javascript - 我正在尝试将数组映射到另一个映射函数中我的代码未同步运行

Question

我有一组潜在客户详细信息(我需要将其插入数据库)并且每个潜在客户都有一个名为 interestArea 的字段，它是一个字符串数组，我必须找到每个 interestArea，如果从数据库中找到了 interestArea，我将不得不存储 interestArea 的 ObjectId，否则我将不得不在 db 中创建新的 interestArea 并将其 objectId 作为潜在客户的字段存储在 interestArea 中

我的意见

let jsonArray = [ { firstName: 'newLead1',
                    lastName: 'newLead1',
                    company: 'hub',
                    companySize: '22',
                    designation: 'software Enginner',
                    phoneNumber: '1234567890',
                    jobRole: 'engineer',
                    email: 'newLead1@hub.com',
                    leadSource: 'online',
                    industry: 'it',
                    location: 'ernakulam',
                    annualTurnOver: '10',
                    requestedMeetingDate: '2019-03-28T09:13:02.958Z',
                    interestArea: 'app,newspaper' },

                    { firstName: 'newLead2',
                      lastName: 'Sharma',
                      company: 'hub',
                      companySize: '20',
                      designation: 'software Enginner',
                      phoneNumber: '1234567891',
                      jobRole: 'engineer',
                      email: 'newLead2@hub.com',
                      leadSource: 'web',
                      industry: 'software',
                      location: 'kacherippady',
                      annualTurnOver: '15',
                      requestedMeetingDate: '2019-03-28T09:13:02.958Z',
                      interestArea: 'website,newspaper' } ]

下面是我试过的功能

function jsonArrayMap(jsonArray){
  return new Promise(function(resolve,reject){
      let validateInFn = [];
      (async ()=>{
        validateInFn = await jsonArray.map(lead => {
          (async ()=>{
            console.log("step: 1");
            console.log("interestArea is present",lead.interestArea);
            let interestAreaArray = lead.interestArea.split(',');
            console.log("interestAreaArray",interestAreaArray);
            let interestAreaObjectIdArrayInFn = await interestAreaArray.map(interestArea => {
              console.log("step: 2");
              console.log("each word interestArea",interestArea)
              InterestArea.find({where:{name:interestArea}},(err,interestAreaInDb)=>{
                console.log("step: 3");
                console.log("search in db got interestAreaInDb",interestAreaInDb);
                if(interestAreaInDb.length>0) {
                  console.log("step: 4");
                  return interestAreaInDb[0].id
                }
                else {
                  console.log("step: 4");
                  InterestArea.create({name:interestArea},(err,newInterestArea)=>{
                    return newInterestArea.id
                  });
                } //else
              }) //find is there an interestArea with this name
            }) //interestAreaArray.map
            console.log("interestAreaObjectIdArrayInFn",interestAreaObjectIdArrayInFn)
          })();
        })
        console.log("validateInFn",validateInFn)
      })();
    }) //promise
  } //jsonArrayMap

输出为

step: 1
interestArea is present app,newspaper
interestAreaArray [ 'app', 'newspaper' ]
step: 2
each word interestArea app
step: 2
each word interestArea newspaper
step: 1
interestArea is present website,newspaper
interestAreaArray [ 'website', 'newspaper' ]
step: 2
each word interestArea website
step: 2
each word interestArea newspaper
interestAreaObjectIdArrayInFn [ undefined, undefined ]
interestAreaObjectIdArrayInFn [ undefined, undefined ]
validateInFn [ undefined, undefined ]
step: 3
search in db got interestAreaInDb [ { name: 'app', id: 5ca799d2491c0cd8f415f980 } ]
step: 4
(node:56798) [DEP0079] DeprecationWarning: Custom inspection function on Objects via .inspect() is deprecated
step: 3
search in db got interestAreaInDb []
step: 4
step: 3
search in db got interestAreaInDb [ { name: 'website', id: 5ca799d2491c0cd8f415f981 } ]
step: 4
step: 3
search in db got interestAreaInDb []
step: 4

我期待代码在我使用它的地方等待，但它没有像我预期的那样工作

我也尝试过使用 async npm

我使用了他们的 forEachOf 函数，但也没有用

下面是我试过的功能

function jsonArrayMap(jsonArray){
      return new Promise(function(resolve,reject){
          let validateInFn = [];
          async.forEachOf(jsonArray, (lead, key, callbackforEachOfjsonArray) => {
            console.log("step: 1");
            console.log("interestArea is present",lead.interestArea);
            let interestAreaArray = lead.interestArea.split(',');
            console.log("interestAreaArray",interestAreaArray);
            let interestAreaObjectIdArrayInFn = [];

            async.forEachOf(interestAreaArray, (interestArea, key2, callbackforEachOfInterestAreaArray) => {
              console.log("step: 2");
              console.log("each word interestArea",interestArea)
              InterestArea.find({where:{name:interestArea}},(err,interestAreaInDb)=>{
                console.log("step: 3");
                console.log("search in db got interestAreaInDb",interestAreaInDb);
                if(interestAreaInDb.length>0) {
                  console.log("step: 4");
                  interestAreaObjectIdArrayInFn.push(interestAreaInDb[0].id)
                  if(interestAreaArray.length -1 == key2) callbackforEachOfInterestAreaArray()
                }
                else {
                  console.log("step: 4");
                  InterestArea.create({name:interestArea},(err,newInterestArea)=>{
                    interestAreaObjectIdArrayInFn.push(newInterestArea.id)
                    if(interestAreaArray.length -1 == key2) callbackforEachOfInterestAreaArray()
                  });
                } //else
              }) //find is there an interestArea with this name
            }, function (err,result2) {
              console.log("result2",result2)
              if(jsonArray.length -1 == key) callbackforEachOfjsonArray()
          })
        },function (err,result) {
          console.log("result",result)
        })
        }) //promise
      } //jsonArrayMap

输出为

step: 1
interestArea is present app,newspaper
interestAreaArray [ 'app', 'newspaper' ]
step: 2
each word interestArea app
step: 2
each word interestArea newspaper
step: 1
interestArea is present website,newspaper
interestAreaArray [ 'website', 'newspaper' ]
step: 2
each word interestArea website
step: 2
each word interestArea newspaper
step: 3
search in db got interestAreaInDb [ { name: 'app', id: 5ca799d2491c0cd8f415f980 } ]
step: 4
(node:56939) [DEP0079] DeprecationWarning: Custom inspection function on Objects via .inspect() is deprecated
step: 3
search in db got interestAreaInDb [ { name: 'newspaper', id: 5ca894c3aa7a64dddefa2674 } ]
step: 4
step: 3
search in db got interestAreaInDb [ { name: 'website', id: 5ca799d2491c0cd8f415f981 } ]
step: 4
step: 3
search in db got interestAreaInDb [ { name: 'newspaper', id: 5ca894c3aa7a64dddefa2674 } ]
step: 4

Answer 1

您的代码中存在一些错误:

1. 你构建了一个新的 Promise，尽管你不必这样做；如果您有包装的回调，只需构建一个。

2. 您确实调用了两个接受回调的函数，但您没有将它们包装在 new Promise 中。

3. 您等待 .map 的结果；这始终是一个空操作，因为 .map 返回一个数组，而 await 仅适用于 Promises。如果你有一个 promise 数组，你可以使用 Promise.all 并将它变成一个解析为数组的 promise；然后你可以await。

---

现在，您的代码无法轻易修复。因此，让我们从头开始。

首先，让我们将回调包装到 promise 中:

const findInterestArea = (name) => 
  new Promise((resolve, reject) => InterestArea.find({where: { name }}, (err, result)=> err ? reject(err) : resolve(result));

const createInterestArea = (name) => 
  new Promise((resolve, reject) => InterestArea.create({ name }, (err, result) => err ? reject(err) : resolve(result));

现在，下一步的抽象将是一个findOrInsert操作:

async function findOrCreateInterest(name) {
  const exists = await findInterestArea(name);
  if (exists) return exists;
  return await createInterestArea(name);
}

现在您可以轻松地遍历 jsonArray 和每个 interestArea 并将其插入:

async function jsonArrayMap(jsonArray) {
  for(const lead of jsonArray) {
    const interests = lead.interestArea.split(',');
    for (const interest of interests) {
      const { id } = await findorCreateInterest(interest);
      // do stuff with id
    }
  }
}