Example #1
0
        /// <summary>
        /// Saves a Result Set as GZipped output
        /// </summary>
        /// <param name="results">Result Set to save</param>
        /// <param name="output">Writer to save to</param>
        public void Save(SparqlResultSet results, TextWriter output)
        {
            if (results == null)
            {
                throw new RdfOutputException("Cannot write RDF from a null Graph");
            }

            if (output is StreamWriter)
            {
                // Check for inner GZipStream and re-wrap if required
                StreamWriter streamOutput = (StreamWriter)output;
                if (streamOutput.BaseStream is GZipStream)
                {
                    _writer.Save(results, streamOutput);
                }
                else
                {
                    streamOutput = new StreamWriter(new GZipStream(streamOutput.BaseStream, CompressionMode.Compress));
                    _writer.Save(results, streamOutput);
                }
            }
            else
            {
                throw new RdfOutputException("GZipped Output can only be written to StreamWriter instances");
            }
        }
Example #2
0
        /// <summary>
        /// Writes the SPARQL Result Set to a String and returns the Output in your chosen format
        /// </summary>
        /// <param name="results">SPARQL Result Set</param>
        /// <param name="writer">Writer to use to generate the SPARQL Results output</param>
        /// <returns></returns>
        public static String Write(SparqlResultSet results, ISparqlResultsWriter writer)
        {
            System.IO.StringWriter sw = new System.IO.StringWriter();
            writer.Save(results, sw);

            return(sw.ToString());
        }
Example #3
0
 public static void Save(this ISparqlResultsWriter resultsWriter, SparqlResultSet resultSet, string filename)
 {
     using (var output = new StreamWriter(filename))
     {
         resultsWriter.Save(resultSet, output);
     }
 }
        private void EnsureTestData(String file, ISparqlResultsWriter writer)
        {
            if (!File.Exists(file))
            {
                Graph g = new Graph();
                g.LoadFromEmbeddedResource("VDS.RDF.Configuration.configuration.ttl");
                SparqlResultSet results = g.ExecuteQuery("SELECT * WHERE { ?s ?p ?o }") as SparqlResultSet;
                if (results == null) Assert.Fail("Failed to generate sample SPARQL Results");

                writer.Save(results, file);
            }
        }
        private void EnsureTestData(String file, ISparqlResultsWriter writer)
        {
            if (!File.Exists(file))
            {
                Graph g = new Graph();
                g.LoadFromEmbeddedResource("VDS.RDF.Configuration.configuration.ttl");
                g.Retract(g.Triples.Where(t => !t.IsGroundTriple).ToList());
                SparqlResultSet results = g.ExecuteQuery("SELECT * WHERE { ?s ?p ?o }") as SparqlResultSet;
                if (results == null)
                {
                    Assert.True(false, "Failed to generate sample SPARQL Results");
                }

                writer.Save(results, file);
            }
        }
Example #6
0
        private void btnExport_Click(object sender, EventArgs e)
        {
            ExportResultSetOptionsForm exporter = new ExportResultSetOptionsForm();

            if (exporter.ShowDialog() == DialogResult.OK)
            {
                ISparqlResultsWriter writer = exporter.Writer;
                String file = exporter.File;

                try
                {
                    writer.Save(this._results, file);

                    MessageBox.Show("Successfully exported the SPARQL Results to the file '" + file + "'", "SPARQL Results Export Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
                }
                catch (Exception ex)
                {
                    MessageBox.Show("An error occurred attempting to export the SPARQL Results:\n" + ex.Message, "SPARQL Results Export Failed", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
        }
Example #7
0
        public void Setup()
        {
            this._g = new Graph();
            this._g.LoadFromEmbeddedResource("VDS.RDF.Configuration.configuration.ttl");
            this._results = this._g.ExecuteQuery("SELECT * WHERE { ?s ?p ?o }") as SparqlResultSet;

            foreach (MimeTypeDefinition def in MimeTypesHelper.Definitions)
            {
                // Omit CSV since that is a lossy format that does not round trip
                if (def.CanonicalMimeType.Equals("text/csv"))
                {
                    continue;
                }

                if (def.CanWriteRdf && def.CanParseRdf)
                {
                    IRdfWriter writer = def.GetRdfWriter();

                    bool   isManual = !def.CanonicalFileExtension.EndsWith(".gz");
                    String filename = "gzip-tests" + (isManual ? String.Empty : "-auto") + "." + def.CanonicalFileExtension + (isManual ? ".gz" : String.Empty);

                    if (isManual)
                    {
                        using (StreamWriter output = new StreamWriter(new GZipStream(new FileStream(filename, FileMode.Create, FileAccess.Write), CompressionMode.Compress)))
                        {
                            writer.Save(this._g, output);
                            output.Close();
                        }

                        this._manualTestFiles.Add(filename);
                    }
                    else
                    {
                        writer.Save(this._g, filename);

                        this._autoTestFiles.Add(filename);
                    }
                }
                else if (def.CanParseRdfDatasets && def.CanWriteRdfDatasets)
                {
                    IStoreWriter writer = def.GetRdfDatasetWriter();

                    bool   isManual = !def.CanonicalFileExtension.EndsWith(".gz");
                    String filename = "gzip-tests-datasets" + (isManual ? String.Empty : "-auto") + "." + def.CanonicalFileExtension + (isManual ? ".gz" : String.Empty);

                    TripleStore store = new TripleStore();
                    store.Add(this._g);

                    if (isManual)
                    {
                        using (Stream output = new GZipStream(new FileStream(filename, FileMode.Create, FileAccess.Write), CompressionMode.Compress))
                        {
                            writer.Save(store, new StreamWriter(output));
                            output.Close();
                        }

                        this._manualDatasetTestFiles.Add(filename);
                    }
                    else
                    {
                        writer.Save(store, new StreamWriter(new FileStream(filename, FileMode.Create, FileAccess.Write)));

                        this._autoDatasetTestFiles.Add(filename);
                    }
                }
                else if (def.CanParseSparqlResults && def.CanWriteSparqlResults)
                {
                    ISparqlResultsWriter writer = def.GetSparqlResultsWriter();

                    bool   isManual = !def.CanonicalFileExtension.EndsWith(".gz");
                    String filename = "gzip-tests-results" + (isManual ? String.Empty : "-auto") + "." + def.CanonicalFileExtension + (isManual ? ".gz" : String.Empty);

                    if (isManual)
                    {
                        using (StreamWriter output = new StreamWriter(new GZipStream(new FileStream(filename, FileMode.Create, FileAccess.Write), CompressionMode.Compress)))
                        {
                            writer.Save(this._results, output);
                            output.Close();
                        }

                        this._manualResultsTestFiles.Add(filename);
                    }
                    else
                    {
                        writer.Save(this._results, new StreamWriter(filename));

                        this._autoResultsTestFiles.Add(filename);
                    }
                }
            }
        }
Example #8
0
        /// <summary>
        /// Helper function which returns the Results (Graph/Triple Store/SPARQL Results) back to the Client in one of their accepted formats
        /// </summary>
        /// <param name="context">Context of the HTTP Request</param>
        /// <param name="result">Results of the Sparql Query</param>
        /// <param name="config">Handler Configuration</param>
        public static void SendToClient(HttpContext context, Object result, BaseHandlerConfiguration config)
        {
            MimeTypeDefinition definition = null;
            String             ctype      = "text/plain";

            String[] acceptTypes = HandlerHelper.GetAcceptTypes(context);

            //Return the Results
            if (result is SparqlResultSet)
            {
                ISparqlResultsWriter sparqlWriter = null;

                //Try and get a MIME Type Definition using the HTTP Requests Accept Header
                if (acceptTypes != null)
                {
                    definition = MimeTypesHelper.GetDefinitions(acceptTypes).FirstOrDefault(d => d.CanWriteSparqlResults);
                }
                //Try and get the registered Definition for SPARQL Results XML
                if (definition == null)
                {
                    definition = MimeTypesHelper.GetDefinitions(MimeTypesHelper.SparqlXml[0]).FirstOrDefault();
                }
                //If Definition is still null create a temporary definition
                if (definition == null)
                {
                    definition = new MimeTypeDefinition("SPARQL Results XML", MimeTypesHelper.SparqlXml, Enumerable.Empty <String>());
                    definition.SparqlResultsWriterType = typeof(VDS.RDF.Writing.SparqlXmlWriter);
                }

                //Set up the Writer appropriately
                sparqlWriter = definition.GetSparqlResultsWriter();
                context.Response.ContentType = definition.CanonicalMimeType;
                HandlerHelper.ApplyWriterOptions(sparqlWriter, config);

                //Clear any existing Response
                context.Response.Clear();

                //Send Result Set to Client
                context.Response.ContentEncoding = definition.Encoding;
                sparqlWriter.Save((SparqlResultSet)result, new StreamWriter(context.Response.OutputStream, definition.Encoding));
            }
            else if (result is IGraph)
            {
                IRdfWriter rdfWriter = null;

                //Try and get a MIME Type Definition using the HTTP Requests Accept Header
                if (acceptTypes != null)
                {
                    definition = MimeTypesHelper.GetDefinitions(acceptTypes).FirstOrDefault(d => d.CanWriteRdf);
                }
                if (definition == null)
                {
                    //If no appropriate definition then use the GetWriter method instead
                    rdfWriter = MimeTypesHelper.GetWriter(acceptTypes, out ctype);
                }
                else
                {
                    rdfWriter = definition.GetRdfWriter();
                }

                //Setup the writer
                if (definition != null)
                {
                    ctype = definition.CanonicalMimeType;
                }
                context.Response.ContentType = ctype;
                HandlerHelper.ApplyWriterOptions(rdfWriter, config);

                //Clear any existing Response
                context.Response.Clear();

                //Send Graph to Client
                if (definition != null)
                {
                    context.Response.ContentEncoding = definition.Encoding;
                    rdfWriter.Save((IGraph)result, new StreamWriter(context.Response.OutputStream, definition.Encoding));
                }
                else
                {
                    rdfWriter.Save((IGraph)result, new StreamWriter(context.Response.OutputStream));
                }
            }
            else if (result is ITripleStore)
            {
                IStoreWriter storeWriter = null;

                //Try and get a MIME Type Definition using the HTTP Requests Accept Header
                if (acceptTypes != null)
                {
                    definition = MimeTypesHelper.GetDefinitions(acceptTypes).FirstOrDefault(d => d.CanWriteRdfDatasets);
                }
                if (definition == null)
                {
                    //If no appropriate definition then use the GetStoreWriter method instead
                    storeWriter = MimeTypesHelper.GetStoreWriter(acceptTypes, out ctype);
                }
                else
                {
                    storeWriter = definition.GetRdfDatasetWriter();
                }

                //Setup the writer
                if (definition != null)
                {
                    ctype = definition.CanonicalMimeType;
                }
                context.Response.ContentType = ctype;
                HandlerHelper.ApplyWriterOptions(storeWriter, config);

                //Clear any existing Response
                context.Response.Clear();

                //Send Triple Store to Client
                if (definition != null)
                {
                    context.Response.ContentEncoding = definition.Encoding;
                    storeWriter.Save((ITripleStore)result, new VDS.RDF.Storage.Params.StreamParams(context.Response.OutputStream, definition.Encoding));
                }
                else
                {
                    storeWriter.Save((ITripleStore)result, new VDS.RDF.Storage.Params.StreamParams(context.Response.OutputStream));
                }
            }
            else if (result is ISparqlDataset)
            {
                //Wrap in a Triple Store and then call self so the Triple Store writing branch of this if gets called instead
                TripleStore store = new TripleStore(new DatasetGraphCollection((ISparqlDataset)result));
                HandlerHelper.SendToClient(context, store, config);
            }
            else
            {
                throw new RdfOutputException("Unexpected Result Object of Type '" + result.GetType().ToString() + "' returned - unable to write Objects of this Type to the HTTP Response");
            }
        }
Example #9
0
        /// <summary>
        /// Writes the SPARQL Result Set to a String and returns the Output in your chosen format
        /// </summary>
        /// <param name="results">SPARQL Result Set</param>
        /// <param name="writer">Writer to use to generate the SPARQL Results output</param>
        /// <returns></returns>
        public static String Write(SparqlResultSet results, ISparqlResultsWriter writer)
        {
            System.IO.StringWriter sw = new System.IO.StringWriter();
            writer.Save(results, sw);

            return sw.ToString();
        }
Example #10
0
        public BrightstarSparqlResultsType ExecuteSparql(SparqlQuery query, IStore store, TextWriter resultsWriter)
        {
            try
            {
                EnsureValidResultFormat(query);

                var dataset = MakeDataset(store);
                if (_defaultGraphUris != null)
                {
                    dataset.SetDefaultGraph(_defaultGraphUris);
                }

                var queryProcessor = new BrightstarQueryProcessor(store, dataset);
                var queryResult    = queryProcessor.ProcessQuery(query);
                if (queryResult is SparqlResultSet)
                {
                    var sparqlResultSet = (SparqlResultSet)queryResult;
                    ISparqlResultsWriter sparqlResultsWriter = null;
                    if (_sparqlResultsFormat != null)
                    {
                        sparqlResultsWriter =
                            MimeTypesHelper.GetSparqlWriter(new string[] { _sparqlResultsFormat.ToString() });
                    }
                    if (sparqlResultsWriter == null)
                    {
                        throw new NoAcceptableFormatException(typeof(SparqlResultsFormat),
                                                              "No acceptable format provided for writing a SPARQL result set.");
                    }
                    sparqlResultsWriter.Save(sparqlResultSet, resultsWriter);
                    switch (sparqlResultSet.ResultsType)
                    {
                    case SparqlResultsType.Boolean:
                        return(BrightstarSparqlResultsType.Boolean);

                    case SparqlResultsType.VariableBindings:
                        return(BrightstarSparqlResultsType.VariableBindings);

                    default:
                        throw new BrightstarInternalException("Unrecognized SPARQL result type");
                    }
                }
                if (queryResult is IGraph)
                {
                    var g         = (IGraph)queryResult;
                    var rdfWriter = _rdfFormat == null
                                        ? null
                                        : MimeTypesHelper.GetWriter(new string[] { _rdfFormat.ToString() });
                    if (rdfWriter == null)
                    {
                        throw new NoAcceptableFormatException(typeof(RdfFormat),
                                                              "No acceptable format provided for writing an RDF graph result.");
                    }
                    rdfWriter.Save(g, resultsWriter);
                    try
                    {
                        resultsWriter.Flush();
                    }
                    catch (ObjectDisposedException)
                    {
                        // resultWriter is already closed
                    }
                    return(BrightstarSparqlResultsType.Graph);
                }
                throw new BrightstarInternalException(
                          String.Format("Unexpected return type from QueryProcessor.ProcessQuery: {0}",
                                        queryResult.GetType()));
            }
            catch (Exception ex)
            {
                Logging.LogError(BrightstarEventId.SparqlExecutionError,
                                 "Error Executing query {0}. Cause: {1}",
                                 query.ToString(), ex);
                throw;
            }
        }
Example #11
0
        // See https://github.com/dotnetrdf/dotnetrdf/blob/5b7fc480346c90eb9b164fb4f8ee09f378442d52/Libraries/dotNetRDF.Web/HandlerHelper.cs#L157
        /// <summary>
        /// Helper function which returns the Results (Graph/Triple Store/SPARQL Results) back to the Client in one of their accepted formats
        /// </summary>
        /// <param name="context">Context of the HTTP Request</param>
        /// <param name="result">Results of the Sparql Query</param>
        /// <param name="config">Handler Configuration</param>
        public static void SendToClient(HttpContext context, SparqlQueryResult result)
        {
            MimeTypeDefinition definition = null;
            const string       TEXT_PLAIN = "text/plain";
            var acceptTypes = context.Request.Headers[HeaderNames.Accept];

            // Return the Results
            if (result.SparqlResultSet != null)
            {
                ISparqlResultsWriter sparqlWriter = null;

                // Try and get a MIME Type Definition using the HTTP Requests Accept Header
                if (acceptTypes.Count > 0)
                {
                    definition = MimeTypesHelper.GetDefinitions((IEnumerable <string>)acceptTypes).FirstOrDefault(d => d.CanWriteSparqlResults);
                }
                // Try and get the registered Definition for SPARQL Results XML
                if (definition == null)
                {
                    definition = MimeTypesHelper.GetDefinitions(MimeTypesHelper.SparqlResultsXml[0]).FirstOrDefault();
                }
                // If Definition is still null create a temporary definition
                if (definition == null)
                {
                    definition = new MimeTypeDefinition("SPARQL Results XML", MimeTypesHelper.SparqlResultsXml, Enumerable.Empty <String>());
                    definition.SparqlResultsWriterType = typeof(VDS.RDF.Writing.SparqlXmlWriter);
                }

                // Set up the Writer appropriately
                sparqlWriter = definition.GetSparqlResultsWriter();
                context.Response.ContentType = definition.CanonicalMimeType;
                // HandlerHelper.ApplyWriterOptions(sparqlWriter, config);

                // Send Result Set to Client
                context.Response.Headers[HeaderNames.ContentEncoding] = definition.Encoding.WebName;
                sparqlWriter.Save(result.SparqlResultSet, new StreamWriter(context.Response.Body, definition.Encoding));
            }
            else if (result.Graph != null)
            {
                IRdfWriter rdfWriter = null;
                var        ctype     = TEXT_PLAIN;
                // Try and get a MIME Type Definition using the HTTP Requests Accept Header
                if (acceptTypes.Count > 0)
                {
                    definition = MimeTypesHelper.GetDefinitions((IEnumerable <string>)acceptTypes).FirstOrDefault(d => d.CanWriteRdf);
                }
                if (definition == null)
                {
                    // If no appropriate definition then use the GetWriter method instead
                    rdfWriter = MimeTypesHelper.GetWriter((IEnumerable <string>)acceptTypes, out ctype);
                }
                else
                {
                    rdfWriter = definition.GetRdfWriter();
                }

                // Setup the writer
                if (definition != null)
                {
                    ctype = definition.CanonicalMimeType;
                }
                context.Response.ContentType = ctype;
                //HandlerHelper.ApplyWriterOptions(rdfWriter, config);

                // Clear any existing Response
                //context.Response.Clear();

                // Send Graph to Client
                if (definition != null)
                {
                    context.Response.Headers[HeaderNames.ContentEncoding] = definition.Encoding.WebName;
                    rdfWriter.Save(result.Graph, new StreamWriter(context.Response.Body, definition.Encoding));
                }
                else
                {
                    rdfWriter.Save(result.Graph, new StreamWriter(context.Response.Body));
                }
            }
            else
            {
                Debug.Assert(result == SparqlQueryResult.Null);
            }
        }
Example #12
0
        static void DoQuery(Dictionary <String, String> arguments)
        {
            SparqlRemoteEndpoint endpoint;
            bool verbose = arguments.ContainsKey("verbose") || arguments.ContainsKey("v");

            if (verbose)
            {
                Options.HttpDebugging = true;
            }

            //First get the Server to which we are going to connect
            try
            {
                if (arguments.ContainsKey("server") && !arguments["server"].Equals(String.Empty))
                {
                    endpoint = new SparqlRemoteEndpoint(new Uri(arguments["server"]));
                }
                else if (arguments.ContainsKey("service") && !arguments["service"].Equals(String.Empty))
                {
                    endpoint = new SparqlRemoteEndpoint(new Uri(arguments["service"]));
                }
                else
                {
                    Console.Error.WriteLine("soh: Error: Required --server/--service argument not present");
                    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: SPARQL Endpoint for URI " + endpoint.Uri + " created OK");
            }

            //Then decide where to get the query to execute from
            SparqlQueryParser parser = new SparqlQueryParser();
            SparqlQuery       query;

            try
            {
                if (arguments.ContainsKey("query") && !arguments["query"].Equals(String.Empty))
                {
                    query = parser.ParseFromFile(arguments["query"]);
                }
                else if (arguments.ContainsKey("file") && !arguments["file"].Equals(String.Empty))
                {
                    query = parser.ParseFromFile(arguments["file"]);
                }
                else if (arguments.ContainsKey("$1") && !arguments["$1"].Equals(String.Empty))
                {
                    query = parser.ParseFromString(arguments["$1"]);
                }
                else
                {
                    Console.Error.WriteLine("soh: Error: Required SPARQL Query not found - may be specified as --file/--query FILE or as final argument");
                    Environment.Exit(-1);
                    return;
                }
            }
            catch (Exception ex)
            {
                Console.Error.WriteLine("soh: Error: Error Parsing SPARQL Query");
                Console.Error.WriteLine(ex.Message);
                Environment.Exit(-1);
                return;
            }

            if (verbose)
            {
                Console.Error.WriteLine("soh: Parsed Query OK");
                Console.Error.WriteLine("soh: dotNetRDF's interpretation of the Query:");
                SparqlFormatter formatter = new SparqlFormatter();
                Console.Error.WriteLine(formatter.Format(query));
                Console.Error.WriteLine("soh: Submitting Query");
            }

            try
            {
                using (HttpWebResponse response = endpoint.QueryRaw(query.ToString()))
                {
                    MimeTypeDefinition definition = MimeTypesHelper.GetDefinitions(response.ContentType).FirstOrDefault();
                    Encoding           enc;
                    if (definition != null)
                    {
                        enc = definition.Encoding;
                    }
                    else if (!response.ContentEncoding.Equals(String.Empty))
                    {
                        enc = Encoding.GetEncoding(response.ContentEncoding);
                    }
                    else if (response.ContentType.Contains("charset="))
                    {
                        enc = Encoding.GetEncoding(response.ContentType.Substring(response.ContentType.IndexOf('=') + 1));
                    }
                    else
                    {
                        enc = Console.OutputEncoding;
                    }

                    if (verbose)
                    {
                        Console.Error.WriteLine("soh: Got Response from SPARQL Endpoint OK");
                        Console.Error.WriteLine("soh: Content-Type: " + response.ContentType);
                        Console.Error.WriteLine("soh: Content-Encoding: " + enc.WebName);
                    }

                    String requestedType = arguments.ContainsKey("accept") ? arguments["accept"] : null;

                    if (requestedType == null || response.ContentType.StartsWith(requestedType, StringComparison.OrdinalIgnoreCase))
                    {
                        //If no --accept (OR matches servers content type) then just return whatever the server has given us
                        using (StreamReader reader = new StreamReader(response.GetResponseStream()))
                        {
                            using (StreamWriter writer = new StreamWriter(Console.OpenStandardOutput(), enc))
                            {
                                while (!reader.EndOfStream)
                                {
                                    writer.WriteLine(reader.ReadLine());
                                }
                                writer.Close();
                            }
                            reader.Close();
                        }
                    }
                    else
                    {
                        if (verbose)
                        {
                            Console.Error.WriteLine("soh: Warning: Retrieved Content Type '" + response.ContentType + "' does not match your desired Content Type '" + requestedType + "' so dotNetRDF will not attempt to transcode the response into your desired format");
                        }

                        //Requested Type Doesn't match servers returned type so parse then serialize
                        MimeTypeDefinition outputDefinition;
                        try
                        {
                            ISparqlResultsReader sparqlParser = MimeTypesHelper.GetSparqlParser(response.ContentType);
                            SparqlResultSet      results      = new SparqlResultSet();
                            using (StreamReader reader = new StreamReader(response.GetResponseStream()))
                            {
                                sparqlParser.Load(results, reader);
                                reader.Close();
                            }

                            outputDefinition = MimeTypesHelper.GetDefinitions(requestedType).FirstOrDefault(d => d.CanWriteSparqlResults || d.CanWriteRdf);
                            if (outputDefinition == null)
                            {
                                throw new RdfWriterSelectionException("No MIME Type Definition for the MIME Type '" + requestedType + "' was found that can write SPARQL Results/RDF");
                            }
                            ISparqlResultsWriter writer = outputDefinition.GetSparqlResultsWriter();
                            Console.OutputEncoding = outputDefinition.Encoding;
                            writer.Save(results, new StreamWriter(Console.OpenStandardOutput(), outputDefinition.Encoding));
                        }
                        catch (RdfParserSelectionException)
                        {
                            try
                            {
                                IRdfReader rdfParser = MimeTypesHelper.GetParser(response.ContentType);
                                Graph      g         = new Graph();
                                using (StreamReader reader = new StreamReader(response.GetResponseStream()))
                                {
                                    rdfParser.Load(g, reader);
                                    reader.Close();
                                }

                                outputDefinition = MimeTypesHelper.GetDefinitions(requestedType).FirstOrDefault(d => d.CanWriteRdf);
                                if (outputDefinition == null)
                                {
                                    throw new RdfWriterSelectionException("No MIME Type Definition for the MIME Type '" + requestedType + "' was found that can write RDF");
                                }
                                IRdfWriter writer = outputDefinition.GetRdfWriter();
                                Console.OutputEncoding = outputDefinition.Encoding;
                                writer.Save(g, new StreamWriter(Console.OpenStandardOutput(), outputDefinition.Encoding));
                            }
                            catch (Exception ex)
                            {
                                //For any other exception show a warning
                                Console.Error.WriteLine("soh: Warning: You wanted results in the format '" + requestedType + "' but the server returned '" + response.ContentType + "' and dotNetRDF was unable to translate the response into your desired format.");
                                Console.Error.WriteLine(ex.Message);
                            }
                        }
                        catch (Exception ex)
                        {
                            //For any other exception show a warning
                            Console.Error.WriteLine("soh: Warning: You wanted results in the format '" + requestedType + "' but the server returned '" + response.ContentType + "' and dotNetRDF was unable to translate the response into your desired format.");
                            Console.Error.WriteLine(ex.Message);
                        }
                    }


                    response.Close();
                }

                if (verbose)
                {
                    Console.Error.WriteLine("soh: Query Completed OK");
                }
            }
            catch (Exception ex)
            {
                Console.Error.WriteLine("soh: Error: Error while making the SPARQL Query");
                Console.Error.WriteLine(ex.Message);
                Environment.Exit(-1);
                return;
            }
        }