Add custom hook to refetch data when websocket reconnects

Add a custom React hook that can be used to perform an action when the websocket is reconnected (but not on initial connection). This is useful in our containers so we can avoid refetching when the websocket disconnects (default behaviour if we use `webSocketConnected` as a dependency for `useEffect`). This avoid unnecessary and unwanted requests while keeping the container logic relatively simple. In future with `react-query` or similar libraries we can easily change the central `useWebSocketReconnected` hook as needed without having to update each container. Continue refactoring containers to be functional components, using the new hook as appropriate.
grofers · May 4, 2021 · ea51272 · ea51272
1 parent 0128c26
commit ea51272
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Showing 26 changed files with 1,199 additions and 1,094 deletions.
diff --git a/package-lock.json b/package-lock.json
diff --git a/package.json b/package.json
@@ -74,6 +74,7 @@
     "@storybook/theming": "^6.2.1",
     "@svgr/webpack": "^5.5.0",
     "@testing-library/react": "^11.2.2",
+    "@testing-library/react-hooks": "5.1.2",
     "babel-eslint": "^10.1.0",
     "babel-loader": "^8.2.2",
     "babel-plugin-react-intl": "^8.2.18",

diff --git a/packages/utils/src/utils/hooks.js b/packages/utils/src/utils/hooks.js
@@ -0,0 +1,34 @@
+/*
+Copyright 2021 The Tekton Authors
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { useEffect, useRef } from 'react';
+
+export function usePrevious(value) {
+  const ref = useRef();
+
+  useEffect(() => {
+    ref.current = value;
+  }, [value]);
+
+  return ref.current;
+}
+
+export function useWebSocketReconnected(callback, webSocketConnected) {
+  const prevWebSocketConnected = usePrevious(webSocketConnected);
+
+  useEffect(() => {
+    if (prevWebSocketConnected === false && webSocketConnected) {
+      callback();
+    }
+  }, [prevWebSocketConnected, webSocketConnected]);
+}
diff --git a/packages/utils/src/utils/hooks.test.js b/packages/utils/src/utils/hooks.test.js
@@ -0,0 +1,52 @@
+/*
+Copyright 2021 The Tekton Authors
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { renderHook } from '@testing-library/react-hooks';
+
+import { usePrevious, useWebSocketReconnected } from './hooks';
+
+describe('hooks', () => {
+  it('usePrevious', () => {
+    let initialValue = 0;
+    const { result, rerender } = renderHook(() => usePrevious(initialValue));
+
+    initialValue = 10;
+    rerender();
+    expect(result.current).toEqual(0);
+
+    initialValue = 1;
+    rerender();
+    expect(result.current).toEqual(10);
+  });
+
+  it('useWebSocketReconnected', () => {
+    const callback = jest.fn();
+    let webSocketConnected;
+
+    const { rerender } = renderHook(() =>
+      useWebSocketReconnected(callback, webSocketConnected)
+    );
+    expect(callback).not.toHaveBeenCalled();
+    webSocketConnected = true;
+    rerender();
+    expect(callback).not.toHaveBeenCalled();
+    webSocketConnected = false;
+    rerender();
+    expect(callback).not.toHaveBeenCalled();
+    // callback is only called if websocket was previously disconnected
+    // i.e. doesn't get called on initial connection
+    webSocketConnected = true;
+    rerender();
+    expect(callback).toHaveBeenCalled();
+  });
+});
diff --git a/packages/utils/src/utils/index.js b/packages/utils/src/utils/index.js
@@ -1,5 +1,5 @@
 /*
-Copyright 2019-2020 The Tekton Authors
+Copyright 2019-2021 The Tekton Authors
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
@@ -16,6 +16,7 @@ import { getStatus } from './status';
 
 export { default as buildGraphData } from './buildGraphData';
 export * from './constants';
+export * from './hooks';
 export { paths, urls } from './router';
 export { getStatus } from './status';
 

diff --git a/src/containers/ClusterInterceptors/ClusterInterceptors.js b/src/containers/ClusterInterceptors/ClusterInterceptors.js
@@ -15,7 +15,12 @@ import React, { useEffect } from 'react';
 import { Link } from 'react-router-dom';
 import { connect } from 'react-redux';
 import { injectIntl } from 'react-intl';
-import { getFilters, getTitle, urls } from '@tektoncd/dashboard-utils';
+import {
+  getFilters,
+  getTitle,
+  urls,
+  useWebSocketReconnected
+} from '@tektoncd/dashboard-utils';
 import { FormattedDate, Table } from '@tektoncd/dashboard-components';
 
 import { ListPageLayout } from '..';
@@ -42,9 +47,15 @@ function ClusterInterceptors(props) {
     document.title = getTitle({ page: 'ClusterInterceptors' });
   }, []);
 
-  useEffect(() => {
+  function fetchData() {
     fetchClusterInterceptors({ filters });
-  }, [JSON.stringify(filters), webSocketConnected]);
+  }
+
+  useEffect(() => {
+    fetchData();
+  }, [JSON.stringify(filters)]);
+
+  useWebSocketReconnected(fetchData, webSocketConnected);
 
   function getError() {
     if (error) {

diff --git a/src/containers/ClusterTasks/ClusterTasks.js b/src/containers/ClusterTasks/ClusterTasks.js
@@ -26,7 +26,12 @@ import {
   TrashCan16 as DeleteIcon,
   Playlist16 as RunsIcon
 } from '@carbon/icons-react';
-import { getFilters, getTitle, urls } from '@tektoncd/dashboard-utils';
+import {
+  getFilters,
+  getTitle,
+  urls,
+  useWebSocketReconnected
+} from '@tektoncd/dashboard-utils';
 
 import { ListPageLayout } from '..';
 import { fetchClusterTasks as fetchClusterTasksActionCreator } from '../../actions/tasks';
@@ -62,9 +67,15 @@ function ClusterTasksContainer(props) {
     document.title = getTitle({ page: 'ClusterTasks' });
   }, []);
 
-  useEffect(() => {
+  function fetchData() {
     fetchClusterTasks({ filters });
-  }, [JSON.stringify(filters), webSocketConnected]);
+  }
+
+  useEffect(() => {
+    fetchData();
+  }, [JSON.stringify(filters)]);
+
+  useWebSocketReconnected(fetchData, webSocketConnected);
 
   function getError() {
     if (error) {