perl DBM Interface
• Perl DBI/DBD Interface
• Issues With Statefulness

Additional Web Programming Features

• Extra Path Information
• Frames
• Server Side Includes (SSI)
• The exec command
• A Page Hit Counter Using SSI
• Animation Description
• Netscape Server Push
• Client Pull
• The GD.pm Module

CGI Security Issues

• Browser to Server Security Issues
• CGI Security Issues
• CGI Interaction with the Operating System
• Database / File System Overflow
• CGI and User Authentication

Appendix 1 - Overview of Perl

• What is Perl?
• Running Perl Programs
• Sample Program
• Another Sample Program
• Yet Another Example

Appendix 2 - Perl Variables

• Three Types of Variables
• Variable Names and Syntax
• Variable Naming
• Lists
• Scalar and List Contexts
• Hashes
• Hash Functions

Appendix 3 - Flow Control

• Simple Statements
• Simple Statement Modifiers
• Compound Statements
• The next, last, and redo Statements
• The for Loop
• The foreach Loop