CDD-3119 Add a new SimpleMenu model.

This is a simplified version of the current Menu model where menus are
now just simple links with a title.

Author: David Logie

cms/dashboard/management/commands/build_cms_site_helpers/__init__.py

@@ -11,4 +11,4 @@
     create_whats_new_child_entry,
     create_feedback_page,
 )
-from .menu import create_menu_snippet
+from .menu import create_menu_snippet, create_simplemenu_snippet

cms/dashboard/management/commands/build_cms_site_helpers/menu.py

@@ -2,7 +2,7 @@
 from cms.composite.models import CompositePage
 from cms.home.models import LandingPage
 from cms.metrics_documentation.models import MetricsDocumentationParentPage
-from cms.snippets.models import Menu
+from cms.snippets.models import Menu, SimpleMenu
 from cms.topic.models import TopicPage
 from cms.whats_new.models import WhatsNewParentPage
 
@@ -172,3 +172,33 @@ def _create_menu_data() -> list[dict]:
             "id": "dcd6d76c-a3b3-4b44-8326-8177d609b50b",
         }
     ]
+
+
+def create_simplemenu_snippet():
+    SimpleMenu.objects.create(
+        internal_label="Primary navigation",
+        is_active=True,
+        body=_create_simplemenu_data(),
+    )
+
+
+def _create_simplemenu_data() -> list[dict]:
+    covid_page = TopicPage.objects.get(slug="covid-19")
+    flu_page = TopicPage.objects.get(slug="influenza")
+
+    return [
+        {
+            "type": "link",
+            "value": {"title": "COVID", "page": covid_page.id, "html_url": covid_page.full_url},
+            "id": "d8e270c7-f3d7-41cf-8d7c-c2bbe62ed71d",
+        },
+        {
+            "type": "link",
+            "value": {
+                "title": "What's new",
+                "page": flu_page.id,
+                "html_url": flu_page.full_url,
+            },
+            "id": "021352b9-d606-48ee-b942-1739ccec9e03",
+        },
+    ]

cms/snippets/managers/menu.py

@@ -61,3 +61,63 @@ def is_menu_overriding_currently_active_menu(self, menu) -> bool:
 
         active_menu = self.get_active_menu()
         return bool(menu.is_active and menu != active_menu)
+
+
+class SimpleMenuQuerySet(models.QuerySet):
+    """Custom queryset which can be used by the `SimpleMenu"""
+
+    def get_active_menus(self) -> Self:
+        """Gets the all currently active `SimpleMenu`.
+
+        Returns:
+            QuerySet: A queryset of the active banners:
+                Examples:
+                    `<SimpleMenuQuerySet [<Menu>]>`
+        """
+        return self.filter(is_active=True)
+
+
+class SimpleMenuManager(models.Manager):
+    """Custom model manager class for the `SimpleMenu` model"""
+
+    def get_queryset(self) -> SimpleMenuQuerySet:
+        return SimpleMenuQuerySet(model=self.model, using=self.db)
+
+    def has_active_menu(self) -> bool:
+        """Checks if there is already a `SimpleMenu` which is active
+
+        Returns:
+            True if there is a `SimpleMenu` which has `is_active` set to True.
+            False otherwise.
+
+        """
+        return self.get_queryset().get_active_menus().exists()
+
+    def get_active_menu(self):
+        """Gets the currently active `SimpleMenu`.
+
+        Returns:
+            The currently active `SimpleMenu` if available.
+            If there is no `SimpleMenu` with `is_active` set to True,
+            then None is returned.
+
+        """
+        return self.get_queryset().get_active_menus().first()
+
+    def is_menu_overriding_currently_active_menu(self, menu) -> bool:
+        """Determines if the given `menu` is trying to override an existing active `SimpleMenu`
+
+        Args:
+            menu: The current `SimpleMenu` object which is being evaluated
+
+        Returns:
+            True if the given `menu` is trying to override
+            an existing active `SimpleMenu`. False otherwise.
+
+        """
+        has_existing_active_menu: bool = self.has_active_menu()
+        if not has_existing_active_menu:
+            return False
+
+        active_menu = self.get_active_menu()
+        return bool(menu.is_active and menu != active_menu)

cms/snippets/migrations/0014_simplemenu.py

@@ -0,0 +1,72 @@
+# Generated by Django 5.2.11 on 2026-03-19 14:48
+
+import django.db.models.deletion
+import wagtail.fields
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("snippets", "0013_remove_geography_code_field_from_wha_button"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="SimpleMenu",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "internal_label",
+                    models.TextField(
+                        help_text="\nA label to associate with this particular menu design.\nNote that this label is private / internal and is not used on the dashboard.\nThis is purely to help identify each of the constructed menu designs.\n"
+                    ),
+                ),
+                (
+                    "is_active",
+                    models.BooleanField(
+                        default=False,
+                        help_text="\nWhether to activate this menu. \nNote that only 1 menu can be active at a time.\nTo switch from 1 active menu to another, \nyou must deactivate the 1st menu and save it before activating and saving the 2nd menu.\n",
+                    ),
+                ),
+                (
+                    "body",
+                    wagtail.fields.StreamField(
+                        [("link", 2)],
+                        block_lookup={
+                            0: (
+                                "wagtail.blocks.TextBlock",
+                                (),
+                                {
+                                    "help_text": "\nThe title to display for this menu item.\nAs a general rule of thumb, the title length should be no longer than 60 characters.\n",
+                                    "required": True,
+                                },
+                            ),
+                            1: (
+                                "wagtail.blocks.PageChooserBlock",
+                                ("wagtailcore.Page",),
+                                {
+                                    "on_delete": django.db.models.deletion.CASCADE,
+                                    "related_name": "+",
+                                },
+                            ),
+                            2: (
+                                "wagtail.blocks.StructBlock",
+                                [[("title", 0), ("page", 1)]],
+                                {},
+                            ),
+                        },
+                        help_text="\nThe menu is constructed from a grid system of rows and columns.\nThere can be any number of rows and columns.\nBut each column should have at least 1 link.\n",
+                    ),
+                ),
+            ],
+        ),
+    ]

cms/snippets/models/__init__.py

@@ -2,4 +2,4 @@
 from .external_button import ExternalButton, ExternalButtonTypes, ExternalButtonIcons
 from .wha_button import WeatherAlertButton, WeatherAlertButtonTypes
 from .global_banner import GlobalBanner
-from .menu_builder.menu import Menu
+from .menu_builder.menu import Menu, SimpleMenu

cms/snippets/models/menu_builder/__init__.py

@@ -1 +1 @@
-from .menu import Menu
+from .menu import Menu, SimpleMenu

cms/snippets/models/menu_builder/help_texts.py

@@ -45,3 +45,11 @@
 Note that this label is private / internal and is not used on the dashboard.
 This is purely to help identify each of the constructed menu designs.
 """
+
+SIMPLEMENU_HELP_TEXT = """
+The title to display for this menu item.
+"""
+
+SIMPLEMENU_BODY_TEXT = """
+Links to display in the menu.
+"""

cms/snippets/models/menu_builder/menu.py

@@ -1,11 +1,13 @@
 from django.core.exceptions import ValidationError
 from django.db import models
+from wagtail import fields
 from wagtail.admin.panels.field_panel import FieldPanel
 from wagtail.snippets.models import register_snippet
 
-from cms.snippets.managers.menu import MenuManager
+from cms.snippets.managers.menu import MenuManager, SimpleMenuManager
 from cms.snippets.models.menu_builder import help_texts
 from cms.snippets.models.menu_builder.dynamic_content import ALLOWABLE_BODY_CONTENT
+from cms.snippets.models.menu_builder.menu_link import SimpleMenuLink
 
 
 class MultipleMenusActiveError(ValidationError):
@@ -39,3 +41,28 @@ def clean(self) -> None:
     def _raise_error_if_trying_to_enable_multiple_menus(self) -> None:
         if Menu.objects.is_menu_overriding_currently_active_menu(menu=self):
             raise MultipleMenusActiveError
+
+
+@register_snippet
+class SimpleMenu(models.Model):
+    internal_label = models.TextField(help_text=help_texts.MENU_INTERNAL_LABEL)
+    is_active = models.BooleanField(default=False, help_text=help_texts.MENU_IS_ACTIVE)
+    body = fields.StreamField(
+        block_types=[("link", SimpleMenuLink())],
+        use_json_field=True,
+        help_text=help_texts.SIMPLEMENU_BODY_TEXT,
+    )
+
+    objects = SimpleMenuManager()
+
+    def __str__(self) -> str:
+        prefix = "Active" if self.is_active else "Inactive"
+        return f"({prefix}) - {self.internal_label}"
+
+    def clean(self) -> None:
+        super().clean()
+        self._raise_error_if_trying_to_enable_multiple_menus()
+
+    def _raise_error_if_trying_to_enable_multiple_menus(self) -> None:
+        if SimpleMenu.objects.is_menu_overriding_currently_active_menu(menu=self):
+            raise MultipleMenusActiveError

cms/snippets/models/menu_builder/menu_link.py

@@ -56,3 +56,39 @@ def get_prep_value(self, value: StructValue) -> dict[str, str | int]:
         prep_value["html_url"] = page.full_url
 
         return prep_value
+
+
+class SimpleMenuLink(blocks.StructBlock):
+    title = blocks.TextBlock(
+        required=True,
+        help_text=help_texts.MENU_LINK_HELP_TEXT,
+    )
+    page = blocks.PageChooserBlock(
+        "wagtailcore.Page",
+        related_name="+",
+        on_delete=models.CASCADE,
+    )
+
+    class Meta:
+        icon = "link"
+
+    def get_prep_value(self, value: StructValue) -> dict[str, str | int]:
+        """Adds the `html_url` of each page to the returned value
+
+        Args:
+            `value`: The inbound enriched `StructValue`
+                containing the values associated with
+                this `SimpleMenuLink` object
+
+        Returns:
+            Dict containing the keys as dictated by the
+            `SimpleMenuLink`. With the addition of the injected
+            `html_url` value for the selected page.
+
+        """
+        prep_value: dict[str, str | int] = super().get_prep_value(value=value)
+        page: Page = value["page"]
+        page: type[UKHSAPage] = page.specific
+        prep_value["html_url"] = page.full_url
+
+        return prep_value

cms/snippets/serializers/__init__.py

@@ -4,7 +4,12 @@
     InternalButtonSerializer,
 )
 from .global_banner import (
-    GlobalBannerSerializer,
     GlobalBannerResponseSerializer,
+    GlobalBannerSerializer,
+)
+from .menu import (
+    MenuResponseSerializer,
+    MenuSerializer,
+    SimpleMenuResponseSerializer,
+    SimpleMenuSerializer,
 )
-from .menu import MenuSerializer, MenuResponseSerializer