Table of Contents

Orleans.Lattice.Caching.AzureBlob configuration

The package has a single public options type, LatticeAzureBlobCacheOptions, bound through AddAzureBlobDistributedCache(configure).

LatticeAzureBlobCacheOptions

Property Type Default Meaning
ConnectionString string? null Storage-account connection string. When set, the cache builds the service client from it.
ServiceUri Uri? null Storage-account blob-service endpoint URI (for example https://{account}.blob.core.windows.net). When set, one of TokenCredential or SharedKeyCredential must also be supplied.
TokenCredential Azure.Core.TokenCredential? null Azure AD credential used with ServiceUri. Pair with new DefaultAzureCredential() for managed-identity scenarios. Mutually exclusive with SharedKeyCredential.
SharedKeyCredential Azure.Storage.StorageSharedKeyCredential? null Shared-key credential used with ServiceUri. Mutually exclusive with TokenCredential.
ServiceClient Azure.Storage.Blobs.BlobServiceClient? null A pre-built service client used verbatim. When set, ConfigureClientOptions is ignored and the host owns the client's lifetime and options. Mutually exclusive with the connection-string and service-URI modes.
ContainerName string DefaultContainerName (orleans-lattice-cache) The blob container that backs the cache. Created on first use (idempotent). Specify a non-default name to share an account across multiple caches without collisions.
KeyPrefix string "" (empty) Optional virtual-directory prefix prepended to every entry's blob name (for example tokens/). Lets several logical caches share one container. Empty stores entries at the container root. The prefix is prepended verbatim - no separator is inserted - so end it with / to place entries in a virtual directory.
ConfigureClientOptions Action<Azure.Storage.Blobs.BlobClientOptions>? null Optional callback invoked when the cache builds the client options, to attach custom retry policies, diagnostics, or transport. Ignored when ServiceClient is supplied.

Constant

const string DefaultContainerName = "orleans-lattice-cache" - the default ContainerName. It is lowercase alphanumeric with hyphens and within the three-to-sixty-three-character range Azure Blob Storage requires of a container name.

Authentication-mode rules

Exactly one authentication mode must be configured. The options are validated when the cache is first resolved; a violation throws InvalidOperationException with an actionable message:

  • Exactly one of ConnectionString, ServiceUri, or ServiceClient must be set. Zero modes, or more than one, is rejected.
  • When ServiceUri is set, exactly one of TokenCredential or SharedKeyCredential must accompany it.
  • A credential (TokenCredential or SharedKeyCredential) without ServiceUri is rejected.
  • ContainerName must not be null or whitespace.

The authentication mode is read once at construction; subsequent edits to these fields are not observed by the already-built container client.

Distributed token cache example

Point Microsoft.Identity.Web's distributed token cache at this backend by registering both on the same host. Any IDistributedCache consumer resolves the blob store.

using Microsoft.Extensions.DependencyInjection;
using Orleans.Lattice.Caching.AzureBlob;

public static class TokenCacheRegistration
{
    public static void Configure(IServiceCollection services) =>
        services.AddAzureBlobDistributedCache(options =>
        {
            options.ConnectionString = "UseDevelopmentStorage=true";
        });
}