atscppapi::TransformationPlugin Class Reference

The interface used when you wish to transform Request or Response body content. More...

#include <TransformationPlugin.h>

Inherits atscppapi::TransactionPlugin.

Inherited by atscppapi::transformations::GzipDeflateTransformation, and atscppapi::transformations::GzipInflateTransformation.

Collaboration diagram for atscppapi::TransformationPlugin:

Public Types
enum	Type { REQUEST_TRANSFORMATION = 0, RESPONSE_TRANSFORMATION }
	The available types of Transformations. More...
Public Member Functions
virtual void	consume (const std::string &data)=0
	A method that you must implement when writing a TransformationPlugin, this method will be fired whenever an upstream TransformationPlugin has produced output.
virtual void	handleInputComplete ()=0
	A method that you must implement when writing a TransformationPlugin, this method will be fired whenever the upstream TransformationPlugin has completed writing data.
virtual	~TransformationPlugin ()
	Destructor for a TransformationPlugin.
Protected Member Functions
size_t	produce (const std::string &)
	This method is how a TransformationPlugin will produce output for the downstream transformation plugin, if you need to produce binary data this can still be done with strings by a call to string::assign() or by constructing a string with string::string(char *, size_t).
size_t	setOutputComplete ()
	This is the method that you must call when you're done producing output for the downstream TranformationPlugin.
	TransformationPlugin (Transaction &transaction, Type type)
	a TransformationPlugin must implement this interface, it cannot be constructed directly

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Detailed Description

The interface used when you wish to transform Request or Response body content.

Transformations are deceptively simple, transformations are chained so the output of one TransformationPlugin becomes the input of another TransformationPlugin. As data arrives it will fire a consume() and when all the data has been sent you will receive a handleInputComplete(). Data can be sent to the next TransformationPlugin in the chain by calling produce() and when the transformation has no data left to send it will fire a setOutputCompete().

Since a TransformationPlugin is a type of TransactionPlugin you can call registerHook() and establish any hook for a Transaction also; however, remember that you must implement the appropriate callback for any hooks you register.

A simple example of how to use the TransformationPlugin interface follows, this is an example of a Response transformation, the avialable options are REQUEST_TRANSFORMATION and RESPONSE_TRANSFORMATION which are defined in Type.

This example is a Null Transformation, meaning it will just spit out the content it receives without actually doing any work on it.

 class NullTransformationPlugin : public TransformationPlugin {
 public:
   NullTransformationPlugin(Transaction &transaction)
     : TransformationPlugin(transaction, RESPONSE_TRANSFORMATION) {
     registerHook(HOOK_SEND_RESPONSE_HEADERS);
   }
   void handleSendResponseHeaders(Transaction &transaction) {
     transaction.getClientResponse().getHeaders().set("X-Content-Transformed", "1");
     transaction.resume();
   }
   void consume(const string &data) {
     produce(data);
   }
   void handleInputComplete() {
     setOutputComplete();
   }
 };

See also:

Plugin

TransactionPlugin

Type

HookType

Definition at line 81 of file TransformationPlugin.h.

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Member Enumeration Documentation

enum atscppapi::TransformationPlugin::Type

The available types of Transformations.

Enumerator:

REQUEST_TRANSFORMATION	Transform the Request body content.
RESPONSE_TRANSFORMATION	Transform the Response body content.

Definition at line 86 of file TransformationPlugin.h.

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Constructor & Destructor Documentation

virtual atscppapi::TransformationPlugin::~TransformationPlugin

(

)

[virtual]

Destructor for a TransformationPlugin.

atscppapi::TransformationPlugin::TransformationPlugin	(	Transaction &	transaction,
		Type	type
	)			[protected]

a TransformationPlugin must implement this interface, it cannot be constructed directly

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Member Function Documentation

virtual void atscppapi::TransformationPlugin::consume

(

const std::string &

data

)

[pure virtual]

A method that you must implement when writing a TransformationPlugin, this method will be fired whenever an upstream TransformationPlugin has produced output.

Implemented in atscppapi::transformations::GzipDeflateTransformation, and atscppapi::transformations::GzipInflateTransformation.

virtual void atscppapi::TransformationPlugin::handleInputComplete

(

)

[pure virtual]

A method that you must implement when writing a TransformationPlugin, this method will be fired whenever the upstream TransformationPlugin has completed writing data.

Implemented in atscppapi::transformations::GzipDeflateTransformation, and atscppapi::transformations::GzipInflateTransformation.

size_t atscppapi::TransformationPlugin::produce

(

const std::string &

)

[protected]

This method is how a TransformationPlugin will produce output for the downstream transformation plugin, if you need to produce binary data this can still be done with strings by a call to string::assign() or by constructing a string with string::string(char *, size_t).

size_t atscppapi::TransformationPlugin::setOutputComplete

(

)

[protected]

This is the method that you must call when you're done producing output for the downstream TranformationPlugin.

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The documentation for this class was generated from the following file:

• TransformationPlugin.h