/// <summary>
        /// Saves a Graph to the Protocol Server
        /// </summary>
        /// <param name="g">Graph to save</param>
        public virtual void SaveGraph(IGraph g)
        {
            String saveUri = _serviceUri;

            if (g.BaseUri != null)
            {
                saveUri += "?graph=" + Uri.EscapeDataString(g.BaseUri.AbsoluteUri);
            }
            else
            {
                saveUri += "?default";
            }
            try
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(UriFactory.Create(saveUri));
                request.Method = "PUT";
                //request.ContentType = MimeTypesHelper.RdfXml[0];
                request.ContentType = _writerMimeTypeDefinition.CanonicalMimeType;
                request             = ApplyRequestOptions(request);

                //RdfXmlWriter writer = new RdfXmlWriter();
                IRdfWriter writer = _writerMimeTypeDefinition.GetRdfWriter();
                writer.Save(g, new StreamWriter(request.GetRequestStream()));

                Tools.HttpDebugRequest(request);

                using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
                {
                    Tools.HttpDebugResponse(response);
                    // If we get here then it was OK
                    response.Close();
                }
            }
            catch (WebException webEx)
            {
                throw StorageHelper.HandleHttpError(webEx, "saving a Graph to");
            }
        }
Пример #2
0
        /// <summary>
        /// Sends the given Graph to the Client via the HTTP Response.
        /// </summary>
        /// <param name="context">HTTP Context.</param>
        /// <param name="g">Graph to send.</param>
        protected void SendResultsToClient(IHttpContext context, IGraph g)
        {
            IRdfWriter writer;
            String     ctype;

            // Look up the MIME Type Definition - if none use GetWriter instead
            MimeTypeDefinition definition = MimeTypesHelper.GetDefinitions(context.GetAcceptTypes()).FirstOrDefault(d => d.CanWriteRdf);

            if (definition != null)
            {
                writer = definition.GetRdfWriter();
                ctype  = definition.CanonicalMimeType;
            }
            else
            {
                writer = MimeTypesHelper.GetWriter(context.GetAcceptTypes(), out ctype);
            }

            // Set up the Writer
            if (writer is ICompressingWriter)
            {
                ((ICompressingWriter)writer).CompressionLevel = Options.DefaultCompressionLevel;
            }

            // Send Content to Client
            context.Response.ContentType = ctype;
            if (definition != null)
            {
                context.Response.ContentEncoding = definition.Encoding;
                writer.Save(g, new StreamWriter(context.Response.OutputStream, definition.Encoding));
            }
            else
            {
                writer.Save(g, new StreamWriter(context.Response.OutputStream));
            }
        }
Пример #3
0
        public void RunConvert(String[] args)
        {
            //Set the Options
            if (!this.SetOptions(args))
            {
                //If SetOptions returns false then some options were invalid and errors have been output to the error stream
                return;
            }

            //First grab the MIME Type Definitions for the conversion
            List <MimeTypeDefinition> defs = MimeTypesHelper.GetDefinitions(this._outFormats).ToList();

            //Process each input to determine the Conversion Handler to use
            foreach (IConversionInput input in this._inputs)
            {
                String outFile;
                String ext = this._outExt;

                //First determine the writer we'll use
                MimeTypeDefinition graphDef = defs.FirstOrDefault(d => d.CanWriteRdf);
                if (graphDef != null)
                {
                    //Then generate the output filename
                    if (ext.Equals(String.Empty))
                    {
                        ext = "." + graphDef.CanonicalFileExtension;
                    }
                    if (this._inputs.Count == 1 && !this._outputFilename.Equals(String.Empty))
                    {
                        outFile = this._outputFilename;
                    }
                    else
                    {
                        outFile = input.GetFilename(this._outputFilename, ext);
                    }

                    //Check it doesn't already exist or overwrite is enabled
                    if (File.Exists(outFile) && !this._overwrite)
                    {
                        Console.Error.WriteLine("rdfConvert: Warning: Skipping Conversion of Input " + input.ToString() + " as this would generate the Output File '" + outFile + "' which already exists and the -overwrite option was not specified");
                        continue;
                    }

                    //Get the Writer and apply Conversion Options
                    IRdfWriter writer = graphDef.GetRdfWriter();
                    foreach (IConversionOption option in this._options)
                    {
                        option.Apply(writer);
                    }

                    //If -best always use SaveOnCompletionHandler
                    if (this._best)
                    {
                        if (this._verbose)
                        {
                            Console.WriteLine("rdfConvert: Using Best Quality data conversion subject to user specified compression options");
                        }
                        input.ConversionHandler = new SaveOnCompletionHandler(writer, new StreamWriter(outFile, false, graphDef.Encoding));
                    }
                    else
                    {
                        //Use the fast WriteThroughHandler where possible
                        if (writer is IFormatterBasedWriter)
                        {
                            if (this._verbose)
                            {
                                Console.WriteLine("rdfConvert: Using Streaming Conversion with formatter " + ((IFormatterBasedWriter)writer).TripleFormatterType.Name);
                            }
                            input.ConversionHandler = new WriteToFileHandler(outFile, graphDef.Encoding, ((IFormatterBasedWriter)writer).TripleFormatterType);
                        }
                        else
                        {
                            //Can't use it in this case
                            if (this._verbose)
                            {
                                Console.WriteLine("rdfConvert: Warning: Target Format not suitable for streaming conversion, input data will be loaded into memory prior to conversion");
                            }
                            input.ConversionHandler = new SaveOnCompletionHandler(writer, new StreamWriter(outFile, false, graphDef.Encoding));
                        }
                    }
                }
                else
                {
                    MimeTypeDefinition storeDef = defs.FirstOrDefault(d => d.CanWriteRdfDatasets);
                    if (storeDef != null)
                    {
                        //Then generate the output filename
                        if (ext.Equals(String.Empty))
                        {
                            ext = "." + storeDef.CanonicalFileExtension;
                        }
                        outFile = input.GetFilename(this._outputFilename, ext);

                        //Get the Writer and apply conversion options
                        IStoreWriter writer = storeDef.GetRdfDatasetWriter();
                        foreach (IConversionOption option in this._options)
                        {
                            option.Apply(writer);
                        }

                        //If -best always use SaveOnCompletionHandler
                        if (this._best)
                        {
                            if (this._verbose)
                            {
                                Console.WriteLine("rdfConvert: Using Best Quality  data conversion subject to user specified compression options");
                            }
                            input.ConversionHandler = new SaveStoreOnCompletionHandler(writer, new StreamWriter(outFile, false, storeDef.Encoding));
                        }
                        else
                        {
                            //Use the fast WriteThroughHandler where possible
                            if (writer is IFormatterBasedWriter)
                            {
                                if (this._verbose)
                                {
                                    Console.WriteLine("rdfConvert: Using Streaming Conversion with formatter " + ((IFormatterBasedWriter)writer).TripleFormatterType.Name);
                                }
                                input.ConversionHandler = new WriteToFileHandler(outFile, graphDef.Encoding, ((IFormatterBasedWriter)writer).TripleFormatterType);
                            }
                            else
                            {
                                if (this._verbose)
                                {
                                    Console.WriteLine("rdfConvert: Warning: Target Format not suitable for streaming conversion, input data will be loaded into memory prior to conversion");
                                }
                                input.ConversionHandler = new SaveStoreOnCompletionHandler(writer, new StreamWriter(outFile, false, storeDef.Encoding));
                            }
                        }
                    }
                    else
                    {
                        Console.Error.WriteLine("rdfConvert: Warning: Skipping Conversion of Input " + input.ToString() + " as unable to determine how to convert it");
                        continue;
                    }
                }

                //Then do the Conversion
                Console.WriteLine("rdfConvert: Converting Input " + input.ToString() + " to '" + outFile + "'...");
                try
                {
                    if (this._verbose)
                    {
                        input.ConversionHandler = new ConversionProgressHandler(input.ConversionHandler);
                        Console.WriteLine("rdfConvert: Debug: Conversion Handler is " + input.ConversionHandler.GetType().FullName);
                    }
                    input.Convert();
                    Console.WriteLine("rdfConvert: Converted Input " + input.ToString() + " to '" + outFile + "' OK");
                }
                catch (RdfParseException parseEx)
                {
                    Console.Error.WriteLine("rdfConvert: Error: Error Converting Input " + input.ToString() + " due to a RDF Parse Exception");
                    Console.Error.WriteLine(parseEx.Message);
                    if (this._debug)
                    {
                        this.DebugErrors(parseEx);
                    }
                }
                catch (RdfException rdfEx)
                {
                    Console.Error.WriteLine("rdfConvert: Error: Error Converting Input " + input.ToString() + " due to a RDF Exception");
                    Console.Error.WriteLine(rdfEx.Message);
                    if (this._debug)
                    {
                        this.DebugErrors(rdfEx);
                    }
                }
                catch (Exception ex)
                {
                    Console.Error.WriteLine("rdfConvert: Error: Error Converting Input " + input.ToString() + " due to a Unexpected Exception");
                    Console.Error.WriteLine(ex.Message);
                    if (this._debug)
                    {
                        this.DebugErrors(ex);
                    }
                }
            }
        }
Пример #4
0
 /// <summary>
 /// Selects the Writer to use for sending the Graph to the Client
 /// </summary>
 /// <param name="definition">Selected MIME Type Definition</param>
 /// <returns></returns>
 /// <remarks>
 /// <para>
 /// Implementations may override this if they wish to substitute in an alternative writer for certain MIME types (e.g. as done by the <see cref="SchemaGraphHandler">SchemaGraphHandler</see>)
 /// </para>
 /// </remarks>
 protected virtual IRdfWriter SelectWriter(MimeTypeDefinition definition)
 {
     return definition.GetRdfWriter();
 }
        /// <summary>
        /// Processes SPARQL Update requests
        /// </summary>
        /// <param name="context">HTTP Context</param>
        public void ProcessRequest(HttpContext context)
        {
            this._config = this.LoadConfig(context);
            WebContext webContext = new WebContext(context);

            // Add our Standard Headers
            HandlerHelper.AddStandardHeaders(webContext, this._config);

            // Options we need to determine based on the HTTP Method used
            String[]      updates;
            String        updateText        = null;
            List <String> userDefaultGraphs = new List <String>();
            List <String> userNamedGraphs   = new List <String>();

            try
            {
                // Decide what to do based on the HTTP Method
                switch (context.Request.HttpMethod.ToUpper())
                {
                case "OPTIONS":
                    // OPTIONS requests always result in the Service Description document
                    IGraph svcDescrip = SparqlServiceDescriber.GetServiceDescription(this._config, UriFactory.Create(context.Request.Url.AbsoluteUri));
                    HandlerHelper.SendToClient(webContext, svcDescrip, this._config);
                    return;

                case "HEAD":
                    // Just return from a HEAD request
                    return;

                case "GET":
                    // A GET with an update parameter is a Bad Request
                    updates = context.Request.QueryString.GetValues("update");
                    if (updates != null && updates.Length > 0)
                    {
                        throw new ArgumentException("Updates cannot be submitted as GET requests");
                    }

                    // Otherwise GET either results in the Service Description if appropriately conneg'd or
                    // the update form if enabled

                    try
                    {
                        // If we might show the Update Form only show the Description if the selected writer is
                        // not a HTML writer
                        MimeTypeDefinition definition = MimeTypesHelper.GetDefinitions(webContext.GetAcceptTypes()).FirstOrDefault(d => d.CanWriteRdf);
                        if (definition != null)
                        {
                            IRdfWriter writer = definition.GetRdfWriter();
                            if (!(writer is IHtmlWriter))
                            {
                                // If not a HTML Writer selected then show the Service Description Graph
                                // unless an error occurs creating it
                                IGraph serviceDescrip = SparqlServiceDescriber.GetServiceDescription(this._config, UriFactory.Create(context.Request.Url.AbsoluteUri));
                                context.Response.ContentType     = definition.CanonicalMimeType;
                                context.Response.ContentEncoding = definition.Encoding;
                                writer.Save(serviceDescrip, new StreamWriter(context.Response.OutputStream, definition.Encoding));
                                return;
                            }
                        }
                    }
                    catch
                    {
                        // Ignore Exceptions - we'll just show the Query Form or return a 400 Bad Request instead
                    }

                    // If a Writer can't be selected then we'll either show the Update Form or return a 400 Bad Request
                    if (this._config.ShowUpdateForm)
                    {
                        this.ShowUpdateForm(context);
                    }
                    else
                    {
                        throw new ArgumentException("Updates cannot be submitted as GET requests");
                    }
                    return;

                case "POST":

                    if (context.Request.ContentType != null)
                    {
                        MimeTypeSelector contentType = MimeTypeSelector.Create(context.Request.ContentType, 0);
                        if (contentType.Type.Equals(MimeTypesHelper.WWWFormURLEncoded))
                        {
                            // Form URL Encoded was declared type so expect an update parameter in the Form parameters
                            updates = context.Request.Form.GetValues("update");
                            if (updates == null)
                            {
                                throw new ArgumentException("Required update parameter in POST body was missing");
                            }
                            if (updates.Length == 0)
                            {
                                throw new ArgumentException("Required update parameter in POST body was missing");
                            }
                            if (updates.Length > 1)
                            {
                                throw new ArgumentException("The update parameter was specified multiple times in the POST body");
                            }
                            updateText = updates[0];

                            // For Form URL Encoded the Using/Using Named Graphs may be specified by Form parameters
                            // Get the USING URIs (if any)
                            if (context.Request.Form["using-graph-uri"] != null)
                            {
                                userDefaultGraphs.AddRange(context.Request.Form.GetValues("using-graph-uri"));
                            }
                            // Get the USING NAMED URIs (if any)
                            if (context.Request.Form["using-named-graph-uri"] != null)
                            {
                                userNamedGraphs.AddRange(context.Request.Form.GetValues("using-named-graph-uri"));
                            }

                            break;
                        }
                        else if (contentType.Type.Equals(MimeTypesHelper.SparqlUpdate))
                        {
                            // application/sparql-update was declared type so expect utf-8 charset (if present)
                            if (contentType.Charset != null && !contentType.Charset.ToLower().Equals(MimeTypesHelper.CharsetUtf8))
                            {
                                throw new ArgumentException("HTTP POST request was received with a " + MimeTypesHelper.SparqlUpdate + " Content-Type but a non UTF-8 charset parameter");
                            }

                            using (StreamReader reader = new StreamReader(context.Request.InputStream))
                            {
                                updateText = reader.ReadToEnd();
                                reader.Close();
                            }

                            // For application/sparql-update the Using/Using Named Graphs may be specified by querystring parameters
                            // Get the USING URIs (if any)
                            if (context.Request.QueryString["using-graph-uri"] != null)
                            {
                                userDefaultGraphs.AddRange(context.Request.QueryString.GetValues("using-graph-uri"));
                            }
                            // Get the USING NAMED URIs (if any)
                            if (context.Request.QueryString["using-named-graph-uri"] != null)
                            {
                                userNamedGraphs.AddRange(context.Request.QueryString.GetValues("using-named-graph-uri"));
                            }

                            break;
                        }
                        else
                        {
                            throw new ArgumentException("HTTP POST made to SPARQL update endpoint had an invalid Content-Type header, only " + MimeTypesHelper.WWWFormURLEncoded + " and " + MimeTypesHelper.SparqlUpdate + " are acceptable");
                        }
                    }
                    throw new ArgumentException("HTTP POST made to SPARQL Query endpoint was missing the required Content-Type header");

                default:
                    throw new NotSupportedException("HTTP " + context.Request.HttpMethod.ToUpper() + " is not supported by a SPARQL Update endpoint");
                }

                // Clean up protocol provided dataset
                userDefaultGraphs.RemoveAll(g => String.IsNullOrEmpty(g));
                userNamedGraphs.RemoveAll(g => String.IsNullOrEmpty(g));

                // Now we're going to parse the Updates
                SparqlUpdateParser parser = new SparqlUpdateParser();
                parser.DefaultBaseUri      = context.Request.Url;
                parser.ExpressionFactories = this._config.ExpressionFactories;
                SparqlUpdateCommandSet commands = parser.ParseFromString(updateText);

                // Check whether we need to use authentication
                // If there are no user groups then no authentication is in use so we default to authenticated with no per-action authentication needed
                bool isAuth = true, requireActionAuth = false;
                if (this._config.UserGroups.Any())
                {
                    // If we have user
                    isAuth            = HandlerHelper.IsAuthenticated(webContext, this._config.UserGroups);
                    requireActionAuth = true;
                }
                if (!isAuth)
                {
                    return;
                }

                // First check actions to see whether they are all permissible and apply USING/USING NAMED parameters
                foreach (SparqlUpdateCommand cmd in commands.Commands)
                {
                    // Authenticate each action
                    bool actionAuth = true;
                    if (requireActionAuth)
                    {
                        actionAuth = HandlerHelper.IsAuthenticated(webContext, this._config.UserGroups, this.GetPermissionAction(cmd));
                    }
                    if (!actionAuth)
                    {
                        throw new SparqlUpdatePermissionException("You are not authorised to perform the " + this.GetPermissionAction(cmd) + " action");
                    }

                    // Check whether we need to (and are permitted to) apply USING/USING NAMED parameters
                    if (userDefaultGraphs.Count > 0 || userNamedGraphs.Count > 0)
                    {
                        BaseModificationCommand modify = cmd as BaseModificationCommand;
                        if (modify != null)
                        {
                            if (modify.GraphUri != null || modify.UsingUris.Any() || modify.UsingNamedUris.Any())
                            {
                                // Invalid if a command already has a WITH/USING/USING NAMED
                                throw new SparqlUpdateMalformedException("A command in your update request contains a WITH/USING/USING NAMED clause but you have also specified one/both of the using-graph-uri or using-named-graph-uri parameters which is not permitted by the SPARQL Protocol");
                            }
                            else
                            {
                                // Otherwise go ahead and apply
                                userDefaultGraphs.ForEach(u => modify.AddUsingUri(UriFactory.Create(u)));
                                userNamedGraphs.ForEach(u => modify.AddUsingNamedUri(UriFactory.Create(u)));
                            }
                        }
                    }
                }

                // Then assuming we got here this means all our actions are permitted so now we can process the updates
                this.ProcessUpdates(commands);

                // Flush outstanding changes
                this._config.Processor.Flush();

                // Update the Cache as the request may have changed the endpoint
                this.UpdateConfig(context);
            }
            catch (RdfParseException parseEx)
            {
                HandleErrors(context, "Parsing Error", updateText, parseEx, (int)HttpStatusCode.BadRequest);
            }
            catch (SparqlUpdatePermissionException permEx)
            {
                HandleErrors(context, "Permissions Error", updateText, permEx, (int)HttpStatusCode.Forbidden);
            }
            catch (SparqlUpdateMalformedException malEx)
            {
                HandleErrors(context, "Malformed Update Error", updateText, malEx, (int)HttpStatusCode.BadRequest);
            }
            catch (SparqlUpdateException updateEx)
            {
                HandleErrors(context, "Update Error", updateText, updateEx);
            }
            catch (RdfException rdfEx)
            {
                HandleErrors(context, "RDF Error", updateText, rdfEx);
            }
            catch (NotSupportedException notSupEx)
            {
                HandleErrors(context, "HTTP Request Error", null, notSupEx, (int)HttpStatusCode.MethodNotAllowed);
            }
            catch (ArgumentException argEx)
            {
                HandleErrors(context, "HTTP Request Error", null, argEx, (int)HttpStatusCode.BadRequest);
            }
            catch (Exception ex)
            {
                HandleErrors(context, "Error", updateText, ex);
            }
        }
Пример #6
0
 /// <summary>
 /// Selects the Writer to use for sending the Graph to the Client
 /// </summary>
 /// <param name="definition">Selected MIME Type Definition</param>
 /// <returns></returns>
 /// <remarks>
 /// <para>
 /// Implementations may override this if they wish to substitute in an alternative writer for certain MIME types (e.g. as done by the <see cref="SchemaGraphHandler">SchemaGraphHandler</see>)
 /// </para>
 /// </remarks>
 protected virtual IRdfWriter SelectWriter(MimeTypeDefinition definition)
 {
     return(definition.GetRdfWriter());
 }
Пример #7
0
        /// <summary>
        /// Processes SPARQL Update requests
        /// </summary>
        /// <param name="context">HTTP Context</param>
        public void ProcessRequest(HttpContext context)
        {
            this._config = this.LoadConfig(context);

            //Add our Standard Headers
            HandlerHelper.AddStandardHeaders(context, this._config);

            if (context.Request.HttpMethod.Equals("OPTIONS"))
            {
                //OPTIONS requests always result in the Service Description document
                IGraph svcDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, new Uri(context.Request.Url.AbsoluteUri));
                HandlerHelper.SendToClient(context, svcDescrip, this._config);
                return;
            }

            //See if there has been an update submitted
            String updateText = context.Request.QueryString["update"];

            if (updateText == null || updateText.Equals(String.Empty))
            {
                updateText = context.Request.Form["update"];
            }

            //If no Update sent either show Update Form or give a HTTP 400 response
            if (updateText == null || updateText.Equals(String.Empty))
            {
                //If there is no Update we may return the SPARQL Service Description where appropriate
                try
                {
                    //If we might show the Update Form only show the Description if the selected writer is
                    //not a HTML writer
                    MimeTypeDefinition definition = MimeTypesHelper.GetDefinitions(HandlerHelper.GetAcceptTypes(context)).FirstOrDefault(d => d.CanWriteRdf);
                    if (definition != null)
                    {
                        IRdfWriter writer = definition.GetRdfWriter();
                        if (!this._config.ShowUpdateForm || !(writer is IHtmlWriter))
                        {
                            //If not a HTML Writer selected OR not showing Update Form then show the Service Description Graph
                            //unless an error occurs creating it
                            IGraph serviceDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, new Uri(context.Request.Url.AbsoluteUri));
                            context.Response.ContentType     = definition.CanonicalMimeType;
                            context.Response.ContentEncoding = definition.Encoding;
                            writer.Save(serviceDescrip, new StreamWriter(context.Response.OutputStream, definition.Encoding));
                            return;
                        }
                    }
                }
                catch
                {
                    //Ignore Exceptions - we'll just show the Query Form or return a 400 Bad Request instead
                }

                //If a Writer can't be selected then we'll either show the Update Form or return a 400 Bad Request
                if (this._config.ShowUpdateForm)
                {
                    this.ShowUpdateForm(context);
                }
                else
                {
                    context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
                }
                return;
            }

            try
            {
                //Now we're going to parse the Updates
                SparqlUpdateParser parser = new SparqlUpdateParser();
                parser.ExpressionFactories = this._config.ExpressionFactories;
                SparqlUpdateCommandSet commands = parser.ParseFromString(updateText);

                //Check whether we need to use authentication
                //If there are no user groups then no authentication is in use so we default to authenticated with no per-action authentication needed
                bool isAuth = true, requireActionAuth = false;
                if (this._config.UserGroups.Any())
                {
                    //If we have user
                    isAuth            = HandlerHelper.IsAuthenticated(context, this._config.UserGroups);
                    requireActionAuth = true;
                }
                if (!isAuth)
                {
                    return;
                }

                //First check actions to see whether they are all permissible
                foreach (SparqlUpdateCommand cmd in commands.Commands)
                {
                    //Authenticate each action
                    bool actionAuth = true;
                    if (requireActionAuth)
                    {
                        actionAuth = HandlerHelper.IsAuthenticated(context, this._config.UserGroups, this.GetPermissionAction(cmd));
                    }
                    if (!actionAuth)
                    {
                        throw new SparqlUpdateException("You are not authorised to perform the " + this.GetPermissionAction(cmd) + " action");
                    }
                }

                //Then assuming we got here this means all our actions are permitted so now we can process the updates
                this.ProcessUpdates(commands);

                //Flush outstanding changes
                this._config.Processor.Flush();

                //Update the Cache as the request may have changed the endpoint
                this.UpdateConfig(context);
            }
            catch (RdfParseException parseEx)
            {
                HandleErrors(context, "Parsing Error", updateText, parseEx);
            }
            catch (SparqlUpdateException updateEx)
            {
                HandleErrors(context, "Update Error", updateText, updateEx);
            }
            catch (RdfException rdfEx)
            {
                HandleErrors(context, "RDF Error", updateText, rdfEx);
            }
            catch (Exception ex)
            {
                HandleErrors(context, "Error", updateText, ex);
            }
        }
Пример #8
0
        /// <summary>
        /// Processes SPARQL Update requests
        /// </summary>
        /// <param name="context">HTTP Context</param>
        public void ProcessRequest(HttpContext context)
        {
            this._config = this.LoadConfig(context);

            //Add our Standard Headers
            HandlerHelper.AddStandardHeaders(context, this._config);

            if (context.Request.HttpMethod.Equals("OPTIONS"))
            {
                //OPTIONS requests always result in the Service Description document
                IGraph svcDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, UriFactory.Create(context.Request.Url.AbsoluteUri));
                HandlerHelper.SendToClient(context, svcDescrip, this._config);
                return;
            }

            //See if there has been an update submitted
            String updateText = null;

            if (context.Request.ContentType != null)
            {
                if (context.Request.ContentType.Equals(MimeTypesHelper.WWWFormURLEncoded))
                {
                    updateText = context.Request.Form["update"];
                }
                else if (context.Request.ContentType.Equals(MimeTypesHelper.SparqlUpdate))
                {
                    updateText = new StreamReader(context.Request.InputStream).ReadToEnd();
                }
            }
            else
            {
                updateText = context.Request.Form["update"];
            }

            //If no Update sent either show Update Form or give a HTTP 400 response
            if (updateText == null || updateText.Equals(String.Empty))
            {
                //If there is no Update we may return the SPARQL Service Description where appropriate
                try
                {
                    //If we might show the Update Form only show the Description if the selected writer is
                    //not a HTML writer
                    MimeTypeDefinition definition = MimeTypesHelper.GetDefinitions(HandlerHelper.GetAcceptTypes(context)).FirstOrDefault(d => d.CanWriteRdf);
                    if (definition != null)
                    {
                        IRdfWriter writer = definition.GetRdfWriter();
                        if (!this._config.ShowUpdateForm || !(writer is IHtmlWriter))
                        {
                            //If not a HTML Writer selected OR not showing Update Form then show the Service Description Graph
                            //unless an error occurs creating it
                            IGraph serviceDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, UriFactory.Create(context.Request.Url.AbsoluteUri));
                            context.Response.ContentType     = definition.CanonicalMimeType;
                            context.Response.ContentEncoding = definition.Encoding;
                            writer.Save(serviceDescrip, new StreamWriter(context.Response.OutputStream, definition.Encoding));
                            return;
                        }
                    }
                }
                catch
                {
                    //Ignore Exceptions - we'll just show the Query Form or return a 400 Bad Request instead
                }

                //If a Writer can't be selected then we'll either show the Update Form or return a 400 Bad Request
                if (this._config.ShowUpdateForm)
                {
                    this.ShowUpdateForm(context);
                }
                else
                {
                    context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
                }
                return;
            }

            //Get Other options associated with this update
            List <String> userDefaultGraphs = new List <String>();
            List <String> userNamedGraphs   = new List <String>();

            //Get the USING URIs (if any)
            if (context.Request.QueryString["using-graph-uri"] != null)
            {
                userDefaultGraphs.AddRange(context.Request.QueryString.GetValues("using-graph-uri"));
            }
            else if (context.Request.Form["using-graph-uri"] != null)
            {
                userDefaultGraphs.AddRange(context.Request.Form.GetValues("using-graph-uri"));
            }
            //Get the USING NAMED URIs (if any)
            if (context.Request.QueryString["using-named-graph-uri"] != null)
            {
                userNamedGraphs.AddRange(context.Request.QueryString.GetValues("using-named-graph-uri"));
            }
            else if (context.Request.Form["using-named-graph-uri"] != null)
            {
                userNamedGraphs.AddRange(context.Request.Form.GetValues("using-named-graph-uri"));
            }

            try
            {
                //Now we're going to parse the Updates
                SparqlUpdateParser parser = new SparqlUpdateParser();
                parser.ExpressionFactories = this._config.ExpressionFactories;
                SparqlUpdateCommandSet commands = parser.ParseFromString(updateText);

                //Check whether we need to use authentication
                //If there are no user groups then no authentication is in use so we default to authenticated with no per-action authentication needed
                bool isAuth = true, requireActionAuth = false;
                if (this._config.UserGroups.Any())
                {
                    //If we have user
                    isAuth            = HandlerHelper.IsAuthenticated(context, this._config.UserGroups);
                    requireActionAuth = true;
                }
                if (!isAuth)
                {
                    return;
                }

                //First check actions to see whether they are all permissible and apply USING/USING NAMED parameters
                foreach (SparqlUpdateCommand cmd in commands.Commands)
                {
                    //Authenticate each action
                    bool actionAuth = true;
                    if (requireActionAuth)
                    {
                        actionAuth = HandlerHelper.IsAuthenticated(context, this._config.UserGroups, this.GetPermissionAction(cmd));
                    }
                    if (!actionAuth)
                    {
                        throw new SparqlUpdatePermissionException("You are not authorised to perform the " + this.GetPermissionAction(cmd) + " action");
                    }

                    //Check whether we need to (and are permitted to) apply USING/USING NAMED parameters
                    if (userDefaultGraphs.Count > 0 || userNamedGraphs.Count > 0)
                    {
                        BaseModificationCommand modify = cmd as BaseModificationCommand;
                        if (modify != null)
                        {
                            if (modify.GraphUri != null || modify.UsingUris.Any() || modify.UsingNamedUris.Any())
                            {
                                //Invalid if a command already has a WITH/USING/USING NAMED
                                throw new SparqlUpdateMalformedException("A command in your update request contains a WITH/USING/USING NAMED clause but you have also specified one/both of the using-graph-uri or using-named-graph-uri parameters which is not permitted by the SPARQL Protocol");
                            }
                            else
                            {
                                //Otherwise go ahead and apply
                                userDefaultGraphs.ForEach(u => modify.AddUsingUri(UriFactory.Create(u)));
                                userNamedGraphs.ForEach(u => modify.AddUsingNamedUri(UriFactory.Create(u)));
                            }
                        }
                    }
                }

                //Then assuming we got here this means all our actions are permitted so now we can process the updates
                this.ProcessUpdates(commands);

                //Flush outstanding changes
                this._config.Processor.Flush();

                //Update the Cache as the request may have changed the endpoint
                this.UpdateConfig(context);
            }
            catch (RdfParseException parseEx)
            {
                HandleErrors(context, "Parsing Error", updateText, parseEx, (int)HttpStatusCode.BadRequest);
            }
            catch (SparqlUpdatePermissionException permEx)
            {
                HandleErrors(context, "Permissions Error", updateText, permEx, (int)HttpStatusCode.Forbidden);
            }
            catch (SparqlUpdateMalformedException malEx)
            {
                HandleErrors(context, "Malformed Update Error", updateText, malEx, (int)HttpStatusCode.BadRequest);
            }
            catch (SparqlUpdateException updateEx)
            {
                HandleErrors(context, "Update Error", updateText, updateEx);
            }
            catch (RdfException rdfEx)
            {
                HandleErrors(context, "RDF Error", updateText, rdfEx);
            }
            catch (Exception ex)
            {
                HandleErrors(context, "Error", updateText, ex);
            }
        }
Пример #9
0
        /// <summary>
        /// Processes a SPARQL Query Request
        /// </summary>
        /// <param name="context">HTTP Context</param>
        public void ProcessRequest(HttpContext context)
        {
            this._config = this.LoadConfig(context);

            //Add our Standard Headers
            HandlerHelper.AddStandardHeaders(context, this._config);

            if (context.Request.HttpMethod.Equals("OPTIONS"))
            {
                //OPTIONS requests always result in the Service Description document
                IGraph svcDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, new Uri(context.Request.Url.AbsoluteUri));
                HandlerHelper.SendToClient(context, svcDescrip, this._config);
                return;
            }

            //See if there has been an query submitted
            String queryText = context.Request.QueryString["query"];

            if (queryText == null || queryText.Equals(String.Empty))
            {
                queryText = context.Request.Form["query"];
            }

            //If no Query sent either show Query Form or give a HTTP 400 response
            if (queryText == null || queryText.Equals(String.Empty))
            {
                //If there is no Query we may return the SPARQL Service Description where appropriate
                try
                {
                    //If we might show the Query Form only show the Description if the selected writer is
                    //not a HTML writer
                    MimeTypeDefinition definition = MimeTypesHelper.GetDefinitions(HandlerHelper.GetAcceptTypes(context)).FirstOrDefault(d => d.CanWriteRdf);
                    if (definition != null)
                    {
                        IRdfWriter writer = definition.GetRdfWriter();
                        if (!this._config.ShowQueryForm || !(writer is IHtmlWriter))
                        {
                            //If not a HTML Writer selected OR not showing Query Form then show the Service Description Graph
                            //unless an error occurs creating it
                            IGraph serviceDescrip = SparqlServiceDescriber.GetServiceDescription(context, this._config, new Uri(context.Request.Url.AbsoluteUri));
                            context.Response.ContentType     = definition.CanonicalMimeType;
                            context.Response.ContentEncoding = definition.Encoding;
                            writer.Save(serviceDescrip, new StreamWriter(context.Response.OutputStream, definition.Encoding));
                            return;
                        }
                    }
                }
                catch
                {
                    //Ignore Exceptions - we'll just show the Query Form or return a 400 Bad Request instead
                }

                //If a Writer can't be selected then we'll either show the Query Form or return a 400 Bad Request
                if (this._config.ShowQueryForm)
                {
                    this.ShowQueryForm(context);
                }
                else
                {
                    context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
                }
                return;
            }

            //Get Other options associated with this query
            List <String> userDefaultGraphs = new List <String>();
            List <String> userNamedGraphs   = new List <String>();
            long          timeout           = 0;
            bool          partialResults    = this._config.DefaultPartialResults;

            //Get the Default Graph URIs (if any)
            if (context.Request.QueryString["default-graph-uri"] != null)
            {
                userDefaultGraphs.AddRange(context.Request.QueryString.GetValues("default-graph-uri"));
            }
            else if (context.Request.Form["default-graph-uri"] != null)
            {
                userDefaultGraphs.AddRange(context.Request.Form.GetValues("default-graph-uri"));
            }
            //Get the Named Graph URIs (if any)
            if (context.Request.QueryString["named-graph-uri"] != null)
            {
                userNamedGraphs.AddRange(context.Request.QueryString.GetValues("named-graph-uri"));
            }
            else if (context.Request.Form["named-graph-uri"] != null)
            {
                userNamedGraphs.AddRange(context.Request.Form.GetValues("named-graph-uri"));
            }

            //Get Timeout setting (if any)
            if (context.Request.QueryString["timeout"] != null)
            {
                if (!Int64.TryParse(context.Request.QueryString["timeout"], out timeout))
                {
                    timeout = this._config.DefaultTimeout;
                }
            }
            else if (context.Request.Form["timeout"] != null)
            {
                if (!Int64.TryParse(context.Request.Form["timeout"], out timeout))
                {
                    timeout = this._config.DefaultTimeout;
                }
            }
            //Get Partial Results Setting (if any);
            if (context.Request.QueryString["partialResults"] != null)
            {
                if (!Boolean.TryParse(context.Request.QueryString["partialResults"], out partialResults))
                {
                    partialResults = this._config.DefaultPartialResults;
                }
            }
            else if (context.Request.Form["partialResults"] != null)
            {
                if (!Boolean.TryParse(context.Request.Form["partialResults"], out partialResults))
                {
                    partialResults = this._config.DefaultPartialResults;
                }
            }

            try
            {
                //Now we're going to parse the Query
                SparqlQueryParser parser = new SparqlQueryParser(this._config.Syntax);
                parser.ExpressionFactories = this._config.ExpressionFactories;
                parser.QueryOptimiser      = this._config.QueryOptimiser;
                SparqlQuery query = parser.ParseFromString(queryText);
                query.AlgebraOptimisers = this._config.AlgebraOptimisers;

                //Check whether we need to use authentication
                //If there are no user groups then no authentication is in use so we default to authenticated with no per-action authentication needed
                bool isAuth = true, requireActionAuth = false;
                if (this._config.UserGroups.Any())
                {
                    //If we have user
                    isAuth            = HandlerHelper.IsAuthenticated(context, this._config.UserGroups);
                    requireActionAuth = true;
                }
                if (!isAuth)
                {
                    return;
                }

                //Is this user allowed to make this kind of query?
                if (requireActionAuth)
                {
                    HandlerHelper.IsAuthenticated(context, this._config.UserGroups, this.GetPermissionAction(query));
                }

                //Set the Default Graph URIs (if any)
                if (userDefaultGraphs.Count > 0)
                {
                    //Default Graph Uri specified by default-graph-uri parameter or Web.config settings
                    foreach (String userDefaultGraph in userDefaultGraphs)
                    {
                        if (!userDefaultGraph.Equals(String.Empty))
                        {
                            query.AddDefaultGraph(new Uri(userDefaultGraph));
                        }
                    }
                }
                else if (!this._config.DefaultGraphURI.Equals(String.Empty))
                {
                    //Only applies if the Query doesn't specify any Default Graph
                    if (!query.DefaultGraphs.Any())
                    {
                        query.AddDefaultGraph(new Uri(this._config.DefaultGraphURI));
                    }
                }

                //Set the Named Graph URIs (if any)
                if (userNamedGraphs.Count > 0)
                {
                    foreach (String userNamedGraph in userNamedGraphs)
                    {
                        if (!userNamedGraph.Equals(String.Empty))
                        {
                            query.AddNamedGraph(new Uri(userNamedGraph));
                        }
                    }
                }

                //Set Timeout setting
                if (timeout > 0)
                {
                    query.Timeout = timeout;
                }
                else
                {
                    query.Timeout = this._config.DefaultTimeout;
                }

                //Set Partial Results Setting
                query.PartialResultsOnTimeout = partialResults;

                //Set Describe Algorithm
                query.Describer = this._config.DescribeAlgorithm;

                //Now we can finally make the query and return the results
                Object result = this.ProcessQuery(query);
                this.ProcessResults(context, result);

                //Update the Cache as the request may have changed the endpoint
                this.UpdateConfig(context);
            }
            catch (RdfParseException parseEx)
            {
                HandleErrors(context, "Parsing Error", queryText, parseEx, (int)HttpStatusCode.BadRequest);
            }
            catch (RdfQueryTimeoutException timeoutEx)
            {
                HandleErrors(context, "Query Timeout Error", queryText, timeoutEx);
            }
            catch (RdfQueryException queryEx)
            {
                HandleErrors(context, "Update Error", queryText, queryEx);
            }
            catch (RdfWriterSelectionException writerSelEx)
            {
                HandleErrors(context, "Output Selection Error", queryText, writerSelEx, (int)HttpStatusCode.NotAcceptable);
            }
            catch (RdfException rdfEx)
            {
                HandleErrors(context, "RDF Error", queryText, rdfEx);
            }
            catch (Exception ex)
            {
                HandleErrors(context, "Error", queryText, ex);
            }
        }
Пример #10
0
        /// <summary>
        /// Processes a SPARQL Query Request
        /// </summary>
        /// <param name="context">HTTP Context</param>
        public void ProcessRequest(HttpContext context)
        {
            this._config = this.LoadConfig(context);
            WebContext webContext = new WebContext(context);

            //Add our Standard Headers
            HandlerHelper.AddStandardHeaders(webContext, this._config);

            //Options we need to determine based on the HTTP Method used
            String[]      queries;
            String        queryText         = null;
            List <String> userDefaultGraphs = new List <String>();
            List <String> userNamedGraphs   = new List <String>();

            try
            {
                //Decide what to do based on the HTTP Method
                switch (context.Request.HttpMethod.ToUpper())
                {
                case "OPTIONS":
                    //OPTIONS requests always result in the Service Description document
                    IGraph svcDescrip = SparqlServiceDescriber.GetServiceDescription(this._config, UriFactory.Create(context.Request.Url.AbsoluteUri));
                    HandlerHelper.SendToClient(webContext, svcDescrip, this._config);
                    return;

                case "HEAD":
                    //Just return from a HEAD request
                    return;

                case "GET":
                    //GET expects a query parameter in the querystring
                    queries = context.Request.QueryString.GetValues("query");
                    if (queries != null)
                    {
                        if (queries.Length > 1)
                        {
                            throw new ArgumentException("The query parameter was specified multiple times in the querystring");
                        }
                        queryText = queries.Length == 1 ? queries[0] : null;
                    }

                    //If no Query sent either show Query Form or give a HTTP 400 response
                    if (String.IsNullOrEmpty(queryText))
                    {
                        //If there is no Query we may return the SPARQL Service Description where appropriate
                        try
                        {
                            //If we might show the Query Form only show the Description if the selected writer is
                            //not a HTML writer
                            MimeTypeDefinition definition = MimeTypesHelper.GetDefinitions(HandlerHelper.GetAcceptTypes(webContext)).FirstOrDefault(d => d.CanWriteRdf);
                            if (definition != null)
                            {
                                IRdfWriter writer = definition.GetRdfWriter();
                                if (!this._config.ShowQueryForm || !(writer is IHtmlWriter))
                                {
                                    //If not a HTML Writer selected OR not showing Query Form then show the Service Description Graph
                                    //unless an error occurs creating it
                                    IGraph serviceDescrip = SparqlServiceDescriber.GetServiceDescription(this._config, UriFactory.Create(context.Request.Url.AbsoluteUri));
                                    context.Response.ContentType     = definition.CanonicalMimeType;
                                    context.Response.ContentEncoding = definition.Encoding;
                                    writer.Save(serviceDescrip, new StreamWriter(context.Response.OutputStream, definition.Encoding));
                                    return;
                                }
                            }
                        }
                        catch
                        {
                            //Ignore Exceptions - we'll just show the Query Form or return a 400 Bad Request instead
                        }

                        //Otherwise we'll either show the Query Form or return a 400 Bad Request
                        if (this._config.ShowQueryForm)
                        {
                            this.ShowQueryForm(context);
                        }
                        else
                        {
                            throw new ArgumentException("Missing required query parameter");
                        }
                        return;
                    }

                    //Get the Default Graph URIs (if any)
                    if (context.Request.QueryString["default-graph-uri"] != null)
                    {
                        userDefaultGraphs.AddRange(context.Request.QueryString.GetValues("default-graph-uri"));
                    }
                    //Get the Named Graph URIs (if any)
                    if (context.Request.QueryString["named-graph-uri"] != null)
                    {
                        userNamedGraphs.AddRange(context.Request.QueryString.GetValues("named-graph-uri"));
                    }
                    break;

                case "POST":
                    //POST requires a valid content type
                    if (context.Request.ContentType != null)
                    {
                        MimeTypeSelector contentType = MimeTypeSelector.Create(context.Request.ContentType, 0);
                        if (contentType.Type.Equals(MimeTypesHelper.WWWFormURLEncoded))
                        {
                            //Form URL Encoded was declared type so expect a query parameter in the Form parameters
                            queries = context.Request.Form.GetValues("query");
                            if (queries == null)
                            {
                                throw new ArgumentException("Required query parameter in POST body was missing");
                            }
                            if (queries.Length == 0)
                            {
                                throw new ArgumentException("Required query parameter in POST body was missing");
                            }
                            if (queries.Length > 1)
                            {
                                throw new ArgumentException("The query parameter was specified multiple times in the POST body");
                            }
                            queryText = queries[0];

                            //For Form URL Encoded the Default/Named Graphs may be specified by Form parameters
                            //Get the Default Graph URIs (if any)
                            if (context.Request.Form["default-graph-uri"] != null)
                            {
                                userDefaultGraphs.AddRange(context.Request.Form.GetValues("default-graph-uri"));
                            }
                            //Get the Named Graph URIs (if any)
                            if (context.Request.Form["named-graph-uri"] != null)
                            {
                                userNamedGraphs.AddRange(context.Request.Form.GetValues("named-graph-uri"));
                            }

                            break;
                        }
                        else if (contentType.Type.Equals(MimeTypesHelper.SparqlQuery))
                        {
                            //application/sparql-query was declared type so expect utf-8 charset (if present)
                            if (contentType.Charset != null && !contentType.Charset.ToLower().Equals(MimeTypesHelper.CharsetUtf8))
                            {
                                throw new ArgumentException("HTTP POST request was received with a " + MimeTypesHelper.SparqlQuery + " Content-Type but a non UTF-8 charset parameter");
                            }

                            //Read the query from the request body
                            using (StreamReader reader = new StreamReader(context.Request.InputStream))
                            {
                                queryText = reader.ReadToEnd();
                                reader.Close();
                            }

                            //For application/sparql-query the Default/Named Graphs may be specified by querystring parameters
                            //Get the Default Graph URIs (if any)
                            if (context.Request.QueryString["default-graph-uri"] != null)
                            {
                                userDefaultGraphs.AddRange(context.Request.QueryString.GetValues("default-graph-uri"));
                            }
                            //Get the Named Graph URIs (if any)
                            if (context.Request.QueryString["named-graph-uri"] != null)
                            {
                                userNamedGraphs.AddRange(context.Request.QueryString.GetValues("named-graph-uri"));
                            }

                            break;
                        }
                        else
                        {
                            throw new ArgumentException("HTTP POST made to SPARQL query endpoint had an invalid Content-Type header, only " + MimeTypesHelper.WWWFormURLEncoded + " and " + MimeTypesHelper.SparqlQuery + " are acceptable");
                        }
                    }
                    throw new ArgumentException("HTTP POST made to SPARQL Query endpoint was missing the required Content-Type header");

                default:
                    throw new NotSupportedException("HTTP " + context.Request.HttpMethod.ToUpper() + " is not supported by a SPARQL Query endpoint");
                }

                //Get non-standard options associated with the query
                long timeout        = 0;
                bool partialResults = this._config.DefaultPartialResults;

                //Get Timeout setting (if any)
                if (context.Request.QueryString["timeout"] != null)
                {
                    if (!Int64.TryParse(context.Request.QueryString["timeout"], out timeout))
                    {
                        timeout = this._config.DefaultTimeout;
                    }
                }
                else if (context.Request.Form["timeout"] != null)
                {
                    if (!Int64.TryParse(context.Request.Form["timeout"], out timeout))
                    {
                        timeout = this._config.DefaultTimeout;
                    }
                }
                //Get Partial Results Setting (if any);
                if (context.Request.QueryString["partialResults"] != null)
                {
                    if (!Boolean.TryParse(context.Request.QueryString["partialResults"], out partialResults))
                    {
                        partialResults = this._config.DefaultPartialResults;
                    }
                }
                else if (context.Request.Form["partialResults"] != null)
                {
                    if (!Boolean.TryParse(context.Request.Form["partialResults"], out partialResults))
                    {
                        partialResults = this._config.DefaultPartialResults;
                    }
                }

                //Now we're going to parse the Query
                SparqlQueryParser parser = new SparqlQueryParser(this._config.Syntax);
                parser.DefaultBaseUri      = context.Request.Url;
                parser.ExpressionFactories = this._config.ExpressionFactories;
                parser.QueryOptimiser      = this._config.QueryOptimiser;
                SparqlQuery query = parser.ParseFromString(queryText);
                query.AlgebraOptimisers         = this._config.AlgebraOptimisers;
                query.PropertyFunctionFactories = this._config.PropertyFunctionFactories;

                //Check whether we need to use authentication
                //If there are no user groups then no authentication is in use so we default to authenticated with no per-action authentication needed
                bool isAuth = true, requireActionAuth = false;
                if (this._config.UserGroups.Any())
                {
                    //If we have user
                    isAuth            = HandlerHelper.IsAuthenticated(webContext, this._config.UserGroups);
                    requireActionAuth = true;
                }
                if (!isAuth)
                {
                    return;
                }

                //Is this user allowed to make this kind of query?
                if (requireActionAuth)
                {
                    HandlerHelper.IsAuthenticated(webContext, this._config.UserGroups, this.GetPermissionAction(query));
                }

                //Clear query dataset if there is a protocol defined one
                userDefaultGraphs.RemoveAll(g => String.IsNullOrEmpty(g));
                userNamedGraphs.RemoveAll(g => String.IsNullOrEmpty(g));
                bool isProtocolDataset = false;
                if (userDefaultGraphs.Count > 0 || userNamedGraphs.Count > 0)
                {
                    query.ClearDefaultGraphs();
                    query.ClearNamedGraphs();
                    isProtocolDataset = true;
                }

                //Set the Default Graph URIs (if any)
                if (isProtocolDataset)
                {
                    foreach (String userDefaultGraph in userDefaultGraphs)
                    {
                        query.AddDefaultGraph(UriFactory.Create(userDefaultGraph));
                    }
                }
                else if (!this._config.DefaultGraphURI.Equals(String.Empty))
                {
                    //Only applies if the Query doesn't specify any Default Graph and there wasn't a protocol defined
                    //dataset present
                    if (!query.DefaultGraphs.Any())
                    {
                        query.AddDefaultGraph(UriFactory.Create(this._config.DefaultGraphURI));
                    }
                }

                //Set the Named Graph URIs (if any)
                if (isProtocolDataset)
                {
                    query.ClearNamedGraphs();
                    foreach (String userNamedGraph in userNamedGraphs)
                    {
                        query.AddNamedGraph(UriFactory.Create(userNamedGraph));
                    }
                }

                //Set Timeout setting
                if (timeout > 0)
                {
                    query.Timeout = timeout;
                }
                else
                {
                    query.Timeout = this._config.DefaultTimeout;
                }

                //Set Partial Results Setting
                query.PartialResultsOnTimeout = partialResults;

                //Set Describe Algorithm
                query.Describer = this._config.DescribeAlgorithm;

                //Now we can finally make the query and return the results
                Object result = this.ProcessQuery(query);
                this.ProcessResults(context, result);

                //Update the Cache as the request may have changed the endpoint
                this.UpdateConfig(context);
            }
            catch (RdfParseException parseEx)
            {
                HandleErrors(context, "Parsing Error", queryText, parseEx, (int)HttpStatusCode.BadRequest);
            }
            catch (RdfQueryTimeoutException timeoutEx)
            {
                HandleErrors(context, "Query Timeout Error", queryText, timeoutEx);
            }
            catch (RdfQueryException queryEx)
            {
                HandleErrors(context, "Update Error", queryText, queryEx);
            }
            catch (RdfWriterSelectionException writerSelEx)
            {
                HandleErrors(context, "Output Selection Error", queryText, writerSelEx, (int)HttpStatusCode.NotAcceptable);
            }
            catch (RdfException rdfEx)
            {
                HandleErrors(context, "RDF Error", queryText, rdfEx);
            }
            catch (NotSupportedException notSupEx)
            {
                HandleErrors(context, "HTTP Request Error", null, notSupEx, (int)HttpStatusCode.MethodNotAllowed);
            }
            catch (ArgumentException argEx)
            {
                HandleErrors(context, "HTTP Request Error", null, argEx, (int)HttpStatusCode.BadRequest);
            }
            catch (Exception ex)
            {
                HandleErrors(context, "Error", queryText, ex);
            }
        }
Пример #11
0
        static void DoProtocol(Dictionary <String, String> arguments)
        {
            String method;
            SparqlHttpProtocolConnector endpoint;
            bool verbose = arguments.ContainsKey("verbose") || arguments.ContainsKey("v");

            if (verbose)
            {
                Options.HttpDebugging = true;
            }
            Options.UriLoaderCaching = !arguments.ContainsKey("nocache");
            String dataFile;

            //First Argument must be HTTP Method
            if (arguments.ContainsKey("$1") && !arguments["$1"].Equals(String.Empty))
            {
                method = arguments["$1"].ToUpper();
            }
            else
            {
                Console.Error.WriteLine("soh: Error: First argument must be one of head, get, put or post - type soh --help for details");
                Environment.Exit(-1);
                return;
            }

            try
            {
                if (arguments.ContainsKey("$2") && !arguments["$2"].Equals(String.Empty))
                {
                    endpoint = new SparqlHttpProtocolConnector(new Uri(arguments["$2"]));
                }
                else
                {
                    Console.Error.WriteLine("soh: Error: Second argument is required and must be the Dataset URI");
                    Environment.Exit(-1);
                    return;
                }
            }
            catch (UriFormatException uriEx)
            {
                Console.Error.WriteLine("soh: Error: Malformed SPARQL Endpoint URI");
                Console.Error.WriteLine(uriEx.Message);
                Environment.Exit(-1);
                return;
            }
            if (verbose)
            {
                Console.Error.WriteLine("soh: Connection to SPARQL Uniform HTTP Protocol endpoint created OK");
            }

            Uri graphUri;

            try
            {
                if (arguments.ContainsKey("$3") && !arguments["$3"].Equals(String.Empty))
                {
                    if (arguments["$3"].Equals("default"))
                    {
                        graphUri = null;
                        if (verbose)
                        {
                            Console.Error.WriteLine("soh: Graph URI for Protocol request is 'default' (indicates the default unnamed graph)");
                        }
                    }
                    else
                    {
                        graphUri = new Uri(arguments["$3"]);
                        if (verbose)
                        {
                            Console.Error.WriteLine("soh: Graph URI for Protocol request is '" + graphUri.ToString() + "'");
                        }
                    }
                }
                else
                {
                    Console.Error.WriteLine("soh: Error: Third argument is required and must be the Graph URI or default to indicate the default unnamed Graph");
                    Environment.Exit(-1);
                    return;
                }
            }
            catch (UriFormatException uriEx)
            {
                Console.Error.WriteLine("soh: Error: Malformed Graph URI");
                Console.Error.WriteLine(uriEx.Message);
                Environment.Exit(-1);
                return;
            }

            try
            {
                switch (method)
                {
                case "GET":
                    if (arguments.ContainsKey("$4"))
                    {
                        Console.Error.WriteLine("soh: Error: Optional file argument for protocol mode is not permitted with the get method");
                        Environment.Exit(-1);
                        return;
                    }

                    if (verbose)
                    {
                        Console.Error.WriteLine("soh: Making a GET request to the Protocol endpoint");
                    }
                    Graph g = new Graph();
                    endpoint.LoadGraph(g, graphUri);
                    if (verbose)
                    {
                        Console.Error.WriteLine("soh: Received a Graph with " + g.Triples.Count + " Triples");
                    }

                    //Use users choice of output format otherwise RDF/XML
                    MimeTypeDefinition definition = null;
                    if (arguments.ContainsKey("accept"))
                    {
                        definition = MimeTypesHelper.GetDefinitions(arguments["accept"]).FirstOrDefault(d => d.CanWriteRdf);
                    }

                    if (definition != null)
                    {
                        Console.OutputEncoding = definition.Encoding;
                        IRdfWriter writer = definition.GetRdfWriter();
                        writer.Save(g, new StreamWriter(Console.OpenStandardOutput(), definition.Encoding));
                    }
                    else
                    {
                        if (arguments.ContainsKey("accept") && verbose)
                        {
                            Console.Error.WriteLine("soh: Warning: You wanted output in format '" + arguments["accept"] + "' but dotNetRDF does not support this format so RDF/XML will be returned instead");
                        }

                        RdfXmlWriter rdfXmlWriter = new RdfXmlWriter();
                        rdfXmlWriter.Save(g, new StreamWriter(Console.OpenStandardOutput(), Encoding.UTF8));
                    }

                    break;

                case "HEAD":
                    if (arguments.ContainsKey("$4"))
                    {
                        Console.Error.WriteLine("soh: Error: Optional file argument for protocol mode is not permitted with the head method");
                        Environment.Exit(-1);
                        return;
                    }

                    if (verbose)
                    {
                        Console.Error.WriteLine("soh: Making a HEAD request to the Protocol endpoint");
                    }

                    bool exists = endpoint.HasGraph(graphUri);
                    Console.WriteLine(exists.ToString().ToLower());
                    break;

                case "PUT":
                    //Parse in the Graph to be PUT first
                    if (arguments.ContainsKey("$4") && !arguments["$4"].Equals(String.Empty))
                    {
                        dataFile = arguments["$4"];
                    }
                    else
                    {
                        Console.Error.WriteLine("soh: Error: The file argument for protocol mode is required when using the put method");
                        Environment.Exit(-1);
                        return;
                    }
                    Graph toPut = new Graph();
                    FileLoader.Load(toPut, dataFile);
                    toPut.BaseUri = graphUri;

                    if (verbose)
                    {
                        Console.Error.WriteLine("soh: Graph to be uploaded has " + toPut.Triples.Count + " Triples");
                        Console.Error.WriteLine("soh: Making a PUT request to the Protocol endpoint");
                    }

                    endpoint.SaveGraph(toPut);
                    Console.WriteLine("soh: Graph saved to Protocol endpoint OK");
                    break;

                case "POST":
                    //Parse in the Graph to be PUT first
                    if (arguments.ContainsKey("$4") && !arguments["$4"].Equals(String.Empty))
                    {
                        dataFile = arguments["$4"];
                    }
                    else
                    {
                        Console.Error.WriteLine("soh: Error: The file argument for protocol mode is required when using the post method");
                        Environment.Exit(-1);
                        return;
                    }
                    Graph toPost = new Graph();
                    FileLoader.Load(toPost, dataFile);

                    if (verbose)
                    {
                        Console.Error.WriteLine("soh: Graph to be uploaded has " + toPost.Triples.Count + " Triples");
                        Console.Error.WriteLine("soh: Making a POST request to the Protocol endpoint");
                    }

                    endpoint.UpdateGraph(graphUri, toPost.Triples, null);
                    Console.WriteLine("soh: Graph updated to Protocol endpoint OK");
                    break;

                case "DELETE":
                    if (arguments.ContainsKey("$4"))
                    {
                        Console.Error.WriteLine("soh: Error: Optional file argument for protocol mode is not permitted with the head method");
                        Environment.Exit(-1);
                        return;
                    }
                    endpoint.DeleteGraph(graphUri);
                    Console.WriteLine("soh: Graph deleted from Protocol endpoint OK");
                    break;

                default:
                    Console.Error.WriteLine("soh: Error: " + method + " is not a HTTP Method supported by this tool");
                    Environment.Exit(-1);
                    return;
                }
            }
            catch (Exception ex)
            {
                Console.Error.WriteLine("soh: Error: Error processing HTTP Protocol request");
                Console.Error.WriteLine(ex.Message);
                while (ex.InnerException != null)
                {
                    Console.Error.WriteLine();
                    Console.Error.WriteLine(ex.InnerException.Message);
                    Console.Error.WriteLine(ex.InnerException.StackTrace);
                    ex = ex.InnerException;
                }
                Environment.Exit(-1);
                return;
            }
        }