> ## Documentation Index
> Fetch the complete documentation index at: https://pulse.mintlify.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Azure Blob Storage

> This health check verifies the ability to communicate with [Azure Blob Storage](https://azure.microsoft.com/en-us/products/storage/blobs/). It uses the provided [BlobServiceClient](https://learn.microsoft.com/dotnet/api/azure.storage.blobs.blobserviceclient) to get first or configured blob container.

## Installation

<Tabs>
  <Tab title=".NET CLI">
    ```bash theme={null}
    dotnet add package AspNetCore.Pulse.Azure.Storage.Blobs --version 8.0.4
    ```
  </Tab>

  <Tab title="Package Reference">
    ```xml theme={null}
    <PackageReference Include="AspNetCore.Pulse.Azure.Storage.Blobs" Version="8.0.4" />
    ```
  </Tab>

  <Tab title="Nuget">
    <a href="https://www.nuget.org/packages/AspNetCore.Pulse.Azure.Storage.Blobs/" target="_blank">Go to nuget page</a>
  </Tab>
</Tabs>

### Defaults

By default, the `BlobServiceClient` instance is resolved from service provider. `AzureBlobStorageHealthCheckOptions` does not provide any specific container name, so the health check fetches just first container.

```csharp theme={null}
void Configure(IHealthChecksBuilder builder)
{
    builder.Services.AddSingleton(sp => new BlobServiceClient(new Uri("azure-blob-storage-uri"), new DefaultAzureCredential()));
    builder.AddHealthChecks().AddAzureBlobStorage();
}
```

### Customization

You can additionally add the following parameters:

* `clientFactory`: A factory method to provide `BlobServiceClient` instance.
* `optionsFactory`: A factory method to provide `AzureBlobStorageHealthCheckOptions` instance. It allows to specify the container name.
* `name`: The health check name. The default is `azure_blob_storage`.
* `failureStatus`: The `HealthStatus` that should be reported when the health check fails. Default is `HealthStatus.Unhealthy`.
* `tags`: A list of tags that can be used to filter sets of health checks.
* `timeout`: A `System.TimeSpan` representing the timeout of the check.

```csharp theme={null}
void Configure(IHealthChecksBuilder builder)
{
    builder.Services.AddSingleton(sp => new BlobServiceClient(new Uri("azure-blob-storage-uri"), new DefaultAzureCredential()));
    builder.AddHealthChecks().AddAzureBlobStorage(
        optionsFactory: sp => new AzureBlobStorageHealthCheckOptions()
        {
            ContainerName = "demo"
        });
}
```

### Breaking changes

In the prior releases, `AzureBlobStorageHealthCheck` was a part of `Pulse.AzureStorage` package. It had a dependency on not just `Azure.Storage.Blobs`, but also `Azure.Storage.Queues` and `Azure.Storage.Files.Shares`. The packages have been split to avoid bringing unnecessary dependencies. Moreover, `AzureBlobStorageHealthCheck` was letting the users specify how `BlobServiceClient` should be created (from raw connection string or from endpoint uri and managed identity credentials), at a cost of maintaining an internal, static client instances cache. Now the type does not create client instances nor maintain an internal cache and **it's the caller responsibility to provide the instance of `BlobServiceClient`** (please see [#2040](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/issues/2040) for more details). Since Azure SDK recommends treating clients as singletons <see href="https://devblogs.microsoft.com/azure-sdk/lifetime-management-and-thread-safety-guarantees-of-azure-sdk-net-clients/" /> and client instances can be expensive to create, it's recommended to register a singleton factory method for Azure SDK clients. So the clients are created only when needed and once per whole application lifetime.