Package org.apache.stanbol.enhancer.servicesapi

Stanbol Enhancer services API

See:
Description

Interface Summary

Blob	represents a finite sequence of bytes associated to a mime-type
Chain	An Enhancement Chain represents a configuration that defines what engines and in what order are used to process ContentItems.
ChainManager	Interface that allows to lookup ServiceReference and Chain services based on the name.
ContentItem	A unit of content that Stanbol Enhancer can enhance.
Enhancement	This Interface represents a Stanbol Enhancer enhancement.
EnhancementEngine	Interface to internal or external semantic enhancement engines.
EnhancementEngineManager	Interface that allows to lookup ServiceReference and EnhancementEngine services based on the name.
EnhancementJobManager	Accept requests for enhancing ContentItems, and processes them either synchronously or asynchronously (as decided by the enhancement engines, the job manager implementation, the execution plan provided by the Chain or by some additional configurations).
EntityAnnotation
ServiceProperties	Stanbol Enhancer components might implement this interface to parse additional properties to other components.
SparqlQueryEngine	SPARQL query engine interface.
TextAnnotation

Exception Summary

ChainException	BaseException thrown by Chain implementations or EnhancementJobManager implementations when encountering problems while executing e Chain
EngineException	Base exception thrown by EnhancementEngine implementations when they fail to process the provided content item.
EnhancementException	Abstract super class over EngineException and Chain as typically used by components that need to used both EnhancementEngines and Chains.
InvalidContentException	Enhancement Engine should throw this exception when the provided Content Item does not match there declared expectation (i.e.
NoSuchPartException	Indicates that a COntent Item doesn't has the requested part
SparqlQueryEngine.SparqlQueryEngineException

Package org.apache.stanbol.enhancer.servicesapi Description

Stanbol Enhancer services API

The Stanbol Enhancer services API defines the service interfaces for the components that collaborate to implement a Stanbol enhancement server.

See FISEcodeAndDocs on the IKS wiki for more information about Stanbol Enhancer (formally called IKS FISE).

The API has almost no external dependencies and is independent of OSGi or any other components model.

It currently has a dependency on the Clerezza MGraph interface, but we might want to replace that with a more generic "annotations" interface.

Main design goals

The Stanbol enhancement server aims to:

• Make it very easy to use it as an external content enhancement/search engine, with a simple RESTful HTTP interface. Client PUTs or POSTs a piece of content to the Stanbol Enhancer, and can then retrieve the enhancements produced by the EnhancementEngine that are active in the Stanbol Enhancement server, with a GET request.
• Make it simple for providers of enhancement engines (annotation, geolocation, etc...) to plug them into a Stanbol Enhancement server. With the current implementation, one just needs to implement a new EnhancementEngine and supply it as an OSGi service in an OSGi bundle. See the Autotagging engine for an example that wraps a non-OSGi java content enhancement library.

TODO should we say "annotation" instead of "enhancement", and rename the interfaces accordingly?

Main Stanbol Enhancer use-case

To help understand the API, here's an overview of the main Stanbol Enhancer use-case:

• Client PUTs or POSTs a piece of content to register it with Enhancer, supplied as a binary stream with a Content-Type (and optional initial metadata - not currently implemented).
• The EnhancementJobManager goes through its list of EnhancementEngine and finds out which ones can process the incoming ContentItem. An engine can suggest enhancing the content synchronously or assynchronously, and the job manager can override those suggestions.
• The client GETs the ContentItem using the same URL that it used in the previous PUT request, or the URL supplied by Enhancer (Location header) if a POST request was used to register the content.
• As some enhancement requests might be asynchronous, the returned data might include process information, for example "3 requests for enhancement still pending".

That's it. Not too hard.