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Filter out non null objects from array of objects

I have list of objects in an array. How can i filter out if any one of key property of the object is null/empty. In given example the first record is perfect and the 2nd and 4th record have missing properties. So my ideal output should be 1st & 2nd.
[{
"ServiceArea": "NON-CIO",
"ManagingDirector": "qwe",
"Lead": "abc",
"Manager": "xyz"
"id":"1",
"Designation":"COO"
},
{
"ServiceArea": "NON-CIO",
"ManagingDirector": "dfg",
"Lead": "",
"Manager": "lkj"
"id":"2",
"Designation":"CTO"
},
{
"ServiceArea": "NON-CIO",
"ManagingDirector": "out",
"Lead": "poi",
"Manager": "",
"id":"43",
"Designation":"COO"
},
{
"ServiceArea": "4500-CIO",
"ManagingDirector": "yhh",
"Lead": "trr",
"Manager": "nbb"
"id":"403",
"Designation":"CTO"
}
]

Use Array.filter, then use Array.every to check whether every value is truthy.
const arr=[{ServiceArea:"NON-CIO",ManagingDirector:"qwe",Lead:"abc",Manager:"xyz",id:"1",Designation:"COO"},{ServiceArea:"NON-CIO",ManagingDirector:"dfg",Lead:"",Manager:"lkj",id:"2",Designation:"CTO"},{ServiceArea:"NON-CIO",ManagingDirector:"out",Lead:"poi",Manager:"",id:"43",Designation:"COO"},{ServiceArea:"4500-CIO",ManagingDirector:"yhh",Lead:"trr",Manager:"nbb",id:"403",Designation:"CTO"}];
const res = arr.filter(e => Object.values(e).every(k => !!k))
console.log(res)
If you want to filter by specific keys, you can store the keys in an array and use Array.every to check if all values are truthy.
const arr=[{ServiceArea:"NON-CIO",ManagingDirector:"qwe",Lead:"abc",Manager:"xyz",id:"1",Designation:"COO"},{ServiceArea:"NON-CIO",ManagingDirector:"dfg",Lead:"",Manager:"lkj",id:"2",Designation:"CTO"},{ServiceArea:"NON-CIO",ManagingDirector:"out",Lead:"poi",Manager:"",id:"43",Designation:"COO"},{ServiceArea:"4500-CIO",ManagingDirector:"yhh",Lead:"trr",Manager:"nbb",id:"403",Designation:"CTO"}];
const keys = ["Lead"]
const res = arr.filter(e => keys.every(k => !!e[k]))
console.log(res)

How to push JSON data in two dimensional array?

I am trying to get a structure like
var tableData= [
['Hfbj'],
['Hygh'],
[6],
['mayur'],
[2563458952]
]
Here is my JSON data:
data:{
"address"': "Hfbj"
"id": 6
"landmark": "Hygh"
"name": "mayur"
"phone": 2563458952
"title": "aaa"
}
I am using react-native-table-component in which that type of structure needed. For that, I am doing the following but it showing data.map is not function and undefined.
let newdata = this.state.tableData[0].push(
[responseJson.data.title],
[responseJson.data.title]
);
this.setState({
tableData: newdata
});
How can I achieve it?

You could make use of Object.values and Array.map:
var reponseJson = {
data: {
"address": "Hfbj",
"id": 6,
"landmark": "Hygh",
"name": "mayur",
"phone": 2563458952,
"title": "aaa"
}
};
var newData = Object.values(reponseJson.data)
.map(item => [item]);
console.log(newData);
Note that I used the responseJson name to match your question, but as #Andreas pointed out, this is an object, not JSON.
If you need only certain columns (as requested in the comments below), use Object.keys and Array.filter on them before rebuilding the array:
var reponseJson = {
data: {
"address": "Hfbj",
"id": 6,
"landmark": "Hygh",
"name": "mayur",
"phone": 2563458952,
"title": "aaa"
}
};
var keysToKeep = ['address', 'landmark', 'title'];
var newData = Object.keys(reponseJson.data)
.filter(key => keysToKeep.includes(key))
.map(key => [reponseJson.data[key]]);
console.log(newData);

.map Is for arrays, whereas your responseJson.data is an Object. To get turn that Object into an array of its values you can do Object.values(responseJson.data)

Merge objects with corresponding key values from two different arrays of objects

I've got two arrays that have multiple objects
[
{
"name":"paul",
"employee_id":"8"
}
]
[
{
"years_at_school": 6,
"department":"Mathematics",
"e_id":"8"
}
]
How can I achieve the following with either ES6 or Lodash?
[
{
"name":"paul",
"employee_id":"8"
"data": {
"years_at_school": 6
"department":"Mathematics",
"e_id":"8"
}
}
]
I can merge but I'm not sure how to create a new child object and merge that in.
Code I've tried:
school_data = _.map(array1, function(obj) {
return _.merge(obj, _.find(array2, {employee_id: obj.e_id}))
})
This merges to a top level array like so (which is not what I want):
{
"name":"paul",
"employee_id":"8"
"years_at_school": 6
"department":"Mathematics",
"e_id":"8"
}
The connector between these two is "employee_id" and "e_id".
It's imperative that it's taken into account that they could be 1000 objects in each array, and that the only way to match these objects up is by "employee_id" and "e_id".

In order to match up employee_id and e_id you should iterate through the first array and create an object keyed to employee_id. Then you can iterate though the second array and add the data to the particular id in question. Here's an example with an extra item added to each array:
let arr1 = [
{
"name":"mark",
"employee_id":"6"
},
{
"name":"paul",
"employee_id":"8"
}
]
let arr2 = [
{
"years_at_school": 6,
"department":"Mathematics",
"e_id":"8"
},
{
"years_at_school": 12,
"department":"Arr",
"e_id":"6"
}
]
// empObj will be keyed to item.employee_id
let empObj = arr1.reduce((obj, item) => {
obj[item.employee_id] = item
return obj
}, {})
// now lookup up id and add data for each object in arr2
arr2.forEach(item=>
empObj[item.e_id].data = item
)
// The values of the object will be an array of your data
let merged = Object.values(empObj)
console.log(merged)

If you perform two nested O(n) loops (map+find), you'll end up with O(n^2) performance. A typical alternative is to create intermediate indexed structures so the whole thing is O(n). A functional approach with lodash:
const _ = require('lodash');
const dataByEmployeeId = _(array2).keyBy('e_id');
const result = array1.map(o => ({...o, data: dataByEmployeeId.get(o.employee_id)}));

Hope this help you:
var mainData = [{
name: "paul",
employee_id: "8"
}];
var secondaryData = [{
years_at_school: 6,
department: "Mathematics",
e_id: "8"
}];
var finalData = mainData.map(function(person, index) {
person.data = secondaryData[index];
return person;
});
Sorry, I've also fixed a missing coma in the second object and changed some other stuff.
With latest Ecmascript versions:
const mainData = [{
name: "paul",
employee_id: "8"
}];
const secondaryData = [{
years_at_school: 6,
department: "Mathematics",
e_id: "8"
}];
// Be careful with spread operator over objects.. it lacks of browser support yet! ..but works fine on latest Chrome version for example (69.0)
const finalData = mainData.map((person, index) => ({ ...person, data: secondaryData[index] }));

Your question suggests that both arrays will always have the same size. It also suggests that you want to put the contents of array2 within the field data of the elements with the same index in array1. If those assumptions are correct, then:
// Array that will receive the extra data
const teachers = [
{ name: "Paul", employee_id: 8 },
{ name: "Mariah", employee_id: 10 }
];
// Array with the additional data
const extraData = [
{ years_at_school: 6, department: "Mathematics", e_id: 8 },
{ years_at_school: 8, department: "Biology", e_id: 10 },
];
// Array.map will iterate through all indices, and gives both the
const merged = teachers.map((teacher, index) => Object.assign({ data: extraData[index] }, teacher));
However, if you want the data to be added to the employee with an "id" matching in both arrays, you need to do the following:
// Create a function to obtain the employee from an ID
const findEmployee = id => extraData.filter(entry => entry.e_id == id);
merged = teachers.map(teacher => {
const employeeData = findEmployee(teacher.employee_id);
if (employeeData.length === 0) {
// Employee not found
throw new Error("Data inconsistency");
}
if (employeeData.length > 1) {
// More than one employee found
throw new Error("Data inconsistency");
}
return Object.assign({ data: employeeData[0] }, teacher);
});

A slightly different approach just using vanilla js map with a loop to match the employee ids and add the data from the second array to the matching object from the first array. My guess is that the answer from #MarkMeyer is probably faster.
const arr1 = [{ "name": "paul", "employee_id": "8" }];
const arr2 = [{ "years_at_school": 6, "department": "Mathematics", "e_id": "8" }];
const results = arr1.map((obj1) => {
for (const obj2 of arr2) {
if (obj2.e_id === obj1.employee_id) {
obj1.data = obj2;
break;
}
}
return obj1;
});
console.log(results);

converting array to object while considering keys of the same value

I am trying to figure out an easy way to convert an array of objects to an object
I have an array of objects that looks like this:
[
{
"id": "-LP9_kAbqnsQwXq0oGDT",
"value": Object {
"date": 1541482236000,
"title": "First",
},
},
.... more objects here
]
And id like to convert it to an object with the timestamps as the keys, and arrays of objects corresponding to that date. If that key already exists, then add the object to the corresponding array associated with that key
{
1541482236000:
[{
"id": "-LP9_kAbqnsQwXq0oGDT",
"value": Object {
"date": 1541482236000,
"title": "First",
},
},
{
"id": "-LP9_kAbqnsQwXqZZZZ",
"value": Object {
"date": 1541482236000,
"title": "Some other title",
},
},
.... more objects here
],
1541482236001:
[{
"id": "-LP9_kAbqnsQ1234",
"value": Object {
"date": 1541482236001,
"title": "Another title",
},
},
.... more objects here
]
}
I was able to achieve something similar using reduce. However it does not handle adding objects to the array when their key already exists.
calendarReminders = action.value.reduce((obj, reminder) => {
dateKey = moment(reminder.value.date).format('YYYY-MM-DD')
obj[dateKey] = [reminder]
return obj;
}, {});
How can I do this?

You just need to check whether the object is already a key and if not add it with the value of an array. Then you can just push() into it:
let arr = [{"id": "-LP9_kAbqnsQwXq0oGDT","value": {"date": 1541482236000,"title": "First",},},{"id": "SomID","value": {"date": 1541482236000,"title": "Some other title",},},{"id": "A different ID","value": {"date": 1541482236001,"title": "A third title",},}]
let calendarReminders = arr.reduce((obj, reminder) => {
(obj[reminder.value.date] || (obj[reminder.value.date] = [])).push(reminder)
return obj;
}, {});
console.log(calendarReminders)
If you want to set the keys to a different format with moment, you should be able to do that without changing the basic idea.

Please test the below code!
First you iterate through your array of data,
if your result object/dictionary already has the key then you just add the current item
otherwise you make the key and set the value
const data = [];
let result = {};
for (const item of data) {
const key = item.value.date;
if (result.hasOwnProperty(key)) {
const prevData = result[key];
result[key] = [...prevData, item];
} else {
result[key] = [item];
}
}

How to create a new json out of three jsons?

I have 3 different jsons, I need to extrapolate some data from each and create a new json with it. The three jsons have an id identifier in common, a unique identifier, so We could use that as a match since they are actually three different big jsons.
On json one we have "id":"265", on two and three "article_id":"265", so these can be the reference point when we loop.
I never worked with json this way so I wouldn't know how to approach it. I have put jQuery and JS as tags as they're what I know best.
1
{
"id":"265",
"title":"Battle of Gettysburg",
"page_id":"4849",
"language_id":"en",
"original_time":"July 1\u20133, 1863"
}
2
{
"id":"185",
"original_name":"United States",
"country_id":"24",
"article_id":"265"
}
3
{
"id":"73",
"month":"July",
"year":"1863",
"suffix":"",
"article_id":"265"
}
So the end result I am looking for is a single json exactly like this, we take id and title as objects from json 1, then we grab original_name from json two and year object from json three and we'll have:
{
"id":"265",
"title":"Battle of Gettysburg",
"original_name":"United States",
"year":"1863"
}
NOTE
The json above are just examples, in reality they are three huge lists, what I could do (manually), is to join them in order to have a single json.

There is some terminology confusion here; based on your comments you could be asking one of two very different questions. Fortunately one of them is very simple to answer so let's do both.
(I am handwaving past the details of loading json strings into the browser and converting them into javascript objects.)
If you have three objects
...then this is just a matter of plucking out the fields you need individually when constructing an output object:
var in1 = {
"id": "265",
"title": "Battle of Gettysburg",
"page_id": "4849",
"language_id": "en",
"original_time": "July 1\u20133, 1863"
};
var in2 = {
"id": "185",
"original_name": "United States",
"country_id": "24",
"article_id": "265"
}
var in3 = {
"id": "73",
"month": "July",
"year": "1863",
"suffix": "",
"article_id": "265"
}
// construct a new object using the selected fields
// from each object in1, in2, or in3:
var out = {
id: in1.id,
title: in1.title,
original_name: in2.original_name,
year: in3.year
}
console.log(out);
If you have three lists of objects:
...in this case it's a lot more complicated (and a lot more interesting). In this case you would need to match fields from the objects in each list which share the same IDs.
The following is definitely not the most efficient or memory-conserving way to do this; I've spread things out to (hopefully) make it easier to follow what it's doing.
I'm making two assumptions:
within each list, all IDs are unique (meaning you won't have two objects with the same ID in one JSON file)
Every ID will appear in all three lists (meaning you don't need to handle missing fields in output)
/* Again handwaving past loading JSON strings and parsing
them into javascript objects, we'll just start with
three arrays: */
var input1 = [{
"id": "265",
"title": "Battle of Gettysburg",
"page_id": "4849",
"language_id": "en",
"original_time": "July 1\u20133, 1863"
},
{
"id": "1",
"title": "Foo",
"page_id": "123",
"language_id": "en",
"original_time": "July 1\u20133, 1863"
}
];
var input2 = [{
"id": "1",
"original_name": "Bar",
"country_id": "24",
"article_id": "265"
},
{
"id": "265",
"original_name": "United States",
"country_id": "24",
"article_id": "265"
}
]
var input3 = [{
"id": "1",
"month": "July",
"year": "Baz",
"suffix": "",
"article_id": "265"
},
{
"id": "265",
"month": "July",
"year": "1863",
"suffix": "",
"article_id": "265"
}
]
/* It would be much easier to find corresponding IDs
across these arrays if they weren't arrays. We'll
start by converting them into objects keyed by the
item ids: */
var convertArray = function(arr) {
var output = {};
arr.forEach(function(o) {
output[o.id] = o;
});
return output;
}
var obj1 = convertArray(input1);
var obj2 = convertArray(input2);
var obj3 = convertArray(input3);
/* Now if we need to find (say) the object with id "foo", we don't
need to search the whole array, but can just use `obj1["foo"]` or
`obj1.foo`.
The last step is to iterate over the list of IDs and repeatedly
do basically the same thing as in the "if you have three objects"
part above. The only difference is that we need to access the
object with the same ID in each of the input lists: */
var constructOutput = function(in1, in2, in3) {
var output = []; // we'll be outputting a list of objects again.
// step through every ID (assuming in1 contains all of them):
Object.keys(in1).forEach(function(id) {
var obj = {
id: id,
title: in1[id].title,
original_name: in2[id].original_name,
year: in3[id].year
}
output.push(obj);
});
return output;
}
var final = constructOutput(obj1, obj2, obj3)
console.log(final)

Essentially what you have to do is mimic a SQL JOIN using JavaScript objects:
Use JSON.parse() on all three JSON collections to turn them into arrays of objects.
Iterate through JSON 1 objects; for each object...
Iterate through JSON 2 objects, testing if article ID matches the ID from JSON 1 that we are iterating over. Save this object.
Iterate through JSON 3 objects, testing if ID matches the ID of the object we found from JSON 2. Save this object.
After you have all three objects, make a new object literal that contains only the fields you want:
{
Id: obj1.id,
Title: obj1.title,
Original_name: obj2.original_name,
Year: obj3.year
}

Should you want to combine n number of JSON objects, e.g. a list of objects you can take a functional approach and utilise reduce + filter.
const data = [{
"id":"265",
"title":"Battle of Gettysburg",
"page_id":"4849",
"language_id":"en",
"original_time":"July 1\u20133, 1863"
},
{
"id":"185",
"original_name":"United States",
"country_id":"24",
"article_id":"265"
},
{
"id":"73",
"month":"July",
"year":"1863",
"suffix":"",
"article_id":"265"
}];
const final = data.reduce((accu, { id, title }, index, array) => {
// Find any related objects
const matches = array.filter(data => data.article_id === id);
if (matches.length) {
// Flatten them for ease of access. Duplicate keys will override.
const flat = matches.reduce((arr, item) => ({ ...arr, ...item }), [])
// Return new object
return accu.concat({
...flat,
id,
title,
});
}
return accu;
}, []);
console.log(final, '<<')
// Witness
document.getElementById('results').innerHTML = JSON.stringify(final);
<div id="results" style="font-family: Courier; font-size 14px; color: #fff; background: #000; padding: 20px; max-width: 80vw;"></div>

Edited*
Maybe this is what you need?
let arrPages = [{
"id":"265",
"title":"Battle of Gettysburg",
"page_id":"4849",
"language_id":"en",
"original_time":"July 1\u20133, 1863"
}];
let arrArticles = [{
"id":"185",
"original_name":"United States",
"country_id":"24",
"article_id":"265"
},
{
"id":"73",
"month":"July",
"year":"1863",
"suffix":"",
"article_id":"265"
}];
let getResult = (arrInput, arrCompare) => {
let joinedItems = [];
arrInput.forEach(item => {
let newItem = { id: item.id, title: item.title };
arrCompare.forEach(subItem => {
if(subItem.article_id !== undefined && subItem.article_id === item.id){
if(subItem.original_name !== undefined)
newItem.original_name = subItem.original_name;
if(subItem.year !== undefined)
newItem.year = subItem.year;
}
});
joinedItems.push(newItem);
});
return joinedItems;
};
let result = getResult(arrPages, arrArticles);
console.log(result);

In the first part of the code i create a var that has the json data.
To solve the problema i create 2 functions, the order of the creation dosen't metter, the first function getJSONData() take the json data as parameter and return a object filtered by the keys defined in the array keys. The secound function just check if the current key is present in the array of keys, this function could be replaced by the jQuery.inArray() method.
// JSON data
var json = [{
"id":"265",
"title":"Battle of Gettysburg",
"page_id":"4849",
"language_id":"en",
"original_time":"July 1\u20133, 1863"
},
{
"id":"185",
"original_name":"United States",
"country_id":"24",
"article_id":"265"
},
{
"id":"73",
"month":"July",
"year":"1863",
"suffix":"",
"article_id":"265"
}]
// keys that i want
var keys = ["title", "original_name", "year"];
// var that will have the filtered data
var newJSON = getJSONData(json);
console.log(JSON.stringify(newJSON))
// this is the main function of the code
// here we iterate in the json creating a new object that has all the tags definid in the keys array
function getJSONData(arrayJSON){
var JSONFiltered = {};
for(var i in arrayJSON){
for(var key in arrayJSON[i]){
if(hasElement(key)){
JSONFiltered[key] = arrayJSON[i][key];
}
}
}
return JSONFiltered;
}
// this function is used to check a key is present in the array of keys
function hasElement(key){
for(var elem in keys){
if(keys[elem] == key) return true;
}
return false;
}