提问者:小点点

列表请求不工作(Mongoose in node.js with Typescript)


我在Nodejs中使用mongoose和打字脚本。在列表请求中,我有以下代码:

async list(req: Request, res: Response, next: NextFunction)
{
    try {
        let list: ListInterface[] = []
        await RequestModel.find().then(requests =>
        {
            requests.map(async request =>
            {
                const client = await Client.findById(request.cliente)
                const seller = await Seller.findById(request.vendedor)
                const company = await Company.findById(request.representada)
                const tmp =
                {
                    id: request._id,
                    data: request.data,
                    cliente: String(client?.nome_fantasia),
                    vendedor: String(seller?.nome),
                    representada: String(company?.nome_fantasia),
                    tipo: request.tipo,
                    status: request.status
                }
                list.push(tmp)
                console.log(tmp)
            })
        })
        console.log(list)
        return res.json(list)
    } catch (error) {
        next(error)
    }
}

当我在Insomnia中发出请求时,我收到一个空数组(在终端中--因为console.log(list)-以及在Insomnia的预览中):[]。在终端中,由于console.log(tmp)命令,我收到了正确的数据。

我已经尝试将列表声明为const list=request.map(。。。),但它在终端中给出了[promise<;pending>,promise<;pending>],在失眠中给出了[{},{}]。我不能重复这个测试完全相同的代码,但我记得那些结果。

我甚至不确定我在滥用哪种技术。有人能帮我解决这个问题吗?


共1个答案

匿名用户

.map函数返回承诺列表,因此在发送回响应之前必须等待它们。

null

async list(req: Request, res: Response, next: NextFunction)
{
    try {
        let list: ListInterface[] = []
        const requests = await RequestModel.find()
        
        // collect all promises from the loop
        const promises = requests.map(async request =>
        {
            const client = await Client.findById(request.cliente)
            const seller = await Seller.findById(request.vendedor)
            const company = await Company.findById(request.representada)
            const tmp =
            {
                id: request._id,
                data: request.data,
                cliente: String(client?.nome_fantasia),
                vendedor: String(seller?.nome),
                representada: String(company?.nome_fantasia),
                tipo: request.tipo,
                status: request.status
            }
            list.push(tmp)
            console.log(tmp)
        })
        
        // wait for all promises to complete
        await Promise.all(promises)
        
        console.log(list)
        return res.json(list)
    } catch (error) {
        next(error)
    }
}