org.esigate.extension.surrogate

Class Surrogate

java.lang.Object

org.esigate.extension.surrogate.Surrogate

All Implemented Interfaces:

IEventListener, Extension

public class Surrogate
extends Object
implements Extension, IEventListener

Implementation of Edge-Arch specification 1.0.

See :

• http://www.w3.org/TR/edge-arch
• http://docs.oracle.com/cd/E17904_01/web.1111/e10143/esi.htm

This extension allows control of esigate features from the provider application.

This extension cooperates with other extensions to get the currently supported capabilities. To participate to capabilities collection, and extension should register to EVENT_SURROGATE_CAPABILITIES and provide capabilities when the event is fired.

 driver.getEventManager().register(Surrogate.EVENT_SURROGATE_CAPABILITIES, new IEventListener() {
     public boolean event(EventDefinition id, Event event) {
         CapabilitiesEvent capEvent = (CapabilitiesEvent) event;
         capEvent.capabilities.add("ESI/1.0");
         capEvent.capabilities.add("ESI-Inline/1.0");
         capEvent.capabilities.add("ESIGATE/4.0");
         return true;
     }
 });
 

The provider may respond with control directive. In that case, the extension should ensure that its capability are requested and do not process response otherwise.

  if (renderEvent.httpResponse.containsHeader(Surrogate.H_X_ENABLED_CAPABILITIES)) {
      String capabilities = renderEvent.httpResponse.getFirstHeader(Surrogate.H_X_ENABLED_CAPABILITIES).getValue();
 
      if (!containsIgnoreCase(capabilities, "ESI/1.0") {
          // Cancel processing
      }
  }
 

Targeting is supported.

NOTE:

• no-store-remote is not honored since esigate is generally not used as a CDN.

Author:

Nicolas Richeton

Field Summary

Fields

Modifier and Type	Field and Description
static EventDefinition	EVENT_SURROGATE_CAPABILITIES This event is fired on startup to collect all installed capabilities.
static String	H_X_ENABLED_CAPABILITIES This is an internal header, used to track the requested capabilities.

Constructor Summary

Constructors

Constructor and Description
Surrogate()

Method Summary

Modifier and Type	Method and Description
boolean	event(EventDefinition id, Event event) Handle an event.
void	init(Driver driver, Properties properties) Initialize the extension using the given properties.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

H_X_ENABLED_CAPABILITIES

public static final String H_X_ENABLED_CAPABILITIES

This is an internal header, used to track the requested capabilities.

Value is the value of the content directive from the Surrogate-Control header.

See Also:

Constant Field Values

EVENT_SURROGATE_CAPABILITIES

public static final EventDefinition EVENT_SURROGATE_CAPABILITIES

This event is fired on startup to collect all installed capabilities.

Constructor Detail

Surrogate

public Surrogate()

Method Detail

init

public void init(Driver driver,
                 Properties properties)

Description copied from interface: Extension

Initialize the extension using the given properties.

Extensions may register to events during the init phase.

Specified by:

init in interface Extension

event

public boolean event(EventDefinition id,
                     Event event)

Description copied from interface: IEventListener

Handle an event.

Specified by:

event in interface IEventListener

Returns:

false to stop the processing of event listeners for this event