fixes #3085 Simple example for configuring the container apps environment (#3119)

* fixes #3085 Simple example for configuring the container apps environment with 'ConfigureInfrastructure'

* fixes #3085 Simple example for configuring the container apps environment with 'ConfigureInfrastructure'

* Apply suggestions from code review

---------

Co-authored-by: David Pine <david.pine@microsoft.com>

Author: mip1983

docs/azure/configure-aca-environments.md

@@ -64,6 +64,32 @@ builder.Build().Run();
 
 Calling this API ensures your existing Azure resources remain consistent and prevents duplication.
 
+## Customize provisioning infrastructure
+
+All .NET Aspire Azure resources are subclasses of the <xref:Aspire.Hosting.Azure.AzureProvisioningResource> type. This enables customization of the generated Bicep by providing a fluent API to configure the Azure resources—using the <xref:Aspire.Hosting.AzureProvisioningResourceExtensions.ConfigureInfrastructure``1(Aspire.Hosting.ApplicationModel.IResourceBuilder{``0},System.Action{Aspire.Hosting.Azure.AzureResourceInfrastructure})> API:
+
+```csharp
+var builder = DistributionApplicationBuilder.Create(args);
+
+var acaEnv = builder.AddAzureContainerAppEnvironment(Config.ContainEnvironmentName);
+
+acaEnv.ConfigureInfrastructure(config =>
+{
+    var resources = config.GetProvisionableResources();
+    var containerEnvironment = resources.OfType<ContainerAppManagedEnvironment>().FirstOrDefault();
+
+    containerEnvironment.Tags.Add("ExampleKey", "Example value");
+});
+```
+
+The preceding code:
+
+- Chains a call to the <xref:Aspire.Hosting.AzureProvisioningResourceExtensions.ConfigureInfrastructure*> API:
+  - The `infra` parameter is an instance of the <xref:Aspire.Hosting.Azure.AzureResourceInfrastructure> type.
+  - The provisionable resources are retrieved by calling the <xref:Azure.Provisioning.Infrastructure.GetProvisionableResources> method.
+  - The single <xref:Azure.Provisioning.AppContainers.ContainerAppManagedEnvironment> resource is retrieved.
+  - A tag is added to the Azure Container Apps environment resource with a key of `ExampleKey` and a value of `Example value`.
+
 ## See also
 
 - [.NET Aspire Azure integrations overview](integrations-overview.md)