/// <summary>
/// Creates a thumbnail image of a file in the storage.
/// </summary>
/// <param name="originalMetadataId">Metadata entry ID for the original image file.</param>
/// <param name="maxWidth">Maximum width of the thumbnail image.</param>
/// <param name="maxHeight">Maximum height of the thumbnail image.</param>
/// <param name="sourceFullStorageFileName">Name of the source image file.</param>
/// <param name="thumbFullStorageFileName">Name of the thumbnail image cache file.</param>
/// <param name="loadFromCache">Whether to use a cached thumbnail or not.</param>
/// <param name="storage">Storage service used to get file data.</param>
/// <param name="fileMetadataProvider">File metadata provider used to create thumbnail image metadata.</param>
/// <returns>Returns the result of the thumbnail creation process.</returns>
public static CreateThumbResult TryGetOrCreateThumb(
int originalMetadataId,
int maxWidth,
int maxHeight,
string sourceFullStorageFileName,
string thumbFullStorageFileName,
bool loadFromCache,
IBlobStorageManager storage,
IFileMetadataProvider fileMetadataProvider)
{
var srcBlobLocation = new BlobLocation(sourceFullStorageFileName);
var thumbBlobLocation = new BlobLocation(thumbFullStorageFileName);
if (loadFromCache && !string.IsNullOrEmpty(thumbFullStorageFileName))
{
var thumbStream = storage.DownloadFileFromStorage(thumbBlobLocation);
if (thumbStream != null)
{
using (thumbStream)
using (var stream = new MemoryStream((int)thumbStream.Length))
{
thumbStream.CopyTo(stream);
{
return new CreateThumbResult(
CreateThumbStatus.Ok,
stream.ToArray(),
MimeTypesHelper.GetContentType(Path.GetExtension(thumbFullStorageFileName)));
}
}
}
}
if (!StringHelper.IsImageFileName(sourceFullStorageFileName))
return new CreateThumbResult(CreateThumbStatus.SourceIsNotImage, null, null);
var srcStream = storage.DownloadFileFromStorage(srcBlobLocation);
if (srcStream == null)
return new CreateThumbResult(CreateThumbStatus.SourceFileNotFound, null, null);
string contentType;
byte[] array;
using (srcStream)
using (var srcImage = Image.FromStream(srcStream))
{
var imageSizeMegabytes = srcImage.Width * srcImage.Height * 4 / 1024000.0;
if (imageSizeMegabytes > 40.0)
return new CreateThumbResult(CreateThumbStatus.SourceImageTooLarge, null, null);
using (var newImage = ResizeImage(srcImage, maxWidth, maxHeight, keepAspect: true, canGrow: false))
using (var newStream = new MemoryStream())
{
if (newImage == null)
{
srcStream.Position = 0;
srcStream.CopyTo(newStream);
contentType = MimeTypesHelper.GetContentType(Path.GetExtension(sourceFullStorageFileName));
}
else
{
var imageFormat = (newImage.Width * newImage.Height > 10000)
? ImageFormat.Jpeg
: ImageFormat.Png;
contentType = (newImage.Width * newImage.Height > 10000)
? "image/jpeg"
: "image/png";
newImage.Save(newStream, imageFormat);
}
array = newStream.ToArray();
if (loadFromCache && newImage != null && !string.IsNullOrEmpty(thumbFullStorageFileName))
{
// saving thumbnail image file metadata
var relationType = string.Format("thumb-{0}x{1}", maxWidth, maxHeight);
var metadata = fileMetadataProvider.CreateRelated(
originalMetadataId,
relationType,
thumbBlobLocation.ContainerName,
thumbBlobLocation.FileName,
thumbBlobLocation.BlobName,
null);
fileMetadataProvider.SaveChanges();
storage.UploadFileToStorage(new MemoryStream(array), thumbBlobLocation);
}
}
}
return new CreateThumbResult(CreateThumbStatus.Ok, array, contentType);
}
/// <summary>
/// Downloads a file from the Windows Azure Storage.
/// </summary>
/// <param name="this">Blob storage manager to use.</param>
/// <param name="location">Location of the blob to download.</param>
/// <returns>Returns a valid stream that can be used to read file data, or null if the file does not exist.</returns>
public static Stream DownloadFileFromStorage(this IBlobStorageManager @this, BlobLocation location)
{
return(@this.DownloadFileFromStorage(location.ContainerName, location.BlobName));
}
/// <summary>
/// Creates a thumbnail image of a file in the storage.
/// </summary>
/// <param name="originalMetadataId">Metadata entry ID for the original image file.</param>
/// <param name="maxWidth">Maximum width of the thumbnail image.</param>
/// <param name="maxHeight">Maximum height of the thumbnail image.</param>
/// <param name="sourceFullStorageFileName">Name of the source image file.</param>
/// <param name="thumbFullStorageFileName">Name of the thumbnail image cache file.</param>
/// <param name="loadFromCache">Whether to use a cached thumbnail or not.</param>
/// <param name="storage">Storage service used to get file data.</param>
/// <param name="fileMetadataProvider">File metadata provider used to create thumbnail image metadata.</param>
/// <returns>Returns the result of the thumbnail creation process.</returns>
public static CreateThumbResult TryGetOrCreateThumb(
int originalMetadataId,
int maxWidth,
int maxHeight,
string sourceFullStorageFileName,
string thumbFullStorageFileName,
bool loadFromCache,
IBlobStorageManager storage,
IFileMetadataProvider fileMetadataProvider)
{
var srcBlobLocation = new BlobLocation(sourceFullStorageFileName);
var thumbBlobLocation = new BlobLocation(thumbFullStorageFileName);
if (loadFromCache && !string.IsNullOrEmpty(thumbFullStorageFileName))
{
var thumbStream = storage.DownloadFileFromStorage(thumbBlobLocation);
if (thumbStream != null)
{
using (thumbStream)
using (var stream = new MemoryStream((int)thumbStream.Length))
{
thumbStream.CopyTo(stream);
{
return(new CreateThumbResult(
CreateThumbStatus.Ok,
stream.ToArray(),
MimeTypesHelper.GetContentType(Path.GetExtension(thumbFullStorageFileName))));
}
}
}
}
if (!StringHelper.IsImageFileName(sourceFullStorageFileName))
{
return(new CreateThumbResult(CreateThumbStatus.SourceIsNotImage, null, null));
}
var srcStream = storage.DownloadFileFromStorage(srcBlobLocation);
if (srcStream == null)
{
return(new CreateThumbResult(CreateThumbStatus.SourceFileNotFound, null, null));
}
string contentType;
byte[] array;
using (srcStream)
using (var srcImage = Image.FromStream(srcStream))
{
var imageSizeMegabytes = srcImage.Width * srcImage.Height * 4 / 1024000.0;
if (imageSizeMegabytes > 40.0)
{
return(new CreateThumbResult(CreateThumbStatus.SourceImageTooLarge, null, null));
}
using (var newImage = ResizeImage(srcImage, maxWidth, maxHeight, keepAspect: true, canGrow: false))
using (var newStream = new MemoryStream())
{
if (newImage == null)
{
srcStream.Position = 0;
srcStream.CopyTo(newStream);
contentType = MimeTypesHelper.GetContentType(Path.GetExtension(sourceFullStorageFileName));
}
else
{
var imageFormat = (newImage.Width * newImage.Height > 10000)
? ImageFormat.Jpeg
: ImageFormat.Png;
contentType = (newImage.Width * newImage.Height > 10000)
? "image/jpeg"
: "image/png";
newImage.Save(newStream, imageFormat);
}
array = newStream.ToArray();
if (loadFromCache && newImage != null && !string.IsNullOrEmpty(thumbFullStorageFileName))
{
// saving thumbnail image file metadata
var relationType = string.Format("thumb-{0}x{1}", maxWidth, maxHeight);
var metadata = fileMetadataProvider.CreateRelated(
originalMetadataId,
relationType,
thumbBlobLocation.ContainerName,
thumbBlobLocation.FileName,
thumbBlobLocation.BlobName,
null);
fileMetadataProvider.SaveChanges();
storage.UploadFileToStorage(new MemoryStream(array), thumbBlobLocation);
}
}
}
return(new CreateThumbResult(CreateThumbStatus.Ok, array, contentType));
}