آموزش ذخیره سازی Azure Blob در Asp.Net MVC Core

Azure Blob Storage In ASP.NET Core 2.0

Problem

نحوه استفاده از ذخیره سازی Azure Blob در ASP.NET Core.

Solution

یک class library ایجاد کنید و NuGet package - WindowsAzure.Storage را اضافه کنید.

یک کلاس برای تنظیم کردن تنظیمات اضافه کنید:

public class AzureBlobSetings  
 {  
     public AzureBlobSetings(string storageAccount,  
                                    string storageKey,  
                                    string containerName)  
     {  
         if (string.IsNullOrEmpty(storageAccount))  
             throw new ArgumentNullException("StorageAccount");  
  
         if (string.IsNullOrEmpty(storageKey))  
             throw new ArgumentNullException("StorageKey");  
  
         if (string.IsNullOrEmpty(containerName))  
             throw new ArgumentNullException("ContainerName");  
  
         this.StorageAccount = storageAccount;  
         this.StorageKey = storageKey;  
         this.ContainerName = containerName;  
     }  
  
     public string StorageAccount { get; }  
     public string StorageKey { get; }  
     public string ContainerName { get; }  
 }

یک کلاس برای تنظیم کردن blob item اضافه کنید:

public class AzureBlobItem  
  {  
      public AzureBlobItem(IListBlobItem item)  
      {  
          this.Item = item;  
      }  
  
      public IListBlobItem Item { get; }  
  
      public bool IsBlockBlob => Item.GetType() == typeof(CloudBlockBlob);  
      public bool IsPageBlob => Item.GetType() == typeof(CloudPageBlob);  
      public bool IsDirectory => Item.GetType() == typeof(CloudBlobDirectory);  
  
      public string BlobName => IsBlockBlob ? ((CloudBlockBlob)Item).Name :  
                                IsPageBlob ? ((CloudPageBlob)Item).Name :  
                                IsDirectory ? ((CloudBlobDirectory)Item).Prefix :  
                                "";  
  
      public string Folder => BlobName.Contains("/") ?  
                       BlobName.Substring(0, BlobName.LastIndexOf("/")) : "";  
  
      public string Name => BlobName.Contains("/") ?  
                       BlobName.Substring(BlobName.LastIndexOf("/") + 1) : BlobName;  
  }

یک کلاس برای دسترسی به ذخیره سازی اضافه کنید. برای دسترسی به ذخیره سازی یک private helper methods را اضافه کنید.

  private async Task< CloudBlobContainer > GetContainerAsync()  
        {  
            //Account  
            CloudStorageAccount storageAccount = new CloudStorageAccount(  
         new StorageCredentials(settings.StorageAccount, settings.StorageKey), false);  
   
            //Client  
            CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();  
   
            //Container  
            CloudBlobContainer blobContainer =  
blobClient.GetContainerReference(settings.ContainerName);  
            await blobContainer.CreateIfNotExistsAsync();  
   
            return blobContainer;  
        }  
   
        private async Task< CloudBlockBlob > GetBlockBlobAsync(string blobName)  
        {  
            //Container  
            CloudBlobContainer blobContainer = await GetContainerAsync();  
   
            //Blob  
            CloudBlockBlob blockBlob = blobContainer.GetBlockBlobReference(blobName);  
   
            return blockBlob;  
        }  
   
        private async Task< List < AzureBlobItem > > GetBlobListAsync(
bool useFlatListing = true)
        {
            //Container
            CloudBlobContainer blobContainer = await GetContainerAsync();

            //List
            var list = new List< AzureBlobItem >();
            BlobContinuationToken token = null;
            do
            {
                BlobResultSegment resultSegment =
                    await blobContainer.ListBlobsSegmentedAsync("", useFlatListing,
new BlobListingDetails(), null, token, null, null);
                token = resultSegment.ContinuationToken;

                foreach (IListBlobItem item in resultSegment.Results)
                {
                    list.Add(new AzureBlobItem(item));
                }
            } while (token != null);

            return list.OrderBy(i => i.Folder).ThenBy(i => i.Name).ToList();
        }

می توانیم اکنون برای upload و download (موارد blob items) از public methods ها استفاده کنیم:

public async Task UploadAsync(string blobName, string filePath)  
      {  
          //Blob  
          CloudBlockBlob blockBlob = await GetBlockBlobAsync(blobName);  
  
          //Upload  
          using (var fileStream = System.IO.File.Open(filePath, FileMode.Open))  
          {  
              fileStream.Position = 0;  
              await blockBlob.UploadFromStreamAsync(fileStream);  
          }  
      }  
  
      public async Task UploadAsync(string blobName, Stream stream)  
      {  
          //Blob  
          CloudBlockBlob blockBlob = await GetBlockBlobAsync(blobName);  
  
          //Upload  
          stream.Position = 0;  
          await blockBlob.UploadFromStreamAsync(stream);  
      }  
  
      public async Task< MemoryStream > DownloadAsync(string blobName)  
      {  
          //Blob  
          CloudBlockBlob blockBlob = await GetBlockBlobAsync(blobName);  
  
          //Download  
          using (var stream = new MemoryStream())  
          {  
              await blockBlob.DownloadToStreamAsync(stream);  
              return stream;  
          }  
      }  
  
      public async Task DownloadAsync(string blobName, string path)  
      {  
          //Blob  
          CloudBlockBlob blockBlob = await GetBlockBlobAsync(blobName);  
  
          //Download  
          await blockBlob.DownloadToFileAsync(path, FileMode.Create);  
      }

متدی برای گرفتن لیستی از blob items را اضافه می کنیم:

public async Task< List< AzureBlobItem > > ListAsync()
   {
       return await GetBlobListAsync();
   }

   public async Task< List< string > > ListFoldersAsync()
   {
       var list = await GetBlobListAsync();
       return list.Where(i => !string.IsNullOrEmpty(i.Folder))
                  .Select(i => i.Folder)
                  .Distinct()
                  .OrderBy(i => i)
                  .ToList();
   }

تزریق(Inject) و استفاده از storage helper:

public class HomeController : Controller  
  {  
      private readonly IAzureBlobStorage blobStorage;  
  
      public HomeController(IAzureBlobStorage blobStorage)  
      {  
          this.blobStorage = blobStorage;  
      }

نکته:

این کدها دارای یک کنترلر با اکشن هایی برای listing ، downloading و uploading است.

در ASP.NET Core Web Application، configure services:

public void ConfigureServices(  
        IServiceCollection services)  
    {  
        services.AddScoped< IAzureBlobStorage >(factory =>  
        {  
            return new AzureBlobStorage(new AzureBlobSetings(  
                storageAccount: Configuration["Blob_StorageAccount"],  
                storageKey: Configuration["Blob_StorageKey"],  
                containerName: Configuration["Blob_ContainerName"]));  
        });  
  
        services.AddMvc();  
    }