Sequelize 在創建多個子對象時獲取父引用

Question

我正在創建一組 Sequelize model 作為下面的鏈。 創建所有子模型后，如果成功，我想將其重定向到父模型的詳細信息頁面（發票）。 問題是因為我使用了一個循環，我怎么知道所有的孩子都被正確創建來進行重定向？ 在重定向代碼中，我也想訪問父 ID。

Invoice.create({
    //set parent properties
}).then(invoice => { //update company id
    return Company.findOne({where: {id: id}}).then(company => {
        //console.log('setting the company...')
        return invoice.setCompany(company).then(invoice => {return invoice})
    })
}).then(invoice => { //create order items
    orderItems.each((i, v) => {
        invoice.createOrderItem({
        }).then(orderItem => {
            return Product.findOne({where: {id: v.companyId).then(product => {
                //console.log('setting the product...')
                return orderItem.setProduct(product).then(orderItem => {return orderItem})                       
            })
        }).then(orderItem => {
            return Unit.findOne({where: {id: v.unitId}).then(unit => {
                //console.log('setting the unit...')
                return orderItem.setUnit(unit).then(orderItem => {return invoice})
            })
        }).then(invoice => {
            //console.log('returning invoice: ' + invoice)
            return invoice
        }).catch(errOI => {
            console.log('Error while creating order items: ' + errOI)
        })
    })
}).then(invoice => {
    //redirect to detail page
    console.log('I: ' + invoice)
}).catch(errI => {
    console.log('Error while creating invoice: ' + errI)
})

Answer 1

1. 創建一個 Promise 方法，一旦創建子記錄就解決了。
2. 循環 orderItems 並調用 Promise 方法，
3. 使用 Promise.all 解決所有的承諾。

function createChild(v) {
    return new Promise((resolve, reject) => {
        invoice.createOrderItem({})
        .then(orderItem => {
            return Product.findOne({where: {id: v.companyId).then(product => {
                //console.log('setting the product...')
                return orderItem.setProduct(product).then(orderItem => {return orderItem})                       
            })
        })
        .then(orderItem => {
            return Unit.findOne({where: {id: v.unitId}).then(unit => {
                //console.log('setting the unit...')
                return orderItem.setUnit(unit).then(orderItem => {return invoice})
            })
        })
        .then(invoice => {
            //console.log('returning invoice: ' + invoice)
            return invoice;
        })
        .then(invoice => {
            resolve();
        })
        .catch(errOI => {
            console.log('Error while creating order items: ' + errOI)
            reject();
        })
    });
}

Invoice.create({
    //set parent properties
}).then(invoice => { //update company id
    return Company.findOne({where: {id: id}}).then(company => {
        //console.log('setting the company...')
        return invoice.setCompany(company).then(invoice => {return invoice})
    })
}).then(invoice => { //create order items
    return orderItems.map(v => {
        return createChild(v);
    })
}).then(promises => {
    return Promise.all(promises)
    .then(done => {
        // direct the page
    })
})
}).catch(errI => {
    console.log('Error while creating invoice: ' + errI)
})