/// <summary>
/// Creates the thumbnail image entity.
/// </summary>
/// <param name="stream">The stream.</param>
/// <param name="originalImageEntity">The original image entity.</param>
/// <param name="fileExtension">The file extension.</param>
/// <param name="width">The width.</param>
/// <param name="height">The height.</param>
/// <param name="scaleEnum">The scale enum.</param>
/// <returns></returns>
private ThumbnailFileType CreateThumbnailImageEntity(Stream stream, ImageFileType originalImageEntity, string fileExtension,
int width, int height, ImageScaleEnum scaleEnum)
{
using (DatabaseContext context = DatabaseContext.GetContext(true))
{
stream.Position = 0;
string dataHash = FileRepositoryHelper.AddTemporaryFile(stream);
var thumbnailEntity = new ThumbnailFileType( );
string thumbnailName = originalImageEntity.Name;
if (string.IsNullOrEmpty(thumbnailName))
{
thumbnailName = "Thumbnail";
}
else
{
thumbnailName += " Thumbnail";
}
thumbnailEntity.Name = thumbnailName;
thumbnailEntity.FileDataHash = dataHash;
thumbnailEntity.FileExtension = fileExtension;
thumbnailEntity.ImageWidth = width;
thumbnailEntity.ImageHeight = height;
thumbnailEntity.ThumbnailScaling = scaleEnum;
thumbnailEntity.IsThumbnailForImage = originalImageEntity;
thumbnailEntity.Save( );
context.CommitTransaction( );
return(thumbnailEntity);
}
}
public ThumbnailViewer(bool visible,bool collapsed,bool showBrowseButton,ThumbnailFileType thumbnailFileType)
{
this._visible = visible;
this._collapsed = collapsed;
this._showBrowseButton = showBrowseButton;
this._thumbnailFileType = thumbnailFileType;
_ctrl = null;
}
public ThumbnailViewer(bool visible, bool collapsed, bool showBrowseButton, ThumbnailFileType thumbnailFileType)
{
this._visible = visible;
this._collapsed = collapsed;
this._showBrowseButton = showBrowseButton;
this._thumbnailFileType = thumbnailFileType;
_ctrl = null;
}
/// <summary>
/// Gets the image thumbnail.
/// </summary>
/// <param name="imageId">The image id.</param>
/// <param name="sizeId">The size id.</param>
/// <param name="scaleId">The scale id.</param>
/// <returns></returns>
/// <exception cref="System.InvalidOperationException">The thumbnail size has invalid dimensions specified.</exception>
public ImageFileType GetImageThumbnail(EntityRef imageId, EntityRef sizeId, EntityRef scaleId)
{
int thumbnailWidth;
int thumbnailHeight;
ImageScaleEnum imageScaleEnum;
ThumbnailSizeEnum thumbnailSizeEnum;
// Quickly fail on invalid IDs
if (_invalidImageIds.ContainsKey(imageId.Id))
{
throw new ArgumentException("The image entity was not found.");
}
// We don't really need to secure thumbnail sizes and image scale in this context.
using (new SecurityBypassContext())
{
// Get the size and scale entities
thumbnailSizeEnum = Entity.Get <ThumbnailSizeEnum>(sizeId);
imageScaleEnum = Entity.Get <ImageScaleEnum>(scaleId);
if (thumbnailSizeEnum == null)
{
throw new ArgumentNullException("Invalid thumbnail size");
}
if (imageScaleEnum == null)
{
throw new ArgumentNullException("Invalid image scale");
}
// Get the width and height from the thumbnail size enum
thumbnailWidth = thumbnailSizeEnum.ThumbnailWidth ?? -1;
thumbnailHeight = thumbnailSizeEnum.ThumbnailHeight ?? -1;
}
if (thumbnailHeight <= 0 || thumbnailWidth <= 0)
{
throw new ArgumentNullException("The thumbnail size has invalid dimensions specified.");
}
// Get the requested image
var originalImageEntity = Entity.Get <ImageFileType>(imageId);
// Handle missing images
if (originalImageEntity == null)
{
// Verify if an admin can access it.
using (new SecurityBypassContext( ))
{
var unsecuredEntity = Entity.Get <ImageFileType>(imageId);
if (unsecuredEntity == null)
{
_invalidImageIds [imageId.Id] = null;
}
}
throw new ArgumentException("The image entity was not found.");
}
// Allow user access to thumbnails if they have access to the image
using (new SecurityBypassContext( ))
{
// SVG can scale themselves fine as they are vector based. No need for thumbs.
if (!string.IsNullOrEmpty(originalImageEntity.FileExtension) &&
originalImageEntity.FileExtension.ToLower().EndsWith(".svg"))
{
return(originalImageEntity);
}
ThumbnailFileType thumbnail;
// Create a thumbnail create key for this combination of image, size and scale.
ThumbnailCreationKey createKey = new ThumbnailCreationKey(originalImageEntity.Id, thumbnailSizeEnum.Id, imageScaleEnum.Id);
ThumbnailCreationValue createValue = null;
try
{
// Get or add a create value
createValue = _activeThumbnailCreations.GetOrAdd(createKey, k => new ThumbnailCreationValue());
// Increment the ref count
createValue.IncrementRefCount();
// Lock on this syncroot.
// Note: we are locking on this create value. This will only block parallel requests for the same image, size and scale combinations.
lock (createValue.SyncRoot)
{
// Find the first thumbnail with a matching size and scale
thumbnail = originalImageEntity.ImageHasThumbnails.FirstOrDefault(tt =>
{
int height = tt.ImageHeight ?? -1;
int width = tt.ImageWidth ?? -1;
if (height == -1 ||
width == -1 ||
width != thumbnailWidth ||
height != thumbnailHeight)
{
// The thumbnail width does not match.
return(false);
}
long thumbnailScalingId = tt.ThumbnailScaling != null ? tt.ThumbnailScaling.Id : -1;
if (thumbnailScalingId == -1 || thumbnailScalingId != imageScaleEnum.Id)
{
// The thumbnail scale does not match.
return(false);
}
return(true);
});
if (thumbnail == null || (string.IsNullOrEmpty(thumbnail.FileDataHash)))
{
using (Stream thumbnailStream = CreateThumbnailImage(originalImageEntity, thumbnailWidth, thumbnailHeight, imageScaleEnum.Alias))
{
// Create the thumbnail entity and add the file to the database
ThumbnailFileType thumbnailFileType = CreateThumbnailImageEntity(thumbnailStream,
originalImageEntity, originalImageEntity.FileExtension,
thumbnailWidth, thumbnailHeight, imageScaleEnum);
return(thumbnailFileType.As <ImageFileType>());
}
}
}
}
finally
{
// Decrement the ref count and remove from the active creations dictionary.
if (createValue != null &&
createValue.DecrementRefCount() <= 0)
{
ThumbnailCreationValue removedValue;
_activeThumbnailCreations.TryRemove(createKey, out removedValue);
}
}
// Found a thumbnail. Return it.
return(thumbnail.As <ImageFileType>());
}
}