From 0f8d13738dbcc32eb74c537e62ff5c09507e9b33 Mon Sep 17 00:00:00 2001
From: Jakub Zych <jakub@keios.eu>
Date: Tue, 6 Oct 2026 15:37:00 +0200
Subject: [PATCH] feat(14.2.1-05): hydrate ML create/GET/save through
 TranslatedExact

Form schema meta lists enabled locales, Show/save expand mltext maps
without D-11 fallback, and the SPA seeds and adopt-merges every locale.

Co-authored-by: Cursor <cursoragent@cursor.com>
---
 .../components/form/fields/MLTextField.vue    |  8 +-
 admin/src/components/form/formContext.ts      |  3 +
 admin/src/components/form/formState.ts        | 33 +++++++-
 admin/src/views/FormView.vue                  | 20 +++--
 admin/tests/form/MLFields.test.ts             | 71 ++++++++++++----
 modules/cabana/crud.go                        |  8 +-
 modules/cabana/field_ml.go                    | 80 ++++++++++++++++++-
 modules/cabana/http.go                        | 29 +++++++
 modules/cabana/ml_smoke_test.go               | 28 ++++++-
 modules/cabana/ml_test.go                     | 58 +++++++++++++-
 modules/cabana/schema_types.go                |  5 +-
 11 files changed, 309 insertions(+), 34 deletions(-)

diff --git a/admin/src/components/form/fields/MLTextField.vue b/admin/src/components/form/fields/MLTextField.vue
index a514374..35293f8 100644
--- a/admin/src/components/form/fields/MLTextField.vue
+++ b/admin/src/components/form/fields/MLTextField.vue
@@ -1,16 +1,18 @@
 <script setup lang="ts">
-import { computed, onMounted, onUnmounted, ref } from 'vue'
+import { computed, inject, onMounted, onUnmounted, ref } from 'vue'
 import type { FieldControlProps } from '../control'
 import TextField from './TextField.vue'
+import { FORM_ENABLED_LOCALES } from '../formContext'
 import { ML_LOCALE_CHANGE, broadcastMLLocale, localeRecord } from '../mlLocale'
 
 const props = defineProps<FieldControlProps>()
 const emit = defineEmits<{ 'update:modelValue': [value: Record<string, string>] }>()
 
 const values = computed(() => localeRecord(props.modelValue))
+const enabledLocales = inject(FORM_ENABLED_LOCALES, null)
 const locales = computed(() => {
-  const keys = Object.keys(values.value)
-  return keys.length > 0 ? keys : ['en']
+  const codes = enabledLocales?.value
+  return codes && codes.length > 0 ? [...codes] : []
 })
 const activeLocale = ref(locales.value[0] ?? 'en')
 const copyFrom = ref('')
diff --git a/admin/src/components/form/formContext.ts b/admin/src/components/form/formContext.ts
index 6674365..6252bb5 100644
--- a/admin/src/components/form/formContext.ts
+++ b/admin/src/components/form/formContext.ts
@@ -16,6 +16,9 @@ export const FORM_PATCH: InjectionKey<(name: string, value: unknown) => void> =
 /** The form schema's locale (meta.locale). */
 export const FORM_LOCALE: InjectionKey<Readonly<Ref<string>>> = Symbol('summer.form.locale')
 
+/** Enabled content locales for ML controls (schema meta.enabledLocales). */
+export const FORM_ENABLED_LOCALES: InjectionKey<Readonly<Ref<readonly string[]>>> = Symbol('summer.form.enabledLocales')
+
 /**
  * The form controller's plugin assets: resolves once its scripts have loaded
  * or failed, with the failed URLs (pluginAssets.loadControllerAssets).
diff --git a/admin/src/components/form/formState.ts b/admin/src/components/form/formState.ts
index 2635d9b..0ecc0c4 100644
--- a/admin/src/components/form/formState.ts
+++ b/admin/src/components/form/formState.ts
@@ -92,8 +92,9 @@ export function presetValue(type: string, source: unknown): string {
     .replace(/^-+|-+$/g, '')
 }
 
-/** Initial values of a new record: schema defaults, toggles off, no ids. */
-export function initialValues(fields: FormField[]): AdminRecord {
+/** Initial values of a new record: schema defaults, toggles off, no ids.
+ * ML fields seed an empty string for every enabled locale. */
+export function initialValues(fields: FormField[], enabledLocales: readonly string[] = []): AdminRecord {
   const out: AdminRecord = {}
   for (const field of fields) {
     if (field.default !== undefined) {
@@ -103,12 +104,38 @@ export function initialValues(fields: FormField[]): AdminRecord {
     } else if (field.type === 'relation' && field.multiple) {
       out[field.name] = []
     } else if (field.type === 'mltext' || field.type === 'mlmarkdown') {
-      out[field.name] = {}
+      const seed: Record<string, string> = {}
+      for (const code of enabledLocales) {
+        seed[code] = ''
+      }
+      out[field.name] = seed
     }
   }
   return out
 }
 
+/** Content locales from form schema meta; empty when the writer is unpublished. */
+export function schemaEnabledLocales(meta: { enabledLocales?: readonly string[] } | null | undefined): readonly string[] {
+  return meta?.enabledLocales ?? []
+}
+
+/** Merge a GET/save ML value onto a seed map of every enabled locale. A host
+ * string becomes the first enabled locale; it never replaces sibling keys. */
+export function mergeMLValue(incoming: unknown, enabledLocales: readonly string[]): Record<string, string> {
+  const seeded: Record<string, string> = {}
+  for (const code of enabledLocales) {
+    seeded[code] = ''
+  }
+  if (typeof incoming === 'string') {
+    const fallback = enabledLocales[0]
+    if (fallback) {
+      seeded[fallback] = incoming
+    }
+    return seeded
+  }
+  return { ...seeded, ...localeRecord(incoming) }
+}
+
 /** D-10 422 details (field -> messages) as a string-list map. */
 export function fieldErrors(details: ErrorBody['details'] | undefined): Record<string, string[]> {
   const out: Record<string, string[]> = {}
diff --git a/admin/src/views/FormView.vue b/admin/src/views/FormView.vue
index 05e3a52..785b1c8 100644
--- a/admin/src/views/FormView.vue
+++ b/admin/src/views/FormView.vue
@@ -13,7 +13,7 @@ import { mapWinterUrl } from '../app/winterUrl'
 import FormErrorBanner from '../components/form/FormErrorBanner.vue'
 import FormGrid from '../components/form/FormGrid.vue'
 import FormTabs from '../components/form/FormTabs.vue'
-import { FORM_ASSETS, FORM_LOCALE, FORM_PATCH, FORM_SESSION, FORM_VALUES, createUploadGate } from '../components/form/formContext'
+import { FORM_ASSETS, FORM_ENABLED_LOCALES, FORM_LOCALE, FORM_PATCH, FORM_SESSION, FORM_VALUES, createUploadGate } from '../components/form/formContext'
 import { RELATION_MANAGER, needsRecord } from '../components/form/registry'
 import {
   DEFAULT_TAB,
@@ -22,8 +22,10 @@ import {
   fieldErrors,
   focusField,
   initialValues,
+  mergeMLValue,
   panelDomId,
   presetValue,
+  schemaEnabledLocales,
   snapshot,
   tabDomId,
   tabOf,
@@ -168,9 +170,16 @@ const dirty = computed(
 
 function adopt(record: RecordEnvelope | undefined): void {
   if (record) {
-    // A record response never carries a password, so every password field
-    // is empty again after a save (UI-SPEC S7).
-    values.value = { ...record.data }
+    const locales = schemaEnabledLocales(schema.value?.meta)
+    const next: AdminRecord = { ...record.data }
+    for (const field of fields.value) {
+      if (field.type === 'password') {
+        next[field.name] = ''
+      } else if (field.type === 'mltext' || field.type === 'mlmarkdown') {
+        next[field.name] = mergeMLValue(record.data[field.name], locales)
+      }
+    }
+    values.value = next
     labels.value = record.meta.labels ?? {}
   }
   saved.value = snapshot(editablePayload(fields.value, values.value, mode))
@@ -193,7 +202,7 @@ async function load(): Promise<void> {
     assetsReady = loadControllerAssets(controllerId, schema.value.assets)
   }
   if (schema.value && mode === 'create') {
-    values.value = initialValues(fields.value)
+    values.value = initialValues(fields.value, schemaEnabledLocales(schema.value.meta))
   }
   adopt(recordResult?.data)
   activeTab.value = tabs.value[0]?.key ?? DEFAULT_TAB
@@ -229,6 +238,7 @@ function update(name: string, value: unknown): void {
 provide(FORM_VALUES, computed(() => values.value))
 provide(FORM_PATCH, update)
 provide(FORM_LOCALE, computed(() => schema.value?.meta.locale || currentLocale.value))
+provide(FORM_ENABLED_LOCALES, computed(() => schemaEnabledLocales(schema.value?.meta)))
 provide(FORM_ASSETS, () => assetsReady)
 provide(FORM_SESSION, {
   key: sessionKey,
diff --git a/admin/tests/form/MLFields.test.ts b/admin/tests/form/MLFields.test.ts
index 0c9a02f..15f5e8a 100644
--- a/admin/tests/form/MLFields.test.ts
+++ b/admin/tests/form/MLFields.test.ts
@@ -1,10 +1,12 @@
 import { afterEach, beforeEach, describe, expect, it } from 'vitest'
 import { enableAutoUnmount, mount } from '@vue/test-utils'
+import { ref } from 'vue'
 import type { FormField } from '../../src/api/types'
 import MarkdownField from '../../src/components/form/fields/MarkdownField.vue'
 import MLMarkdownField from '../../src/components/form/fields/MLMarkdownField.vue'
 import MLTextField from '../../src/components/form/fields/MLTextField.vue'
-import { editablePayload } from '../../src/components/form/formState'
+import { FORM_ENABLED_LOCALES } from '../../src/components/form/formContext'
+import { editablePayload, initialValues, mergeMLValue } from '../../src/components/form/formState'
 import { isRegistered, rendererFor } from '../../src/components/form/registry'
 import { resetState } from '../helpers'
 
@@ -12,8 +14,23 @@ function field(type: string, name = 'title'): FormField {
   return { name, label: 'Title', type } as FormField
 }
 
+const enabledLocales = ref<readonly string[]>(['en', 'pl'])
+
+function mlMount(component: typeof MLTextField | typeof MLMarkdownField, props: Record<string, unknown>) {
+  return mount(component, {
+    props,
+    attachTo: document.body,
+    global: {
+      provide: {
+        [FORM_ENABLED_LOCALES as symbol]: enabledLocales,
+      },
+    },
+  })
+}
+
 beforeEach(() => {
   resetState()
+  enabledLocales.value = ['en', 'pl']
 })
 
 afterEach(() => {
@@ -45,13 +62,10 @@ describe('ML field registry and nested save body', () => {
   })
 
   it('edits the active locale and copies from another', async () => {
-    const wrapper = mount(MLTextField, {
-      props: {
-        field: field('mltext'),
-        modelValue: { en: 'Hello', pl: 'Witaj' },
-        controlId: 'f-title',
-      },
-      attachTo: document.body,
+    const wrapper = mlMount(MLTextField, {
+      field: field('mltext'),
+      modelValue: { en: 'Hello', pl: 'Witaj' },
+      controlId: 'f-title',
     })
     const input = wrapper.find('input')
     expect(input.element.value).toBe('Hello')
@@ -63,13 +77,15 @@ describe('ML field registry and nested save body', () => {
   })
 
   it('switches every ML control from one selector', async () => {
-    const title = mount(MLTextField, {
-      props: { field: field('mltext'), modelValue: { en: 'Hello', pl: 'Witaj' }, controlId: 'f-title' },
-      attachTo: document.body,
+    const title = mlMount(MLTextField, {
+      field: field('mltext'),
+      modelValue: { en: 'Hello', pl: 'Witaj' },
+      controlId: 'f-title',
     })
-    const body = mount(MLMarkdownField, {
-      props: { field: field('mlmarkdown', 'body'), modelValue: { en: 'EN', pl: 'PL' }, controlId: 'f-body' },
-      attachTo: document.body,
+    const body = mlMount(MLMarkdownField, {
+      field: field('mlmarkdown', 'body'),
+      modelValue: { en: 'EN', pl: 'PL' },
+      controlId: 'f-body',
     })
     expect(body.findComponent(MarkdownField).exists()).toBe(true)
     await title.find('[data-ml-locale]').setValue('pl')
@@ -92,4 +108,31 @@ describe('ML field registry and nested save body', () => {
     expect((window as unknown as { __ml_xss?: number }).__ml_xss).toBeUndefined()
     expect(wrapper.find('[data-markdown-preview-pane]').text()).toContain('<script>')
   })
+
+  it('seeds empty maps and lists every enabled locale on create', () => {
+    const fields = [field('mltext')]
+    const values = initialValues(fields, ['en', 'pl'])
+    expect(values.title).toEqual({ en: '', pl: '' })
+    const wrapper = mlMount(MLTextField, {
+      field: fields[0],
+      modelValue: values.title,
+      controlId: 'f-title',
+    })
+    expect(wrapper.findAll('[data-ml-locale] option').map((node) => node.text())).toEqual(['en', 'pl'])
+  })
+
+  it('keeps sibling locales when adopt merges a GET host string', async () => {
+    const fields = [field('mltext')]
+    const merged = mergeMLValue('Hello', ['en', 'pl'])
+    expect(merged).toEqual({ en: 'Hello', pl: '' })
+    const wrapper = mlMount(MLTextField, {
+      field: fields[0],
+      modelValue: merged,
+      controlId: 'f-title',
+    })
+    expect(wrapper.findAll('[data-ml-locale] option').map((node) => node.text())).toEqual(['en', 'pl'])
+    await wrapper.find('[data-ml-locale]').setValue('pl')
+    await wrapper.find('input').setValue('Witaj')
+    expect(wrapper.emitted('update:modelValue')?.at(-1)).toEqual([{ en: 'Hello', pl: 'Witaj' }])
+  })
 })
diff --git a/modules/cabana/crud.go b/modules/cabana/crud.go
index a30d93f..45a9868 100644
--- a/modules/cabana/crud.go
+++ b/modules/cabana/crud.go
@@ -441,6 +441,9 @@ func (s CRUDService) ShowRecord(ctx context.Context, cc *CompiledController, id
 		if err != nil {
 			return err
 		}
+		if err := hydrateMLRecord(ctx, tx, cc, s.writer, target, result.Data, "update"); err != nil {
+			return err
+		}
 		result.Meta.Actions, err = s.offeredRecordActions(withTx(ctx, tx), cc, target)
 		return err
 	})
@@ -700,7 +703,10 @@ func (s CRUDService) save(ctx context.Context, cc *CompiledController, id any, i
 			return err
 		}
 		result, err = projectFullRecord(ctx, tx, cc, target)
-		return err
+		if err != nil {
+			return err
+		}
+		return hydrateMLRecord(ctx, tx, cc, s.writer, target, result.Data, op)
 	})
 	if err != nil {
 		return RecordResult{}, err
diff --git a/modules/cabana/field_ml.go b/modules/cabana/field_ml.go
index df5c362..14e4419 100644
--- a/modules/cabana/field_ml.go
+++ b/modules/cabana/field_ml.go
@@ -12,11 +12,13 @@ const (
 	mlMarkdownFieldType = "mlmarkdown"
 )
 
-// TranslationWriter persists non-default locale values during a cabana save.
-// The interface lives in the framework so cabana never imports a plugin; a
-// host publishes an adapter at Boot. There is no standalone translate-write
+// TranslationWriter persists non-default locale values during a cabana save
+// and reads exact stored translations for Show/save hydration. The interface
+// lives in the framework so cabana never imports a plugin; a host publishes
+// an adapter at Boot. There is no standalone translate-read or translate-write
 // HTTP endpoint: writes run only inside a permissioned, scoped host save
-// transaction after the host row has a primary key.
+// transaction after the host row has a primary key, and reads run on the
+// same adapter after projectFullRecord.
 type TranslationWriter interface {
 	// DefaultLocale is the host-column locale.
 	DefaultLocale(ctx context.Context, tx *gorm.DB) (string, error)
@@ -25,6 +27,11 @@ type TranslationWriter interface {
 	// WriteTranslated stores field in locale for model. locale is never the
 	// default; cabana already filled the host scalar.
 	WriteTranslated(ctx context.Context, tx *gorm.DB, model any, field, locale, value string) error
+	// TranslatedExact returns the stored value for field in locale. ok is
+	// false when the non-default key is missing. It must not apply D-11
+	// fallback: empty admin values stay empty. The default locale still
+	// reads the host column.
+	TranslatedExact(ctx context.Context, tx *gorm.DB, model any, field, locale string) (string, bool, error)
 }
 
 // mlValue is one multilingual field lifted from a save body.
@@ -158,3 +165,68 @@ func applyMLTranslations(ctx context.Context, tx *gorm.DB, writer TranslationWri
 	}
 	return nil
 }
+
+// hydrateMLRecord replaces host scalars of declared mltext/mlmarkdown fields
+// in a Show/save RecordResult.Data map with a locale→text map for every
+// enabled code. The default locale is the projected host column; other codes
+// come from TranslatedExact; a missing non-default code is an empty string,
+// never D-11 fallback. It is a no-op when writer is nil and is not used from
+// list row projection.
+func hydrateMLRecord(ctx context.Context, tx *gorm.DB, cc *CompiledController, writer TranslationWriter, model any, data map[string]any, op string) error {
+	if writer == nil || cc == nil || cc.Form == nil || data == nil {
+		return nil
+	}
+	var names []string
+	for _, field := range cc.Form.Fields {
+		if !mlFieldType(field.Type) || !contextAllows(cc, field.Name, op) {
+			continue
+		}
+		names = append(names, field.Name)
+	}
+	if len(names) == 0 {
+		return nil
+	}
+	defaultLocale, err := writer.DefaultLocale(ctx, tx)
+	if err != nil || defaultLocale == "" {
+		return fmt.Errorf("cabana: default locale: %w", err)
+	}
+	codes, err := writer.EnabledLocales(ctx, tx)
+	if err != nil {
+		return fmt.Errorf("cabana: enabled locales: %w", err)
+	}
+	for _, name := range names {
+		host := hostScalarString(data[name])
+		out := make(map[string]string, len(codes))
+		for _, code := range codes {
+			if code == defaultLocale {
+				out[code] = host
+				continue
+			}
+			text, ok, err := writer.TranslatedExact(ctx, tx, model, name, code)
+			if err != nil {
+				return err
+			}
+			if !ok {
+				out[code] = ""
+				continue
+			}
+			out[code] = text
+		}
+		data[name] = out
+	}
+	return nil
+}
+
+func hostScalarString(v any) string {
+	if v == nil {
+		return ""
+	}
+	switch t := v.(type) {
+	case string:
+		return t
+	case []byte:
+		return string(t)
+	default:
+		return fmt.Sprint(t)
+	}
+}
diff --git a/modules/cabana/http.go b/modules/cabana/http.go
index bb068b5..bfb50bb 100644
--- a/modules/cabana/http.go
+++ b/modules/cabana/http.go
@@ -709,10 +709,16 @@ func (s *service) formSchema(w http.ResponseWriter, r *http.Request) {
 		}
 		view.Fields = kept
 		view.Assets = s.controllerAssets(cc)
+		if codes := s.enabledContentLocales(r.Context()); len(codes) > 0 {
+			view.Meta.EnabledLocales = append([]string(nil), codes...)
+		}
 		meta := map[string]any{}
 		if view.Meta.Locale != "" {
 			meta["locale"] = view.Meta.Locale
 		}
+		if len(view.Meta.EnabledLocales) > 0 {
+			meta["enabledLocales"] = view.Meta.EnabledLocales
+		}
 		WriteData(w, http.StatusOK, view, meta)
 	})
 }
@@ -939,6 +945,29 @@ func (s *service) crud() (CRUDService, error) {
 	return svc, nil
 }
 
+// enabledContentLocales is TranslationWriter.EnabledLocales after the same
+// Lookup crud() uses. Empty when the adapter is unpublished or the query
+// fails; list schemas never call this.
+func (s *service) enabledContentLocales(ctx context.Context) []string {
+	if s == nil || s.app == nil {
+		return nil
+	}
+	writer, ok := s.app.Lookup[TranslationWriter]()
+	if !ok || writer == nil {
+		return nil
+	}
+	db, err := s.db()
+	if err != nil {
+		return nil
+	}
+	codes, err := writer.EnabledLocales(ctx, db)
+	if err != nil {
+		slog.Error("cabana: enabled locales", "error", err)
+		return nil
+	}
+	return codes
+}
+
 func (s *service) list(w http.ResponseWriter, r *http.Request) {
 	s.protect(w, r, func(cc *CompiledController) {
 		db, err := s.db()
diff --git a/modules/cabana/ml_smoke_test.go b/modules/cabana/ml_smoke_test.go
index 3fdccb9..1a235da 100644
--- a/modules/cabana/ml_smoke_test.go
+++ b/modules/cabana/ml_smoke_test.go
@@ -95,6 +95,25 @@ func (w *recordingWriter) WriteTranslated(_ context.Context, _ *gorm.DB, model a
 	return nil
 }
 
+func (w *recordingWriter) TranslatedExact(_ context.Context, _ *gorm.DB, model any, field, locale string) (string, bool, error) {
+	if locale == w.defaultLocale {
+		post, _ := model.(*mlPost)
+		if post == nil {
+			return "", false, nil
+		}
+		return post.Title, true, nil
+	}
+	if w.attrs == nil {
+		return "", false, nil
+	}
+	vals := w.attrs[locale]
+	if vals == nil {
+		return "", false, nil
+	}
+	text, ok := vals[field]
+	return text, ok, nil
+}
+
 func mlFS() fstest.MapFS {
 	return fstest.MapFS{
 		"controllers/posts/config_list.yaml": &fstest.MapFile{Data: []byte(mlListConfig)},
@@ -181,8 +200,13 @@ func TestMLNestedSaveSmoke(t *testing.T) {
 		if err != nil {
 			t.Fatalf("create: %v", err)
 		}
-		if rec["title"] != "Hello" {
-			t.Fatalf("projected title = %#v, want Hello", rec["title"])
+		if rec["title"] != nil {
+			got, ok := rec["title"].(map[string]string)
+			if !ok || got["en"] != "Hello" || got["pl"] != "Witaj" {
+				t.Fatalf("projected title = %#v, want hydrated en+pl map", rec["title"])
+			}
+		} else {
+			t.Fatalf("projected title = %#v, want hydrated en+pl map", rec["title"])
 		}
 		var row mlPost
 		if err := db.First(&row).Error; err != nil {
diff --git a/modules/cabana/ml_test.go b/modules/cabana/ml_test.go
index e68771f..c39057f 100644
--- a/modules/cabana/ml_test.go
+++ b/modules/cabana/ml_test.go
@@ -3,6 +3,7 @@ package cabana
 import (
 	"context"
 	"errors"
+	"reflect"
 	"strings"
 	"testing"
 
@@ -66,7 +67,13 @@ func TestMLNestedSave(t *testing.T) {
 	if err != nil {
 		t.Fatalf("create: %v", err)
 	}
-	if rec["title"] != "Hello" {
+	if rec["title"] != nil {
+		want := map[string]string{"en": "Hello", "pl": "Witaj"}
+		got, ok := rec["title"].(map[string]string)
+		if !ok || !reflect.DeepEqual(got, want) {
+			t.Fatalf("projected title = %#v", rec["title"])
+		}
+	} else {
 		t.Fatalf("projected title = %#v", rec["title"])
 	}
 	var row mlPost
@@ -97,6 +104,55 @@ func TestMLNestedSave(t *testing.T) {
 	}
 }
 
+func TestMLHydration(t *testing.T) {
+	_, db := newListService(t)
+	if err := db.Migrator().DropTable(&mlPost{}); err != nil {
+		t.Fatal(err)
+	}
+	if err := db.AutoMigrate(&mlPost{}); err != nil {
+		t.Fatal(err)
+	}
+	writer := &recordingWriter{defaultLocale: "en", enabled: []string{"en", "pl"}}
+	svc := CRUDService{DB: db, writer: writer}
+	cc := mlCompiled(t)
+	ctx := context.Background()
+
+	created, err := svc.CreateRecord(ctx, cc, RecordInput{Body: map[string]any{
+		"title": map[string]any{"en": "Hello", "pl": "Witaj"},
+	}})
+	if err != nil {
+		t.Fatalf("create: %v", err)
+	}
+	got, ok := created.Data["title"].(map[string]string)
+	if !ok || got["en"] != "Hello" || got["pl"] != "Witaj" {
+		t.Fatalf("create title = %#v", created.Data["title"])
+	}
+
+	shown, err := svc.ShowRecord(ctx, cc, created.Data["id"])
+	if err != nil {
+		t.Fatalf("show: %v", err)
+	}
+	got, ok = shown.Data["title"].(map[string]string)
+	if !ok || got["en"] != "Hello" || got["pl"] != "Witaj" {
+		t.Fatalf("show title = %#v", shown.Data["title"])
+	}
+
+	englishOnly := &recordingWriter{defaultLocale: "en", enabled: []string{"en", "pl"}}
+	svcOnly := CRUDService{DB: db, writer: englishOnly}
+	row := mlPost{Title: "Hello"}
+	if err := db.Create(&row).Error; err != nil {
+		t.Fatal(err)
+	}
+	shown, err = svcOnly.ShowRecord(ctx, cc, row.ID)
+	if err != nil {
+		t.Fatalf("show english-only: %v", err)
+	}
+	got, ok = shown.Data["title"].(map[string]string)
+	if !ok || got["en"] != "Hello" || got["pl"] != "" {
+		t.Fatalf("english-only title = %#v", shown.Data["title"])
+	}
+}
+
 func TestML(t *testing.T) {
 	t.Run("writer failure rolls back host write", func(t *testing.T) {
 		_, db := newListService(t)
diff --git a/modules/cabana/schema_types.go b/modules/cabana/schema_types.go
index 164e401..e5c327c 100644
--- a/modules/cabana/schema_types.go
+++ b/modules/cabana/schema_types.go
@@ -227,8 +227,11 @@ type FormRedirect struct {
 }
 
 // FormMeta reports the locale selected for a schema response.
+// EnabledLocales lists content locales for ML fields when a TranslationWriter
+// is published; omitempty keeps list schemas without the key.
 type FormMeta struct {
-	Locale string `json:"locale"`
+	Locale         string   `json:"locale"`
+	EnabledLocales []string `json:"enabledLocales,omitempty"`
 }
 
 // FormField is one Winter field in source order. JSON keys keep Winter spelling.