public async Task DeleteBlobFileAsync(Guid blobFileId)
{
using (var context = new FileUploadDemoContext())
{
var blobFile = await context.Set <BlobFile>().SingleAsync(x => x.BlobFileId == blobFileId);
context.Set <BlobFile>().Remove(blobFile);
await context.SaveChangesAsync();
}
}
private static IEnumerable <Stream> GetBlobStreams(Guid blobFileId, IEnumerable <int> chunks)
{
foreach (var chunkId in chunks)
{
using (var context = new FileUploadDemoContext())
{
var chunk = context.Set <BlobFileChunks>().Single(x => x.BlobFileId == blobFileId && x.ChunkId == chunkId);
yield return(new MemoryStream(chunk.Data));
}
}
}
public async Task AddBlobFileChunkAsync(Guid blobFileId, int chunkId, byte[] data)
{
var chunk = new BlobFileChunks
{
BlobFileId = blobFileId,
ChunkId = chunkId,
Length = data.Length,
Data = data
};
using (var context = new FileUploadDemoContext())
{
context.Set <BlobFileChunks>().Add(chunk);
await context.SaveChangesAsync();
}
}
public async Task SaveFileAsAsync(Guid blobFileId, string fileName)
{
List <int> chunks;
using (var context = new FileUploadDemoContext())
chunks = await context.Set <BlobFileChunks>().Where(x => x.BlobFileId == blobFileId).OrderBy(x => x.ChunkId).Select(x => x.ChunkId).ToListAsync();
if (File.Exists(fileName))
{
File.Delete(fileName);
}
using (var file = File.OpenWrite(fileName))
using (var stream = new MultiStream(GetBlobStreams(blobFileId, chunks)))
stream.CopyTo(file);
}
public async Task <IEnumerable <BlobFileInfo> > GetBlobFilesAsync()
{
using (var context = new FileUploadDemoContext())
{
var result = await context.Set <BlobFile>().OrderBy(x => x.CreatedOn).ToListAsync();
return(result.Select(x => new BlobFileInfo
{
BlobFileId = x.BlobFileId,
Name = x.Name,
Description = x.Description,
Size = x.Size,
CreatedBy = x.CreatedBy,
CreatedOn = x.CreatedOn
}));
}
}
public async Task <string> ProcessFileAsync(Guid blobFileId)
{
List <int> chunks;
using (var context = new FileUploadDemoContext())
chunks = await context.Set <BlobFileChunks>().Where(x => x.BlobFileId == blobFileId).OrderBy(x => x.ChunkId).Select(x => x.ChunkId).ToListAsync();
var result = 0;
using (var stream = new MultiStream(GetBlobStreams(blobFileId, chunks)))
{
foreach (var chunk in stream.GetByteChunks(1024))
{
result = (result * 31) ^ ComputeHash(chunk);
}
}
return(string.Format("File Hash Code is: {0}", result));
}
public async Task <Guid> CreateBlobFileAsync(string name, string description, long size, string createdBy)
{
var blobFile = new BlobFile
{
BlobFileId = Guid.NewGuid(),
Name = name,
Description = description,
Size = size,
CreatedBy = createdBy,
CreatedOn = DateTime.UtcNow
};
using (var context = new FileUploadDemoContext())
{
context.Set <BlobFile>().Add(blobFile);
await context.SaveChangesAsync();
}
return(blobFile.BlobFileId);
}
