rollup-plugin-consts/dist/rollup-plugin-consts.cjs

Import build time constants with Rollup

'use strict';

/**
 * Copyright 2019 Google Inc. All Rights Reserved.
 * 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.
 */
const moduleStart = 'consts:';

/**
 * Import build time constants with Rollup.
 *
 * @param {{ [name: string]: unknown }} consts Replacement values in the form of string: replacement
 * @returns {import('rollup').Plugin}
 *
 * @example
 * import environment from 'consts:environment';
 *
 * if (environment === 'production') {
 *     // Production only code ...
 * } else {
 *     // Development only code ...
 * }
 */
function constsPlugin(consts) {
    return {
        name: 'consts-plugin',
        resolveId(id) {
            if (!id.startsWith(moduleStart)) return;
            return id;
        },
        load(id) {
            if (!id.startsWith(moduleStart)) return;
            const key = id.slice(moduleStart.length);

            if (!(key in consts)) {
                this.error(`Cannot find const: ${key}`);
                return;
            }

            return `export default ${JSON.stringify(consts[key])}`;
        },
    };
}

module.exports = constsPlugin;
module.exports.consts = constsPlugin;