I have this sought of array
{
"arr": [
{
"obj": [
{
"reg_at": 1519615460064,
"id": "367790083"
},
{
"reg_at": 1519615460064,
"id": "41370460"
}
]
},
{
"obj": [
{
"reg_at": 1519615460065,
"id": "215109021"
},
{
"reg_at": 1519615460065,
"id": "72173002"
}
]
}
]
}
and i want to all the id objects into one array like this:
[367790083, 41370460, 41370460]
please how do i go about achieving this using nodejs? i have tried looping through but am not getting the desired output.
Thanks for your help.
Use reduce and map
var output = obj.arr.reduce( (a, c) =>
a.concat( c.obj.map(
s => +s.id ) ) , [])
Explanation
Use reduce to iterate and accumulate the output to a
Use map to return the id (number converted) of every item in obj array inside arr
Demo
var obj = {
"arr": [
{
"obj": [
{
"reg_at": 1519615460064,
"id": "367790083"
},
{
"reg_at": 1519615460064,
"id": "41370460"
}
]
},
{
"obj": [
{
"reg_at": 1519615460065,
"id": "215109021"
},
{
"reg_at": 1519615460065,
"id": "72173002"
}
]
}
]
};
var output = obj.arr.reduce( (a, c) =>
a.concat( c.obj.map(
s => +s.id ) ) , []);
console.log( output );
Seeing that you are a beginner I'll do this the good old fashioned way for you to understand how the data is organized.
var data = {
"arr": [
{
"obj": [
{
"reg_at": 1519615460064,
"id": "367790083"
},
{
"reg_at": 1519615460064,
"id": "41370460"
}
]
},
{
"obj": [
{
"reg_at": 1519615460065,
"id": "215109021"
},
{
"reg_at": 1519615460065,
"id": "72173002"
}
]
}
]
};
// The variable for the result
var result = [];
// "data" is the object and "arr" is an array and has a length
for (var i=0; i<data.arr.length; i++) {
// For clarity, pick the current object from the array
var theArrItem = data.arr[i];
// That object then has a "obj" which is an array
for (var j=0; j<theArrItem.obj.length; j++) {
// Again, pick the current object
var theObjItem = theArrItem.obj[j];
// Add the id of the current object to the result
result.push(theObjItem.id);
}
}
console.log(result);
You can simply use lodash library as it has many inbuilt functions that can reduce coding on server side.
npm i --save lodash
_.map(arr, 'id');
Result will be [367790083, 41370460, 41370460]
Related
This question already has answers here:
Find all values by specific key in a deep nested object
(11 answers)
Closed 10 months ago.
I have this JSON array tree that can include any number of nested arrays:
const namesArrayTree = [
{
"name": "Peter"
},
{
"name": "folder1",
"isArray": true,
"namesArray": [
{
"name": "Paul"
},
{
"name": "folder2",
"isArray": true,
"namesArray": [
{
"name": "Mary"
},
{
"name": "John"
}
]
}
]
},
{
"name": "Mark"
}
]
I need to transform it to a flat array including only the names:
const namesArrayFlat = [ "Peter", "Paul", "Mary", "John", "Mark" ]
So I'm using this code to do the transformation:
const namesArrayTree = [
{
"name": "Peter"
},
{
"name": "folder1",
"isArray": true,
"namesArray": [
{
"name": "Paul"
},
{
"name": "folder2",
"isArray": true,
"namesArray": [
{
"name": "Mary"
},
{
"name": "John"
}
]
}
]
},
{
"name": "Mark"
}
] ;
function getNamesList(item) {
let name = item.name;
let isArray = item.isArray;
if (isArray) {
name = item.namesArray.map(getNamesList).join("\r\n");
}
return name;
}
const namesList = namesArrayTree.map(getNamesList).join("\r\n");
const namesArrayFlat = namesList.split("\r\n");
console.log(namesArrayFlat)
The code works well, but I would like to get rid of the extra steps to create a list with the names using join.("\r\n") and then convert to array using split("\r\n").
That is, I would like to reduce the code by removing the following:
function getNamesList(item) {
let name = item.name;
let isArray = item.isArray;
if (isArray) {
/* remove code to join by "\r\n" */
name = item.namesArray.map(getNamesList)
}
return name;
}
/* remove code to create "namesList" constant and remove code to join by "\r\n") */
const namesArrayFlat = namesArrayTree.map(getNamesList)
console.log(namesArrayFlat)
(The above code still returns a tree nested arrays structure)
Any ideas about how to get rid of the extra code? also any suggestions about how to improve the code would be great, thanks!
function getNamesList(item) {
return item.isArray ? item.namesArray.map(getNamesList) : item.name
}
const names = namesArrayTree.map(getNamesList).flat(Infinity)
console.log(names)
You can achieve this with an array reducer as follows:
const namesArray = [
{
"name": "Peter"
},
{
"name": "folder1",
"isArray": true,
"namesArray": [
{
"name": "Paul"
},
{
"name": "folder2",
"isArray": true,
"namesArray": [
{
"name": "Mary"
},
{
"name": "John"
}
]
}
]
},
{
"name": "Mark"
}
] ;
function reduceNamesList(list, item) {
if (item.isArray) {
return item.namesArray.reduce(reduceNamesList, list);
}
list.push(item.name)
return list
}
const namesList = namesArray.reduce(reduceNamesList, [])
console.log(namesList)
I have this nested object (json):
const json = {
"application": {
"App1": {
"cats": [
1
]
},
"App2": {
"cats": [
3
]
},
"App3": {
"cats": [
1,
2
]
}
},
"categories": {
"1": {
"name": "FirstCategory"
},
"2": {
"name": "SecondCategory"
},
"3": {
"name": "ThirdCategory"
}
}
};
This object has two main properties: application and categories.
I want to map over application's cats array and get name property of each element of cats array.
So the final result should look like:
{
"App1": "FirstCategory",
"App2": "ThirdCategory",
"App3": "FirstCategory, ThirdCategory"
}
I have tried to use map function, but the main difficulty is that inside applicaiton property cats is array (can have multiple values). So the code below didn't work:
Object.values(json.application).map(val => {
Object.keys(json.categories).map(key => {
//print something
});
});
You can use Array.reduce for an elegant solution.
const json = {
"application": {
"App1": {
"cats": [
1
]
},
"App2": {
"cats": [
3
]
},
"App3": {
"cats": [
1,
2
]
}
},
"categories": {
"1": {
"name": "FirstCategory"
},
"2": {
"name": "SecondCategory"
},
"3": {
"name": "ThirdCategory"
}
}
};
//Getting Application object
const application = json.application
//Getting Categories object
const categories = json.categories
//initializing reduce with a blank object and pushing all the keys of the application object
//Looping over keys of application object
const requiredOutput = Object.keys(application).reduce((out, appKey) => {
//Setting value based on categories name
out[appKey] = application[appKey].cats.map(id => categories[id].name)
return out
}, {})
console.log(requiredOutput)
PS: You can refer this gist for safe reading from a nested object.
Try it with this.
for(let val in json.application){
json.application[val] = json.application[val].cats.map(cat => json.categories[cat].name).join(",")
}
const result = Object.keys(json.application).reduce((a,key) => {
a[key] = json.application[key].cats
.map(cat => json.categories[cat].name)
.join(", ")
return a;
}, {})
loop over keys of application
for each key loop over car, and for each cat return string value from category
join list of cat strings
My target is if the id from digital_assets and products matches then get the value of URL fro digital_assets and ProductName from products object. I'm able to traverse through the object and get the values of digital_assets and products but need some help to compare these two objects based on IDs to get the value of URL and ProductName. Below is what I've done so far.
var data = [{
"digital_assets": [{
"id": "AA001",
"url": "https://via.placeholder.com/150"
},{
"id": "AA002",
"url": "https://via.placeholder.com/150"
}]
}, {
"products": [{
"id": ["BB001", "AA001"],
"ProductName": "PROD 485"
},{
"id": ["BB002", "AA002"],
"ProductName": "PROD 555"
}]
}
];
$.each(data, function () {
var data = this;
//console.log(data);
$.each(data.digital_assets, function () {
var dAssets = this,
id = dAssets['id'];
// console.log(id);
});
$.each(data.products, function () {
var proData = this,
prod_id = proData['id'];
// console.log(prod_id);
$.each(prod_id, function () {
var arr_id = this;
console.log(arr_id);
});
});
});
Do I need to create new arrays and push the values into the new arrays? Then concat() these array to one. ? Bit lost any help will be appreciated.
Here is one way you can do this via Array.reduce, Array.includes, Object.entries and Array.forEach:
var data = [{ "digital_assets": [{ "id": "AA001", "url": "https://via.placeholder.com/150" }, { "id": "AA002", "url": "https://via.placeholder.com/150" } ] }, { "products": [{ "id": ["BB001", "AA001"], "ProductName": "PROD 485" }, { "id": ["BB002", "AA002"], "ProductName": "PROD 555" } ] } ]
const result = data.reduce((r,c) => {
Object.entries(c).forEach(([k,v]) =>
k == 'digital_assets'
? v.forEach(({id, url}) => r[id] = ({ id, url }))
: v.forEach(x => Object.keys(r).forEach(k => x.id.includes(k)
? r[k].ProductName = x.ProductName
: null))
)
return r
}, {})
console.log(Object.values(result))
You can use Array.prototype.find, Array.prototype.includes and Array.prototype.map to achieve this very gracefully.
let data = [
{
"digital_assets": [
{
"id": "AA001",
"url": "https://via.placeholder.com/150"
},
{
"id": "AA002",
"url": "https://via.placeholder.com/150"
}
]
},
{
"products": [
{
"id": ["BB001", "AA001"],
"ProductName": "PROD 485"
},
{
"id": ["BB002","AA002"],
"ProductName": "PROD 555"
}
]
}
];
// Find the 'digital_assets' array
let assets = data.find(d => d['digital_assets'])['digital_assets'];
// Find the 'products' array
let products = data.find(d => d['products'])['products'];
// Return an array of composed asset objects
let details = assets.map(a => {
return {
id : a.id,
url : a.url
name : products.find(p => p.id.includes(a.id)).ProductName
};
});
console.log(details);
changed answer to fit your needs:
var data = [
{
"digital_assets": [
{
"id": "AA001",
"url": "https://via.placeholder.com/150"
},
{
"id": "AA002",
"url": "https://via.placeholder.com/150"
}
]
},
{
"products": [
{
"id": ["BB001", "AA001"],
"ProductName": "PROD 485"
},
{
"id": ["BB002","AA002"],
"ProductName": "PROD 555"
}
]
}
]
let matchingIds = [];
let data_assetsObject = data.find(element => {
return Object.keys(element).includes("digital_assets")
})
let productsObject = data.find(element => {
return Object.keys(element).includes("products")
})
data_assetsObject["digital_assets"].forEach(da => {
productsObject["products"].forEach(product => {
if (product.id.includes(da.id)){
matchingIds.push({
url: da.url,
productName: product.ProductName
})
}
})
})
console.log(matchingIds);
working fiddle: https://jsfiddle.net/z2ak1fvs/3/
Hope that helped. If you dont want to use a new array, you could also store the respective data within the element you are looping through.
Edit:
I think i know why i got downvoted. My example works by making data an object, not an array. changed the snippet to show this more clearly.
Why is data an array anyway? Is there any reason for this or can you just transform it to an object?
Edit nr2:
changed the code to meet the expectations, as i understood them according to your comments. it now uses your data structure and no matter whats in data, you can now search for the objects containing the digital_assets / products property.
cheers
https://jsfiddle.net/2b1zutvx/
using map.
var myobj = data[0].digital_assets.map(function(x) {
return {
id: x.id,
url: x.url,
ProductName: data[1].products.filter(f => f.id.indexOf(x.id) > -1).map(m => m.ProductName)
};
});
I want to remove a duplicate array from the response on the basis of the attribute value. If the attribute_value data match with other array attribute value then other should be removed.
The logic is very simple. check duplicate attribute_value in each array and remove duplicate array and return
In response. now you can see the attribute value = 1 is thrice
and attribute value = 2 is twice
How do i compare and remove whole array if I see attribute value duplicate?
I tried with filter method which seems not working. Please help.
for(var j=0; j<social_post_link.length; j++){
newFilterarray = social_post_link[j].activity_attributes[0].attribute_value.filter(function(item, index) {
if (social_post_link[j].activity_attributes[0].attribute_value.indexOf(item) == index){
return social_post_link;
}
});
}
Response
[
{
"id": "484822",
"activity_attributes": [
{
"id": "868117",
"activity_id": "484822",
"attribute_name": "position",
"attribute_value": "1",
}
]
},
{
"id": "484884",
"activity_attributes": [
{
"id": "868175",
"activity_id": "484884",
"attribute_name": "position",
"attribute_value": "1",
}
]
},
{
"id": "484888",
"activity_attributes": [
{
"id": "868182",
"activity_id": "484888",
"attribute_name": "position",
"attribute_value": "1",
}
]
},
{
"id": "484823",
"activity_attributes": [
{
"id": "868120",
"activity_id": "484823",
"attribute_name": "position",
"attribute_value": "2",
}
]
},
{
"id": "484975",
"activity_attributes": [
{
"id": "868344",
"attribute_name": "position",
"attribute_value": "2",
}
]
},
{
"id": "484891",
"activity_attributes": [
{
"id": "868189",
"attribute_name": "position",
"attribute_value": "3",
}
]
},
{
"id": "484903",
"activity_attributes": [
{
"id": "868200",
"attribute_name": "position",
"attribute_value": "4",
},
]
}
]
Desired output
[
{
"id": "484822",
"activity_attributes": [
{
"id": "868117",
"activity_id": "484822",
"attribute_name": "position",
"attribute_value": "1",
}
]
},
{
"id": "484823",
"activity_attributes": [
{
"id": "868120",
"activity_id": "484823",
"attribute_name": "position",
"attribute_value": "2",
}
]
},
{
"id": "484891",
"activity_attributes": [
{
"id": "868189",
"attribute_name": "position",
"attribute_value": "3",
}
]
},
{
"id": "484903",
"activity_attributes": [
{
"id": "868200",
"attribute_name": "position",
"attribute_value": "4",
},
]
}
]
You can probably use the lodash utility uniqBy,
where iteratee is a function that returns the value you want to compare against.
In your case, it would probably look like the following:
const uniqueLinks = _.uniqBy(social_post_link, item =>
item.activity_attributes[0].attribute_value
)
Edit:
Here is a vanilla JS function that will accomplish the same.
const filterByIteratee = (array, iteratee) => {
// Empty object to store attributes as we encounter them
const previousAttributeNames = {
}
return array.filter(item => {
// Get the right value
const itemValue = iteratee(item)
// Check if we have already stored this item
if (previousAttributeNames.hasOwnProperty(itemValue)) return false
else {
// Store the item so next time we encounter it we filter it out
previousAttributeNames[itemValue] = true
return true
}
})
}
It will loop through an array, store its identifier by some function, and return only the first instance of each item.
Use it the same way:
const uniqueLinks = filterByIteratee(social_post_link, item =>
item.activity_attributes[0].attribute_value
)
This is probably not the best performing solution. but it works for your requirements.
var resultArray = [];
for (var i = 0; i < social_post_link.length; i++) {
var currentSocialLink = social_post_link[i];
for (var j = 0; j < currentSocialLink.activity_attributes.length; j++) {
if (!resultArray.some(val =>
val.activity_attributes.some(activity =>
activity.attribute_value === currentSocialLink.activity_attributes[j].attribute_value))) {
resultArray.push(currentSocialLink);
}
}
}
function removeDuplicates(myArr, prop) { // removes duplicate objects from array
return myArr.filter((obj, pos, arr) => {
return arr.map(mapObj => mapObj[prop]).indexOf(obj[prop]) === pos;
});
};
I found this function not too long ago which removes duplicate objects from an array. Pass it the array and the property you wish to not be duplicated.
Sorry if this has been asked before. I have the JSON structure like:
{"data":[
{"Date":"03/04/2016","Key":"A","Values":"123"},
{"Date":"04/04/2016","Key":"A","Values":"456"},
{"Date":"03/04/2016","Key":"B","Values":"789"},
{"Date":"04/04/2016","Key":"B","Values":"012"}
]}
I want to change this to a different format which is basically grouped by Key and combines rest of the field in Values
{"Result":[
{
"Key":"A"
"Values":[["03/04/2016","123"], ["04/04/2016","456"]]
},
{"Key":"B"
"Values":[["03/04/2016","789"]},["04/04/2016","012"]]
}
]}
I want to do this javascript/html
You could iterate and build a new object if not exist.
var object = { "data": [{ "Date": "03/04/2016", "Key": "A", "Values": "123" }, { "Date": "04/04/2016", "Key": "A", "Values": "456" }, { "Date": "03/04/2016", "Key": "B", "Values": "789" }, { "Date": "04/04/2016", "Key": "B", "Values": "012" }], result: [] };
object.data.forEach(function (a) {
if (!this[a.Key]) {
this[a.Key] = { Key: a.Key, Values: [] };
object.result.push(this[a.Key]);
}
this[a.Key].Values.push([a.Date, a.Values]);
}, Object.create(null));
console.log(object);
I think this can be a better answer (but Nina's answer is the match for your problem terms) if items of data array have different properties and you don't want to change input data.
var raw = {"data":[
{"Date":"03/04/2016","Key":"A","Values":"123"},
{"Date":"04/04/2016","Key":"A","Values":"456"},
{"Date":"03/04/2016","Key":"B","Values":"789"},
{"Date":"04/04/2016","Key":"B","Values":"012"}
]};
var result = new Map;
raw.data.forEach(entry => {
var key = entry.Key;
if (this[key])
return this[key].push(getClonedData(entry));
this[key] = [getClonedData(entry)];
result.set(key, {
Key: key,
Values: this[key]
})
}, Object.create(null));
var filtered = {
result: [...result.values()]
}
console.log(filtered);
function getClonedData(entry) {
data = Object.assign({}, entry);
delete data.Key;
return data;
}