Remove infrastructure outputs from .env on azd down

cli/azd/cmd/down.go

@@ -114,21 +114,10 @@ func (a *downAction) Run(ctx context.Context) (*actions.ActionResult, error) {
 	startTime := time.Now()
 
 	destroyOptions := provisioning.NewDestroyOptions(a.flags.forceDelete, a.flags.purgeDelete)
-	destroyResult, err := infraManager.Destroy(ctx, destroyOptions)
-	if err != nil {
+	if _, err = infraManager.Destroy(ctx, destroyOptions); err != nil {
 		return nil, fmt.Errorf("deleting infrastructure: %w", err)
 	}
 
-	// Remove any outputs from the template from the environment since destroying the infrastructure
-	// invalidated them all.
-	for outputName := range destroyResult.Outputs {
-		a.env.DotenvDelete(outputName)
-	}
-
-	if err := a.env.Save(); err != nil {
-		return nil, fmt.Errorf("saving environment: %w", err)
-	}
-
 	return &actions.ActionResult{
 		Message: &actions.ResultMessage{
 			Header: fmt.Sprintf("Your application was removed from Azure in %s.", ux.DurationAsText(time.Since(startTime))),

cli/azd/pkg/environment/environment.go

@@ -51,6 +51,10 @@ type Environment struct {
 	// dotenv is a map of keys to values, persisted to the `.env` file stored in this environment's [Root].
 	dotenv map[string]string
 
+	// deletedKeys keeps track of deleted keys from the `.env` to be reapplied before a merge operation
+	// happens in Save
+	deletedKeys map[string]struct{}
+
 	// Config is environment specific config
 	Config config.Config
 
@@ -123,17 +127,19 @@ func GetEnvironment(azdContext *azdcontext.AzdContext, name string) (*Environmen
 // to a given directory when saved.
 func EmptyWithRoot(root string) *Environment {
 	return &Environment{
-		Root:   root,
-		dotenv: make(map[string]string),
-		Config: config.NewEmptyConfig(),
+		Root:        root,
+		dotenv:      make(map[string]string),
+		deletedKeys: make(map[string]struct{}),
+		Config:      config.NewEmptyConfig(),
 	}
 }
 
 // Ephemeral returns returns an empty ephemeral environment (i.e. not backed by a file) with a set
 func Ephemeral() *Environment {
 	return &Environment{
-		dotenv: make(map[string]string),
-		Config: config.NewEmptyConfig(),
+		dotenv:      make(map[string]string),
+		deletedKeys: make(map[string]struct{}),
+		Config:      config.NewEmptyConfig(),
 	}
 }
 
@@ -177,6 +183,7 @@ func (e *Environment) LookupEnv(key string) (string, bool) {
 // does not exist. [Save] should be called to ensure this change is persisted.
 func (e *Environment) DotenvDelete(key string) {
 	delete(e.dotenv, key)
+	e.deletedKeys[key] = struct{}{}
 }
 
 // Dotenv returns a copy of the key value pairs from the .env file in the environment.
@@ -188,6 +195,7 @@ func (e *Environment) Dotenv() map[string]string {
 // called to ensure this change is persisted.
 func (e *Environment) DotenvSet(key string, value string) {
 	e.dotenv[key] = value
+	delete(e.deletedKeys, key)
 }
 
 // Reloads environment variables and configuration
@@ -196,10 +204,12 @@ func (e *Environment) Reload() error {
 	envPath := filepath.Join(e.Root, azdcontext.DotEnvFileName)
 	if envMap, err := godotenv.Read(envPath); errors.Is(err, os.ErrNotExist) {
 		e.dotenv = make(map[string]string)
+		e.deletedKeys = make(map[string]struct{})
 	} else if err != nil {
 		return fmt.Errorf("loading .env: %w", err)
 	} else {
 		e.dotenv = envMap
+		e.deletedKeys = make(map[string]struct{})
 	}
 
 	// Reload env config
@@ -239,6 +249,7 @@ func (e *Environment) Save() error {
 
 	// Cache current values & reload to get any new env vars
 	currentValues := e.dotenv
+	deletedValues := e.deletedKeys
 	if err := e.Reload(); err != nil {
 		return fmt.Errorf("failed reloading env vars, %w", err)
 	}
@@ -248,6 +259,11 @@ func (e *Environment) Save() error {
 		e.dotenv[key] = value
 	}
 
+	// Replay deletion
+	for key := range deletedValues {
+		delete(e.dotenv, key)
+	}
+
 	err := os.MkdirAll(e.Root, osutil.PermissionDirectory)
 	if err != nil {
 		return fmt.Errorf("failed to create a directory: %w", err)
@@ -269,7 +285,7 @@ func (e *Environment) GetEnvName() string {
 
 // SetEnvName is shorthand for DotenvSet(EnvNameEnvVarName, envname)
 func (e *Environment) SetEnvName(envname string) {
-	e.dotenv[EnvNameEnvVarName] = envname
+	e.DotenvSet(EnvNameEnvVarName, envname)
 }
 
 // GetSubscriptionId is shorthand for Getenv(SubscriptionIdEnvVarName)
@@ -284,7 +300,7 @@ func (e *Environment) GetTenantId() string {
 
 // SetLocation is shorthand for DotenvSet(SubscriptionIdEnvVarName, location)
 func (e *Environment) SetSubscriptionId(id string) {
-	e.dotenv[SubscriptionIdEnvVarName] = id
+	e.DotenvSet(SubscriptionIdEnvVarName, id)
 }
 
 // GetLocation is shorthand for Getenv(LocationEnvVarName)
@@ -294,7 +310,7 @@ func (e *Environment) GetLocation() string {
 
 // SetLocation is shorthand for DotenvSet(LocationEnvVarName, location)
 func (e *Environment) SetLocation(location string) {
-	e.dotenv[LocationEnvVarName] = location
+	e.DotenvSet(LocationEnvVarName, location)
 }
 
 func normalize(key string) string {
@@ -308,7 +324,7 @@ func (e *Environment) GetServiceProperty(serviceName string, propertyName string
 
 // Sets the value of a service-namespaced property in the environment.
 func (e *Environment) SetServiceProperty(serviceName string, propertyName string, value string) {
-	e.dotenv[fmt.Sprintf("SERVICE_%s_%s", normalize(serviceName), propertyName)] = value
+	e.DotenvSet(fmt.Sprintf("SERVICE_%s_%s", normalize(serviceName), propertyName), value)
 }
 
 // Creates a slice of key value pairs, based on the entries in the `.env` file like `KEY=VALUE` that

cli/azd/pkg/environment/environment_test.go

@@ -148,6 +148,28 @@ func Test_SaveAndReload(t *testing.T) {
 	require.Equal(t, env.dotenv["SERVICE_API_ENDPOINT_URL"], "http://api.example.com")
 	require.Equal(t, "SUBSCRIPTION_ID", env.GetSubscriptionId())
 	require.Equal(t, "eastus2", env.GetLocation())
+
+	// Delete the newly added property
+	env.DotenvDelete("SERVICE_WEB_ENDPOINT_URL")
+	err = env.Save()
+	require.NoError(t, err)
+
+	// Verify the property is deleted
+	_, ok := env.LookupEnv("SERVICE_WEB_ENDPOINT_URL")
+	require.False(t, ok)
+
+	// Delete an existing key, then add it with a different value and save the environment, to ensure we
+	// don't drop the existing key even though it was deleted in an earlier operation.
+	env.DotenvDelete("SERVICE_API_ENDPOINT_URL")
+	env.DotenvSet("SERVICE_API_ENDPOINT_URL", "http://api.example.com/updated")
+
+	err = env.Save()
+	require.NoError(t, err)
+
+	// Verify the property still exists, and has the updated value.
+	value, ok := env.LookupEnv("SERVICE_API_ENDPOINT_URL")
+	require.True(t, ok)
+	require.Equal(t, "http://api.example.com/updated", value)
 }
 
 func TestCleanName(t *testing.T) {

cli/azd/test/functional/up_test.go

@@ -260,6 +260,14 @@ func Test_CLI_Up_Down_ContainerApp(t *testing.T) {
 
 	_, err = cli.RunCommand(ctx, "infra", "delete", "--force", "--purge")
 	require.NoError(t, err)
+
+	// As part of deleting the infrastructure, outputs of the infrastructure such as "WEBSITE_URL" should
+	// have been removed from the environment.
+	env, err = godotenv.Read(filepath.Join(dir, azdcontext.EnvironmentDirectoryName, envName, ".env"))
+	require.NoError(t, err)
+
+	_, has = env["WEBSITE_URL"]
+	require.False(t, has, "WEBSITE_URL should have been removed from the environment as part of infrastructure removal")
 }
 
 func Test_CLI_Up_ResourceGroupScope(t *testing.T) {