Fixed #8261 -- ModelAdmin hook for customising the "show on site" button

``ModelAdmin.view_on_site`` defines wether to show a link to the object on the
admin detail page. If ``True``, cleverness (i.e. ``Model.get_absolute_url``) is
used to get the url. If it's a callable, the callable is called with the object
as the only parameter. If ``False``, not link is displayed.

With the aim of maitaining backwards compatibility, ``True`` is the default.

4 files changed, 201 insertions, 3 deletions

diff --git a/tests/admin_views/admin.py b/tests/admin_views/admin.py
index 7dd6c91e71..36b35aeefe 100644
--- a/tests/admin_views/admin.py
+++ b/tests/admin_views/admin.py
@@ -31,7 +31,7 @@ from .models import (Article, Chapter, Account, Media, Child, Parent, Picture,
     AdminOrderedCallable, Report, Color2, UnorderedObject, MainPrepopulated,
     RelatedPrepopulated, UndeletableObject, UnchangeableObject, UserMessenger, Simple, Choice,
     ShortMessage, Telegram, FilteredManager, EmptyModelHidden,
-    EmptyModelVisible, EmptyModelMixin)
+    EmptyModelVisible, EmptyModelMixin, State, City, Restaurant, Worker)
 
 
 def callable_year(dt_value):
@@ -74,6 +74,7 @@ class ChapterXtra1Admin(admin.ModelAdmin):
 class ArticleAdmin(admin.ModelAdmin):
     list_display = ('content', 'date', callable_year, 'model_year', 'modeladmin_year')
     list_filter = ('date', 'section')
+    view_on_site = False
     fieldsets = (
         ('Some fields', {
             'classes': ('collapse',),
@@ -735,6 +736,35 @@ class EmptyModelMixinAdmin(admin.ModelAdmin):
     form = FormWithVisibleAndHiddenField
     fieldsets = EmptyModelVisibleAdmin.fieldsets
 
+class CityInlineAdmin(admin.TabularInline):
+    model = City
+    view_on_site = False
+
+class StateAdmin(admin.ModelAdmin):
+    inlines = [CityInlineAdmin]
+
+class RestaurantInlineAdmin(admin.TabularInline):
+    model = Restaurant
+    view_on_site = True
+
+class CityAdmin(admin.ModelAdmin):
+    inlines = [RestaurantInlineAdmin]
+    view_on_site = True
+
+class WorkerAdmin(admin.ModelAdmin):
+    def view_on_site(self, obj):
+        return '/worker/%s/%s/' % (obj.surname, obj.name)
+
+class WorkerInlineAdmin(admin.TabularInline):
+    model = Worker
+
+    def view_on_site(self, obj):
+        return '/worker_inline/%s/%s/' % (obj.surname, obj.name)
+
+class RestaurantAdmin(admin.ModelAdmin):
+    inlines = [WorkerInlineAdmin]
+    view_on_site = False
+
 site = admin.AdminSite(name="admin")
 site.register(Article, ArticleAdmin)
 site.register(CustomArticle, CustomArticleAdmin)
@@ -785,6 +815,10 @@ site.register(MainPrepopulated, MainPrepopulatedAdmin)
 site.register(UnorderedObject, UnorderedObjectAdmin)
 site.register(UndeletableObject, UndeletableObjectAdmin)
 site.register(UnchangeableObject, UnchangeableObjectAdmin)
+site.register(State, StateAdmin)
+site.register(City, CityAdmin)
+site.register(Restaurant, RestaurantAdmin)
+site.register(Worker, WorkerAdmin)
 
 # We intentionally register Promo and ChapterXtra1 but not Chapter nor ChapterXtra2.
 # That way we cover all four cases:
diff --git a/tests/admin_views/fixtures/admin-views-restaurants.xml b/tests/admin_views/fixtures/admin-views-restaurants.xml
new file mode 100644
index 0000000000..81e67ee8d0
--- /dev/null
+++ b/tests/admin_views/fixtures/admin-views-restaurants.xml
@@ -0,0 +1,63 @@
+<?xml version="1.0" encoding="utf-8"?>
+<django-objects version="1.0">
+    <object pk="1" model="admin_views.state">
+        <field type="CharField" name="name">New York</field>
+    </object>
+    <object pk="2" model="admin_views.state">
+        <field type="CharField" name="name">Illinois</field>
+    </object>
+    <object pk="3" model="admin_views.state">
+        <field type="CharField" name="name">California</field>
+    </object>
+    <object pk="1" model="admin_views.city">
+        <field to="admin_views.state" name="state" rel="ManyToOneRel">1</field>
+        <field type="CharField" name="name">New York</field>
+    </object>
+    <object pk="2" model="admin_views.city">
+        <field to="admin_views.state" name="state" rel="ManyToOneRel">2</field>
+        <field type="CharField" name="name">Chicago</field>
+    </object>
+    <object pk="3" model="admin_views.city">
+        <field to="admin_views.state" name="state" rel="ManyToOneRel">3</field>
+        <field type="CharField" name="name">San Francisco</field>
+    </object>
+    <object pk="1" model="admin_views.restaurant">
+        <field to="admin_views.city" name="city" rel="ManyToOneRel">1</field>
+        <field type="CharField" name="name">Italian Pizza</field>
+    </object>
+    <object pk="2" model="admin_views.restaurant">
+        <field to="admin_views.city" name="city" rel="ManyToOneRel">1</field>
+        <field type="CharField" name="name">Boulevard</field>
+    </object>
+    <object pk="3" model="admin_views.restaurant">
+        <field to="admin_views.city" name="city" rel="ManyToOneRel">2</field>
+        <field type="CharField" name="name">Chinese Dinner</field>
+    </object>
+    <object pk="4" model="admin_views.restaurant">
+        <field to="admin_views.city" name="city" rel="ManyToOneRel">2</field>
+        <field type="CharField" name="name">Angels</field>
+    </object>
+    <object pk="5" model="admin_views.restaurant">
+        <field to="admin_views.city" name="city" rel="ManyToOneRel">2</field>
+        <field type="CharField" name="name">Take Away</field>
+    </object>
+    <object pk="6" model="admin_views.restaurant">
+        <field to="admin_views.city" name="city" rel="ManyToOneRel">3</field>
+        <field type="CharField" name="name">The Unknown Restaurant</field>
+    </object>
+    <object pk="1" model="admin_views.worker">
+        <field to="admin_views.restaurant" name="work_at" rel="ManyToOneRel">1</field>
+        <field type="CharField" name="name">Mario</field>
+        <field type="CharField" name="surname">Rossi</field>
+    </object>
+    <object pk="2" model="admin_views.worker">
+        <field to="admin_views.restaurant" name="work_at" rel="ManyToOneRel">1</field>
+        <field type="CharField" name="name">Antonio</field>
+        <field type="CharField" name="surname">Bianchi</field>
+    </object>
+    <object pk="3" model="admin_views.worker">
+        <field to="admin_views.restaurant" name="work_at" rel="ManyToOneRel">1</field>
+        <field type="CharField" name="name">John</field>
+        <field type="CharField" name="surname">Doe</field>
+    </object>
+</django-objects>
diff --git a/tests/admin_views/models.py b/tests/admin_views/models.py
index bab144e6b5..67f3b4216a 100644
--- a/tests/admin_views/models.py
+++ b/tests/admin_views/models.py
@@ -717,3 +717,19 @@ class EmptyModelHidden(models.Model):
 
 class EmptyModelMixin(models.Model):
     """ See ticket #11277. """
+
+class State(models.Model):
+    name = models.CharField(max_length=100)
+
+class City(models.Model):
+    state = models.ForeignKey(State)
+    name = models.CharField(max_length=100)
+
+class Restaurant(models.Model):
+    city = models.ForeignKey(City)
+    name = models.CharField(max_length=100)
+
+class Worker(models.Model):
+    work_at = models.ForeignKey(Restaurant)
+    name = models.CharField(max_length=50)
+    surname = models.CharField(max_length=50)
diff --git a/tests/admin_views/tests.py b/tests/admin_views/tests.py
index 16fea943f9..d5232fb8f2 100644
--- a/tests/admin_views/tests.py
+++ b/tests/admin_views/tests.py
@@ -9,6 +9,7 @@ import unittest
 from django.conf import settings, global_settings
 from django.core import mail
 from django.core.files import temp as tempfile
+from django.core.exceptions import ImproperlyConfigured
 from django.core.urlresolvers import reverse, NoReverseMatch
 # Register auth models with the admin.
 from django.contrib.auth import get_permission_codename
@@ -48,8 +49,8 @@ from .models import (Article, BarAccount, CustomArticle, EmptyModel, FooAccount,
     AdminOrderedModelMethod, AdminOrderedAdminMethod, AdminOrderedCallable,
     Report, MainPrepopulated, RelatedPrepopulated, UnorderedObject,
     Simple, UndeletableObject, UnchangeableObject, Choice, ShortMessage,
-    Telegram, Pizza, Topping, FilteredManager)
-from .admin import site, site2
+    Telegram, Pizza, Topping, FilteredManager, City, Restaurant, Worker)
+from .admin import site, site2, CityAdmin
 
 
 ERROR_MESSAGE = "Please enter the correct username and password \
@@ -4597,3 +4598,87 @@ class TestLabelVisibility(TestCase):
 
     def assert_fieldline_hidden(self, response):
         self.assertContains(response, '<div class="form-row hidden')
+
+
+@override_settings(PASSWORD_HASHERS=('django.contrib.auth.hashers.SHA1PasswordHasher',))
+class AdminViewOnSiteTest(TestCase):
+    urls = "admin_views.urls"
+    fixtures = ['admin-views-users.xml', 'admin-views-restaurants.xml']
+
+    def setUp(self):
+        self.client.login(username='super', password='secret')
+
+    def tearDown(self):
+        self.client.logout()
+
+    def test_validate(self):
+        "Ensure that the view_on_site value is either a boolean or a callable"
+        CityAdmin.view_on_site = True
+        CityAdmin.validate(City)
+        CityAdmin.view_on_site = False
+        CityAdmin.validate(City)
+        CityAdmin.view_on_site = lambda obj: obj.get_absolute_url()
+        CityAdmin.validate(City)
+        CityAdmin.view_on_site = []
+        with self.assertRaisesMessage(ImproperlyConfigured, 'CityAdmin.view_on_site is not a callable or a boolean value.'):
+            CityAdmin.validate(City)
+
+    def test_false(self):
+        "Ensure that the 'View on site' button is not displayed if view_on_site is False"
+        response = self.client.get('/test_admin/admin/admin_views/restaurant/1/')
+        content_type_pk = ContentType.objects.get_for_model(Restaurant).pk
+        self.assertNotContains(response,
+                               '"/test_admin/admin/r/%s/1/"' % content_type_pk,
+                               )
+
+    def test_true(self):
+        "Ensure that the default behaviour is followed if view_on_site is True"
+        response = self.client.get('/test_admin/admin/admin_views/city/1/')
+        content_type_pk = ContentType.objects.get_for_model(City).pk
+        self.assertContains(response,
+                            '"/test_admin/admin/r/%s/1/"' % content_type_pk,
+                            )
+
+    def test_callable(self):
+        "Ensure that the right link is displayed if view_on_site is a callable"
+        response = self.client.get('/test_admin/admin/admin_views/worker/1/')
+        worker = Worker.objects.get(pk=1)
+        self.assertContains(response,
+                            '"/worker/%s/%s/"' % (worker.surname, worker.name),
+                            )
+
+
+@override_settings(PASSWORD_HASHERS=('django.contrib.auth.hashers.SHA1PasswordHasher',))
+class InlineAdminViewOnSiteTest(TestCase):
+    urls = "admin_views.urls"
+    fixtures = ['admin-views-users.xml', 'admin-views-restaurants.xml']
+
+    def setUp(self):
+        self.client.login(username='super', password='secret')
+
+    def tearDown(self):
+        self.client.logout()
+
+    def test_false(self):
+        "Ensure that the 'View on site' button is not displayed if view_on_site is False"
+        response = self.client.get('/test_admin/admin/admin_views/state/1/')
+        content_type_pk = ContentType.objects.get_for_model(City).pk
+        self.assertNotContains(response,
+                               '/test_admin/admin/r/%s/1/' % content_type_pk,
+                               )
+
+    def test_true(self):
+        "Ensure that the 'View on site' button is displayed if view_on_site is True"
+        response = self.client.get('/test_admin/admin/admin_views/city/1/')
+        content_type_pk = ContentType.objects.get_for_model(Restaurant).pk
+        self.assertContains(response,
+                            '/test_admin/admin/r/%s/1/' % content_type_pk,
+                            )
+
+    def test_callable(self):
+        "Ensure that the right link is displayed if view_on_site is a callable"
+        response = self.client.get('/test_admin/admin/admin_views/restaurant/1/')
+        worker = Worker.objects.get(pk=1)
+        self.assertContains(response,
+                            '"/worker_inline/%s/%s/"' % (worker.surname, worker.name),
+                            )