/// <summary>
/// Given the Accept and the Accept-Charset headers of the request message computes the media type, encoding and <see cref="ODataFormat"/>
/// to be used for the response message.
/// </summary>
/// <param name="settings">The writer settings to use for serializing the response payload.</param>
/// <param name="payloadKind">The kind of payload to be serialized as part of the response message.</param>
/// <param name="mediaType">The media type to be used in the response message.</param>
/// <param name="encoding">The encoding to be used in the response message.</param>
/// <returns>The <see cref="ODataFormat"/> used when serializing the response.</returns>
internal static ODataFormat GetContentTypeFromSettings(
ODataWriterSettings settings,
ODataPayloadKind payloadKind,
out MediaType mediaType,
out Encoding encoding)
{
DebugUtils.CheckNoExternalCallers();
Debug.Assert(settings != null, "settings != null");
// compute format, media type and encoding
ODataFormat format;
if (settings.AcceptableMediaTypes != null)
{
mediaType = GetMediaType(settings.AcceptableMediaTypes, payloadKind, out format);
encoding = GetEncoding(settings.AcceptableCharsets, payloadKind, mediaType);
}
else
{
mediaType = GetDefaultMediaType(payloadKind, settings.Format, out format);
encoding = mediaType.SelectEncoding();
}
return(format);
}
/// <summary>Gets the best encoding available for the specified charset request.</summary>
/// <param name="acceptableCharsets">
/// The Accept-Charset header value (eg: "iso-8859-5, unicode-1-1;q=0.8").
/// </param>
/// <param name="mediaType">The media type used to compute the default encoding for the payload.</param>
/// <param name="utf8Encoding">The encoding to use for UTF-8 charsets; we use the one without the BOM.</param>
/// <param name="defaultEncoding">The encoding to use if no encoding could be computed from the <paramref name="acceptableCharsets"/> or <paramref name="mediaType"/>.</param>
/// <returns>An Encoding object appropriate to the specifed charset request.</returns>
internal static Encoding EncodingFromAcceptableCharsets(string acceptableCharsets, MediaType mediaType, Encoding utf8Encoding, Encoding defaultEncoding)
{
DebugUtils.CheckNoExternalCallers();
Debug.Assert(mediaType != null, "mediaType != null");
// Determines the appropriate encoding mapping according to
// RFC 2616.14.2 (http://tools.ietf.org/html/rfc2616#section-14.2).
Encoding result = null;
if (!string.IsNullOrEmpty(acceptableCharsets))
{
// PERF: in the future if we find that computing the encoding from the accept charsets is
// too expensive we could introduce a cache of original strings to resolved encoding.
List <CharsetPart> parts = new List <CharsetPart>(AcceptCharsetParts(acceptableCharsets));
parts.Sort(delegate(CharsetPart x, CharsetPart y)
{
return(y.Quality - x.Quality);
});
foreach (CharsetPart part in parts)
{
if (part.Quality > 0)
{
// When UTF-8 is specified, select the version that doesn't use the BOM.
if (String.Compare("utf-8", part.Charset, StringComparison.OrdinalIgnoreCase) == 0)
{
result = utf8Encoding;
break;
}
else
{
result = GetEncodingFromCharsetName(part.Charset);
if (result != null)
{
break;
}
// If the charset is not supported it is ignored so other possible charsets are evaluated.
}
}
}
}
// No Charset was specifed, or if charsets were specified, no valid charset was found.
// Returning a different charset is also valid. Get the default encoding for the media type.
if (result == null)
{
result = mediaType.SelectEncoding();
if (result == null)
{
return(defaultEncoding);
}
}
return(result);
}
/// <summary>Reads a Content-Type header and extracts the media type's name (type/subtype) and encoding.</summary>
/// <param name="contentType">The Content-Type header.</param>
/// <param name="mediaTypeName">The media type in standard type/subtype form, without parameters.</param>
/// <param name="encoding">Encoding (possibly null).</param>
/// <returns>parameters of content type</returns>
internal static IList <KeyValuePair <string, string> > ReadContentType(string contentType, out string mediaTypeName, out Encoding encoding)
{
DebugUtils.CheckNoExternalCallers();
if (String.IsNullOrEmpty(contentType))
{
throw new ODataException(Strings.HttpUtils_ContentTypeMissing);
}
MediaType mediaType = ReadMediaTypes(contentType)[0];
mediaTypeName = mediaType.TypeName;
encoding = mediaType.SelectEncoding();
return(mediaType.Parameters);
}
/// <summary>Gets the best encoding available for the specified charset request.</summary>
/// <param name="acceptableCharsets">
/// The Accept-Charset header value (eg: "iso-8859-5, unicode-1-1;q=0.8").
/// </param>
/// <param name="mediaType">The media type used to compute the default encoding for the payload.</param>
/// <param name="utf8Encoding">The encoding to use for UTF-8 charsets; we use the one without the BOM.</param>
/// <param name="defaultEncoding">The encoding to use if no encoding could be computed from the <paramref name="acceptableCharsets"/> or <paramref name="mediaType"/>.</param>
/// <returns>An Encoding object appropriate to the specifed charset request.</returns>
internal static Encoding EncodingFromAcceptableCharsets(string acceptableCharsets, MediaType mediaType, Encoding utf8Encoding, Encoding defaultEncoding)
{
DebugUtils.CheckNoExternalCallers();
Debug.Assert(mediaType != null, "mediaType != null");
// Determines the appropriate encoding mapping according to
// RFC 2616.14.2 (http://tools.ietf.org/html/rfc2616#section-14.2).
Encoding result = null;
if (!string.IsNullOrEmpty(acceptableCharsets))
{
// PERF: in the future if we find that computing the encoding from the accept charsets is
// too expensive we could introduce a cache of original strings to resolved encoding.
List<CharsetPart> parts = new List<CharsetPart>(AcceptCharsetParts(acceptableCharsets));
parts.Sort(delegate(CharsetPart x, CharsetPart y)
{
return y.Quality - x.Quality;
});
foreach (CharsetPart part in parts)
{
if (part.Quality > 0)
{
// When UTF-8 is specified, select the version that doesn't use the BOM.
if (String.Compare("utf-8", part.Charset, StringComparison.OrdinalIgnoreCase) == 0)
{
result = utf8Encoding;
break;
}
else
{
result = GetEncodingFromCharsetName(part.Charset);
if (result != null)
{
break;
}
// If the charset is not supported it is ignored so other possible charsets are evaluated.
}
}
}
}
// No Charset was specifed, or if charsets were specified, no valid charset was found.
// Returning a different charset is also valid. Get the default encoding for the media type.
if (result == null)
{
result = mediaType.SelectEncoding();
if (result == null)
{
return defaultEncoding;
}
}
return result;
}
/// <summary>
/// Given the Accept and the Accept-Charset headers of the request message computes the media type, encoding and <see cref="ODataFormat"/>
/// to be used for the response message.
/// </summary>
/// <param name="settings">The writer settings to use for serializing the response payload.</param>
/// <param name="payloadKind">The kind of payload to be serialized as part of the response message.</param>
/// <param name="mediaType">The media type to be used in the response message.</param>
/// <param name="encoding">The encoding to be used in the response message.</param>
/// <returns>The <see cref="ODataFormat"/> used when serializing the response.</returns>
internal static ODataFormat GetContentTypeFromSettings(
ODataWriterSettings settings,
ODataPayloadKind payloadKind,
out MediaType mediaType,
out Encoding encoding)
{
DebugUtils.CheckNoExternalCallers();
Debug.Assert(settings != null, "settings != null");
// compute format, media type and encoding
ODataFormat format;
if (settings.AcceptableMediaTypes != null)
{
mediaType = GetMediaType(settings.AcceptableMediaTypes, payloadKind, out format);
encoding = GetEncoding(settings.AcceptableCharsets, payloadKind, mediaType);
}
else
{
mediaType = GetDefaultMediaType(payloadKind, settings.Format, out format);
encoding = mediaType.SelectEncoding();
}
return format;
}
