azurerm_container_app: add identity field to registry block

Fixes #20412

internal/services/containerapps/container_app_resource.go

@@ -177,14 +177,19 @@ func (r ContainerAppResource) Create() sdk.ResourceFunc {
 				return fmt.Errorf("reading %s for %s: %+v", *envId, id, err)
 			}
 
+			registries, err := helpers.ExpandContainerAppRegistries(app.Registries)
+			if err != nil {
+				return fmt.Errorf("invalid registry config for %s: %+v", id, err)
+			}
+
 			containerApp := containerapps.ContainerApp{
 				Location: location.Normalize(env.Model.Location),
 				Properties: &containerapps.ContainerAppProperties{
 					Configuration: &containerapps.Configuration{
 						Ingress:    helpers.ExpandContainerAppIngress(app.Ingress, id.ContainerAppName),
 						Dapr:       helpers.ExpandContainerAppDapr(app.Dapr),
 						Secrets:    helpers.ExpandContainerSecrets(app.Secrets),
-						Registries: helpers.ExpandContainerAppRegistries(app.Registries),
+						Registries: registries,
 					},
 					ManagedEnvironmentId: pointer.To(app.ManagedEnvironmentId),
 					Template:             helpers.ExpandContainerAppTemplate(app.Template, metadata),

internal/services/containerapps/helpers/container_apps.go

@@ -18,6 +18,7 @@ type Registry struct {
 	PasswordSecretRef string `tfschema:"password_secret_name"`
 	Server            string `tfschema:"server"`
 	UserName          string `tfschema:"username"`
+	Identity          string `tfschema:"identity"`
 }
 
 func ContainerAppRegistrySchema() *pluginsdk.Schema {
@@ -35,38 +36,59 @@ func ContainerAppRegistrySchema() *pluginsdk.Schema {
 				},
 
 				"username": {
-					Type:         pluginsdk.TypeString,
-					Required:     true,
-					ValidateFunc: validation.StringIsNotEmpty,
-					Description:  "The username to use for this Container Registry.",
+					Type:        pluginsdk.TypeString,
+					Required:    false,
+					Description: "The username to use for this Container Registry.",
 				},
 
 				"password_secret_name": {
-					Type:         pluginsdk.TypeString,
-					Required:     true,
-					ValidateFunc: validation.StringIsNotEmpty,
-					Description:  "The name of the Secret Reference containing the password value for this user on the Container Registry.",
+					Type:        pluginsdk.TypeString,
+					Required:    false,
+					Description: "The name of the Secret Reference containing the password value for this user on the Container Registry.",
+				},
+
+				"identity": {
+					Type:        pluginsdk.TypeString,
+					Required:    false,
+					Description: "ID of the System or User Managed Identity used to pull images from the Container Registry",
 				},
 			},
 		},
 	}
 }
 
-func ExpandContainerAppRegistries(input []Registry) *[]containerapps.RegistryCredentials {
+func ValidateContainerAppRegistry(r Registry) error {
+	if r.Identity != "" && (r.UserName != "" || r.PasswordSecretRef != "") {
+		return fmt.Errorf("identity and username/password_secret_name are mutually exclusive")
+	}
+	if r.Identity == "" && r.UserName == "" && r.PasswordSecretRef == "" {
+		return fmt.Errorf("must supply either identity or username/password_secret_name")
+	}
+	if (r.UserName != "" && r.PasswordSecretRef == "") || (r.UserName == "" && r.PasswordSecretRef != "") {
+		return fmt.Errorf("must supply both username and password_secret_name")
+	}
+	return nil
+}
+
+func ExpandContainerAppRegistries(input []Registry) (*[]containerapps.RegistryCredentials, error) {
 	if input == nil {
-		return nil
+		return nil, nil
 	}
 
 	registries := make([]containerapps.RegistryCredentials, 0)
 	for _, v := range input {
+		if err := ValidateContainerAppRegistry(v); err != nil {
+			return nil, err
+		}
 		registries = append(registries, containerapps.RegistryCredentials{
 			Server:            pointer.To(v.Server),
 			Username:          pointer.To(v.UserName),
 			PasswordSecretRef: pointer.To(v.PasswordSecretRef),
+			Identity:          pointer.To(v.Identity),
 		})
 	}
 
-	return &registries
+	return &registries, nil
 }
 
 func FlattenContainerAppRegistries(input *[]containerapps.RegistryCredentials) []Registry {
@@ -80,6 +102,7 @@ func FlattenContainerAppRegistries(input *[]containerapps.RegistryCredentials) [
 			PasswordSecretRef: pointer.From(v.PasswordSecretRef),
 			Server:            pointer.From(v.Server),
 			UserName:          pointer.From(v.Username),
+			Identity:          pointer.From(v.Identity),
 		})
 	}
 

internal/services/containerapps/helpers/container_apps_test.go

@@ -0,0 +1,66 @@
+package helpers
+
+import (
+	"testing"
+)
+
+func TestValidateContainerAppRegistry(t *testing.T) {
+	cases := []struct {
+		Input Registry
+		Valid bool
+	}{
+		{
+			Input: Registry{
+				Server:            "registry.example.com",
+				UserName:          "user",
+				PasswordSecretRef: "secretref",
+			},
+			Valid: true,
+		},
+		{
+			Input: Registry{
+				Server:   "registry.example.com",
+				Identity: "identity",
+			},
+			Valid: true,
+		},
+		{
+			Input: Registry{
+				Server: "registry.example.com",
+			},
+			Valid: false,
+		},
+		{
+			Input: Registry{
+				Server:            "registry.example.com",
+				UserName:          "user",
+				PasswordSecretRef: "secretref",
+				Identity:          "identity",
+			},
+			Valid: false,
+		},
+		{
+			Input: Registry{
+				Server:            "registry.example.com",
+				PasswordSecretRef: "secretref",
+			},
+			Valid: false,
+		},
+		{
+			Input: Registry{
+				Server:   "registry.example.com",
+				UserName: "user",
+			},
+			Valid: false,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Logf("[DEBUG] Testing Value %s", tc.Input)
+		err := ValidateContainerAppRegistry(tc.Input)
+		valid := err == nil
+		if tc.Valid != valid {
+			t.Fatalf("Expected %t but got %t for %s", tc.Valid, valid, tc.Input)
+		}
+	}
+}

website/docs/r/container_app.html.markdown

@@ -315,11 +315,16 @@ A `dapr` block supports the following:
 
 A `registry` block supports the following:
 
-* `password_secret_name` - (Required) The name of the Secret Reference containing the password value for this user on the Container Registry.
-
 * `server` - (Required) The hostname for the Container Registry.
 
-* `username` - (Required) The username to use for this Container Registry.
+The authentication details must also be supplied, `identity` and `username`/`password_secret_name` are mutually exclusive.
+
+* `identity` - (Optional) Resource ID for the User Assigned Managed identity to use when pulling from the Container Registry.
+
+* `password_secret_name` - (Optional) The name of the Secret Reference containing the password value for this user on the Container Registry, `username` must also be supplied.
+
+* `username` - (Optional) The username to use for this Container Registry, `password_secret_name` must also be supplied..
+
 
 
 ## Attributes Reference