/// <inheritdoc/>
public override bool CanWriteType(Type type)
{
if (type == null)
{
throw Error.ArgumentNull("type");
}
if (Request != null)
{
ODataSerializerProvider serializerProvider = Request.GetRequestContainer()
.GetRequiredService <ODataSerializerProvider>();
// See if this type is a SingleResult or is derived from SingleResult.
bool isSingleResult = false;
if (type.IsGenericType)
{
Type genericType = type.GetGenericTypeDefinition();
Type baseType = TypeHelper.GetBaseType(type);
isSingleResult = (genericType == typeof(SingleResult <>) || baseType == typeof(SingleResult));
}
return(ODataOutputFormatterHelper.CanWriteType(
type,
_payloadKinds,
isSingleResult,
new WebApiRequestMessage(Request),
(objectType) => serializerProvider.GetODataPayloadSerializer(objectType, Request)));
}
return(false);
}
/// <inheritdoc/>
public override bool CanWriteResult(OutputFormatterCanWriteContext context)
{
if (context == null)
{
throw Error.ArgumentNull("context");
}
// Ensure we have a valid request.
HttpRequest request = context.HttpContext.Request;
if (request == null)
{
throw Error.InvalidOperation(SRResources.ReadFromStreamAsyncMustHaveRequest);
}
// Ignore non-OData requests.
if (request.ODataFeature().Path == null)
{
return(false);
}
// The following base.CanWriteResult(context) will change the context.ContentType
// If this formatter can't write the result, we should reset the context.ContentType to its original value.
// So that, the other formatter can make a descison based on the original content type.
// Be noted: in .NET 5, the context.ContentType is a new StringSegment everytime when goes into each formatter
// formatterContext.ContentType = new StringSegment();
// So, in .NET 5, we don't need to reset the contentType to backupContentType.
StringSegment backupContentType = context.ContentType;
// Allow the base class to make its determination, which includes
// checks for SupportedMediaTypes.
bool suportedMediaTypeFound = false;
if (SupportedMediaTypes.Any())
{
suportedMediaTypeFound = base.CanWriteResult(context);
}
// See if the request satisfies any mappings.
IEnumerable <MediaTypeMapping> matchedMappings = (MediaTypeMappings == null) ? null : MediaTypeMappings
.Where(m => (m.TryMatchMediaType(request) > 0));
// Now pick the best content type. If a media mapping was found, use that and override the
// value specified by the controller, if any. Otherwise, let the base class decide.
if (matchedMappings != null && matchedMappings.Any())
{
context.ContentType = matchedMappings.First().MediaType.ToString();
}
else if (!suportedMediaTypeFound)
{
context.ContentType = backupContentType;
return(false);
}
// We need the type in order to write it.
Type type = context.ObjectType ?? context.Object?.GetType();
if (type == null)
{
context.ContentType = backupContentType;
return(false);
}
type = TypeHelper.GetTaskInnerTypeOrSelf(type);
ODataSerializerProvider serializerProvider = request.GetRequestContainer().GetRequiredService <ODataSerializerProvider>();
// See if this type is a SingleResult or is derived from SingleResult.
bool isSingleResult = false;
if (type.IsGenericType)
{
Type genericType = type.GetGenericTypeDefinition();
Type baseType = TypeHelper.GetBaseType(type);
isSingleResult = (genericType == typeof(SingleResult <>) || baseType == typeof(SingleResult));
}
bool result = ODataOutputFormatterHelper.CanWriteType(
type,
_payloadKinds,
isSingleResult,
new WebApiRequestMessage(request),
(objectType) => serializerProvider.GetODataPayloadSerializer(objectType, request));
if (!result)
{
context.ContentType = backupContentType;
}
return(result);
}
