使用koa起webpack服务的时候 如何控制webpack打包完成后再执行中间键方法

Question

• 在往koa全局ctx.state挂在ver.json的时候 webpack中哈希版本文件还没有生成
• 怎么控制执行顺序

// json plugin
const fs = require('fs');
const path = require('path');

class BuildEndPlugin {
    constructor(props) {
        this.filename = props.filename;
    }
    fn(compilation) {
        const currentPath = path.resolve(__dirname, `../public/${this.filename}`);
        const chunkName = {};
        const chunkObj = compilation.chunks;
        chunkObj.forEach(item => {
            Object.assign(chunkName, {
                [item.name]: item.hash
            });
        });
        if (!fs.existsSync(currentPath)) {
            fs.mkdir(`public/version`, () => {
                fs.writeFile(currentPath, JSON.stringify(chunkName));
            });
        }
        fs.writeFile(currentPath, JSON.stringify(chunkName));
    }
    apply(compiler) {
        const afterEmit = (compilation, cb) => {
            this.fn(compilation);
            cb();
        }
        compiler.plugin('after-emit', afterEmit);
    }
}

module.exports = BuildEndPlugin;

// app.js 挂载

app.use(async (ctx, next) => {
  Object.assign(ctx.state, {
    version
  });
  await next();
});

// webpack new 插件
new CreateJsonPlugin({
  filename: 'version/dev-ver.json'
}),

Answer 1

重启电脑试试？

Answer 2

await new Promise((res) => {
    setTimeout(() => {
      res();
    }, 0);
  });

放在挂在hash前面
弟弟回答