// TODO check whether transactions are supported by the storage provider to make those as atomical as possible
/// <summary>
/// Flushes changes to the dataset
/// TODO handle dataset changes as updates instread of overwriting it to make it workable in a concurrent environment.
/// </summary>
public void Flush()
{
if (!Configuration.IsChanged)
{
return;
}
// TODO check if the updates did not raise any constraint violation, otherwise reject the Flush request
// TODO related to the concurrency policy problem : handle any concurrent updates may have happened and succeded between the first modification and here
SpinDatasetDescription updatedSourceDataset = new SpinDatasetDescription(Configuration.SourceUri);
updatedSourceDataset.Assert(Configuration.GetTriplesWithPredicateObject(RDF.PropertyType, SPIN.ClassLibraryOntology));
updatedSourceDataset.Assert(Configuration.GetTriplesWithPredicateObject(RDF.PropertyType, SD.ClassGraph));
foreach (SpinWrappedGraph g in Configuration.ModificableGraphs)
{
Uri updatedGraphUri = Configuration.GetUpdateControlUri(g.BaseUri);
Uri sourceGraph = g.BaseUri;
if (Configuration.IsGraphReplaced(sourceGraph))
{
Storage.Update("WITH <" + updatedGraphUri.ToString() + "> DELETE { ?s <" + RDFRuntime.PropertyResets.Uri.ToString() + "> ?p } WHERE { ?s <" + RDFRuntime.PropertyResets.Uri.ToString() + "> ?p }"); // For safety only
Storage.Update("MOVE GRAPH <" + updatedGraphUri.ToString() + "> TO <" + sourceGraph.ToString() + ">");
}
else if (Configuration.IsGraphUpdated(sourceGraph))
{
Storage.Update("DELETE { GRAPH <" + updatedGraphUri.ToString() + "> { ?s <" + RDFRuntime.PropertyResets.Uri.ToString() + "> ?p } . GRAPH <" + sourceGraph.ToString() + "> { ?s ?p ?o } } USING <" + updatedGraphUri.ToString() + "> USING NAMED <" + g.BaseUri.ToString() + "> WHERE { ?s <" + RDFRuntime.PropertyResets.Uri.ToString() + "> ?p . GRAPH <" + g.BaseUri.ToString() + "> { ?s ?p ?o} }");
Storage.Update("ADD GRAPH <" + updatedGraphUri.ToString() + "> TO <" + sourceGraph.ToString() + ">");
}
else
{
updatedSourceDataset.Retract(Configuration.GetTriplesWithSubject(RDFUtil.CreateUriNode(sourceGraph)));
}
}
// TODO update the original dataset instead of overwriting it
Storage.SaveGraph(updatedSourceDataset);
DisposeUpdateControlledDataset();
}
/// <summary>
/// Inititalize a SpinWrapperDataset upon a storage engine using a RDF SparqlDataset definition.
/// </summary>
/// <param name="datasetUri"></param>
/// <param name="storage"></param>
public SpinWrappedDataset(Uri datasetUri, IUpdateableStorage storage)
{
Storage = storage;
Configuration = SpinDatasetDescription.Load(Storage, datasetUri);
Initialise();
}
/// <summary>
/// Inititalize a SpinWrapperDataset upon a storage engine using all the graphs in the store.
/// </summary>
/// <param name="storage"></param>
internal SpinWrappedDataset(IUpdateableStorage storage)
{
Storage = storage;
Configuration = SpinDatasetDescription.Load(Storage);
Initialise();
}
/// <summary>
/// Inititalize a SPIN model upon a storage engine using a RDF SparqlDataset definition composed of the specified graphs.
/// </summary>
/// <param name="datasetUri"></param>
/// <param name="storage"></param>
/// <param name="graphUris"></param>
public SpinWrappedDataset(Uri datasetUri, IUpdateableStorage storage, IEnumerable <Uri> graphUris)
{
Storage = storage;
Configuration = SpinDatasetDescription.Load(Storage, datasetUri, graphUris);
Initialise();
}