Soenneker.Blob.Client 4.0.2183

Soenneker.Blob.Client

Resolves Azure BlobClient instances through a cached container client and creates a missing container before returning the blob client.

Install

dotnet add package Soenneker.Blob.Client

Configure the Azure Storage connection string:

{
  "Azure": {
    "Storage": {
      "Blob": {
        "ConnectionString": "<connection string>"
      }
    }
  }
}

Keep the real value in an environment-specific secret provider rather than committing it to configuration files.

Register the utility in Program.cs:

using Soenneker.Blob.Client.Registrars;

builder.Services.AddBlobClientUtilAsSingleton();

The singleton registration is the usual choice. A scoped registration is available, but it still uses the singleton container cache.

Resolve a blob client

using Azure.Storage.Blobs;
using Soenneker.Blob.Client.Abstract;

public sealed class InvoiceStore(IBlobClientUtil blobClients)
{
    public async ValueTask<BlobClient> GetInvoice(
        Guid invoiceId,
        CancellationToken cancellationToken)
    {
        return await blobClients.Get(
            "invoices",
            $"2026/{invoiceId:N}.pdf",
            cancellationToken: cancellationToken);
    }
}

relativeUrl is an Azure blob name, not a URL. Slashes create a virtual hierarchy in tools and listings, but the name remains one blob key.

The returned BlobClient can be used with the Azure SDK directly:

BlobClient blob = await blobClients.Get(
    "invoices",
    "2026/summary.pdf",
    cancellationToken: cancellationToken);

await blob.UploadAsync(stream, overwrite: true, cancellationToken);

Container behavior

• Container names are converted to lowercase before lookup.
• The first lookup for a container checks Azure and creates it if missing.
• PublicAccessType.None is the default and keeps a newly created container private.
• publicAccessType is used only when creating a missing container. It does not inspect or change the access policy of an existing container.
• Container clients are cached by normalized container name. Use one consistent public-access choice for each container.

Operational notes

• Cancellation stops pending work; it does not undo work that has already completed.
• Resolving a blob client can perform a container existence check or creation, so it is not a purely local factory call.
• This utility does not upload, download, overwrite, delete, or authorize individual blobs; those behaviors come from the returned Azure SDK client and its credentials.
• Treat public container access as an explicit data-exposure decision. Prefer private containers and SAS URLs for limited external access.