Sync WidgetFilter with url (#491)

lumen/filters/base.py

@@ -63,9 +63,13 @@ class Filter(MultiTypeComponent):
 
     def __init__(self, **params):
         super().__init__(**params)
-        if state.config and state.config.sync_with_url and self.sync_with_url and pn.state.location:
+        if self._sync_with_url:
             pn.state.location.sync(self, {'value': self.field}, on_error=self._url_sync_error)
 
+    @property
+    def _sync_with_url(self) -> bool:
+        return bool(state.config and state.config.sync_with_url and self.sync_with_url and pn.state.location)
+
     @classproperty
     def _required_keys(cls) -> List[str | Tuple[str, ...]]:  # type: ignore
         return ['field'] if cls._requires_field else []
@@ -313,8 +317,11 @@ def __init__(self, **params):
         self.widget.name = self.label
         self.widget.visible = self.visible
         self.widget.disabled = self.disabled
+        val = self.value
         self.widget.link(self, bidirectional=True, value='value', visible='visible', disabled='disabled')
-        if self.default is not None:
+        if val is not None:
+            self.widget.value = val
+        elif self.default is not None:
             self.widget.value = self.default
 
     @classmethod

lumen/tests/sample_dashboard/sync_query_filters_default.yaml

@@ -0,0 +1,18 @@
+config:
+  sync_with_url: true
+sources:
+  test:
+    type: 'file'
+    files: ['../sources/test.csv']
+targets:
+  - title: "Test"
+    source: test
+    filters:
+      - type: widget
+        field: A
+      - type: widget
+        field: C
+        default: ['foo1']
+    views:
+      - table: test
+        type: test

lumen/tests/test_dashboard.py

@@ -90,6 +90,37 @@ def test_dashboard_with_url_sync_filters(set_root, document):
     pn.state.location.search = '?A=%5B0.3%2C+0.8%5D&C=%5B%22foo1%22%2C+%22foo2%22%2C+%22foo3%22%5D'
     assert f2.value == ['foo1', 'foo2', 'foo3']
 
+def test_dashboard_with_url_sync_filters_with_default(set_root, document):
+    root = pathlib.Path(__file__).parent / 'sample_dashboard'
+    set_root(str(root))
+    dashboard = Dashboard(str(root / 'sync_query_filters_default.yaml'))
+    dashboard._render_dashboard()
+    layout = dashboard.layouts[0]
+    f1, f2 = list(layout._pipelines.values())[0].filters
+    f1.value = (0.1, 0.7)
+    assert pn.state.location.search == '?C=%5B%27foo1%27%5D&A=%5B0.1%2C+0.7%5D'
+    pn.state.location.search = '?A=%5B0.3%2C+0.8%5D'
+    assert f1.value == (0.3, 0.8)
+    assert f2.value == ['foo1']
+    assert f1.widget.value == (0.3, 0.8)
+    assert f2.widget.value == ['foo1']
+    f2.value = ['foo1', 'foo2']
+    assert pn.state.location.search == '?A=%5B0.3%2C+0.8%5D&C=%5B%22foo1%22%2C+%22foo2%22%5D'
+    pn.state.location.search = '?A=%5B0.3%2C+0.8%5D&C=%5B%22foo1%22%2C+%22foo2%22%2C+%22foo3%22%5D'
+    assert f2.value == ['foo1', 'foo2', 'foo3']
+    assert f2.widget.value == ['foo1', 'foo2', 'foo3']
+
+def test_dashboard_with_url_sync_filters_with_overwritten_default(set_root, document):
+    root = pathlib.Path(__file__).parent / 'sample_dashboard'
+    set_root(str(root))
+    dashboard = Dashboard(str(root / 'sync_query_filters_default.yaml'))
+    dashboard._render_dashboard()
+    layout = dashboard.layouts[0]
+    f1, f2 = list(layout._pipelines.values())[0].filters
+    f1.value = (0.1, 0.7)
+    f2.value = []  # overwriting default with empty list
+    assert pn.state.location.search == '?C=%5B%5D&A=%5B0.1%2C+0.7%5D'
+    assert f2.widget.value == []
 
 @sql_available
 def test_dashboard_with_sql_source_and_transforms(set_root, document, mixed_df_object_type):

lumen/views/base.py

@@ -143,7 +143,7 @@ def __panel__(self) -> Viewable:
         return pn.panel(pn.bind(lambda e: self.panel, self.param.rerender))
 
     def _update_loading(self, event):
-        if self._panel is not None:
+        if hasattr(self._panel, 'loading'):
             with immediate_dispatch():
                 self._panel.loading = event.new