feat: add backend pagination support for grids

tests/grids/test_base.py

@@ -3,6 +3,7 @@
 from unittest import TestCase
 from unittest.mock import patch
 
+from paginate import Page
 from pyramid import testing
 
 from wuttjamaican.conf import WuttaConfig
@@ -168,6 +169,105 @@ class TestGrid(WebTestCase):
         size = grid.get_pagesize()
         self.assertEqual(size, 15)
 
+    ##############################
+    # configuration methods
+    ##############################
+
+    def test_load_settings(self):
+        grid = self.make_grid(key='foo', paginated=True, paginate_on_backend=True,
+                              pagesize=20, page=1)
+
+        # settings are loaded, applied, saved
+        self.assertEqual(grid.page, 1)
+        self.assertNotIn('grid.foo.page', self.request.session)
+        self.request.GET = {'pagesize': '10', 'page': '2'}
+        grid.load_settings()
+        self.assertEqual(grid.page, 2)
+        self.assertEqual(self.request.session['grid.foo.page'], 2)
+
+        # can skip the saving step
+        self.request.GET = {'pagesize': '10', 'page': '3'}
+        grid.load_settings(store=False)
+        self.assertEqual(grid.page, 3)
+        self.assertEqual(self.request.session['grid.foo.page'], 2)
+
+        # no error for non-paginated grid
+        grid = self.make_grid(key='foo', paginated=False)
+        grid.load_settings()
+        self.assertFalse(grid.paginated)
+
+    def test_request_has_settings(self):
+        grid = self.make_grid(key='foo')
+
+        self.assertFalse(grid.request_has_settings())
+
+        with patch.object(self.request, 'GET', new={'pagesize': '20'}):
+            self.assertTrue(grid.request_has_settings())
+
+        with patch.object(self.request, 'GET', new={'page': '1'}):
+            self.assertTrue(grid.request_has_settings())
+
+    def test_update_page_settings(self):
+        grid = self.make_grid(key='foo')
+
+        # settings are updated from session
+        settings = {'pagesize': 20, 'page': 1}
+        self.request.session['grid.foo.pagesize'] = 10
+        self.request.session['grid.foo.page'] = 2
+        grid.update_page_settings(settings)
+        self.assertEqual(settings['pagesize'], 10)
+        self.assertEqual(settings['page'], 2)
+
+        # settings are updated from request
+        self.request.GET = {'pagesize': '15', 'page': '4'}
+        grid.update_page_settings(settings)
+        self.assertEqual(settings['pagesize'], 15)
+        self.assertEqual(settings['page'], 4)
+
+    def test_persist_settings(self):
+        grid = self.make_grid(key='foo', paginated=True, paginate_on_backend=True)
+
+        # nb. no error if empty settings, but it saves null values
+        grid.persist_settings({})
+        self.assertIsNone(self.request.session['grid.foo.page'])
+
+        # provided values are saved
+        grid.persist_settings({'pagesize': 15, 'page': 3})
+        self.assertEqual(self.request.session['grid.foo.page'], 3)
+
+    ##############################
+    # data methods
+    ##############################
+
+    def test_get_visible_data(self):
+        data = [
+            {'foo': 1, 'bar': 1},
+            {'foo': 2, 'bar': 2},
+            {'foo': 3, 'bar': 3},
+            {'foo': 4, 'bar': 4},
+            {'foo': 5, 'bar': 5},
+            {'foo': 6, 'bar': 6},
+            {'foo': 7, 'bar': 7},
+            {'foo': 8, 'bar': 8},
+            {'foo': 9, 'bar': 9},
+        ]
+        grid = self.make_grid(data=data,
+                              columns=['foo', 'bar'],
+                              paginated=True, paginate_on_backend=True,
+                              pagesize=4, page=2)
+        visible = grid.get_visible_data()
+        self.assertEqual(len(visible), 4)
+        self.assertEqual(visible[0], {'foo': 5, 'bar': 5})
+
+    def test_paginate_data(self):
+        grid = self.make_grid()
+        pager = grid.paginate_data([])
+        self.assertIsInstance(pager, Page)
+
+    ##############################
+    # rendering methods
+    ##############################
+
     def test_render_vue_tag(self):
         grid = self.make_grid(columns=['foo', 'bar'])
         html = grid.render_vue_tag()
@@ -221,6 +321,28 @@ class TestGrid(WebTestCase):
         data = grid.get_vue_data()
         self.assertEqual(data, [{'foo': 'blah blah', '_action_url_view': '/blarg'}])
 
+    def test_get_vue_pager_stats(self):
+        data = [
+            {'foo': 1, 'bar': 1},
+            {'foo': 2, 'bar': 2},
+            {'foo': 3, 'bar': 3},
+            {'foo': 4, 'bar': 4},
+            {'foo': 5, 'bar': 5},
+            {'foo': 6, 'bar': 6},
+            {'foo': 7, 'bar': 7},
+            {'foo': 8, 'bar': 8},
+            {'foo': 9, 'bar': 9},
+        ]
+
+        grid = self.make_grid(columns=['foo', 'bar'], pagesize=4, page=2)
+        grid.pager = grid.paginate_data(data)
+        stats = grid.get_vue_pager_stats()
+        self.assertEqual(stats['item_count'], 9)
+        self.assertEqual(stats['items_per_page'], 4)
+        self.assertEqual(stats['page'], 2)
+        self.assertEqual(stats['first_item'], 5)
+        self.assertEqual(stats['last_item'], 8)
+
 
 class TestGridAction(TestCase):