private async Task WriteFeedAsync(IEnumerable enumerable, IEdmTypeReference feedType, ODataWriter writer,
ODataSerializerContext writeContext)
{
Contract.Assert(writer != null);
Contract.Assert(writeContext != null);
Contract.Assert(enumerable != null);
Contract.Assert(feedType != null);
IEdmStructuredTypeReference elementType = GetResourceType(feedType);
if (elementType.IsComplex())
{
ODataResourceSet resourceSet = new ODataResourceSet()
{
TypeName = feedType.FullName()
};
await writer.WriteStartAsync(resourceSet).ConfigureAwait(false);
ODataResourceSerializer entrySerializer = SerializerProvider.GetEdmTypeSerializer(elementType) as ODataResourceSerializer;
if (entrySerializer == null)
{
throw new SerializationException(
Error.Format(SRResources.TypeCannotBeSerialized, elementType.FullName()));
}
foreach (object entry in enumerable)
{
await entrySerializer.WriteDeltaObjectInlineAsync(entry, elementType, writer, writeContext).ConfigureAwait(false);
}
}
else
{
ODataDeltaResourceSet deltaFeed = CreateODataDeltaFeed(enumerable, feedType.AsCollection(), writeContext);
if (deltaFeed == null)
{
throw new SerializationException(Error.Format(SRResources.CannotSerializerNull, DeltaFeed));
}
// save the next page link for later to support JSON odata.streaming.
Func <object, Uri> nextLinkGenerator = GetNextLinkGenerator(deltaFeed, enumerable, writeContext);
deltaFeed.NextPageLink = null;
//Start writing of the Delta Feed
await writer.WriteStartAsync(deltaFeed).ConfigureAwait(false);
object lastResource = null;
//Iterate over all the entries present and select the appropriate write method.
//Write method creates ODataDeltaDeletedEntry / ODataDeltaDeletedLink / ODataDeltaLink or ODataEntry.
foreach (object entry in enumerable)
{
if (entry == null)
{
throw new SerializationException(SRResources.NullElementInCollection);
}
lastResource = entry;
IEdmChangedObject edmChangedObject = entry as IEdmChangedObject;
if (edmChangedObject == null)
{
throw new SerializationException(Error.Format(
SRResources.CannotWriteType, GetType().Name, enumerable.GetType().FullName));
}
switch (edmChangedObject.DeltaKind)
{
case EdmDeltaEntityKind.DeletedEntry:
await WriteDeltaDeletedEntryAsync(entry, writer, writeContext).ConfigureAwait(false);
break;
case EdmDeltaEntityKind.DeletedLinkEntry:
await WriteDeltaDeletedLinkAsync(entry, writer, writeContext).ConfigureAwait(false);
break;
case EdmDeltaEntityKind.LinkEntry:
await WriteDeltaLinkAsync(entry, writer, writeContext).ConfigureAwait(false);
break;
case EdmDeltaEntityKind.Entry:
{
ODataResourceSerializer entrySerializer = SerializerProvider.GetEdmTypeSerializer(elementType) as ODataResourceSerializer;
if (entrySerializer == null)
{
throw new SerializationException(
Error.Format(SRResources.TypeCannotBeSerialized, elementType.FullName()));
}
await entrySerializer.WriteDeltaObjectInlineAsync(entry, elementType, writer, writeContext)
.ConfigureAwait(false);
break;
}
default:
break;
}
}
// Subtle and surprising behavior: If the NextPageLink property is set before calling WriteStart(feed),
// the next page link will be written early in a manner not compatible with odata.streaming=true. Instead, if
// the next page link is not set when calling WriteStart(feed) but is instead set later on that feed
// object before calling WriteEnd(), the next page link will be written at the end, as required for
// odata.streaming=true support.
deltaFeed.NextPageLink = nextLinkGenerator(lastResource);
}
//End Writing of the Delta Feed
await writer.WriteEndAsync().ConfigureAwait(false);
}
public virtual ODataOperation CreateODataOperation(IEdmOperation operation, ResourceSetContext resourceSetContext, ODataSerializerContext writeContext)
{
if (operation == null)
{
throw Error.ArgumentNull("operation");
}
if (resourceSetContext == null)
{
throw Error.ArgumentNull("resourceSetContext");
}
if (writeContext == null)
{
throw Error.ArgumentNull("writeContext");
}
ODataMetadataLevel metadataLevel = writeContext.MetadataLevel;
IEdmModel model = writeContext.Model;
if (metadataLevel != ODataMetadataLevel.FullMetadata)
{
return(null);
}
OperationLinkBuilder builder;
builder = model.GetOperationLinkBuilder(operation);
if (builder == null)
{
return(null);
}
Uri target = builder.BuildLink(resourceSetContext);
if (target == null)
{
return(null);
}
Uri baseUri = new Uri(writeContext.Url.CreateODataLink(MetadataSegment.Instance));
Uri metadata = new Uri(baseUri, "#" + operation.FullName());
ODataOperation odataOperation;
IEdmAction action = operation as IEdmAction;
if (action != null)
{
odataOperation = new ODataAction();
}
else
{
odataOperation = new ODataFunction();
}
odataOperation.Metadata = metadata;
// Always omit the title in minimal/no metadata modes.
ODataResourceSerializer.EmitTitle(model, operation, odataOperation);
// Omit the target in minimal/no metadata modes unless it doesn't follow conventions.
if (metadataLevel == ODataMetadataLevel.FullMetadata || !builder.FollowsConventions)
{
odataOperation.Target = target;
}
return(odataOperation);
}
private async Task WriteFeed(IEnumerable enumerable, IEdmTypeReference feedType, ODataDeltaWriter writer,
ODataSerializerContext writeContext)
{
Contract.Assert(writer != null);
Contract.Assert(writeContext != null);
Contract.Assert(enumerable != null);
Contract.Assert(feedType != null);
ODataDeltaResourceSet deltaFeed = CreateODataDeltaFeed(enumerable, feedType.AsCollection(), writeContext);
if (deltaFeed == null)
{
throw new SerializationException(Error.Format(SRResources.CannotSerializerNull, DeltaFeed));
}
// save this for later to support JSON odata.streaming.
Uri nextPageLink = deltaFeed.NextPageLink;
deltaFeed.NextPageLink = null;
//Start writing of the Delta Feed
writer.WriteStart(deltaFeed);
//Iterate over all the entries present and select the appropriate write method.
//Write method creates ODataDeltaDeletedEntry / ODataDeltaDeletedLink / ODataDeltaLink or ODataEntry.
foreach (object entry in enumerable)
{
if (entry == null)
{
throw new SerializationException(SRResources.NullElementInCollection);
}
IEdmChangedObject edmChangedObject = entry as IEdmChangedObject;
if (edmChangedObject == null)
{
throw new SerializationException(Error.Format(SRResources.CannotWriteType, GetType().Name, enumerable.GetType().FullName));
}
switch (edmChangedObject.DeltaKind)
{
case EdmDeltaEntityKind.DeletedEntry:
WriteDeltaDeletedEntry(entry, writer, writeContext);
break;
case EdmDeltaEntityKind.DeletedLinkEntry:
WriteDeltaDeletedLink(entry, writer, writeContext);
break;
case EdmDeltaEntityKind.LinkEntry:
WriteDeltaLink(entry, writer, writeContext);
break;
case EdmDeltaEntityKind.Entry:
{
IEdmEntityTypeReference elementType = GetEntityType(feedType);
ODataResourceSerializer entrySerializer = SerializerProvider.GetEdmTypeSerializer(writeContext.Context, elementType) as ODataResourceSerializer;
if (entrySerializer == null)
{
throw new SerializationException(
Error.Format(SRResources.TypeCannotBeSerialized, elementType.FullName(), typeof(ODataOutputFormatter).Name));
}
await entrySerializer.WriteDeltaObjectInline(entry, elementType, writer, writeContext);
break;
}
default:
break;
}
}
// Subtle and surprising behavior: If the NextPageLink property is set before calling WriteStart(feed),
// the next page link will be written early in a manner not compatible with odata.streaming=true. Instead, if
// the next page link is not set when calling WriteStart(feed) but is instead set later on that feed
// object before calling WriteEnd(), the next page link will be written at the end, as required for
// odata.streaming=true support.
if (nextPageLink != null)
{
deltaFeed.NextPageLink = nextPageLink;
}
//End Writing of the Delta Feed
writer.WriteEnd();
}
