不了解如何在异步函数中返回对函数数组的答案

Question

I'm trying to create a new array object in my Promise function and I'm also trying to add user parameters from the getUser function.

I'm struggling to get the data into the array.

Could someone give me an example of how I could implement this?

Thanks.

      var results_array = [];
    return callHistory(76).then((result)=>{
        _.map(result, (item, index) => {
            var obj = JSON.parse(item.params);
            results_array[index] = {
                 id: item.id,
                 status: item.status,
                 timestamp: item.timestamp,
                 from_id:obj.from_id,
                 to_id: obj.to_id,
                 conference: obj.conference,
                 to:"",
                 from:getUser(10)

            };
        });


        res.json({
            status: 1,
            result: results_array
        })
        //return results_array;
    })

function getUser(id){

        return new Promise(function (resolve, reject) {
            connection.query(`SELECT * FROM members WHERE id = ${id} `, function (error, results, fields) {
                if (error) reject(error);
                return resolve(results);
            });
        });

    }

Answer 1

At first lets beautify getUser a bit:

function getUser(id){
  return connection.query(`SELECT * FROM members WHERE id = ${id} `);
}

Async await can also be used in loops making your main loop more elegant too:

async function getHistory(index){
  const history = await callHistory(index), result = [];

  for(const call of history){
    const params = JSON.parse( call.params );
    params.to = "";
    params.from = await getUser( 10 /*params.from*/ );

    result.push( params );
  }
  return result;
}

Usable as:

getHistory(76)
  .then( result => res.json({status:1, result })
  .catch( error => res.json({status:500, error });