Deprecating various known parameters in AzureBicepResource

Known parameter injection in AzureBicepResource has been deprecated. The parameters AzureBicepResource.KnownParameters.KeyVaultName, AzureBicepResource.KnownParameters.LogAnalyticsWorkspaceId, containerAppEnvironmentId, and containerAppEnvironmentName are now marked as [Obsolete] and ignored during infrastructure generation. Developers must explicitly model these resources or use new helper APIs to ensure proper configuration.

Version introduced

This change applies to Aspire starting from version 7.4.2025.

Previous behavior

Previously, Aspire automatically injected the following known parameters into Bicep templates at build time without requiring explicit assignment:

For example:

// keyvault.bicep
param keyVaultName string
resource kv 'Microsoft.KeyVault/vaults@2023-07-01' = {
  name: keyVaultName
  ...
}

builder.AddBicepTemplateFile("kv", "keyvault.bicep"); // No parameter assignment needed
builder.AddContainer("api", "image");

Aspire resolved these parameters automatically, allowing templates to deploy without explicit wiring.

New behavior

Aspire no longer pre-populates the deprecated parameters. If a Bicep template declares any of these parameters without explicit assignment, deployment fails with an "undefined parameter" error. Developers must now explicitly model resources and pass their values to templates.

For example:

var env = builder.AddAzureContainerAppEnvironment("env");
var kv  = builder.AddAzureKeyVault("kv");
var la  = builder.AddAzureLogAnalyticsWorkspace("la");

builder.AddBicepTemplateFile("kvTemplate", "keyvault.bicep")
       .WithParameter("keyVaultName", kv.NameOutputReference);

builder.AddBicepTemplateFile("apiTemplate", "api.bicep")
       .WithParameter("containerAppEnvironmentName", env.NameOutputReference);

Inside the Bicep template:

param containerAppEnvironmentName string

resource env 'Microsoft.App/managedEnvironments@2024-03-01' existing = {
  name: containerAppEnvironmentName
}

var environmentId = env.id

Type of breaking change

This is both a source incompatible and behavioral change.

Reason for change

Aspire now supports modeling multiple compute environments in a single application graph. Automatically injecting global parameters created ambiguity, hid dependencies, and complicated debugging. This change enforces explicit wiring, ensuring predictable behavior and enabling future scenarios where resources target specific environments.

Recommended action

1. Stop using obsolete constants

   Remove any code that relies on AzureBicepResource.KnownParameters.KeyVaultName, AzureBicepResource.KnownParameters.LogAnalyticsWorkspaceId, containerAppEnvironmentId, or containerAppEnvironmentName.

2. Model resources explicitly

   Define resources like Key Vaults, Log Analytics Workspaces, and Container App Environments explicitly in your code.

   var env = builder.AddAzureContainerAppEnvironment("env");
   var kv = builder.AddAzureKeyVault("kv");
   var la = builder.AddAzureLogAnalyticsWorkspace("la");
   

3. Pass parameters explicitly

   Use strongly-typed properties like NameOutputReference to pass resource values to templates.

   builder.AddBicepTemplateFile("template", "file.bicep")
          .WithParameter("keyVaultName", kv.NameOutputReference);
   

4. Address warnings

   Update code to resolve [Obsolete] warnings by replacing deprecated constants with explicit resource definitions.

Affected APIs

• AzureBicepResource.KnownParameters.KeyVaultName: Obsolete.
• AzureBicepResource.KnownParameters.LogAnalyticsWorkspaceId: Obsolete.