Benevia.Core.Blobs 0.9.16

Benevia.Core.Blobs

Maintainers

• @jamers99

Introduction

Provides blob storage capabilities for the Benevia Core platform, supporting both Azure Blob Storage and local file system storage. Offers secure URL generation for direct client uploads/downloads as well as getting the blob as Base64 strings.

Setup

Configure blob storage provider in your DI container:

Azure Blob Storage:

services.AddCoreBlobsAzure(options =>
{
    options.StorageAccountUri = new Uri("https://mystorageaccount.blob.core.windows.net");
    options.Credentials = new ManagedIdentityCredential(); //see https://learn.microsoft.com/en-us/dotnet/azure/sdk/authentication/system-assigned-managed-identity for set up
});

In Azure, ensure the identity has the Storage Blob Delegator and Storage Blob Data Contributor permissions. The urls returned will require a Content-Type and BlockBlob: 'BlockBlob' header.

Local File Storage:

services.AddCoreBlobsLocal(options =>
{
    options.StorageDirectory = @"C:\BlobStorage";
});

Usage

1. Add the Blob entity in your model:

[ApiEntity]
public partial class Product
{
    // ...

    [ReferenceProperty("Image", DeleteAction.SetNull, ReferenceType.OneToOne,
        Description = "An image of the product")]
    public virtual partial Blob? Image { get; set; }

    // ...
}

2. Use via OData API:

Create a Product with an Image Blob:

POST /api/Product?$select=Guid&$expand=Image($select=UploadUrl)
Content-Type: application/json

{
  "Sku": "PRODUCT-123",
  "Image": {
    "Name": "product-image.png"
  }
}

Upload Image:

Azure Blob Storage:

PUT {UploadUrl from previous response}
Content-Type: image/png
x-ms-blob-type: BlockBlob

{binary image data}

Local Storage: Local storage supports both POST and PUT methods. You can upload using multipart/form-data or by sending the binary content directly in the body.

PUT {UploadUrl from previous response}
Content-Type: image/png

{binary image data}

Retrieve Image in Base64 format:

GET /api/Product({Guid})?$select=Guid,Image&$expand=Image($select=Base64Content,DownloadUrl,Name)

Download Image:

GET {DownloadUrl from previous response}

Notes

<details> The Blob entity provides virtual properties for download URLs, upload URLs, and Base64 content that are computed through the configured blob provider. Supports both direct streaming through URLs and content as Base64-encoded string. </details>