replace class components (HOCs) with React Hooks

interface/package.json

@@ -3,13 +3,13 @@
   "version": "0.1.0",
   "private": true,
   "dependencies": {
-    "@material-ui/core": "^4.11.4",
+    "@material-ui/core": "^4.12.3",
     "@material-ui/icons": "^4.11.2",
     "@msgpack/msgpack": "^2.7.0",
-    "@types/lodash": "^4.14.168",
-    "@types/node": "^15.0.1",
-    "@types/react": "^17.0.4",
-    "@types/react-dom": "^17.0.3",
+    "@types/lodash": "^4.14.172",
+    "@types/node": "^12.20.20",
+    "@types/react": "^17.0.19",
+    "@types/react-dom": "^17.0.9",
     "@types/react-material-ui-form-validator": "^2.1.0",
     "@types/react-router": "^5.1.13",
     "@types/react-router-dom": "^5.1.7",
@@ -30,7 +30,7 @@
     "react-router-dom": "^5.2.0",
     "react-scripts": "4.0.3",
     "sockette": "^2.0.6",
-    "typescript": "4.2.4",
+    "typescript": "4.3.5",
     "zlib": "^1.0.5"
   },
   "scripts": {

interface/src/authentication/UnauthenticatedRoute.tsx

@@ -22,25 +22,13 @@ interface UnauthenticatedRouteProps
     | React.ComponentType<any>;
 }
 
-type RenderComponent = (props: RouteComponentProps<any>) => React.ReactNode;
-
 class UnauthenticatedRoute extends Route<UnauthenticatedRouteProps> {
   public render() {
-    const {
-      authenticationContext,
-      component: Component,
-      features,
-      ...rest
-    } = this.props;
-    const renderComponent: RenderComponent = (props) => {
-      if (authenticationContext.me) {
-        return <Redirect to={Authentication.fetchLoginRedirect(features)} />;
-      }
-      if (Component) {
-        return <Component {...props} />;
-      }
-    };
-    return <Route {...rest} render={renderComponent} />;
+    const { authenticationContext, features, ...rest } = this.props;
+    if (authenticationContext.me) {
+      return <Redirect to={Authentication.fetchLoginRedirect(features)} />;
+    }
+    return <Route {...rest} />;
   }
 }
 

interface/src/components/FormLoader.tsx

@@ -0,0 +1,56 @@
+import { FC } from 'react';
+
+import { makeStyles, Theme, createStyles } from '@material-ui/core/styles';
+import { Button, LinearProgress, Typography } from '@material-ui/core';
+
+const useStyles = makeStyles((theme: Theme) =>
+  createStyles({
+    loadingSettings: {
+      margin: theme.spacing(0.5)
+    },
+    loadingSettingsDetails: {
+      margin: theme.spacing(4),
+      textAlign: 'center'
+    },
+    button: {
+      marginRight: theme.spacing(2),
+      marginTop: theme.spacing(2)
+    }
+  })
+);
+
+interface FormLoaderProps {
+  errorMessage?: string;
+  loadData: () => void;
+}
+
+const FormLoader: FC<FormLoaderProps> = ({ errorMessage, loadData }) => {
+  const classes = useStyles();
+  if (errorMessage) {
+    return (
+      <div className={classes.loadingSettings}>
+        <Typography variant="h6" className={classes.loadingSettingsDetails}>
+          {errorMessage}
+        </Typography>
+        <Button
+          variant="contained"
+          color="secondary"
+          className={classes.button}
+          onClick={loadData}
+        >
+          Retry
+        </Button>
+      </div>
+    );
+  }
+  return (
+    <div className={classes.loadingSettings}>
+      <LinearProgress className={classes.loadingSettingsDetails} />
+      <Typography variant="h6" className={classes.loadingSettingsDetails}>
+        Loading&hellip;
+      </Typography>
+    </div>
+  );
+};
+
+export default FormLoader;

interface/src/components/index.ts

@@ -5,6 +5,7 @@ export { default as HighlightAvatar } from './HighlightAvatar';
 export { default as MenuAppBar } from './MenuAppBar';
 export { default as PasswordValidator } from './PasswordValidator';
 export { default as RestFormLoader } from './RestFormLoader';
+export { default as FormLoader } from './FormLoader';
 export { default as SectionContent } from './SectionContent';
 export { default as WebSocketFormLoader } from './WebSocketFormLoader';
 export { default as ErrorButton } from './ErrorButton';

interface/src/features/FeaturesWrapper.tsx

@@ -1,58 +1,31 @@
-import { Component } from 'react';
+import { FC } from 'react';
 
-import { Features } from './types';
-import { FeaturesContext } from './FeaturesContext';
 import FullScreenLoading from '../components/FullScreenLoading';
 import ApplicationError from '../components/ApplicationError';
 import { FEATURES_ENDPOINT } from '../api';
+import { useRest } from '../hooks';
 
-interface FeaturesWrapperState {
-  features?: Features;
-  error?: string;
-}
+import { Features } from './types';
+import { FeaturesContext } from './FeaturesContext';
 
-class FeaturesWrapper extends Component<{}, FeaturesWrapperState> {
-  state: FeaturesWrapperState = {};
+const FeaturesWrapper: FC = ({ children }) => {
+  const { data: features, errorMessage: error } = useRest<Features>({
+    endpoint: FEATURES_ENDPOINT
+  });
 
-  componentDidMount() {
-    this.fetchFeaturesDetails();
+  if (features) {
+    return (
+      <FeaturesContext.Provider value={{ features }}>
+        {children}
+      </FeaturesContext.Provider>
+    );
   }
 
-  fetchFeaturesDetails = () => {
-    fetch(FEATURES_ENDPOINT)
-      .then((response) => {
-        if (response.status === 200) {
-          return response.json();
-        } else {
-          throw Error('Unexpected status code: ' + response.status);
-        }
-      })
-      .then((features) => {
-        this.setState({ features });
-      })
-      .catch((error) => {
-        this.setState({ error: error.message });
-      });
-  };
-
-  render() {
-    const { features, error } = this.state;
-    if (features) {
-      return (
-        <FeaturesContext.Provider
-          value={{
-            features
-          }}
-        >
-          {this.props.children}
-        </FeaturesContext.Provider>
-      );
-    }
-    if (error) {
-      return <ApplicationError error={error} />;
-    }
-    return <FullScreenLoading />;
+  if (error) {
+    return <ApplicationError error={error} />;
   }
-}
+
+  return <FullScreenLoading />;
+};
 
 export default FeaturesWrapper;

interface/src/hooks/index.ts

@@ -0,0 +1,2 @@
+export { default as useRest } from './useRest';
+export { default as useAuthorizedRest } from './useAuthorizedRest';

interface/src/hooks/useAuthorizedRest.ts

@@ -0,0 +1,12 @@
+import { redirectingAuthorizedFetch } from '../authentication';
+import useRest, { RestRequestOptions } from './useRest';
+
+const useAuthorizedRest = <D>({
+  endpoint
+}: Omit<RestRequestOptions, 'fetchFunction'>) =>
+  useRest<D>({
+    endpoint,
+    fetchFunction: redirectingAuthorizedFetch
+  });
+
+export default useAuthorizedRest;

interface/src/hooks/useRest.ts

@@ -0,0 +1,79 @@
+import { useCallback, useEffect, useState } from 'react';
+import { useSnackbar } from 'notistack';
+
+export interface RestRequestOptions {
+  endpoint: string;
+  fetchFunction?: typeof fetch;
+}
+
+const useRest = <D>({
+  endpoint,
+  fetchFunction = fetch
+}: RestRequestOptions) => {
+  const { enqueueSnackbar } = useSnackbar();
+
+  const [saving, setSaving] = useState<boolean>(false);
+  const [data, setData] = useState<D>();
+  const [errorMessage, setErrorMessage] = useState<string>();
+
+  const handleError = useCallback(
+    (error: any) => {
+      const errorMessage = error.message || 'Unknown error';
+      enqueueSnackbar('Problem fetching: ' + errorMessage, {
+        variant: 'error'
+      });
+      setErrorMessage(errorMessage);
+    },
+    [enqueueSnackbar]
+  );
+
+  const loadData = useCallback(async () => {
+    setData(undefined);
+    setErrorMessage(undefined);
+    try {
+      const response = await fetchFunction(endpoint);
+      if (response.status !== 200) {
+        throw Error('Invalid status code: ' + response.status);
+      }
+      setData(await response.json());
+    } catch (error) {
+      handleError(error);
+    }
+  }, [handleError, fetchFunction, endpoint]);
+
+  const save = useCallback(
+    async (data: D) => {
+      setSaving(true);
+      setErrorMessage(undefined);
+      try {
+        const response = await fetchFunction(endpoint, {
+          method: 'POST',
+          body: JSON.stringify(data),
+          headers: {
+            'Content-Type': 'application/json'
+          }
+        });
+        if (response.status !== 200) {
+          throw Error('Invalid status code: ' + response.status);
+        }
+        enqueueSnackbar('Update successful.', { variant: 'success' });
+        setData(await response.json());
+      } catch (error) {
+        handleError(error);
+      } finally {
+        setSaving(false);
+      }
+    },
+    [enqueueSnackbar, handleError, fetchFunction, endpoint]
+  );
+
+  const saveData = () => data && save(data);
+
+  useEffect(() => {
+    loadData();
+  }, [loadData]);
+
+  return { loadData, saveData, saving, setData, data, errorMessage } as const;
+};
+
+export default useRest;

interface/src/utils/binding.ts

@@ -0,0 +1,33 @@
+type UpdateEntity<S> = (state: (prevState: Readonly<S>) => S) => void;
+
+export const extractEventValue = (
+  event: React.ChangeEvent<HTMLInputElement>
+) => {
+  switch (event.target.type) {
+    case 'number':
+      return event.target.valueAsNumber;
+    case 'checkbox':
+      return event.target.checked;
+    default:
+      return event.target.value;
+  }
+};
+
+export const updateValue = <S>(updateEntity: UpdateEntity<S>) => (
+  event: React.ChangeEvent<HTMLInputElement>
+) => {
+  updateEntity((prevState) => ({
+    ...prevState,
+    [event.target.name]: extractEventValue(event)
+  }));
+};
+
+export const updateBooleanValue = <S>(updateEntity: UpdateEntity<S>) => (
+  name: string,
+  value?: boolean
+) => {
+  updateEntity((prevState) => ({
+    ...prevState,
+    [name]: value
+  }));
+};

interface/src/utils/index.ts

@@ -0,0 +1 @@
+export * from './binding';