webpack.config.js

const Path = require('path');
const webpack = require('webpack');
const rootDir = Path.resolve();

const config = [
    {
        name: 'js',
        entry: {
            'AddToCampaigns': rootDir + '/js-src/AddToCampaigns.js'
        },
        output: {
            path: rootDir,
            filename: 'javascript/[name].js',
            devtoolModuleFilenameTemplate: function(opts) {
                if(opts.resource.search('./js-src/')>=0 || opts.resource.search('./javascript/')>=0 || opts.resource.search('javascript/')==0) {
                    return '../../'+(opts.resourcePath)+'?'+(opts.hash);
                }
                
                return 'webpack:///'+(opts.resourcePath);
            },
            devtoolFallbackModuleFilenameTemplate: function(opts) {
                if(opts.resource.search('./js-src/')>=0 || opts.resource.search('./javascript/')>=0 || opts.resource.search('javascript/')==0) {
                    return '../../'+(opts.resourcePath)+'?'+(opts.hash);
                }
                
                return 'webpack:///'+(opts.resourcePath);
            }
        },
        devtool: 'nosources-source-map',
        module: {
            rules: [
                {
                    test: /\.(js|jsx)$/,
                    exclude: /node_modules/,
                    use: {
                        loader: 'babel-loader',
                        options: {
                            presets: [
                                [
                                    "@babel/env",
                                    {
                                        modules: false,
                                    }
                                ],
                                "@babel/react",
                            ],
                            comments: false,
                        },
                    }
                }
            ]
        },
        externals: {
            'apollo-client': 'ApolloClient',
            'bootstrap-collapse': 'BootstrapCollapse',
            classnames: 'classnames',
            'deep-freeze-strict': 'DeepFreezeStrict',
            'graphql-fragments': 'GraphQLFragments',
            'graphql-tag': 'GraphQLTag',
            history: 'history',
            'isomorphic-fetch': 'IsomorphicFetch',
            i18n: 'i18n',
            jquery: 'jQuery',
            merge: 'merge',
            'page.js': 'Page',
            'react-addons-test-utils': 'ReactAddonsTestUtils',
            'react-dom': 'ReactDom',
            poppers: 'Poppers',
            reactstrap: 'Reactstrap',
            'react-apollo': 'ReactApollo',
            'react-redux': 'ReactRedux',
            'react-router-redux': 'ReactRouterRedux',
            'react-router': 'ReactRouter',
            'react-select': 'ReactSelect',
            'react-addons-css-transition-group': 'ReactAddonsCssTransitionGroup',
            react: 'React',
            'redux-form': 'ReduxForm',
            'redux-thunk': 'ReduxThunk',
            redux: 'Redux',
            config: 'Config',
            qs: 'qs',
            moment: 'moment',
            modernizr: 'modernizr',
            'react-dnd': 'ReactDND',
            'react-dnd-html5-backend': 'ReactDNDHtml5Backend',
            validator: 'validator',
            'prop-types': 'PropTypes',

            // provided by silverstripe or modules
            'components/Accordion/Accordion': 'Accordion',
            'components/Accordion/AccordionBlock': 'AccordionBlock',
            'components/Breadcrumb/Breadcrumb': 'Breadcrumb',
            'components/FormAction/FormAction': 'FormAction',
            'components/FormBuilder/FormBuilder': 'FormBuilder',
            'components/FormBuilderModal/FormBuilderModal': 'FormBuilderModal',
            'components/FieldHolder/FieldHolder': 'FieldHolder',
            'components/GridField/GridField': 'GridField',
            'components/Toolbar/Toolbar': 'Toolbar',
            'components/LiteralField/LiteralField': 'LiteralField',
            'components/Preview/Preview': 'Preview',
            'components/ListGroup/ListGroup': 'ListGroup',
            'components/ListGroup/ListGroupItem': 'ListGroupItem',
            'components/Loading/Loading': 'Loading',
            'components/FormAlert/FormAlert': 'FormAlert',
            'components/Badge/Badge': 'Badge',
            'components/TreeDropdownField/TreeDropdownField': 'TreeDropdownField',
            'components/Focusedzone/Focusedzone': 'Focusedzone',
            'components/ViewModeToggle/ViewModeToggle': 'ViewModeToggle',
            'components/ResizeAware/ResizeAware': 'ResizeAware',
            'components/Tag/Tag': 'Tag',
            'components/Tag/TagList': 'TagList',
            'components/Tag/CompactTagList': 'CompactTagList',
            'components/Search/Search': 'Search',
            'components/Search/SearchToggle': 'SearchToggle',
            'containers/FormBuilderLoader/FormBuilderLoader': 'FormBuilderLoader',
            'containers/InsertMediaModal/InsertMediaModal': 'InsertMediaModal',
            'components/InsertEmbedModal/InsertEmbedModal': 'InsertEmbedModal',
            'containers/InsertLinkModal/InsertLinkModal': 'InsertLinkModal',
            'containers/InsertLinkModal/fileSchemaModalHandler': 'FileSchemaModalHandler',
            'state/breadcrumbs/BreadcrumbsActions': 'BreadcrumbsActions',
            'state/schema/SchemaActions': 'SchemaActions',
            'state/records/RecordsActions': 'RecordsActions',
            'state/records/RecordsActionTypes': 'RecordsActionTypes',
            'state/viewMode/ViewModeActions': 'ViewModeActions',
            'lib/DataFormat': 'DataFormat',
            'lib/Backend': 'Backend',
            'lib/getFormState': 'getFormState',
            'lib/ReactRouteRegister': 'ReactRouteRegister',
            'lib/ReducerRegister': 'ReducerRegister',
            'lib/SilverStripeComponent': 'SilverStripeComponent',
            'lib/formatWrittenNumber': 'formatWrittenNumber',
            'lib/Router': 'Router',
            'lib/schemaFieldValues': 'schemaFieldValues',
            'lib/Config': 'Config',
            'lib/Injector': 'Injector',
            'lib/reduxFieldReducer': 'reduxFieldReducer',
            'lib/TinyMCEActionRegistrar': 'TinyMCEActionRegistrar',
            'lib/ShortcodeSerialiser': 'ShortcodeSerialiser',
            'components/Loading/Loading': 'Loading',
        }
    },
];

// Use WEBPACK_CHILD=js or WEBPACK_CHILD=css env var to run a single config
module.exports = (process.env.WEBPACK_CHILD ? config.find((entry) => entry.name === process.env.WEBPACK_CHILD):module.exports = config);