lambda-service/src/getConfig/watch.js

import chokidar from 'chokidar'
import { join, isAbsolute } from 'path'

// 按 key 存，值为数组
const watchers = {}

function toAbsolute(p) {
  if (isAbsolute(p)) {
    return p
  }
  return join(process.cwd(), p)
}

export function watch(key, files) {
  if (process.env.WATCH_FILES === 'none') return
  if (!watchers[key]) {
    watchers[key] = []
  }
  const { APP_ROOT } = process.env
  const watcher = chokidar.watch(files, {
    ignoreInitial: true,
    cwd: APP_ROOT ? toAbsolute(APP_ROOT) : process.cwd()
  })
  watchers[key].push(watcher)
  return watcher
}

export function unwatch(key) {
  if (!key) {
    return Object.keys(watchers).forEach(unwatch)
  }
  if (watchers[key]) {
    watchers[key].forEach(watcher => {
      watcher.close()
    })
  }
}