/// <summary>
/// Submits a request for execution and returns an IDataSource
/// representing the pending encoded image(s).
///
/// <para />The ResizeOptions in the imageRequest will be
/// ignored for this fetch.
///
/// <para />The returned IDataSource must be closed once the
/// client has finished with it.
/// </summary>
/// <param name="imageRequest">
/// The request to submit.
/// </param>
/// <param name="callerContext">
/// The caller context for image request.
/// </param>
/// <returns>
/// An IDataSource representing the pending encoded image(s).
/// </returns>
public IDataSource <CloseableReference <IPooledByteBuffer> > FetchEncodedImage(
ImageRequest imageRequest,
object callerContext)
{
Preconditions.CheckNotNull(imageRequest.SourceUri);
try
{
IProducer <CloseableReference <IPooledByteBuffer> > producerSequence =
_producerSequenceFactory.GetEncodedImageProducerSequence(imageRequest);
// The resize options are used to determine whether images are going to be
// downsampled during decode or not. For the case where the image has to be
// downsampled and it's a local image it will be kept as a FileStream until
// decoding instead of reading it in memory. Since this method returns an
// encoded image, it should always be read into memory. Therefore, the resize
// options are ignored to avoid treating the image as if it was to be
// downsampled during decode.
if (imageRequest.ResizeOptions != null)
{
imageRequest = ImageRequestBuilder.FromRequest(imageRequest)
.SetResizeOptions(null)
.Build();
}
return(SubmitFetchRequest(
producerSequence,
imageRequest,
new RequestLevel(RequestLevel.FULL_FETCH),
callerContext));
}
catch (Exception exception)
{
return(DataSources.ImmediateFailedDataSource <CloseableReference <IPooledByteBuffer> >(
exception));
}
}