From eb4e1ad198c3375e27a7504ca422deea882d4fc1 Mon Sep 17 00:00:00 2001
From: Jake Howard <git@theorangeone.net>
Date: Fri, 24 May 2024 21:37:51 +0100
Subject: [PATCH] Allow the admin to be enabled

---
 yamdl_playground/core/admin.py      | 29 +++++++++++++++++++++++++++++
 yamdl_playground/core/apps.py       |  5 +++++
 yamdl_playground/core/middleware.py | 26 ++++++++++++++++++++++++++
 yamdl_playground/settings.py        | 26 ++++++++++++++++++++++++++
 yamdl_playground/urls.py            |  6 ++++++
 5 files changed, 92 insertions(+)
 create mode 100644 yamdl_playground/core/admin.py
 create mode 100644 yamdl_playground/core/middleware.py

diff --git a/yamdl_playground/core/admin.py b/yamdl_playground/core/admin.py
new file mode 100644
index 0000000..1e18b7e
--- /dev/null
+++ b/yamdl_playground/core/admin.py
@@ -0,0 +1,29 @@
+from django.contrib import admin
+from .models import Page
+
+class PageAdmin(admin.ModelAdmin):
+    list_display = ["id", "title", "slug"]
+    list_display_links = ["id", "title"]
+    sortable_by = ["title"]
+    ordering = ["title"]
+
+    def has_add_permission(self, request, obj=None):
+        return False
+
+    def has_delete_permission(self, request, obj=None):
+        return False
+
+    def has_change_permission(self, request, obj=None):
+        return False
+
+    def get_readonly_fields(self, request, obj=None):
+        return [field.name for field in (obj._meta.fields + obj._meta.many_to_many)]
+
+    @admin.options.csrf_protect_m
+    def changeform_view(self, *args, **kwargs):
+        """
+        Override to prevent issues with `db_for_write`
+        """
+        return self._changeform_view(*args, **kwargs)
+
+admin.site.register(Page, PageAdmin)
diff --git a/yamdl_playground/core/apps.py b/yamdl_playground/core/apps.py
index 54314c8..5ed3227 100644
--- a/yamdl_playground/core/apps.py
+++ b/yamdl_playground/core/apps.py
@@ -3,6 +3,7 @@ from django.db import connections
 from django.db.models.signals import post_save
 import warnings
 from django.utils.html import strip_tags
+from django.core.management import call_command
 
 
 class CoreConfig(AppConfig):
@@ -19,6 +20,10 @@ class CoreConfig(AppConfig):
             with warnings.catch_warnings():
                 # Django doesn't like running DB queries during app initialization
                 warnings.filterwarnings("ignore", module="django.db", category=RuntimeWarning)
+
+                # Run migrations, if there are any
+                call_command("migrate", verbosity=0, no_input=True)
+
                 with connection.cursor() as cursor:
                     cursor.execute("CREATE VIRTUAL TABLE search_index USING fts5(body, content='');")
 
diff --git a/yamdl_playground/core/middleware.py b/yamdl_playground/core/middleware.py
new file mode 100644
index 0000000..f545f44
--- /dev/null
+++ b/yamdl_playground/core/middleware.py
@@ -0,0 +1,26 @@
+from django.contrib.auth.models import AnonymousUser
+
+class FakeUser(AnonymousUser):
+    is_authenticated = True
+    is_anonymous = False
+    is_staff = True
+    is_active = True
+    is_superuser = True
+    username = "Fake user"
+
+    def has_module_perms(self, module):
+        # Don't allow access to the 'auth' app
+        # Also stops it showing up in the admin
+        return module not in {"auth"}
+
+    def has_perm(self, perm, obj=None):
+        return True
+
+class FakeAuthenticationMiddleware:
+    def __init__(self, get_response):
+        self.get_response = get_response
+
+    def __call__(self, request):
+        # HACK: Inject our user in to user caches
+        request._cached_user = request._acached_user = FakeUser()
+        return self.get_response(request)
diff --git a/yamdl_playground/settings.py b/yamdl_playground/settings.py
index 0aae9a2..3a12eaa 100644
--- a/yamdl_playground/settings.py
+++ b/yamdl_playground/settings.py
@@ -11,6 +11,7 @@ https://docs.djangoproject.com/en/5.0/ref/settings/
 """
 
 from pathlib import Path
+import os
 
 # Build paths inside the project like this: BASE_DIR / 'subdir'.
 BASE_DIR = Path(__file__).resolve().parent.parent
@@ -188,3 +189,28 @@ LOGGING = {
 DEBUG_TOOLBAR_CONFIG = {
     "SHOW_TOOLBAR_CALLBACK": "yamdl_playground.core.utils.show_debug_toolbar"
 }
+
+
+if "ENABLE_ADMIN" in os.environ:
+    INSTALLED_APPS.extend([
+        'django.contrib.admin',
+        'django.contrib.auth',
+        'django.contrib.contenttypes',
+        'django.contrib.messages',
+        'django.contrib.sessions',
+    ])
+
+    MIDDLEWARE.extend([
+        'yamdl_playground.core.middleware.FakeAuthenticationMiddleware',
+        'django.contrib.sessions.middleware.SessionMiddleware',
+        'django.contrib.auth.middleware.AuthenticationMiddleware',
+        'django.contrib.messages.middleware.MessageMiddleware',
+    ])
+
+    # To make sure it's definitely working
+    AUTHENTICATION_BACKENDS = []
+
+    TEMPLATES[0]["OPTIONS"]["context_processors"].extend([
+        'django.contrib.auth.context_processors.auth',
+        'django.contrib.messages.context_processors.messages',
+    ])
diff --git a/yamdl_playground/urls.py b/yamdl_playground/urls.py
index 93f54fb..2d12acc 100644
--- a/yamdl_playground/urls.py
+++ b/yamdl_playground/urls.py
@@ -16,6 +16,7 @@ Including another URLconf
 """
 from django.urls import path, include
 from .core import views
+from django.apps import apps
 
 urlpatterns = [
     path("search/", views.search),
@@ -23,3 +24,8 @@ urlpatterns = [
     path("__debug__/", include("debug_toolbar.urls")),
     path("cached-content/<slug:slug>/", views.cached_content)
 ]
+
+if apps.is_installed("django.contrib.admin"):
+    from django.contrib import admin
+
+    urlpatterns.append(path("admin/", admin.site.urls))