Return Promises instead of Async

2019-09-14 07:46发布

问题:

I want to return data which will look something like this

[
  shops: {
    id,
    products:[{Object}, {Object}]
  },
  shops: {
    id,
    products:[{Object}, {Object}]
  } 
]

So I have list of shop ids on which I need to iterate and get the products for each shop and append it and then return.

This is how I have done

const shops = response.data
const respToSend = []
async.eachSeries(shops, (shop, callback) => {
  const id = shop.shop_id
  const shopObj = {
    id
  }

  // Fetch products of each Shop.
  getProductList(id)
    .then((responseData) => {
      shopObj.products = responseData.data.products
      respToSend.push(shopObj)
      callback()
    })
    .catch(() => {
    })
}, () => {
  return respToSend
})

As you can see that I am using async node module for doing the async task but the application requires from me to return response as Promises which will then be resolved otherwise it prints null. How can I achieve this using promises? I am new to promises so sorry for any typo.

回答1:

try Promise.all(iterable)

Promise.all(shops.map(shop => getProductList(shop.shop_id)
    .then(products => ({id: shop.shop_id, products}))
    .then(/* actions for each shop */))
  .then(shops => {
    /* actions for array of shop objects */
    respToSend = shops;
  })