fix: add basic support for row grid "view" action links

still no actual "view row" support just yet, but subclass can
implement however they like..

src/wuttaweb/views/master.py

@@ -372,6 +372,20 @@ class MasterView(View):
        List of columns for the row grid.
 
        This is optional; see also :meth:`get_row_grid_columns()`.
+
+       This is optional; see also :meth:`get_row_grid_columns()`.
+
+    .. attribute:: rows_viewable
+
+       Boolean indicating whether the row model supports "viewing" -
+       i.e. it should have a "View" action in the row grid.
+
+       (For now) If you enable this, you must also override
+       :meth:`get_row_action_url_view()`.
+
+       .. note::
+          This eventually will cause there to be a ``row_view`` route
+          to be configured as well.
     """
 
     ##############################
@@ -409,6 +423,7 @@ class MasterView(View):
     rows_sort_defaults = None
     rows_paginated = True
     rows_paginate_on_backend = True
+    rows_viewable = False
 
     # current action
     listing = False
@@ -2414,6 +2429,16 @@ class MasterView(View):
         kwargs.setdefault('paginated', self.rows_paginated)
         kwargs.setdefault('paginate_on_backend', self.rows_paginate_on_backend)
 
+        if 'actions' not in kwargs:
+            actions = []
+
+            if self.rows_viewable:
+                actions.append(self.make_grid_action('view', icon='eye',
+                                                     url=self.get_row_action_url_view))
+
+            if actions:
+                kwargs['actions'] = actions
+
         grid = self.make_grid(**kwargs)
         self.configure_row_grid(grid)
         grid.load_settings()
@@ -2532,6 +2557,16 @@ class MasterView(View):
                 labels.update(cls.row_labels)
         return labels
 
+    def get_row_action_url_view(self, row, i):
+        """
+        Must return the "view" action url for the given row object.
+
+        Only relevant if :attr:`rows_viewable` is true.
+
+        There is no default logic; subclass must override if needed.
+        """
+        raise NotImplementedError
+
     ##############################
     # class methods
     ##############################

tests/views/test_master.py

@@ -1655,6 +1655,18 @@ class TestMasterView(WebTestCase):
                 self.assertIsNone(grid.model_class)
                 self.assertEqual(grid.data, [])
 
+            # view action
+            with patch.object(view, 'rows_viewable', new=True):
+                with patch.object(view, 'get_row_action_url_view', return_value='#'):
+                    grid = view.make_row_model_grid(person, data=[])
+                    self.assertEqual(len(grid.actions), 1)
+                    self.assertEqual(grid.actions[0].key, 'view')
+
+    def test_get_row_action_url_view(self):
+        view = self.make_view()
+        row = MagicMock()
+        self.assertRaises(NotImplementedError, view.get_row_action_url_view, row, 0)
+
     def test_get_rows_title(self):
         view = self.make_view()