vue-cli/packages/@vue/cli-service/lib/Service.js

const fs = require('fs')
const path = require('path')
const debug = require('debug')
const chalk = require('chalk')
const dotenv = require('dotenv')
const getPkg = require('read-pkg-up')
const merge = require('webpack-merge')
const Config = require('webpack-chain')
const PluginAPI = require('./PluginAPI')
const { info, warn, error } = require('@vue/cli-shared-utils')

module.exports = class Service {
  constructor () {
    this.webpackConfig = new Config()
    this.webpackChainFns = []
    this.webpackRawConfigFns = []
    this.devServerConfigFns = []
    this.commands = {}

    const pkg = getPkg.sync()
    this.pkg = pkg.pkg || {}
    this.context = path.dirname(pkg.path)
    this.projectOptions = this.loadProjectConfig()
    debug('vue:project-config')(this.projectOptions)

    // load base .env
    this.loadEnv()

    // install plugins
    this.resolvePlugins().forEach(({ id, apply }) => {
      apply(new PluginAPI(id, this), this.projectOptions)
    })

    // apply webpack configs from project config file
    if (this.projectOptions.chainWebpack) {
      this.webpackChainFns.push(this.projectOptions.chainWebpack)
    }
    if (this.projectOptions.configureWebpack) {
      this.webpackRawConfigFns.push(this.projectOptions.configureWebpack)
    }
  }

  loadEnv (mode) {
    const basePath = path.resolve(this.context, `.env${mode ? `.${mode}` : ``}`)
    const localPath = `${basePath}.local`
    const baseRes = dotenv.load({ path: basePath })
    const localRes = dotenv.load({ path: localPath })

    const checkError = res => {
      // only ignore if file is not found
      if (res.error && res.error.toString().indexOf('ENOENT') < 0) {
        error(res.error)
      }
    }

    checkError(baseRes)
    checkError(localRes)

    const logger = debug('vue:env')
    if (baseRes.parsed) {
      logger(basePath, baseRes.parsed)
    }
    if (localRes.parsed) {
      logger(localPath, localRes.parsed)
    }
  }

  resolvePlugins () {
    const builtInPlugins = [
      './command-plugins/serve',
      './command-plugins/build',
      './command-plugins/inspect',
      './command-plugins/help',
      // config plugins are order sensitive
      './config-plugins/base',
      './config-plugins/css',
      './config-plugins/dev',
      './config-plugins/prod'
    ]
    const prefixRE = /^(@vue\/|vue-)cli-plugin-/
    const projectPlugins = Object.keys(this.pkg.dependencies || {})
      .concat(Object.keys(this.pkg.devDependencies || {}))
      .filter(p => prefixRE.test(p))
    return builtInPlugins.concat(projectPlugins).map(id => ({
      id: id.replace(/^.\//, 'built-in:'),
      apply: require(id)
    }))
  }

  run (name, args) {
    let command = this.commands[name]
    if (!command && name) {
      error(`command "${name}" does not exist.`)
    }
    if (!command || args.help) {
      command = this.commands.help
    } else {
      args._.shift() // remove command itself
    }
    const { fn } = command
    return fn(args)
  }

  resolveWebpackConfig () {
    // apply chains
    this.webpackChainFns.forEach(fn => fn(this.webpackConfig))
    // to raw config
    let config = this.webpackConfig.toConfig()
    // apply raw config fns
    this.webpackRawConfigFns.forEach(fn => {
      if (typeof fn === 'function') {
        // function with optional return value
        config = fn(config) || config
      } else if (fn) {
        // merge literal values
        config = merge(config, fn)
      }
    })
    return config
  }

  loadProjectConfig () {
    // vue.config.js
    let fileConfig, pkgConfig
    const configPath = path.resolve(this.context, 'vue.config.js')
    if (fs.existsSync(configPath)) {
      fileConfig = require(configPath)
      if (!fileConfig || typeof fileConfig !== 'object') {
        error(
          `Error loading ${chalk.bold('vue.config.js')}: should export an object.`
        )
        fileConfig = null
      }
    }

    // package['vue-cli']
    pkgConfig = this.pkg['vue-cli']
    if (pkgConfig && typeof pkgConfig !== 'object') {
      error(
        `Error loading vue-cli config in ${chalk.bold(`package.json`)}: ` +
        `the "vue-cli" field should be an object.`
      )
      pkgConfig = null
    }

    if (fileConfig) {
      if (pkgConfig) {
        warn(
          `"vue-cli" field in ${chalk.bold(`package.json`)} ignored ` +
          `due to presence of ${chalk.bold('vue.config.js')}.`
        )
      }
      info(`Using project config in ${chalk.bold('vue.config.js')}.`)
      return fileConfig
    } else if (pkgConfig) {
      info(`Using project config from "vue-cli" field in ${chalk.bold(`package.json`)}.`)
      return pkgConfig
    } else {
      return {}
    }
  }
}