express中怎么通过Request来传值？

Question

export async function getAdmin(req: RequestAll, res: Response, next: Function){
    try{
        let data=req.body
        if(!data.username || !data.password){
            res.send("用户名或密码不能为空")
        }
        const postRepository = getManager().getRepository(Admin);
        // load posts
        const posts = await postRepository.findOne({username:data.username});
        if(!posts){
            res.send("该用户不存在")
        }
        if(md5(data.password)!==posts.password){
            res.send("密码输入不正确")
        }
        posts.token=await jwt.sign(
            {id:posts.id},
            config.jwtSecret,
            {expiresIn:1800}
        )
        await postRepository.save(posts)
        // console.log(token)
        // return loaded posts
        delete  posts.password
        req.user=posts
        console.log(req.user)
        res.status(200).json({
            'code':0,
            "data":posts,
            "msg":"登录成功"
        })
    }catch (e) {
        next(e)
    }
}

我把拿到的用户信息想一直通过req也就是Request传下去，所以这样写了：req.user=posts

但是为什么我的不行呢？？