{
  "workers": "workers"
}

{
  "workers": {
    "path": "workers",
    "isSubpackage": true  // true 表示把 worker 打包为分包。默认 false。填 false 时等同于 { "workers": "workers" }
  }
}

workers/request/index.js
workers/request/utils.js
workers/response/index.js

├── game.js
├── game.json
├── project.config.json
└── workers
    ├── request
    │   ├── index.js
    │   └── utils.js
    └── response
        └── index.js

const utils = require('./utils')

// 在 Worker 线程执行上下文会全局暴露一个 worker 对象，直接调用 worker.onMessage/postMessage 即可
worker.onMessage(function (res) {
  console.log(res)
})

const worker = wx.createWorker('workers/request/index.js') // 文件名指定 worker 的入口文件路径，绝对路径

var task = wx.preDownloadSubpackage({
   packageType: "workers", 
   success(res) {
      console.log("load worker success", res)
      var worker = wx.createWorker("workers/request/index.js")   // 创建 worker。 如果 worker 分包没下载完就调 createWorker 的话将报错
   },
   fail(res) {
      console.log("load worker fail", res)
   }
})

task.onProgressUpdate(res => {
  console.log(res.progress) // 可通过 onProgressUpdate 接口监听下载进度
  console.log(res.totalBytesWritten)
  console.log(res.totalBytesExpectedToWrite)
})

worker.postMessage({
  msg: 'hello worker'
})