ColdFusion Internals

© 2014 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential.

ColdFusion InternalsPaul Nibin K J


Introduction

2

Client

Web Server


Agenda

Life of a CFM request

Classloading in ColdFusion

How does RESTful web service work?

3

© 2014 Adobe Systems Incorporated. All Rights Reserved. Adobe Confidential. 4

Life of a request


Life of request in ColdFusion

5


Template Classloader

In filter chain

6

1. Request Validation

• Validates the request.

2. PathResolution

• Resolves absolute CFM Path

3.Application Resolution

• Locates Applicati-on.

• Creates Applicati-on scope.

• Invokes life cycle method

4. Parse

• Parse the CFM file .

• Generate AST using the grammar.

5.Bytecode Generation • Translat

e the AST to java byte code



You are part of request validation too.

7

You can configure the following validations through settings.

Request Size Limits

Request Limits


2. Path Resolution

8

/employee/addEmployee.cfm

C:\inetpub\wwwroot\employee\addEmployee.cfm

http://localhost/employee/addEmployee.cfm

Absolute

Path

Virtual Path

Request URL

Connector

You can cache the web server path using an admin setting.


3. Application Resolution

Finds the Application.cfc

9

Creates Application Scope

Invokes Life cycle methods

OnApplicationStart()

OnRequestStart()

OnError()



Finds the Application.cfc

10

Creates Application Scope

Invokes Life cycle methods

OnApplicationStart()

OnRequestStart()

OnError()

Start

Check for the

Application.cfc in

current directory.

Found

Application.cf

c?

Found Application

Check for the

Application.cfc in

parent directory.

Yes

No

Setting to specify till what level ColdFusion should search for Application.cfc


Unnamed applications

11

axis1Test

Application.cfc

<cfcomponent>

<cfset this.wssettings.version.publish=“1”>

</cfcomponent>

basic.cfc

axis2Test

Application.cfc

<cfcomponent>

<cfset this.wssettings.version.publish=“2”>

</cfcomponent>

basic.cfc

http://localhost/axis1Test/basic.cfc?wsdl

http://localhost/axis2Test/basic.cfc?wsdl

ColdFusion disables the creation of un named applications using an

admin setting.


4. Parsing

12

<cfscript>

function hello() {

writeOutput("hello");

}

hello();

</cfscript>Template

Reader

Abstract Syntax Tree (AST)


4. Parsing

13

<cfscript>

function hello() {

writeOutput("hello");

}

hello();

</cfscript>Template

Reader

Abstract Syntax Tree (AST)


Template Reader

Reads the CFM and creates a stream.

14

Encoding?


Automatic encoding identification

15

Start

Use

encoding

Guess

encoding

(icu4j)

Is guess

probability

100%?

Is BOM

present?

End

Yes

Yes

No

Use system

encoding

End

No

<cfprocessingdirective

..>

Save the file with

BOM

-Dfile.encoding=“”


5. Byte code generation

16

AST

Byte Code

Engineering Library

(BCEL)

Byte Code

<cfusion_Root>\wwwroot\WEB-

INF\cfclasses


Template Classloader

17

Start

Is

class

in

cache

?

Check Last

Modified Date of

CFM

Is

Modifie

d?

End

Parse

Generate

byte code

Load byte

code

Use cached Class

No

Yes

No

Yes

Clear template

cache

Enable trusted

cache


Summary

ColdFusion filter chain has 5 main phases

18


o Settings in administrator

2. Path Resolution

o Cache web server path setting


o Finding Application.cfc

o Unnamed applications

4. Parsing

o File encoding

5. Bytecode generation

o Template Classloader


Classloading


Class Loading

-Dcoldfusion.classPath = {application.home}/lib/updates, {application.home}/lib,{application.home}/lib/axis2,{application.home}/gateway/lib/,…

20

In jvm.config

ClassLoader

cfusion/libcfusion/lib/update

s

cfusion/lib/axis

2


Prior to CF10

Create a folder in cfusion\lib.

21

Cons

Conflicts

May hamper normal server functioning.

Any changes in jar files need server restart to take effect.

Copy your jars to the new folder.

Edit jvm.config to add the new folder to the end of coldfusion.classPath

property


CF10 and afterwards

CF10 introduced enhanced java integration.

Application setting available to specify custom classpath.

<cfset this.javaSettings = {LoadPaths = [".\java_lib\",".\java\myjar.jar"],

reloadOnChange = false}>

22

Pros

Complete isolation

Will not affect server functioning

Allows reloading


RESTful web services


RESTful web services

The W3C defines a Web service as:

A webservice becomes RESTful when the following 4 constraints are

satisfied.

1. Addressability

2. Multiple Representations

3. Uniform and constrained interfaces

4. Stateless communication

a software system designed to support interoperable

machine-to-machine interaction over a network.


How does RESTful web service work?

Two logical sections

Registration

Usage


Why?

POST /students/StudentsService HTTP/1.1

Host: http://localhost:8500

Content-Type: soap/xml

<Envelope>

<Header></Header>

<Body>

<GetStudent>

<Id>112</Id>

</GetStudent>

</Body>

<Envelope>

GET /students/112 HTTP/1.1

Host: http://localhost:8500

Accepts: text/html

Traditional web service

RESTful web service


Registration Workflow

Registration is the process of making your service ready for use.

27

Register application

Scanning for REST

CFC

Generate skeleton

Annotate skeleton

Register with Jersey

Inputs: Application Root Path and Service Name


Settings

28

Register application

Scanning for REST

CFC

• restsettings.cfclocation

Generate skeleton

• restsettings.skipCFCWithError

Annotate skeleton

Register with Jersey


Usage Workflow

Inputs: HTTP request

The URL of the request

HTTP Headers

Body of the request

Query params, Cookies, Matrix params etc..

29


Explaning the URL

http:// + localhost:8500 + /rest + /examples + /helloworld

30

• The protocolhttp

• Server address and portlocalhost:8500

• Context path used to identify the request as a REST requestrest

• The application name used during registrationexamples

• restPath defined in the CFChelloworld


Request Workflow

31

Identify REST

request

Identifies application

Identifies CFC

Identifies function

Invokes Function


Settings

32

Identify REST

request

• Change context path in web.xml

Identifies application

• Can make application default if needed

Identifies CFC

Identifies function

Invokes Function

• use custom serializer to modify response


Summary

RESTful web services introduction

33

Why RESTful web service needs to be registered first?

Registration workflow

o Settings

Request Workflow

Settings


Q & A

[email protected]

http://blogs.coldfusion.com/


Software

ColdFusion Internals