addressed feedback

bundle/apps/validate.go

@@ -0,0 +1,41 @@
+package apps
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/databricks/cli/bundle"
+	"github.com/databricks/cli/libs/diag"
+)
+
+type validate struct {
+}
+
+func (v *validate) Apply(ctx context.Context, b *bundle.Bundle) diag.Diagnostics {
+	var diags diag.Diagnostics
+	for _, app := range b.Config.Resources.Apps {
+		possibleConfigFiles := []string{"app.yml", "app.yaml"}
+		for _, configFile := range possibleConfigFiles {
+			cf := filepath.Join(b.SyncRootPath, app.SourceCodePath, configFile)
+			if _, err := os.Stat(cf); err == nil {
+				diags = append(diags, diag.Diagnostic{
+					Severity: diag.Error,
+					Summary:  "app.yml detected",
+					Detail:   fmt.Sprintf("remove %s and use 'config' property for app resource '%s' instead", cf, app.Name),
+				})
+			}
+		}
+	}
+
+	return diags
+}
+
+func (v *validate) Name() string {
+	return "apps.Validate"
+}
+
+func Validate() bundle.Mutator {
+	return &validate{}
+}

bundle/apps/validate_test.go

@@ -0,0 +1,55 @@
+package apps
+
+import (
+	"context"
+	"path/filepath"
+	"testing"
+
+	"github.com/databricks/cli/bundle"
+	"github.com/databricks/cli/bundle/config"
+	"github.com/databricks/cli/bundle/config/mutator"
+	"github.com/databricks/cli/bundle/config/resources"
+	"github.com/databricks/cli/bundle/internal/bundletest"
+	"github.com/databricks/cli/internal/testutil"
+	"github.com/databricks/cli/libs/dyn"
+	"github.com/databricks/cli/libs/vfs"
+	"github.com/databricks/databricks-sdk-go/service/apps"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAppsValidate(t *testing.T) {
+	tmpDir := t.TempDir()
+	testutil.Touch(t, tmpDir, "app1", "app.yml")
+	testutil.Touch(t, tmpDir, "app2", "app.py")
+
+	b := &bundle.Bundle{
+		BundleRootPath: tmpDir,
+		SyncRootPath:   tmpDir,
+		SyncRoot:       vfs.MustNew(tmpDir),
+		Config: config.Root{
+			Resources: config.Resources{
+				Apps: map[string]*resources.App{
+					"app1": {
+						App: &apps.App{
+							Name: "app1",
+						},
+						SourceCodePath: "./app1",
+					},
+					"app2": {
+						App: &apps.App{
+							Name: "app2",
+						},
+						SourceCodePath: "./app2",
+					},
+				},
+			},
+		},
+	}
+
+	bundletest.SetLocation(b, ".", []dyn.Location{{File: filepath.Join(tmpDir, "databricks.yml")}})
+
+	diags := bundle.Apply(context.Background(), b, bundle.Seq(mutator.TranslatePaths(), Validate()))
+	require.Len(t, diags, 1)
+	require.Equal(t, "app.yml detected", diags[0].Summary)
+	require.Contains(t, diags[0].Detail, "app.yml and use 'config' property for app resource")
+}

bundle/config/mutator/apply_presets.go

@@ -222,18 +222,7 @@ func (m *applyPresets) Apply(ctx context.Context, b *bundle.Bundle) diag.Diagnos
 		dashboard.DisplayName = prefix + dashboard.DisplayName
 	}
 
-	// Apps: Prefix
-	for key, app := range r.Apps {
-		if app == nil || app.App == nil {
-			diags = diags.Extend(diag.Errorf("app %s is not defined", key))
-			continue
-		}
-
-		app.Name = textutil.NormalizeString(prefix + app.Name)
-		// Normalize the app name to ensure it is a valid identifier.
-		// App supports only alphanumeric characters and hyphens.
-		app.Name = strings.ReplaceAll(app.Name, "_", "-")
-	}
+	// Apps: No presets
 
 	if config.IsExplicitlyEnabled((b.Config.Presets.SourceLinkedDeployment)) {
 		isDatabricksWorkspace := dbr.RunsOnRuntime(ctx) && strings.HasPrefix(b.SyncRootPath, "/Workspace/")

bundle/config/mutator/apply_presets_test.go

@@ -12,7 +12,6 @@ import (
 	"github.com/databricks/cli/bundle/internal/bundletest"
 	"github.com/databricks/cli/libs/dbr"
 	"github.com/databricks/cli/libs/dyn"
-	"github.com/databricks/databricks-sdk-go/service/apps"
 	"github.com/databricks/databricks-sdk-go/service/catalog"
 	"github.com/databricks/databricks-sdk-go/service/jobs"
 	"github.com/stretchr/testify/require"
@@ -483,59 +482,3 @@ func TestApplyPresetsSourceLinkedDeployment(t *testing.T) {
 		})
 	}
 }
-
-func TestApplyPresetsPrefixForApps(t *testing.T) {
-	tests := []struct {
-		name   string
-		prefix string
-		app    *resources.App
-		want   string
-	}{
-		{
-			name:   "add prefix to app",
-			prefix: "[prefix] ",
-			app: &resources.App{
-				App: &apps.App{
-					Name: "app1",
-				},
-			},
-			want: "prefix-app1",
-		},
-		{
-			name:   "add empty prefix to app",
-			prefix: "",
-			app: &resources.App{
-				App: &apps.App{
-					Name: "app1",
-				},
-			},
-			want: "app1",
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			b := &bundle.Bundle{
-				Config: config.Root{
-					Resources: config.Resources{
-						Apps: map[string]*resources.App{
-							"app1": tt.app,
-						},
-					},
-					Presets: config.Presets{
-						NamePrefix: tt.prefix,
-					},
-				},
-			}
-
-			ctx := context.Background()
-			diag := bundle.Apply(ctx, b, mutator.ApplyPresets())
-
-			if diag.HasError() {
-				t.Fatalf("unexpected error: %v", diag)
-			}
-
-			require.Equal(t, tt.want, b.Config.Resources.Apps["app1"].Name)
-		})
-	}
-}

bundle/config/mutator/merge_apps.go

@@ -37,7 +37,7 @@ func (m *mergeApps) Apply(ctx context.Context, b *bundle.Bundle) diag.Diagnostic
 		}
 
 		return dyn.Map(v, "resources.apps", dyn.Foreach(func(_ dyn.Path, app dyn.Value) (dyn.Value, error) {
-			return dyn.Map(app, "resources", merge.ElementsByKey("name", m.resourceName))
+			return dyn.Map(app, "resources", merge.ElementsByKeyWithOverride("name", m.resourceName))
 		}))
 	})
 

bundle/config/mutator/merge_apps_test.go

@@ -42,6 +42,13 @@ func TestMergeApps(t *testing.T) {
 										Permission: "CAN_MANAGE",
 									},
 								},
+								{
+									Name: "sql1",
+									Job: &apps.AppResourceJob{
+										Id:         "9876",
+										Permission: "CAN_MANAGE",
+									},
+								},
 							},
 						},
 					},
@@ -60,5 +67,7 @@ func TestMergeApps(t *testing.T) {
 	assert.Equal(t, "sql1", j.Resources[1].Name)
 
 	assert.Equal(t, "CAN_MANAGE", string(j.Resources[0].Job.Permission))
-	assert.Equal(t, "CAN_USE", string(j.Resources[1].SqlWarehouse.Permission))
+
+	assert.Nil(t, j.Resources[1].SqlWarehouse)
+	assert.Equal(t, "CAN_MANAGE", string(j.Resources[1].Job.Permission))
 }

bundle/config/mutator/process_target_mode_test.go

@@ -426,6 +426,12 @@ func TestAllNonUcResourcesAreRenamed(t *testing.T) {
 			for _, key := range field.MapKeys() {
 				resource := field.MapIndex(key)
 				nameField := resource.Elem().FieldByName("Name")
+
+				// Skip apps, as they are not renamed
+				if resourceType == "Apps" {
+					continue
+				}
+
 				if !nameField.IsValid() || nameField.Kind() != reflect.String {
 					continue
 				}

bundle/config/mutator/run_as.go

@@ -119,6 +119,16 @@ func validateRunAs(b *bundle.Bundle) diag.Diagnostics {
 		))
 	}
 
+	// Apps do not support run_as in the API.
+	if len(b.Config.Resources.Apps) > 0 {
+		diags = diags.Extend(reportRunAsNotSupported(
+			"apps",
+			b.Config.GetLocation("resources.apps"),
+			b.Config.Workspace.CurrentUser.UserName,
+			identity,
+		))
+	}
+
 	return diags
 }
 

bundle/config/resources/apps.go

@@ -14,6 +14,7 @@ import (
 type App struct {
 	// This represents the id which is the name of the app that can be used
 	// as a reference in other resources. This value is returned by terraform.
+	// This equals to app name and added for symmetry with other resources.
 	ID string `json:"id,omitempty" bundle:"readonly"`
 
 	// SourceCodePath is a required field used by DABs to point databricks app source code
@@ -23,7 +24,7 @@ type App struct {
 	// Config is an optional field which allows configuring the app following Databricks app configuration format like in app.yml.
 	// When this field is set, DABs read the configuration set in this field and write
 	// it to app.yml in the root of the source code folder in Databricks workspace.
-	// If there’s app.yml defined already, it will be overridden.
+	// If there’s app.yml defined locally, DABs will raise an error.
 	Config map[string]interface{} `json:"config,omitempty"`
 
 	Permissions    []Permission   `json:"permissions,omitempty"`

bundle/phases/initialize.go

@@ -2,6 +2,7 @@ package phases
 
 import (
 	"github.com/databricks/cli/bundle"
+	"github.com/databricks/cli/bundle/apps"
 	"github.com/databricks/cli/bundle/config"
 	"github.com/databricks/cli/bundle/config/mutator"
 	pythonmutator "github.com/databricks/cli/bundle/config/mutator/python"
@@ -82,6 +83,8 @@ func Initialize() bundle.Mutator {
 			mutator.TranslatePaths(),
 			trampoline.WrapperWarning(),
 
+			apps.Validate(),
+
 			permissions.ValidateSharedRootPermissions(),
 			permissions.ApplyBundlePermissions(),
 			permissions.FilterCurrentUser(),

libs/dyn/merge/elements_by_key.go

@@ -7,7 +7,7 @@ type elementsByKey struct {
 	keyFunc func(dyn.Value) string
 }
 
-func (e elementsByKey) Map(_ dyn.Path, v dyn.Value) (dyn.Value, error) {
+func (e elementsByKey) doMap(_ dyn.Path, v dyn.Value, mergeFunc func(a dyn.Value, b dyn.Value) (dyn.Value, error)) (dyn.Value, error) {
 	// We know the type of this value is a sequence.
 	// For additional defence, return self if it is not.
 	elements, ok := v.AsSequence()
@@ -33,7 +33,7 @@ func (e elementsByKey) Map(_ dyn.Path, v dyn.Value) (dyn.Value, error) {
 		}
 
 		// Merge this instance into the reference.
-		nv, err := Merge(ref, elements[i])
+		nv, err := mergeFunc(ref, elements[i])
 		if err != nil {
 			return v, err
 		}
@@ -55,6 +55,26 @@ func (e elementsByKey) Map(_ dyn.Path, v dyn.Value) (dyn.Value, error) {
 	return dyn.NewValue(out, v.Locations()), nil
 }
 
+func (e elementsByKey) Map(_ dyn.Path, v dyn.Value) (dyn.Value, error) {
+	return e.doMap(nil, v, Merge)
+}
+
+func (e elementsByKey) MapWithOverride(p dyn.Path, v dyn.Value) (dyn.Value, error) {
+	return e.doMap(nil, v, func(a dyn.Value, b dyn.Value) (dyn.Value, error) {
+		return Override(a, b, OverrideVisitor{
+			VisitInsert: func(_ dyn.Path, v dyn.Value) (dyn.Value, error) {
+				return v, nil
+			},
+			VisitDelete: func(valuePath dyn.Path, left dyn.Value) error {
+				return nil
+			},
+			VisitUpdate: func(_ dyn.Path, a dyn.Value, b dyn.Value) (dyn.Value, error) {
+				return b, nil
+			},
+		})
+	})
+}
+
 // ElementsByKey returns a [dyn.MapFunc] that operates on a sequence
 // where each element is a map. It groups elements by a key and merges
 // elements with the same key.
@@ -65,3 +85,7 @@ func (e elementsByKey) Map(_ dyn.Path, v dyn.Value) (dyn.Value, error) {
 func ElementsByKey(key string, keyFunc func(dyn.Value) string) dyn.MapFunc {
 	return elementsByKey{key, keyFunc}.Map
 }
+
+func ElementsByKeyWithOverride(key string, keyFunc func(dyn.Value) string) dyn.MapFunc {
+	return elementsByKey{key, keyFunc}.MapWithOverride
+}