/// <summary>
/// Determines the best <see cref="Encoding"/> amongst the supported encodings
/// for reading or writing an HTTP entity body based on the provided <paramref name="contentHeaders"/>.
/// </summary>
/// <param name="contentHeaders">The content headers provided as part of the request or response.</param>
/// <returns>The <see cref="Encoding"/> to use when reading the request or writing the response.</returns>
protected Encoding SelectCharacterEncoding(HttpContentHeaders contentHeaders)
{
Encoding encoding = null;
if (contentHeaders != null && contentHeaders.ContentType != null)
{
// Find encoding based on content type charset parameter
string charset = contentHeaders.ContentType.CharSet;
if (!String.IsNullOrWhiteSpace(charset))
{
encoding =
SupportedEncodings.FirstOrDefault(
enc => charset.Equals(enc.WebName, StringComparison.OrdinalIgnoreCase));
}
}
if (encoding == null)
{
// We didn't find a character encoding match based on the content headers.
// Instead we try getting the default character encoding.
encoding = SupportedEncodings.FirstOrDefault();
}
if (encoding == null)
{
// No supported encoding was found so there is no way for us to start reading or writing.
throw new InvalidOperationException(RS.Format(Properties.Resources.MediaTypeFormatterNoEncoding, GetType().Name));
}
return(encoding);
}
private Encoding MatchAcceptCharacterEncoding(IList <StringWithQualityHeaderValue> acceptCharsetHeaders)
{
if (acceptCharsetHeaders != null && acceptCharsetHeaders.Count > 0)
{
var sortedAcceptCharsetHeaders = acceptCharsetHeaders
.Where(acceptCharset =>
acceptCharset.Quality != HeaderQuality.NoMatch)
.OrderByDescending(
m => m, StringWithQualityHeaderValueComparer.QualityComparer);
foreach (var acceptCharset in sortedAcceptCharsetHeaders)
{
var charset = acceptCharset.Value;
if (!string.IsNullOrWhiteSpace(charset))
{
var encoding = SupportedEncodings.FirstOrDefault(
supportedEncoding =>
charset.Equals(supportedEncoding.WebName,
StringComparison.OrdinalIgnoreCase) ||
charset.Equals("*", StringComparison.Ordinal));
if (encoding != null)
{
return(encoding);
}
}
}
}
return(null);
}
public override async Task <object> ReadFromStreamAsync(Type type, Stream readStream, HttpContent content, IFormatterLogger formatterLogger)
{
var instance = await Task.Run(() =>
{
var serializer = JsonSerializer.Create(SerializerSettings);
using (var streamReader = new StreamReader(readStream, SupportedEncodings.FirstOrDefault() ?? new UTF8Encoding()))
using (var jsonTextReader = new JsonTextReader(streamReader))
return(serializer.Deserialize(jsonTextReader));
});
return(instance);
}
/// <summary>
/// Determines the best <see cref="Encoding"/> amongst the supported encodings
/// for reading or writing an HTTP entity body based on the provided <paramref name="contentTypeHeader"/>.
/// </summary>
/// <param name="context">The formatter context associated with the call.
/// </param>
/// <returns>The <see cref="Encoding"/> to use when reading the request or writing the response.</returns>
public virtual Encoding SelectCharacterEncoding(OutputFormatterContext context)
{
var request = context.ActionContext.HttpContext.Request;
var encoding = MatchAcceptCharacterEncoding(request.AcceptCharset);
if (encoding == null)
{
// Match based on request acceptHeader.
var requestContentType = MediaTypeHeaderValue.Parse(request.ContentType);
if (requestContentType != null && !string.IsNullOrEmpty(requestContentType.Charset))
{
var requestCharset = requestContentType.Charset;
encoding = SupportedEncodings.FirstOrDefault(
supportedEncoding =>
requestCharset.Equals(supportedEncoding.WebName));
}
}
encoding = encoding ?? SupportedEncodings.FirstOrDefault();
return(encoding);
}
/// <summary>
/// Sets the default headers for content that will be formatted using this formatter. This method
/// is called from the <see cref="ObjectContent"/> constructor.
/// This implementation sets the Content-Type header to the value of <paramref name="mediaType"/> if it is
/// not <c>null</c>. If it is <c>null</c> it sets the Content-Type to the default media type of this formatter.
/// If the Content-Type does not specify a charset it will set it using this formatters configured
/// <see cref="Encoding"/>.
/// </summary>
/// <remarks>
/// Subclasses can override this method to set content headers such as Content-Type etc. Subclasses should
/// call the base implementation. Subclasses should treat the passed in <paramref name="mediaType"/> (if not <c>null</c>)
/// as the authoritative media type and use that as the Content-Type.
/// </remarks>
/// <param name="type">The type of the object being serialized. See <see cref="ObjectContent"/>.</param>
/// <param name="headers">The content headers that should be configured.</param>
/// <param name="mediaType">The authoritative media type. Can be <c>null</c>.</param>
public virtual void SetDefaultContentHeaders(Type type, HttpContentHeaders headers, string mediaType)
{
if (type == null)
{
throw new ArgumentNullException("type");
}
if (headers == null)
{
throw new ArgumentNullException("headers");
}
if (!String.IsNullOrEmpty(mediaType))
{
var parsedMediaType = MediaTypeHeaderValue.Parse(mediaType);
headers.ContentType = parsedMediaType;
}
// If content type is not set then set it based on supported media types.
if (headers.ContentType == null)
{
MediaTypeHeaderValue defaultMediaType = SupportedMediaTypes.FirstOrDefault();
if (defaultMediaType != null)
{
headers.ContentType = defaultMediaType.Clone();
}
}
// If content type charset parameter is not set then set it based on the supported encodings.
if (headers.ContentType != null && headers.ContentType.CharSet == null)
{
Encoding defaultEncoding = SupportedEncodings.FirstOrDefault();
if (defaultEncoding != null)
{
headers.ContentType.CharSet = defaultEncoding.WebName;
}
}
}
/// <summary>
/// Sets the default headers for content that will be formatted using this formatter. This method
/// is called from the <see cref="ObjectContent"/> constructor.
/// This implementation sets the Content-Type header to the value of <paramref name="mediaType"/> if it is
/// not <c>null</c>. If it is <c>null</c> it sets the Content-Type to the default media type of this formatter.
/// If the Content-Type does not specify a charset it will set it using this formatters configured
/// <see cref="Encoding"/>.
/// </summary>
/// <remarks>
/// Subclasses can override this method to set content headers such as Content-Type etc. Subclasses should
/// call the base implementation. Subclasses should treat the passed in <paramref name="mediaType"/> (if not <c>null</c>)
/// as the authoritative media type and use that as the Content-Type.
/// </remarks>
/// <param name="type">The type of the object being serialized. See <see cref="ObjectContent"/>.</param>
/// <param name="headers">The content headers that should be configured.</param>
/// <param name="mediaType">The authoritative media type. Can be <c>null</c>.</param>
public virtual void SetDefaultContentHeaders(Type type, HttpContentHeaders headers, MediaTypeHeaderValue mediaType)
{
if (type == null)
{
throw Error.ArgumentNull("type");
}
if (headers == null)
{
throw Error.ArgumentNull("headers");
}
if (mediaType != null)
{
headers.ContentType = mediaType.Clone();
}
// If content type is not set then set it based on supported media types.
if (headers.ContentType == null)
{
MediaTypeHeaderValue defaultMediaType = SupportedMediaTypes.FirstOrDefault();
if (defaultMediaType != null)
{
headers.ContentType = defaultMediaType.Clone();
}
}
// If content type charset parameter is not set then set it based on the supported encodings.
if (headers.ContentType != null && headers.ContentType.CharSet == null)
{
Encoding defaultEncoding = SupportedEncodings.FirstOrDefault();
if (defaultEncoding != null)
{
headers.ContentType.CharSet = defaultEncoding.WebName;
}
}
}