@dvhb/webpack/scripts/config.js

'use strict';

/* eslint-disable no-console */

const fs = require('fs');
const path = require('path');
const findup = require('findup');
const semverUtils = require('semver-utils');
const prettyjson = require('prettyjson');
const merge = require('lodash/merge');
const isFinite = require('lodash/isFinite');
const isUndefined = require('lodash/isUndefined');
const utils = require('./utils/utils');
const consts = require('./consts');
const DvhbWebpackError = require('./utils/error');

const CONFIG_FILENAME = 'dvhb.config.js';
const DEFAULT_CONFIG = {
    title: 'Dvhb Webpack Starter kit',
    sourceDir: 'src',
    assetsDir: null,
    distDir: 'dist',
    viewsDir: 'src/views',
    template: 'src/index.html',
    serverHost: 'localhost',
    serverPort: 3000,
    verbose: false,
    extendWebpackConfig: null
};
const DEPENDENCIES = [
    {
        package: 'babel-core',
        name: 'Babel',
        from: 6,
        to: 6,
    },
    {
        package: 'webpack',
        name: 'Webpack',
        from: 1,
        to: 2,
    },
];

/**
 * Read, parse and validate config file or passed config.
 *
 * @param {object} [options] CLI options (e.g. {verbose: true} or {config: 'filename'}) or all config options.
 * @returns {object}
 */
function getConfig(options) {
    options = options || {};

    let configFilepath;
    let config;

    // Read config options from a file
    configFilepath = findConfig(options.config);
    config = require(configFilepath);

    validateConfig(config);

    const configDir = configFilepath ? path.dirname(configFilepath) : process.cwd();

    validateDependencies(configDir);

    let assetsDir = null;
    if (typeof config.assetsDir === 'string') {
        assetsDir = path.resolve(configDir, config.assetsDir);
        if (!utils.isDirectoryExists(assetsDir)) {
            throw new DvhbWebpackError('DvhbWebpack: "assetsDir" directory not found: ' + assetsDir);
        }
    }
    if (Array.isArray(config.assetsDir)) {
        assetsDir = [];
        config.assetsDir.forEach(function (dir) {
            assetsDir.push(path.resolve(configDir, dir));
        });
    }

    config = merge({}, DEFAULT_CONFIG, config);
    config = merge({}, config, {
        env: options.env || 'development',
        verbose: !!options.verbose,
        sourceDir: path.resolve(configDir, config.sourceDir),
        distDir: path.resolve(configDir, config.distDir),
        viewsDir: path.resolve(configDir, config.viewsDir),
        assetsDir: assetsDir,
        configDir,
    });

    if (config.template) {
        config.template = path.resolve(configDir, config.template)
    }

    if (config.verbose) {
        console.log();
        console.log('Using config file:', configFilepath);
        console.log(prettyjson.render(config));
        console.log();
    }

    return config;
}

/**
 * Find config file: use file specified in the command line or try to find up the file tree.
 *
 * @param {Object} [file] File name.
 * @return {string} Config absolute file path.
 */
function findConfig(file) {
    if (file) {
        // Custom config location

        const configFilepath = file[0] === '/' ? file : path.join(process.cwd(), file);
        if (!fs.existsSync(configFilepath)) {
            throw new DvhbWebpackError('DvhbWebpack config not found: ' + configFilepath + '.');
        }

        return configFilepath;
    }

    // Search config file in all parent directories

    let configDir;
    try {
        configDir = findup.sync(__dirname, CONFIG_FILENAME);
    }
    catch (exception) {
        throw new DvhbWebpackError('DvhbWebpack config not found: ' + CONFIG_FILENAME + '.');
    }

    return path.join(configDir, CONFIG_FILENAME);
}

/**
 * Validate config.
 *
 * @param {Object} config Config options.
 */
function validateConfig(config) {
    if (config.extendWebpackConfig && typeof config.extendWebpackConfig !== 'function') {
        throw new DvhbWebpackError('DvhbWebpack: "extendWebpackConfig" option must be a function.');
    }
}

/**
 * Validate project’s Babel and Webpack versions.
 *
 * @param {string} configDir Config file directory.
 */
function validateDependencies(configDir) {
    const packageJsonPath = path.join(findup.sync(configDir, 'package.json'), 'package.json');
    const packageJson = require(packageJsonPath);
    DEPENDENCIES.forEach(validateDependency.bind(null, packageJson));
}

/**
 * Check versions of a project dependency.
 *
 * @param {Object} packageJson package.json.
 * @param {Object} dependency Dependency details.
 */
function validateDependency(packageJson, dependency) {
    const version = findDependency(dependency.package, packageJson);
    if (!version) {
        return;
    }

    let major;
    try {
        major = semverUtils.parseRange(version)[0].major;
    }
    catch (exception) {
        console.log('DvhbWebpack: cannot parse ' + dependency.name + ' version which is "' + version + '".');
        console.log('DvhbWebpack might not work properly. Please report this issue at ' + consts.BUGS_URL);
        console.log();
    }

    if (major < dependency.from) {
        throw new DvhbWebpackError('DvhbWebpack: ' + dependency.name + ' ' + dependency.from + ' is required, ' +
            'you are using version ' + major + '.');
    }
    else if (major > dependency.to) {
        console.log('DvhbWebpack: ' + dependency.name + ' is supported up to version ' + dependency.to + ', ' +
            'you are using version ' + major + '.');
        console.log('DvhbWebpack might not work properly, report bugs at ' + consts.BUGS_URL);
        console.log();
    }
}

/**
 * Find package in project’s dependencies or devDependencies.
 *
 * @param {string} name Package name.
 * @param {Object} packageJson package.json.
 * @returns {string}
 */
function findDependency(name, packageJson) {
    if (packageJson.dependencies && packageJson.dependencies[name]) {
        return packageJson.dependencies[name];
    }
    if (packageJson.devDependencies && packageJson.devDependencies[name]) {
        return packageJson.devDependencies[name];
    }
    return null;
}

module.exports = getConfig;