Migrate Image/index.js to function component

src/components/Image/index.js

@@ -1,4 +1,4 @@
-import React from 'react';
+import React, {useEffect, useMemo} from 'react';
 import {Image as RNImage} from 'react-native';
 import {withOnyx} from 'react-native-onyx';
 import lodashGet from 'lodash/get';
@@ -7,76 +7,64 @@ import ONYXKEYS from '../../ONYXKEYS';
 import {defaultProps, imagePropTypes} from './imagePropTypes';
 import RESIZE_MODES from './resizeModes';
 
-class Image extends React.Component {
-    componentDidMount() {
-        this.configureOnLoad();
-    }
-
-    componentDidUpdate(prevProps) {
-        if (prevProps.source === this.props.source) {
-            return;
-        }
-        this.configureOnLoad();
-    }
-
+function Image(props) {
+    const {source: propsSource, isAuthTokenRequired, onLoad, session} = props;
     /**
      * Check if the image source is a URL - if so the `encryptedAuthToken` is appended
      * to the source.
-     * @returns {Object} - the configured image source
      */
-    getImageSource() {
-        const source = this.props.source;
-        let imageSource = source;
-        if (this.props.isAuthTokenRequired) {
+    const source = useMemo(() => {
+        if (isAuthTokenRequired) {
             // There is currently a `react-native-web` bug preventing the authToken being passed
             // in the headers of the image request so the authToken is added as a query param.
             // On native the authToken IS passed in the image request headers
-            const authToken = lodashGet(this.props, 'session.encryptedAuthToken', null);
-            imageSource = {uri: `${source.uri}?encryptedAuthToken=${encodeURIComponent(authToken)}`};
+            const authToken = lodashGet(session, 'encryptedAuthToken', null);
+            return {uri: `${propsSource.uri}?encryptedAuthToken=${encodeURIComponent(authToken)}`};
         }
-
-        return imageSource;
-    }
+        return propsSource;
+    }, [propsSource, isAuthTokenRequired, session]);
 
     /**
      * The natural image dimensions are retrieved using the updated source
      * and as a result the `onLoad` event needs to be manually invoked to return these dimensions
      */
-    configureOnLoad() {
+    useEffect(() => {
         // If an onLoad callback was specified then manually call it and pass
         // the natural image dimensions to match the native API
-        if (this.props.onLoad == null) {
+        if (onLoad == null) {
             return;
         }
-
-        const imageSource = this.getImageSource();
-        RNImage.getSize(imageSource.uri, (width, height) => {
-            this.props.onLoad({nativeEvent: {width, height}});
+        RNImage.getSize(source.uri, (width, height) => {
+            onLoad({nativeEvent: {width, height}});
         });
-    }
+    }, [onLoad, source]);
 
-    render() {
-        // Omit the props which the underlying RNImage won't use
-        const forwardedProps = _.omit(this.props, ['source', 'onLoad', 'session', 'isAuthTokenRequired']);
-        const source = this.getImageSource();
+    // Omit the props which the underlying RNImage won't use
+    const forwardedProps = _.omit(props, ['source', 'onLoad', 'session', 'isAuthTokenRequired']);
+
+    return (
+        <RNImage
+            // eslint-disable-next-line react/jsx-props-no-spreading
+            {...forwardedProps}
+            source={source}
+        />
+    );
+}
 
-        return (
-            <RNImage
-                // eslint-disable-next-line react/jsx-props-no-spreading
-                {...forwardedProps}
-                source={source}
-            />
-        );
-    }
+function imagePropsAreEqual(prevProps, nextProps) {
+    return prevProps.source === nextProps.source;
 }
 
 Image.propTypes = imagePropTypes;
 Image.defaultProps = defaultProps;
 
-const ImageWithOnyx = withOnyx({
-    session: {
-        key: ONYXKEYS.SESSION,
-    },
-})(Image);
+const ImageWithOnyx = React.memo(
+    withOnyx({
+        session: {
+            key: ONYXKEYS.SESSION,
+        },
+    })(Image),
+    imagePropsAreEqual,
+);
 ImageWithOnyx.resizeMode = RESIZE_MODES;
 export default ImageWithOnyx;