Only show "View live" buttons if pages are accessible (#3983)

"View live" buttons in flash messages are now only displayed if the page
has a live URL. Editing pages that do not have a URL will no longer
produce broken buttons.

Fixes #3982

wagtail/wagtailadmin/messages.py

@@ -62,4 +62,6 @@ def validation_error(request, message, form, buttons=None):
 
 
 def button(url, text, new_window=False):
+    if url is None:
+        raise ValueError("Button URLs must not be None")
     return url, text, new_window

wagtail/wagtailadmin/tests/test_pages_views.py

@@ -3837,6 +3837,120 @@ class TestIssue2492(TestCase, WagtailTestUtils):
             break
 
 
+class TestIssue3982(TestCase, WagtailTestUtils):
+    """
+    Pages that are not associated with a site, and thus do not have a live URL,
+    should not display a "View live" link in the flash message after being
+    edited.
+    """
+
+    def setUp(self):
+        super().setUp()
+        self.login()
+
+    def _create_page(self, parent):
+        response = self.client.post(
+            reverse('wagtailadmin_pages:add', args=('tests', 'simplepage', parent.pk)),
+            {'title': "Hello, world!", 'content': "Some content", 'slug': 'hello-world', 'action-publish': "publish"},
+            follow=True)
+        self.assertRedirects(response, reverse('wagtailadmin_explore', args=(parent.pk,)))
+        page = SimplePage.objects.get()
+        self.assertTrue(page.live)
+        return response, page
+
+    def test_create_accessible(self):
+        """
+        Create a page under the site root, check the flash message has a valid
+        "View live" button.
+        """
+        response, page = self._create_page(Page.objects.get(pk=2))
+        self.assertIsNotNone(page.url)
+        self.assertTrue(any(
+            'View live' in message.message and page.url in message.message
+            for message in response.context['messages']))
+
+    def test_create_inaccessible(self):
+        """
+        Create a page outside of the site root, check the flash message does
+        not have a "View live" button.
+        """
+        response, page = self._create_page(Page.objects.get(pk=1))
+        self.assertIsNone(page.url)
+        self.assertFalse(any(
+            'View live' in message.message
+            for message in response.context['messages']))
+
+    def _edit_page(self, parent):
+        page = parent.add_child(instance=SimplePage(title='Hello, world!', content='Some content'))
+        response = self.client.post(
+            reverse('wagtailadmin_pages:edit', args=(page.pk,)),
+            {'title': "Hello, world!", 'content': "Some content", 'slug': 'hello-world', 'action-publish': "publish"},
+            follow=True)
+        self.assertRedirects(response, reverse('wagtailadmin_explore', args=(parent.pk,)))
+        page = SimplePage.objects.get(pk=page.pk)
+        self.assertTrue(page.live)
+        return response, page
+
+    def test_edit_accessible(self):
+        """
+        Edit a page under the site root, check the flash message has a valid
+        "View live" button.
+        """
+        response, page = self._edit_page(Page.objects.get(pk=2))
+        self.assertIsNotNone(page.url)
+        self.assertTrue(any(
+            'View live' in message.message and page.url in message.message
+            for message in response.context['messages']))
+
+    def test_edit_inaccessible(self):
+        """
+        Edit a page outside of the site root, check the flash message does
+        not have a "View live" button.
+        """
+        response, page = self._edit_page(Page.objects.get(pk=1))
+        self.assertIsNone(page.url)
+        self.assertFalse(any(
+            'View live' in message.message
+            for message in response.context['messages']))
+
+    def _approve_page(self, parent):
+        response = self.client.post(
+            reverse('wagtailadmin_pages:add', args=('tests', 'simplepage', parent.pk)),
+            {'title': "Hello, world!", 'content': "Some content", 'slug': 'hello-world', 'action-submit': "submit"},
+            follow=True)
+        self.assertRedirects(response, reverse('wagtailadmin_explore', args=(parent.pk,)))
+        page = SimplePage.objects.get()
+        self.assertFalse(page.live)
+        revision = PageRevision.objects.get(page=page)
+        response = self.client.post(reverse('wagtailadmin_pages:approve_moderation', args=(revision.pk,)), follow=True)
+        page = SimplePage.objects.get()
+        self.assertTrue(page.live)
+        self.assertRedirects(response, reverse('wagtailadmin_home'))
+        return response, page
+
+    def test_approve_accessible(self):
+        """
+        Edit a page under the site root, check the flash message has a valid
+        "View live" button.
+        """
+        response, page = self._approve_page(Page.objects.get(pk=2))
+        self.assertIsNotNone(page.url)
+        self.assertTrue(any(
+            'View live' in message.message and page.url in message.message
+            for message in response.context['messages']))
+
+    def test_approve_inaccessible(self):
+        """
+        Edit a page outside of the site root, check the flash message does
+        not have a "View live" button.
+        """
+        response, page = self._approve_page(Page.objects.get(pk=1))
+        self.assertIsNone(page.url)
+        self.assertFalse(any(
+            'View live' in message.message
+            for message in response.context['messages']))
+
+
 class TestInlinePanelMedia(TestCase, WagtailTestUtils):
     """
     Test that form media required by InlinePanels is correctly pulled in to the edit page

wagtail/wagtailadmin/views/pages.py

@@ -222,10 +222,11 @@ def create(request, content_type_app_name, content_type_model_name, parent_page_
                         messages.button(reverse('wagtailadmin_pages:edit', args=(page.id,)), _('Edit'))
                     ])
                 else:
-                    messages.success(request, _("Page '{0}' created and published.").format(page.get_admin_display_title()), buttons=[
-                        messages.button(page.url, _('View live'), new_window=True),
-                        messages.button(reverse('wagtailadmin_pages:edit', args=(page.id,)), _('Edit'))
-                    ])
+                    buttons = []
+                    if page.url is not None:
+                        buttons.append(messages.button(page.url, _('View live'), new_window=True))
+                    buttons.append(messages.button(reverse('wagtailadmin_pages:edit', args=(page.id,)), _('Edit')))
+                    messages.success(request, _("Page '{0}' created and published.").format(page.get_admin_display_title()), buttons=buttons)
             elif is_submitting:
                 messages.success(
                     request,
@@ -386,17 +387,11 @@ def edit(request, page_id):
                             page.get_admin_display_title()
                         )
 
-                    messages.success(request, message, buttons=[
-                        messages.button(
-                            page.url,
-                            _('View live'),
-                            new_window=True
-                        ),
-                        messages.button(
-                            reverse('wagtailadmin_pages:edit', args=(page_id,)),
-                            _('Edit')
-                        )
-                    ])
+                    buttons = []
+                    if page.url is not None:
+                        buttons.append(messages.button(page.url, _('View live'), new_window=True))
+                    buttons.append(messages.button(reverse('wagtailadmin_pages:edit', args=(page_id,)), _('Edit')))
+                    messages.success(request, message, buttons=buttons)
 
             elif is_submitting:
 
@@ -905,10 +900,14 @@ def approve_moderation(request, revision_id):
 
     if request.method == 'POST':
         revision.approve_moderation()
-        messages.success(request, _("Page '{0}' published.").format(revision.page.get_admin_display_title()), buttons=[
-            messages.button(revision.page.url, _('View live'), new_window=True),
-            messages.button(reverse('wagtailadmin_pages:edit', args=(revision.page.id,)), _('Edit'))
-        ])
+
+        message = _("Page '{0}' published.").format(revision.page.get_admin_display_title())
+        buttons = []
+        if revision.page.url is not None:
+            buttons.append(messages.button(revision.page.url, _('View live'), new_window=True))
+        buttons.append(messages.button(reverse('wagtailadmin_pages:edit', args=(revision.page.id,)), _('Edit')))
+        messages.success(request, message, buttons=buttons)
+
         if not send_notification(revision.id, 'approved', request.user.pk):
             messages.error(request, _("Failed to send approval notifications"))