everest iPOJO Service Providing Resources

This is the documentation of the Service Providing Resources of the everest iPOJO domain. Each service providing of an iPOJO component instance is represented by an everest iPOJO service providing resource.

Path

/ipojo/instance/$name/providing/$index - Where $name stand for the name of the instance and $index for the index of the providing.

Supported operations

READ: get the current state of the service dependency.
UPDATE: reconfigure the providing
- state (string): the wanted state for the providing. One of {“REGISTERED”, “UNREGISTERED”}. May be null.

NOTE: This type of resource is observable

Metadata

serviceSpecifications (string array): The specification of the provided service.
policy (string): The providing policy if the service. One of {“SINGLETON_STRATEGY”, “SERVICE_STRATEGY”, “STATIC_STRATEGY”, “INSTANCE_STRATEGY”, “CUSTOM_STRATEGY”, “unknown”}.
creationStrategy (string): The name of the CreationStrategy class for the service providing.
controller (string): The provided service controller.
state (string): The current state of the provided service. One of {“REGISTERED”, “UNREGISTERED”}.
properties (map): The current properties exposed by the provided service.
__isFake (boolean): Set to true if the resource is a fake resource. Unset otherwise.

Relations

service: to the provided OSGi service.

Supported Adaptations

to org.apache.felix.ipojo.handlers.providedservice.ProvidedService.class: to the iPOJO ProvidedService.
to org.apache.felix.ipojo.handlers.providedservice.ProvidedServiceDescription.class: to the iPOJO ProvidedServiceDescription.
to org.osgi.framework.ServiceReference.class: to the reference of the currently provided service. null if the service is not currently provided.

HOW-TOs

How to reconfigure providings

You can reconfigure dynamically service providings by sending an UPDATE request on their resource representation. For now, the only possible action is to register/unregister the service. Here is a quick example:

Request:

UPDATE /ipojo/instance/org.ow2.chameleon.everest.core.Everest-0/providing/0
- state="unregistered"

Result:

{
  "state":"UNREGISTERED",
  ...
}

WARNING: Reconfiguring the service providings may have quite strange side effects on the component instance, especially if it has a service controller or providing callbacks. Prepare for unforeseen consequences…

NOTE: The above example is a perfect illustration of a BAD example. If you are wondering why: it is exactly as cutting off the branch you’re sitting on. Prepare for predictable resource damages.

Example

READ /ipojo/instance/org.ow2.chameleon.everest.core.Everest-0/providing/0

{
  "state":"REGISTERED",
  "properties": {
    "factory.name":"org.ow2.chameleon.everest.core.Everest",
    "instance.name":"org.ow2.chameleon.everest.core.Everest-0"
  },
  "__relations": {
    "service": {
      "href":"http://localhost:8080/everest/osgi/services/73",
      "action":"READ",
      "name":"service",
      "description":"Provided service",
      "parameters":[]
    }
  },
  "__observable":true
}