Automatically Invalidate Azure Key Vault Secrets
The Arcus.BackgroundJobs.KeyVault
library provides a background job to automatically invalidate cached Azure Key Vault secrets from an ICachedSecretProvider
instance of your choice.
How does it work?
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This automation works by subscribing on the SecretNewVersionCreated
event of an Azure Key Vault resource and placing those events on a Azure Service Bus Topic; which we process in our background job.
To make this automation operational, following Azure Resources has to be used:
- Azure Key Vault instance
- Azure Service Bus Topic
- Azure Event Grid subscription for
SecretNewVersionCreated
events that are sent to the Azure Service Bus Topic
Usage
Our background job has to be configured in ConfigureServices
method:
using Arcus.Security.Core;
using Arcus.Security.Core.Caching;
using Microsoft.Extensions.DependencyInjection;
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
// An 'ISecretProvider' implementation (see: https://security.arcus-azure.net/) to access the Azure Service Bus Topic resource;
// this will get the 'serviceBusTopicConnectionStringSecretKey' string (configured below) and has to retrieve the connection string for the topic.
services.AddSingleton<ISecretProvider>(serviceProvider => ...);
// An `ICachedSecretProvider` implementation which secret keys will automatically be invalidated.
services.AddSingleton<ICachedSecretProvider>(serviceProvider => new CachedSecretProvider(mySecretProvider));
services.AddAutoInvalidateKeyVaultSecretBackgroundJob(
// Prefix of the Azure Service Bus Topic subscription;
// this allows the background jobs to support applications that are running multiple instances, processing the same type of events, without conflicting subscription names.
subscriptionNamePrefix: "MyPrefix"
// Connection string secret key to a Azure Service Bus Topic.
serviceBusTopicConnectionStringSecretKey: "MySecretKeyToServiceBusTopicConnectionString");
}
}