RepositoryImpl Configurer

The Purpose

Each project inside Semantic Turkey is associated with a local RDF4J RepositoryManager that is in charge of managing the lifecycle of the RDF repositories backing the project. Indeed, a project has always a core repository containing the data being edited, and optionally a support repository containing history/validation metadata. Additional repositories can be created for different purposes, such as creating a snapshot of a specific version of the core repository. A RepositoryImplConfigurer is able to configure a specific type of repository.

The Model

In RDF4J the configuration of a repository ( RepositoryConfig) contains a reference to a RepositoryImplConfig, which tells the nature of the repository (e.g. a sail-based one, or a remote repository) together with specific configuration properties. Semantic Turkey neatly distinguishes remote repositories from local ones, since the former are managed natively by Semantic Turkey, while in the latter case a RepositoryImplConfigurer is used to instantiate the repository configuration. Assuming that the configured repository is sail-based, an optional function is passed to the configurer, which is in charge to decorate the backend sail with further sails, such as the one implementing history/validation.

Extension Point Details

The tables below summarizes the details of the RepositoryImplConfigurer extension point.

Interfaces

The following interface defines the contract for the RepositoryImplConfigurer extension point.

/**
* A component providing the configuration for a {@link RepositoryImplConfig}.
*/
public interface RepositoryImplConfigurer extends Extension {
	/**
	* Builds a {@link RepositoryImplConfig}, considering the provided <code>backend decorator</code> (if not
	* <code>null</code>). A <code>backend decorator</code> wraps the backed sail with any stackable sail
	* (useful to add history/validation).
	* 
	* @param backendDecorator
	* @return
	*/
	RepositoryImplConfig buildRepositoryImplConfig(
			@Nullable Function<SailImplConfig, SailImplConfig> backendDecorator);
}

Choosing and Configuring a RepositoryImpl Configurer

RepositoryImplConfigurer can be created on demand by the system as it is needed to create a local repository or to create a repository on a remote server. Nonetheless, they are usually configurable components, the configurations of which can be stored according to the standard configuration/settings mechanism.

RepositoryImplConfigurer Implementations

Predefined RepositoryImpl Configurer

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