Navigation Framework using CF Architecture for a Client-Server Application using the open standards of the web Kedar Desai presented by

Navigation…a new paradigm  Queue based function control  Non URL based navigation

What is Navigation?  User’s perspective: –Ability to use the system in the most efficient manner  Designer’s perspective: –Ability to manage or direct the course of the user using the system

What is this“Client Server” Application?  MDI Interface  Thick Client  EXE  Built using PowerBuilder, Visual Basic, etc.

Associated Problems  Maintaining a code base  DLL Hell  Distributing an EXE  Maintaining ‘Help’ files  Difficulties in adding new functionality

About the Application  Justice Information System  Application Architecture Sybase Database ColdFusion Application Server Client Browser: HTML, JS, CSS

Application Challenges  Consists of around 500 Functions  Over 200 database tables  Database Intensive  Transaction Intensive

Application Frameworks  Two Main frameworks: –Navigation Framework Navigation Error Handler Business Rule Engine –Security Framework  Each framework is independent

What is so great about this Navigation framework?  Look and feel of a standard windows application  Excellent navigation  Uses ColdFusion

Navigation Framework: Features  Driven by keys.  Works on a queue architecture.  Maintains State in Session variables.

Message Module  Provides ability to maintain messages in the database  Functions include: –Message Search and List, Message Modify, Message Delete, Message New, Message Text Modify, Message Details

Demo

Function Architecture  Five ‘.cfm’ files per function  Five hidden fields per function

The Five ‘.cfm’ files  Form Page –Main cfm file –OnError cfm file –CFForm cfm file –Presentation cfm file  Action Page –Action cfm file

The Hidden Fields  Each function has five hidden fields –Function id –Page id –Main cfm file name –OnError cfm file name –Action cfm file name –Target Function id

Navigation Controllers  Form Controller –Opens the function  Action Controller –Triggers the action of the function  OnError Controller –Controls display of errors  Key Controller –Controls ‘key’ and ‘queue’ maintenance

What are keys?  Every function has a set of input and/or output keys  A key is a value that fetches data to be displayed on the function  Keys are kept in a queue  If no keys exists, the default function is opened

What is a queue?  Maintains information about the activities that the user wants to perform in a sequence.  Function queue and keys queue are the major queues.

How is state maintained?  Using Session variables  Each session has a ‘userid’ associated with it, thus enabling multiple sessions on the client browser.

How does a function open?  Form Controller controls the opening of the form.  The file opening sequence is: –Main cfm –OnError cfm –CFForm cfm –Presentation cfm

Navigation Flow Function List Action Controller Errors? Error Controller Form Controller Function Displayed On Browser Yes No

Error Controller  Builds the error page  Appends the error page to the form page

Features  Secure Access.  Centralized action and form pages.  Centralized error handling.  Everything is a custom tag.  Logic and presentation isolated.  F5 or Refresh works as in a browser.

Points to ponder  Browser back and forward buttons unusable.  Even though everything is a custom tag, ‘Custom Tag’ directory is not helpful  Not much use for Application.cfm

Productivity Metrics  Built in under 3 months  A function being developed every two days  A TEAM of five