[feat] Feature flag system via config (#5960)

* [feat] Feature flag system via config

Adding a feature flag system that is driven by superset_config.py. This change includes:
- Server side changes to specify a dedicated FEATURE_FLAG dictionary for listing feature flags. E.g.
```
FEATURE_FLAGS = { 'SCOPED_FILTER': true }
```
- Pass the new feature flags to client via bootstrap-data
- Client side changes to inject feature flags into the redux state tree for dashboard, explore view and SqlLab
- Client side refactor/clean up so the feature flags can be properly tested. Also avoid modifying incoming bootstrap data when creating initial state for the redux state tree
- Re-enable tests that were previously disabled for ExploreViewContainer

* Fix lint errors.

* Remove the partial attempt to get reference to src working in tests (so we don't have to write ../../../src and such in tests). This will in a separate PR.

superset/assets/spec/javascripts/explore/components/ExploreViewContainer_spec.js

@@ -1,38 +0,0 @@
-// this test must be commented out because ChartContainer is now importing files
-// from visualizations/*.js which are also importing css files which breaks in the testing env.
-
-// import React from 'react';
-// import { expect } from 'chai';
-// // import { shallow } from 'enzyme';
-
-// import ExploreViewContainer
-//   from '../../../../src/explore/components/ExploreViewContainer';
-// import QueryAndSaveBtns
-//   from '../../../../src/explore/components/QueryAndSaveBtns';
-// import ControlPanelsContainer
-//   from '../../../../src/explore/components/ControlPanelsContainer';
-// import ChartContainer
-//   from '../../../../src/explore/components/ChartContainer';
-
-// describe('ExploreViewContainer', () => {
-//   it('renders', () => {
-//     expect(
-//       React.isValidElement(<ExploreViewContainer />)
-//     ).to.equal(true);
-//   });
-
-//   it('renders QueryAndSaveButtons', () => {
-//     const wrapper = shallow(<ExploreViewContainer />);
-//     expect(wrapper.find(QueryAndSaveBtns)).to.have.length(1);
-//   });
-
-//   it('renders ControlPanelsContainer', () => {
-//     const wrapper = shallow(<ExploreViewContainer />);
-//     expect(wrapper.find(ControlPanelsContainer)).to.have.length(1);
-//   });
-
-//   it('renders ChartContainer', () => {
-//     const wrapper = shallow(<ExploreViewContainer />);
-//     expect(wrapper.find(ChartContainer)).to.have.length(1);
-//   });
-// });

superset/assets/spec/javascripts/explore/components/ExploreViewContainer_spec.jsx

@@ -0,0 +1,69 @@
+import React from 'react';
+import configureStore from 'redux-mock-store';
+import thunk from 'redux-thunk';
+import { expect } from 'chai';
+import { shallow } from 'enzyme';
+
+import getInitialState from '../../../../src/explore/reducers/getInitialState';
+import ExploreViewContainer
+  from '../../../../src/explore/components/ExploreViewContainer';
+import QueryAndSaveBtns
+  from '../../../../src/explore/components/QueryAndSaveBtns';
+import ControlPanelsContainer
+  from '../../../../src/explore/components/ControlPanelsContainer';
+import ChartContainer
+  from '../../../../src/explore/components/ExploreChartPanel';
+
+describe('ExploreViewContainer', () => {
+  const middlewares = [thunk];
+  const mockStore = configureStore(middlewares);
+  let store;
+  let wrapper;
+
+  before(() => {
+    const bootstrapData = {
+      common: {
+        feature_flags: {
+          FOO_BAR: true,
+        },
+        conf: {},
+      },
+      datasource: {
+        columns: [],
+      },
+      form_data: {
+        datasource: {},
+      },
+    };
+    store = mockStore(getInitialState(bootstrapData), {});
+  });
+
+  beforeEach(() => {
+    wrapper = shallow(<ExploreViewContainer />, {
+      context: { store },
+      disableLifecycleMethods: true,
+    });
+  });
+
+  it('should set feature flags', () => {
+    expect(wrapper.prop('isFeatureEnabled')('FOO_BAR')).to.equal(true);
+  });
+
+  it('renders', () => {
+    expect(
+      React.isValidElement(<ExploreViewContainer />),
+    ).to.equal(true);
+  });
+
+  it('renders QueryAndSaveButtons', () => {
+    expect(wrapper.dive().find(QueryAndSaveBtns)).to.have.length(1);
+  });
+
+  it('renders ControlPanelsContainer', () => {
+    expect(wrapper.dive().find(ControlPanelsContainer)).to.have.length(1);
+  });
+
+  it('renders ChartContainer', () => {
+    expect(wrapper.dive().find(ChartContainer)).to.have.length(1);
+  });
+});