御用小本本

Blob Storing Azure

首先參照官方文件安裝並設定 Azure Storage

Blob Storing Azure | Documentation Center | ABP.IO

我是把 volo.abp.blobstoring.azure 套件裝在 Domain 層

然後把 Azure Storage 連接字串設定在 HttpApi.Host (Web)

Save

基本用法請參考以下文件

Blob Storing | Documentation Center | ABP.IO

範例

SaveImagesAsync (Application)

public async Task SaveImageAsync([FromForm]SaveImageDto input)
{
    var fromFile = input.FormFile;
    await using var stream = fromFile.OpenReadStream();
    await _blobContainer.SaveAsync(fromFile.FileName, stream);
}

• 如果不是直接輸入 IFormFile 則要記得加 [FromForm]
• SaveAsync 可以輸入 stream
• OpenReadStream 記得 using 不然可能要自己 close ?

SaveImageDto (Application.Contracts)

public class SaveImageDto : IValidatableObject
{
    [Required]
    public IFormFile FormFile { get; set; }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        if (!StorageHelper.IsImage(FormFile))
        {
            yield return new ValidationResult(
                "Extension must be .jpg, .png, .gif, .jpeg!",
                new[] { "FormFile" }
            );
        }
    }
}

• IValidatableObject 會自動驗證輸入資料，需實作 Validate
  Validation | Documentation Center | ABP.IO
• ValidationResult 第一個參數是 message，可以自己調整
• StorageHelper 這個類要自己建出來，如下所示

Application.Contracts.Helpers.StorageHelper.cs

public static bool IsImage(IFormFile file)
{
  if (file.ContentType.Contains("image"))
  {
     return true;
  }

  string[] formats = new string[] { ".jpg", ".png", ".gif", ".jpeg" };

  return formats.Any(item => file.FileName.EndsWith(item, StringComparison.OrdinalIgnoreCase));
}

• 檢查 ContentType 或是副檔名是否合乎規定
• 如果不要 .gif 可以自己從 formats 拿掉

storage-blob-upload-from-webapp/StorageHelper.cs at master · Azure-Samples/storage-blob-upload-from-webapp (github.com)

Get

public async Task<IRemoteStreamContent> GetImageAsync(string name)
{
    var fs = await _blobContainer.GetAsync(name);
    fs.Position = 0;
    if (!_contentTypeProvider.TryGetContentType(name, out var contentType))
    {
        contentType = "application/octet-stream";
    }
    return new RemoteStreamContent(fs,name,contentType);
}

• fs.Position = 0; => 不加這行會不能下載，是不是 Bug 我不知道，但絕對是個坑！
  How to user IRemoteStreamContent with BLOB Storing Azure Provider · Issue #7418 · abpframework/abp (github.com)
• IContentTypeProvider => 這邊DI FileExtensionContentTypeProvider 來判斷 ContentType

public class YourProjectApplicationModule : AbpModule
{
    public override void ConfigureServices(ServiceConfigurationContext context)
    {
        context.Services.AddSingleton<IContentTypeProvider, FileExtensionContentTypeProvider>();
    }
}

如果不管 ContentType 那就改成以下這樣也就不用設定 DI 了

return new RemoteStreamContent(fs,name,"application/octet-stream");

參照

Application Services | Documentation Center | ABP.IO

File Upload/Download with BLOB Storage System in ASP.NET Core & ABP Framework | ABP Community

備註

如果無法儲存可能要去 Azure 手動建立 container

名稱需與設定一致 azure.ContainerName = "your azure container name"; 

單元測試

剛測試發現整合測試其他 API 過不了

到 TestBase 設定 DI 可以先正常測試

test\YourProject.TestBase.YourProjectTestBaseModule.cs

public override void ConfigureServices(ServiceConfigurationContext context)
{
    Configure<AbpBlobStoringOptions>(options =>
    {
        options.Containers.ConfigureDefault(container =>
        {
            container.UseAzure(azure =>
            {
                azure.ConnectionString = "your azure connection string";
                azure.ContainerName = "your azure container name";
                azure.CreateContainerIfNotExists = true;
            });
        });
    });
}

// TODO: context.Services.Replace(ServiceDescriptor.Singleton<IBlobContainer, NullBlobContainer>());