N-tier ColdFusion Development with CFC

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N-tier ColdFusion Development with CFCs

• Neil Ross, MCP
• neil_at_codesweeper.com
• www.codesweeper.com
• www.insidecoldfusionmx.com

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Introduction

• Neil Ross
• Co-Author of Inside ColdFusion MX
• Certified ColdFusion Developer
• Certified ColdFusion Instructor
• Presenter at DevCon 2000 in DC
• Founder and Manager of Central Pennsylvania
  ColdFusion User Group
• Former member of Allaire Consulting Services

3
Overview

• Understanding the Main Concepts
• N-tier Applications
• CFCs
• N-tier Architecture
• Using CFCs
• Examining a Sample Application
• Discussion

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The Main Concepts

• N-tier Architecture
• Logical Structure
• Division of the App on a conceptual level
• Physical Structure
• Directory Structure
• Server Clustering

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The Main Concepts (contd)

• CFCs
• What are CFCs?
• Based on Object Oriented Concepts
• Leverage the Strengths of OO Programming
• When do you use CFCs?
• Business Logic
• Data Access

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N-tier Architecture

• Logical Structure
• Presentation - UI
• Process Business Logic / Validation
• Data RDBMS / Stored Procs / Queries
• Physical Structure
• Form meets Function / CFC Packaging
• Directory Structure
• Server Environment

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CFCs

• What are CFCs?
• CFC ColdFusion Components
• CFCs are ColdFusion files, with one notable
  exception they must have an extension of CFC
• Reusable ColdFusion based objects that facilitate
  code encapsulation and reuse

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CFCs (contd)

• Use CFCs when you need to
• Separate content or data from presentation code
• Write business logic and data calls that are
  accessible by multiple front-end
• Check for required parameters or validate
  parameter data types

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CFCs (contd)

• CFC Terminology
• Methods equate to CFFUNCTION tags, which
  encapsulate individual functions or uses for the
  code within them
• Arguments are parameters that are passed into the
  CFC
• Return Values are the values passed out of a
  processed method

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CFCs (contd)

• Writing CFCs
• CFCOMPONENT

ltcfcomponentgt ltcffunction name"authenticate"
access"public" output"false"gt ltcfargument
name"user" type"string" required"true"/gt
ltcfargument name"passwd" type"string"
required"true"/gt ltcfquery
name"checkAuthentication" datasource"SecurityDB"
gt SELECT username FROM
Security WHERE username
arguments.user AND password
arguments.passwd lt/cfquerygt ltcfif
checkAuthentication.recordCountgt ltcfreturn
checkAuthentication.user/gt ltcfelsegt
ltcfreturn false/gt lt/cfifgt
lt/cffunctiongt lt/cfcomponentgt
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Invoking CFCs

• Using CFINVOKE
• CFOBJECT or CFSCRIPT

ltcfinvoke component"hogs_app._components.tally"
method"get_user_tallies" userid"url.uid"
returnvariable"getUserTallies"gt lt/cfinvokegt
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CFCs (contd)

• CFC Packaging
• Package by Process
• Refers to more than just saving them in the same
  directory
• Package name from Custom Tag directory or webroot
• By being aware of CFC packaging, you can invoke
  package-accessible methods within another CFC
  in the package

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Examining a Sample Application

• HogTallied Example
• Security
• Tallies
• Games
• Predictions

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Discussion