Nexus.Upload 1.0.2

Nexus.Upload

Shared image-upload library for the Nexus microservices (user, catalog, commerce, auction, fulfillment, notification). It validates images and stores them through a pluggable storage provider, chosen automatically from configuration.

• Local (development): saves files to a local directory, served via static files.
• DigitalOcean Spaces (production): S3-compatible object storage via the AWS S3 SDK.

Install

dotnet add package Nexus.Upload

Register

using Nexus.Upload.src.Extensions;

builder.Services.AddNexusUpload(builder.Configuration); // reads the "UploadService" section

Serve locally-stored files (Local provider only):

app.UseStaticFiles(new StaticFileOptions
{
    FileProvider = new PhysicalFileProvider(Path.Combine(app.Environment.ContentRootPath, "uploads")),
    RequestPath = "/uploads"
});

Configuration

The provider is Spaces only when StorageType = "Spaces" and ASPNETCORE_ENVIRONMENT = "Production"; otherwise it falls back to Local.

Development (appsettings.json):

{
  "UploadService": {
    "StorageType": "Local",
    "Local": {
      "BaseDirectory": "uploads",
      "BaseUrl": "http://localhost:8080/uploads"
    }
  }
}

Production — supply secrets via environment variables, never commit them (UploadService__Spaces__AccessKey, ...):

{
  "UploadService": {
    "StorageType": "Spaces",
    "Spaces": {
      "AccessKey": "<spaces-access-key>",
      "SecretKey": "<spaces-secret-key>",
      "BucketName": "my-bucket",
      "Region": "sgp1",
      "Endpoint": "https://sgp1.digitaloceanspaces.com"
    }
  }
}

Spaces keys are created under DigitalOcean → API → Spaces Keys (not the DO API token) and need write access to the bucket. Objects are stored public-read so their URLs are directly viewable; the returned URL is https://{bucket}.{region}.digitaloceanspaces.com/{key}.

Usage

public sealed class AvatarController(UploadService uploadService)
{
    public async Task<IActionResult> Upload(IFormFile file)
    {
        using var ms = new MemoryStream();
        await file.CopyToAsync(ms);

        var result = await uploadService.UploadImageAsync(ms.ToArray(), new UploadOptions
        {
            Service   = "user",
            ImageType = "avatar",
            UserId    = currentUserId,
            FileName  = file.FileName,
            MimeType  = file.ContentType,
            Size      = file.Length
        });

        // result.Url, result.Key, result.Size
        return Ok(result);
    }
}

await uploadService.DeleteImageAsync(key);

Storage key format: {service}/{type}/{userId|shared}/{timestamp}-{filename}.

Image types & validation limits

Validation failures throw InvalidOperationException (message: Validation failed: ...).

Notes

• Dimension validation uses SixLabors.ImageSharp. Its license is enforced at build time and only applies to projects that reference ImageSharp directly (i.e. this library). Consuming services reference the compiled package transitively and need no license file.
• Only this library talks to storage; consumers depend on the IStorageProvider abstraction, so swapping providers requires no consumer code changes.