Javascript - Filter arrays in object

Question

I'm trying to create an array of objects with filtered values

// desired output

     [
         { "2017-02-01": "09:00" },
         { "2017-02-02": "09:00" },
     ]

My Js object

let res = {
  "2018-02-01": [
    {
      "time": "09:00",
      "available": true,
    },
    {
      "time": "10:00",
      "available": false,
    }
  ],
  "2018-02-02": [
    {
      "time": "09:00",
      "available": true,
      "reference": null
    },
    {
      "time": "10:00",
      "available": false,
      "reference": null
    }
  ]
}

// My attempt 
output = _.keys(res).map( i => res[i].filter( t => t.available))

console.log(output); 

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.core.js"></script>

Answer 1

try this:

let res = {
  "2018-02-01": [
    {
      time: "09:00",
      available: true
    },
    {
      time: "10:00",
      available: false
    }
  ],
  "2018-02-02": [
    {
      time: "09:00",
      available: true,
      reference: null
    },
    {
      time: "10:00",
      available: false,
      reference: null
    }
  ]
};
let output = Reflect.ownKeys(res).map(key => ({
  [key]: res[key].filter(obj => obj.available)[0].time
}));
console.log(output);

your logic is basically correct with a little error because you didn't take a good control of your return value in map function.

And that is what i did:

[key]: /*basically  your code*/[0].time

Answer 2

If I understand correct, what you need is the first timeslot that is available.

For this, you can loop over keys of response. Post that you can use array.find or _.find and get first value that is available.

Now create an object with date value as key and value as object.time

let res = {
  "2018-02-01": [{
      "time": "09:00",
      "available": true,
    },
    {
      "time": "10:00",
      "available": false,
    }
  ],
  "2018-02-02": [{
      "time": "09:00",
      "available": true,
      "reference": null
    },
    {
      "time": "10:00",
      "available": false,
      "reference": null
    }
  ]
}

// My attempt 
output = Object.keys(res).reduce(function(acc, key) {
  const obj = res[key].find(x => !!x.available);
  if (!!obj)
    acc.push({
      [key]: obj.time
    });
  return acc;
}, [])

console.log(output);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.core.js"></script>

Answer 3

Iterate through the res object using for in loop. Find the object which has available as true using Array.find method. Store key/value in an object and push the object in an array.

let res = {
  "2018-02-01": [
    {
      "time": "09:00",
      "available": true,
    },
    {
      "time": "10:00",
      "available": false,
    }
  ],
  "2018-02-02": [
    {
      "time": "09:00",
      "available": true,
      "reference": null
    },
    {
      "time": "10:00",
      "available": false,
      "reference": null
    }
  ]
}

var arr = [];

for (var date in res) {
  arr.push({
    [date]: res[date].find(r => r.available).time
  });
}

console.log(arr);

Answer 4

If you want to do using native javascript then you can use this code -

var arr = [];
for (const [key, value] of Object.entries(res)) {
    var obj = {};

    for (const o of value) {

        if (o.available) { obj[key] = o.time; }
    } 

    arr.push(obj);
}

console.log(arr);