/// <summary>
/// Attempts to load a RDF dataset asynchronously from the given URI using a RDF Handler.
/// </summary>
/// <param name="handler">RDF Handler to use.</param>
/// <param name="u">URI to attempt to get a RDF dataset from.</param>
/// <param name="callback">Callback to invoke when the operation completes.</param>
/// <param name="state">State to pass to the callback.</param>
/// <remarks>
/// <para>
/// Attempts to select the relevant Store Parser based on the Content Type header returned in the HTTP Response.
/// </para>
/// <para>
/// If the loading completes normally the callback will be invoked normally, if an error occurs it will be invoked and passed an instance of <see cref="AsyncError"/> as the state which contains details of the error and the original state.
/// </para>
/// </remarks>
public static void LoadDataset(IRdfHandler handler, Uri u, RdfHandlerCallback callback, Object state)
{
Load(handler, u, (IStoreReader)null, callback, state);
}
/// <summary>
/// Attempts to load a RDF dataset asynchronously from the given URI using a RDF Handler.
/// </summary>
/// <param name="handler">RDF Handler to use.</param>
/// <param name="u">URI to attempt to get a RDF dataset from.</param>
/// <param name="parser">Parser to use to parse the RDF dataset.</param>
/// <param name="callback">Callback to invoke when the operation completes.</param>
/// <param name="state">State to pass to the callback.</param>
/// <remarks>
/// <para>
/// If the <paramref name="parser"/> parameter is set to null then this method attempts to select the relevant Store Parser based on the Content Type header returned in the HTTP Response.
/// </para>
/// <para>
/// If you know ahead of time the Content Type you can explicitly pass in the parser to use.
/// </para>
/// <para>
/// If the loading completes normally the callback will be invoked normally, if an error occurs it will be invoked and passed an instance of <see cref="AsyncError"/> as the state which contains details of the error and the original state.
/// </para>
/// </remarks>
public static void Load(IRdfHandler handler, Uri u, IStoreReader parser, RdfHandlerCallback callback, Object state)
{
if (u == null)
{
throw new RdfParseException("Cannot read a RDF dataset from a null URI");
}
if (handler == null)
{
throw new RdfParseException("Cannot read a RDF dataset using a null RDF handler");
}
try
{
if (u.IsFile)
{
// Invoke FileLoader instead
RaiseWarning("This is a file: URI so invoking the FileLoader instead");
if (Path.DirectorySeparatorChar == '/')
{
FileLoader.Load(handler, u.AbsoluteUri.Substring(7), parser);
}
else
{
FileLoader.Load(handler, u.AbsoluteUri.Substring(8), parser);
}
// FileLoader.Load() will run synchronously so once this completes we can invoke the callback
callback(handler, state);
return;
}
if (u.Scheme.Equals("data"))
{
// Invoke DataUriLoader instead
RaiseWarning("This is a data: URI so invoking the DataUriLoader instead");
DataUriLoader.Load(handler, u);
// After DataUriLoader.Load() has run (which happens synchronously) can invoke the callback
callback(handler, state);
return;
}
// Sanitise the URI to remove any Fragment ID
u = Tools.StripUriFragment(u);
// Setup the Request
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(u);
// Want to ask for RDF dataset formats
if (parser != null)
{
// If a non-null parser set up a HTTP Header that is just for the given parser
request.Accept = MimeTypesHelper.CustomHttpAcceptHeader(parser);
}
else
{
request.Accept = MimeTypesHelper.HttpAcceptHeader;
}
// Use HTTP GET
request.Method = "GET";
#if !NETCORE
request.Timeout = Options.UriLoaderTimeout;
#endif
if (_userAgent != null && !_userAgent.Equals(String.Empty))
{
#if NETCORE
request.Headers[HttpRequestHeader.UserAgent] = _userAgent;
#else
request.UserAgent = _userAgent;
#endif
}
Tools.HttpDebugRequest(request);
try
{
request.BeginGetResponse(result =>
{
try
{
using (HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(result))
{
Tools.HttpDebugResponse(response);
// Get a Parser and load the RDF
if (parser == null)
{
try
{
// Only need to auto-detect the parser if a specific one wasn't specified
parser = MimeTypesHelper.GetStoreParser(response.ContentType);
parser.Warning += RaiseWarning;
parser.Load(handler, new StreamReader(response.GetResponseStream()));
}
catch (RdfParserSelectionException)
{
RaiseStoreWarning("Unable to select a RDF Dataset parser based on Content-Type: " + response.ContentType + " - seeing if the content is an RDF Graph instead");
try
{
// If not a RDF Dataset format see if it is a Graph
IRdfReader rdfParser = MimeTypesHelper.GetParser(response.ContentType);
rdfParser.Load(handler, new StreamReader(response.GetResponseStream()));
}
catch (RdfParserSelectionException)
{
String data = new StreamReader(response.GetResponseStream()).ReadToEnd();
parser = StringParser.GetDatasetParser(data);
parser.Warning += RaiseStoreWarning;
parser.Load(handler, new StringReader(data));
}
}
}
else
{
parser.Warning += RaiseStoreWarning;
parser.Load(handler, new StreamReader(response.GetResponseStream()));
}
// Finally can invoke the callback
callback(handler, state);
}
}
catch (WebException webEx)
{
if (webEx.Response != null)
{
Tools.HttpDebugResponse((HttpWebResponse)webEx.Response);
}
callback(handler, new AsyncError(new RdfParseException("A HTTP Error occurred loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exeption for details", webEx), state));
}
catch (Exception ex)
{
callback(handler, new AsyncError(new RdfParseException("Unexpected error while loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exception for details", ex), state));
}
}, null);
}
catch (WebException webEx)
{
if (webEx.Response != null)
{
Tools.HttpDebugResponse((HttpWebResponse)webEx.Response);
}
callback(handler, new AsyncError(new RdfParseException("A HTTP Error occurred loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exeption for details", webEx), state));
}
catch (Exception ex)
{
callback(handler, new AsyncError(new RdfParseException("Unexpected error while loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exception for details", ex), state));
}
}
catch (UriFormatException uriEx)
{
// Uri Format Invalid
throw new RdfException("Unable to load from the given URI '" + u.AbsoluteUri + "' since it's format was invalid, see inner exception for details", uriEx);
}
}
/// <summary>
/// Attempts to load a RDF Graph from a URI asynchronously using an RDF Handler
/// </summary>
/// <param name="handler">RDF Handler to use</param>
/// <param name="u">URI to load from</param>
/// <param name="callback">Callback to invoke when the operation completes</param>
/// <param name="state">State to pass to the callback</param>
/// <remarks>
/// <para>
/// Attempts to autodetect the RDF format based on the Content-Type header of the HTTP response
/// </para>
/// <para>
/// If the loading completes normally the callback will be invoked normally, if an error occurs it will be invoked and passed an instance of <see cref="AsyncError"/> as the state which contains details of the error and the original state.
/// </para>
/// </remarks>
public static void Load(IRdfHandler handler, Uri u, RdfHandlerCallback callback, Object state)
{
UriLoader.Load(handler, u, (IRdfReader)null, callback, state);
}
/// <summary>
/// Attempts to load a RDF Graph from a URI asynchronously using an RDF Handler
/// </summary>
/// <param name="handler">RDF Handler to use</param>
/// <param name="u">URI to load from</param>
/// <param name="parser">Parser to use</param>
/// <param name="callback">Callback to invoke when the operation completes</param>
/// <param name="state">State to pass to the callback</param>
/// <remarks>
/// <para>
/// Uses the supplied parser to attempt parsing regardless of the actual Content Type returned
/// </para>
/// <para>
/// In the event that the URI is a File URI the <see cref="FileLoader">FileLoader</see> will be used instead
/// </para>
/// <para>
/// If the URI is a Data URI then the <see cref="DataUriLoader">DataUriLoader</see> will be used instead.
/// </para>
/// <para>
/// If the loading completes normally the callback will be invoked normally, if an error occurs it will be invoked and passed an instance of <see cref="AsyncError"/> as the state which contains details of the error and the original state.
/// </para>
/// </remarks>
public static void Load(IRdfHandler handler, Uri u, IRdfReader parser, RdfHandlerCallback callback, Object state)
{
if (handler == null)
{
throw new RdfParseException("Cannot read RDF using a null RDF Handler");
}
if (u == null)
{
throw new RdfParseException("Cannot load RDF from a null URI");
}
try
{
#if SILVERLIGHT
if (u.IsFile())
#else
if (u.IsFile)
#endif
{
#if PORTABLE
throw new PlatformNotSupportedException("FileLoader is not supported by the Portable Class Library build");
#else
//Invoke FileLoader instead
RaiseWarning("This is a file: URI so invoking the FileLoader instead");
if (Path.DirectorySeparatorChar == '/')
{
FileLoader.Load(handler, u.AbsoluteUri.Substring(7), parser);
}
else
{
FileLoader.Load(handler, u.AbsoluteUri.Substring(8), parser);
}
//FileLoader.Load() will run synchronously so once this completes we can invoke the callback
callback(handler, state);
return;
#endif
}
if (u.Scheme.Equals("data"))
{
//Invoke DataUriLoader instead
RaiseWarning("This is a data: URI so invoking the DataUriLoader instead");
DataUriLoader.Load(handler, u);
//After DataUriLoader.Load() has run (which happens synchronously) can invoke the callback
callback(handler, state);
return;
}
//Sanitise the URI to remove any Fragment ID
u = Tools.StripUriFragment(u);
//TODO: Add use of Cache into here, this is tricky because this code is primarily intended for Silverlight where we disable the cache purposefully
//Setup the Request
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(u);
//Want to ask for RDF formats
if (parser != null)
{
//If a non-null parser set up a HTTP Header that is just for the given parser
request.Accept = MimeTypesHelper.CustomHttpAcceptHeader(parser);
}
else
{
request.Accept = MimeTypesHelper.HttpAcceptHeader;
}
//Use HTTP GET
request.Method = "GET";
#if !SILVERLIGHT
request.Timeout = Options.UriLoaderTimeout;
#endif
if (_userAgent != null && !_userAgent.Equals(String.Empty))
{
#if PORTABLE
request.Headers[HttpRequestHeader.UserAgent] = _userAgent;
#else
request.UserAgent = _userAgent;
#endif
}
Tools.HttpDebugRequest(request);
try
{
request.BeginGetResponse(result =>
{
try
{
using (HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(result))
{
Tools.HttpDebugResponse(response);
//Get a Parser and load the RDF
if (parser == null)
{
//Only need to auto-detect the parser if a specific one wasn't specified
parser = MimeTypesHelper.GetParser(response.ContentType);
}
parser.Warning += RaiseWarning;
parser.Load(handler, new StreamReader(response.GetResponseStream()));
//Finally can invoke the callback
callback(handler, state);
}
}
catch (WebException webEx)
{
if (webEx.Response != null)
{
Tools.HttpDebugResponse((HttpWebResponse)webEx.Response);
}
callback(handler, new AsyncError(new RdfParseException("A HTTP Error occurred loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exeption for details", webEx), state));
}
catch (Exception ex)
{
callback(handler, new AsyncError(new RdfParseException("Unexpected error while loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exception for details", ex), state));
}
}, null);
}
catch (WebException webEx)
{
if (webEx.Response != null)
{
Tools.HttpDebugResponse((HttpWebResponse)webEx.Response);
}
callback(handler, new AsyncError(new RdfParseException("A HTTP Error occurred loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exeption for details", webEx), state));
}
catch (Exception ex)
{
callback(handler, new AsyncError(new RdfParseException("Unexpected error while loading the URI '" + u.AbsoluteUri + "' asynchronously, see inner exception for details", ex), state));
}
}
#if PORTABLE
catch (FormatException uriEx)
#else
catch (UriFormatException uriEx)
#endif
{
//URI Format Invalid
throw new RdfParseException("Unable to load from the given URI '" + u.AbsoluteUri + "' since it's format was invalid, see inner exception for details", uriEx);
}
}
/// <summary>
/// Attempts to load a RDF dataset asynchronously from the given URI using a RDF Handler
/// </summary>
/// <param name="handler">RDF Handler to use</param>
/// <param name="u">URI to attempt to get a RDF dataset from</param>
/// <param name="callback">Callback to invoke when the operation completes</param>
/// <param name="state">State to pass to the callback</param>
/// <remarks>
/// <para>
/// Attempts to select the relevant Store Parser based on the Content Type header returned in the HTTP Response.
/// </para>
/// </remarks>
public static void LoadDataset(IRdfHandler handler, Uri u, RdfHandlerCallback callback, Object state)
{
UriLoader.Load(handler, u, (IStoreReader)null, callback, state);
}
/// <summary>
/// Attempts to load a RDF dataset asynchronously from the given URI using a RDF Handler
/// </summary>
/// <param name="handler">RDF Handler to use</param>
/// <param name="u">URI to attempt to get a RDF dataset from</param>
/// <param name="parser">Parser to use to parse the RDF dataset</param>
/// <param name="callback">Callback to invoke when the operation completes</param>
/// <param name="state">State to pass to the callback</param>
/// <remarks>
/// <para>
/// If the <paramref name="parser"/> parameter is set to null then this method attempts to select the relevant Store Parser based on the Content Type header returned in the HTTP Response.
/// </para>
/// <para>
/// If you know ahead of time the Content Type you can explicitly pass in the parser to use.
/// </para>
/// </remarks>
public static void Load(IRdfHandler handler, Uri u, IStoreReader parser, RdfHandlerCallback callback, Object state)
{
if (u == null) throw new RdfParseException("Cannot read a RDF dataset from a null URI");
if (handler == null) throw new RdfParseException("Cannot read a RDF dataset using a null RDF handler");
try
{
#if SILVERLIGHT
if (u.IsFile())
#else
if (u.IsFile)
#endif
{
//Invoke FileLoader instead
RaiseWarning("This is a file: URI so invoking the FileLoader instead");
if (Path.DirectorySeparatorChar == '/')
{
FileLoader.Load(handler, u.ToString().Substring(7), parser);
}
else
{
FileLoader.Load(handler, u.ToString().Substring(8), parser);
}
//FileLoader.Load() will run synchronously so once this completes we can invoke the callback
callback(handler, state);
return;
}
if (u.Scheme.Equals("data"))
{
//Invoke DataUriLoader instead
RaiseWarning("This is a data: URI so invoking the DataUriLoader instead");
DataUriLoader.Load(handler, u);
//After DataUriLoader.Load() has run (which happens synchronously) can invoke the callback
callback(handler, state);
return;
}
//Sanitise the URI to remove any Fragment ID
u = Tools.StripUriFragment(u);
//Setup the Request
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(u);
//Want to ask for RDF dataset formats
if (parser != null)
{
//If a non-null parser set up a HTTP Header that is just for the given parser
request.Accept = MimeTypesHelper.CustomHttpAcceptHeader(parser);
}
else
{
request.Accept = MimeTypesHelper.HttpAcceptHeader;
}
//Use HTTP GET
request.Method = "GET";
#if !SILVERLIGHT
request.Timeout = Options.UriLoaderTimeout;
#endif
if (_userAgent != null && !_userAgent.Equals(String.Empty))
{
request.UserAgent = _userAgent;
}
#if DEBUG
//HTTP Debugging
if (Options.HttpDebugging)
{
Tools.HttpDebugRequest(request);
}
#endif
request.BeginGetResponse(result =>
{
using (HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(result))
{
#if DEBUG
if (Options.HttpDebugging)
{
Tools.HttpDebugResponse(response);
}
#endif
//Get a Parser and load the RDF
if (parser == null)
{
try
{
//Only need to auto-detect the parser if a specific one wasn't specified
parser = MimeTypesHelper.GetStoreParser(response.ContentType);
parser.Warning += RaiseWarning;
parser.Load(handler, new StreamParams(response.GetResponseStream()));
}
catch (RdfParserSelectionException)
{
RaiseStoreWarning("Unable to select a RDF Dataset parser based on Content-Type: " + response.ContentType + " - seeing if the content is an RDF Graph instead");
try
{
//If not a RDF Dataset format see if it is a Graph
IRdfReader rdfParser = MimeTypesHelper.GetParser(response.ContentType);
rdfParser.Load(handler, new StreamReader(response.GetResponseStream()));
}
catch (RdfParserSelectionException)
{
String data = new StreamReader(response.GetResponseStream()).ReadToEnd();
parser = StringParser.GetDatasetParser(data);
parser.Warning += RaiseStoreWarning;
parser.Load(handler, new TextReaderParams(new StringReader(data)));
}
}
}
else
{
parser.Warning += RaiseStoreWarning;
parser.Load(handler, new StreamParams(response.GetResponseStream()));
}
//Finally can invoke the callback
callback(handler, state);
}
}, null);
}
catch (UriFormatException uriEx)
{
//Uri Format Invalid
throw new RdfException("Unable to load from the given URI '" + u.ToString() + "' since it's format was invalid, see inner exception for details", uriEx);
}
catch (WebException webEx)
{
#if DEBUG
if (Options.HttpDebugging)
{
if (webEx.Response != null) Tools.HttpDebugResponse((HttpWebResponse)webEx.Response);
}
#endif
//Some sort of HTTP Error occurred
throw new WebException("A HTTP Error occurred resolving the URI '" + u.ToString() + "', see innner exception for details", webEx);
}
}
