/// <summary>
/// Processes requests
/// </summary>
/// <param name="context">HTTP Context</param>
public void ProcessRequest(HttpContext context)
{
this._config = this.LoadConfig(context, out this._basePath);
//Add our Standard Headers
HandlerHelper.AddStandardHeaders(context, this._config);
String path = context.Request.Path;
if (path.StartsWith(this._basePath))
{
path = path.Substring(this._basePath.Length);
}
//Q: Commented out as current Service Description draft specifications says only a single Service can be described in a document. Reinstate if drafts change?
//if (context.Request.HttpMethod.Equals("OPTIONS"))
//{
// //OPTIONS requests always result in the Service Description document
// IGraph svcDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, new Uri(new Uri(context.Request.Url.AbsoluteUri), this._basePath + "description"));
// HandlerHelper.SendToClient(context, svcDescrip, this._config);
//}
//else
//{
switch (path)
{
case "query":
this.ProcessQueryRequest(context);
break;
case "update":
this.ProcessUpdateRequest(context);
break;
//case "description":
// this.ProcessDescriptionRequest(context);
// break;
default:
this.ProcessProtocolRequest(context);
break;
}
//}
}
/// <summary>
/// Processes requests
/// </summary>
/// <param name="context">HTTP Context</param>
public void ProcessRequest(HttpContext context)
{
this._config = this.LoadConfig(context, out this._basePath);
//Add our Standard Headers
HandlerHelper.AddStandardHeaders(context, this._config);
String path = context.Request.Path;
if (path.StartsWith(this._basePath))
{
path = path.Substring(this._basePath.Length);
}
//OPTIONS requests always result in the Service Description document
if (context.Request.HttpMethod.Equals("OPTIONS"))
{
IGraph svcDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, new Uri(new Uri(context.Request.Url.AbsoluteUri), this._basePath + "description"), ServiceDescriptionType.All);
HandlerHelper.SendToClient(context, svcDescrip, this._config);
}
else
{
//Otherwise determine the type of request based on the Path
switch (path)
{
case "query":
this.ProcessQueryRequest(context);
break;
case "update":
this.ProcessUpdateRequest(context);
break;
case "description":
this.ProcessDescriptionRequest(context);
break;
default:
this.ProcessProtocolRequest(context);
break;
}
}
}
/// <summary>
/// Generates a SPARQL Service Description Graph for the specified portion of the SPARQL Server Handler Configuration or uses the configuration supplied Description Graph
/// </summary>
/// <param name="context">HTTP Context</param>
/// <param name="config">SPARQL Server Configuration</param>
/// <param name="descripUri">Base URI of the Description</param>
/// <param name="type">Portion of the SPARQL Server to describe</param>
/// <returns></returns>
public static IGraph GetServiceDescription(HttpContext context, BaseSparqlServerConfiguration config, Uri descripUri, ServiceDescriptionType type)
{
//Use user specified Service Description if present
if (config.ServiceDescription != null) return config.ServiceDescription;
IGraph g = SparqlServiceDescriber.GetNewGraph();
IUriNode rdfType = g.CreateUriNode(new Uri(RdfSpecsHelper.RdfType));
IUriNode service = g.CreateUriNode("sd:" + ClassService);
INode queryNode, updateNode, protocolNode;
//Query Service Description
if (config.QueryProcessor != null && (type == ServiceDescriptionType.Query || type == ServiceDescriptionType.All))
{
//Add the Top Level Node representing the Query Service
queryNode = g.CreateUriNode(new Uri(descripUri, "query"));
g.Assert(queryNode, rdfType, service);
//Add its sd:url
IUriNode url = g.CreateUriNode("sd:" + PropertyUrl);
g.Assert(queryNode, url, queryNode);
//Add the sd:supportedLanguage
IUriNode supportedLang = g.CreateUriNode("sd:" + PropertySupportedLanguage);
IUriNode lang;
switch (config.QuerySyntax)
{
case SparqlQuerySyntax.Extended:
case SparqlQuerySyntax.Sparql_1_1:
lang = g.CreateUriNode("sd:" + InstanceSparql11Query);
break;
default:
lang = g.CreateUriNode("sd:" + InstanceSparql10Query);
break;
}
g.Assert(queryNode, supportedLang, lang);
//Add the Result Formats
IUriNode resultFormat = g.CreateUriNode("sd:" + PropertyResultFormat);
foreach (MimeTypeDefinition definition in MimeTypesHelper.Definitions)
{
if (definition.CanWriteRdf || definition.CanWriteSparqlResults)
{
if (definition.FormatUri != null)
{
g.Assert(queryNode, resultFormat, g.CreateUriNode(new Uri(definition.FormatUri)));
}
}
}
//Add Features and Dataset Description
//First add descriptions for Global Expression Factories
IUriNode extensionFunction = g.CreateUriNode("sd:" + PropertyExtensionFunction);
IUriNode extensionAggregate = g.CreateUriNode("sd:" + PropertyExtensionAggregate);
foreach (ISparqlCustomExpressionFactory factory in SparqlExpressionFactory.Factories)
{
foreach (Uri u in factory.AvailableExtensionFunctions)
{
g.Assert(queryNode, extensionFunction, g.CreateUriNode(u));
}
foreach (Uri u in factory.AvailableExtensionAggregates)
{
g.Assert(queryNode, extensionAggregate, g.CreateUriNode(u));
}
}
}
else
{
queryNode = null;
}
//Update Service Description
if (config.UpdateProcessor != null && (type == ServiceDescriptionType.Update || type == ServiceDescriptionType.All))
{
//Add the Top Level Node representing the Update Service
updateNode = g.CreateUriNode(new Uri(descripUri, "update"));
g.Assert(updateNode, rdfType, service);
//Add its sd:url
IUriNode url = g.CreateUriNode("sd:" + PropertyUrl);
g.Assert(updateNode, url, updateNode);
//Add the sd:supportedLanguage
IUriNode supportedLang = g.CreateUriNode("sd:" + PropertySupportedLanguage);
g.Assert(updateNode, supportedLang, g.CreateUriNode("sd:" + InstanceSparql11Update));
//Add Features and Dataset Description
//First add descriptions for Global Expression Factories
IUriNode extensionFunction = g.CreateUriNode("sd:" + PropertyExtensionFunction);
IUriNode extensionAggregate = g.CreateUriNode("sd:" + PropertyExtensionAggregate);
foreach (ISparqlCustomExpressionFactory factory in SparqlExpressionFactory.Factories)
{
foreach (Uri u in factory.AvailableExtensionFunctions)
{
g.Assert(updateNode, extensionFunction, g.CreateUriNode(u));
}
foreach (Uri u in factory.AvailableExtensionAggregates)
{
g.Assert(updateNode, extensionAggregate, g.CreateUriNode(u));
}
}
}
else
{
updateNode = null;
}
//Graph Store HTTP Protocol Description
if (config.ProtocolProcessor != null && (type == ServiceDescriptionType.Protocol || type == ServiceDescriptionType.All))
{
//Add the Top Level Node representing the Service
if (descripUri.ToString().EndsWith("/description"))
{
String actualUri = descripUri.ToString();
actualUri = actualUri.Substring(0, actualUri.LastIndexOf("/description") + 1);
protocolNode = g.CreateUriNode(new Uri(actualUri));
}
else
{
protocolNode = g.CreateUriNode(descripUri);
}
g.Assert(protocolNode, rdfType, service);
//Add its sd:url
IUriNode url = g.CreateUriNode("sd:" + PropertyUrl);
g.Assert(protocolNode, url, protocolNode);
//Add the Input Formats
IUriNode inputFormat = g.CreateUriNode("sd:" + PropertyInputFormat);
foreach (MimeTypeDefinition definition in MimeTypesHelper.Definitions)
{
if (definition.CanParseRdf)
{
if (definition.FormatUri != null)
{
g.Assert(protocolNode, inputFormat, g.CreateUriNode(new Uri(definition.FormatUri)));
}
}
}
//Add the Result Formats
IUriNode resultFormat = g.CreateUriNode("sd:" + PropertyResultFormat);
foreach (MimeTypeDefinition definition in MimeTypesHelper.Definitions)
{
if (definition.CanWriteRdf)
{
if (definition.FormatUri != null)
{
g.Assert(protocolNode, resultFormat, g.CreateUriNode(new Uri(definition.FormatUri)));
}
}
}
}
else
{
protocolNode = null;
}
//Finally get the Configuration Node to add additional feature and dataset descriptions
config.AddFeatureDescription(g, queryNode, updateNode, protocolNode);
return g;
}
