I have a data set of the following form
let data = [
{
"id": {
"primary": "A1"
},
"msg": 1
}, {
"id": {
"primary": "A1"
},
"msg": 2
}, {
"id": {
"primary": "B2"
},
"msg": 3
}
]
I would like to transform it to
newData = [
{
"id": {
"primary": "A1"
},
"items": [
{ "msg": 1 },
{ "msg": 2 }
]
},
{
"id": {
"primary": "B2"
},
"items": [
{ "msg": 3 }
]
}
]
I think the method is something like the following, but am not sure how to check against undefined values in this case.
let newData = [];
for (let i = 0; i < data.length; i++) {
if (newData[i]['id']['primary'] === data[i]['id']) newData.push(data[i]['id'])
else newData[i]['items'].push(data[i]['msg'])
}
How can I transform the original data set to merge entries with a matching primary id?
One option would be to use .reduce() to create a new array from the existing.
I've added comments to clarify.
let data = [ { "id": { "primary": "A1" }, "msg": 1 }, { "id": { "primary": "A1" }, "msg": 2 }, { "id": { "primary": "B2" }, "msg": 3 } ];
let result = data.reduce((out,item) => {
let {id, ...items} = item; //Separate the "id" and "everything else"
let existing = out.find(({id}) => id.primary == item.id.primary);
existing //have we seen this ID already?
? existing.items.push(items) //yes - add the items to it
: out.push({ id: {...id}, items: [items]}); //no - create it
return out;
}, []);
console.log(result);
A couple notes:
You may notice that I've set the ID using id: {...id}, despite the id already being an object. This is because using the existing id object would create a reference, whereas {...id} creates a shallow copy.
I haven't specified the msg property anywhere. Instead, any properties that aren't id will be added to the items list (example below).
let data = [ { "id": { "primary": "A1" }, "msg": 1, "otherStuff": "Hello World!" }, { "id": { "primary": "A1" }, "msg": 2, "AnotherThing": true }, { "id": { "primary": "B2" }, "msg": 3, "someOtherProperty": false } ];
let result = data.reduce((out,item) => {
let {id, ...items} = item;
let existing = out.find(({id}) => id.primary == item.id.primary);
existing
? existing.items.push(items)
: out.push({ id: {...id}, items: [items]});
return out;
}, []);
console.log(result);
That said, if you start to nest objects (other than ID), they will likely be included as references; ...items is only a shallow copy.
If such a case, consider something like JSON.parse(JSON.stringify(...)) for a deep copy. Be sure to read the link though; there are caveats.
You could also solve this in a concise way via the Array.reduce and ES6 destructuring:
let data = [ { "id": { "primary": "A1" }, "msg": 1 }, { "id": { "primary": "A1" }, "msg": 2 }, { "id": { "primary": "B2" }, "msg": 3 } ]
let result = data.reduce((r, {id, msg}) =>
((r[id.primary] = r[id.primary] || { id, items: [] }).items.push({msg}), r), {})
console.log(Object.values(result))
In more readable format it is:
let data = [ { "id": { "primary": "A1" }, "msg": 1 }, { "id": { "primary": "A1" }, "msg": 2 }, { "id": { "primary": "B2" }, "msg": 3 } ]
let result = data.reduce((r, {id, msg}) => {
r[id.primary] = (r[id.primary] || { id, items: [] })
r[id.primary].items.push({msg})
return r
}, {})
console.log(Object.values(result))
The idea is to group by the id.primary and then once the grouping is done simply get the values via Object.values
Notice that this is one pass solution where you do not have to per each iteration do an Array.find against the current accumulator.
Related
I am using Angular 13 and I have an array of objects like this:
[{
"name": "Operating System",
"checkedCount": 0,
"children": [{
"name": "Linux",
"value": "Redhat",
"checked": true
},
{
"name": "Windows",
"value": "Windows 10"
}
]
},
{
"name": "Software",
"checkedCount": 0,
"children": [{
"name": "Photoshop",
"value": "PS",
"checked": true
},
{
"name": "Dreamweaver",
"value": "DW"
},
{
"name": "Fireworks",
"value": "FW",
"checked": true
}
]
}
]
I would like to loop through the array, check if each object has a children array and it in turn has a checked property which is set to true, then I should update the checkedCount in the parent object. So, result should be like this:
[{
"name": "Operating System",
"checkedCount": 1,
"children": [{
"name": "Linux",
"value": "Redhat",
"checked": true
},
{
"name": "Windows",
"value": "Windows 10"
}
]
},
{
"name": "Software",
"checkedCount": 2,
"children": [{
"name": "Photoshop",
"value": "PS",
"checked": true
},
{
"name": "Dreamweaver",
"value": "DW"
},
{
"name": "Fireworks",
"value": "FW",
"checked": true
}
]
}
]
I tried to do it this way in angular, but this is in-efficient and results in an error saying this.allFilters[i].children[j] may be undefined. So, looking for an efficient manner to do this.
for(let j=0;i<this.allFilters[i].children.length; j++) {
if (Object.keys(this.allFilters[i].children[j]).length > 0) {
if (Object.prototype.hasOwnProperty.call(this.allFilters[i].children[j], 'checked')) {
if(this.allFilters[i].children[j].checked) {
this.allFilters[i].checkedCount++;
}
}
}
}
Use a nested for loop to check all the children. If checked is truthy, increment the count of the parent. You don't need to check if parent.children has any elements since if there are no elements the loop won't run anyways.
// minified data
const data = [{"name":"Operating System","checkedCount":0,"children":[{"name":"Linux","value":"Redhat","checked":!0},{"name":"Windows","value":"Windows 10"}]},{"name":"Software","checkedCount":0,"children":[{"name":"Photoshop","value":"PS","checked":!0},{"name":"Dreamweaver","value":"DW"},{"name":"Fireworks","value":"FW","checked":!0}]}];
for (const parent of data) {
for (const child of parent.children) {
if (child.checked) parent.checkedCount++;
}
}
console.log(data);
No need to complicate it like that, you just need to check checked property in children.
data.forEach((v) => {
v.children.forEach((child) => {
if (child.checked) {
v.checkedCount++;
}
});
});
Using filter + length on children array should do the job:
const data = [{"name":"Operating System","checkedCount":null,"children":[{"name":"Linux","value":"Redhat","checked":true},{"name":"Windows","value":"Windows 10"}]},{"name":"Software","checkedCount":null,"children":[{"name":"Photoshop","value":"PS","checked":true},{"name":"Dreamweaver","value":"DW"},{"name":"Fireworks","value":"FW","checked":true}]}];
data.forEach(itm => {
itm.checkedCount = itm.children?.filter(e => e.checked === true).length ?? 0;
});
console.log(input);
I would suggest going functional.
Using map
const children = arr.map(obj => obj.children);
const result = children.map((child, idx) => {
const checkedCount = child.filter(obj => obj.checked)?.length;
return {
...arr[idx],
checkedCount
};
});
console.log(result)
or using forEach
const result = [];
const children = arr.map(obj => obj.children);
children.forEach((child, idx) => {
const checkedCount = child.filter(obj => obj.checked)?.length;
result[idx] = {
...arr[idx],
checkedCount
};
});
console.log(result)
let data = {
"rec": [{
"id": "25837",
"contentId": "25838"
},
{
"id": "25839",
"contentId": "25838"
},
{
"id": "25838"
},
{
"id": "25636",
"contentId": "25837"
}, {
"id": "25640",
"contentId": "25839"
}
]
};
I have a javascript object which I have to manipulate to below format.
{
"childern": [{
"id": "25838",
"childern": [{
"id": "25837",
"contentId": "25838",
"childern": [{
"id": "25636",
"contentId": "25837"
}]
},
{
"id": "25839",
"contentId": "25838",
"childern": [{
"id": "25640",
"contentId": "25839"
}]
}
]
}]
}
If any object dont have contentId it should be at parent level. then all the objects having contentId same as parent id should be at its child level and so on.
I have created a fiddle here but logic is not completed. Any idea or reference to achieve this.
You could create recursive function with reduce method to get the desired result.
let data = {"rec":[{"id":"25837","contentId":"25838"},{"id":"25839","contentId":"25838"},{"id":"25838"},{"id":"25636","contentId":"25837"},{"id":"25640","contentId":"25839"}]}
function nest(data, pid) {
return data.reduce((r, e) => {
if (pid == e.contentId) {
const obj = { ...e }
const children = nest(data, e.id);
if (children.length) obj.children = children
r.push(obj)
}
return r;
}, [])
}
const result = nest(data.rec);
console.log(result[0])
I have two arrays of object, the first array (printerChart, around 80 elements) is made of the following type of objects:
[{
printerBrand: 'Mutoh',
printerModel: 'VJ 1204G',
headsBrand: 'Epson',
headType: '',
compatibilty: [
'EDX',
'DT8',
'DT8-Pro',
'ECH',
],
},
....
]
The second array (items, around 500 elements) is made of the following type of objects:
[
{
"customData": {
"brand": {
"value": {
"type": "string",
"content": "hp"
},
"key": "brand"
},
"printer": {
"value": {
"type": "string",
"content": "c4280"
},
"key": "printer"
}
},
"name": "DT8 XLXL",
"image": {
"id": "zLaDHrgbarhFSnXAK",
"url": "https://xxxxxxx.net/images/xxxxxx.jpg"
},
"brandId": "xxxxx",
"companyId": "xxxx",
"createdAt": "2018-03-26T14:39:47.326Z",
"updatedAt": "2018-04-09T14:31:38.169Z",
"points": 60,
"id": "dq2Zezwm4nHr8FhEN"
},
...
]
What I want to do is to iterate via the second array and, if the part of the name of an item (i.e. DT8) is included in an element of the array 'compatibility' of the first array, I would like to include a new properties to it from the element of the first array: printerBrand. I have tried but somehow the iteration doesn't take place correctly. This is what I tried:
items.forEach((item) => {
printerChart.forEach((printer) => {
if (printer.compatibilty.some(compatibleElem => (
item.name.includes(compatibleElem)))) {
item.printerBrand = printer.printerBrand;
} else {
item.printerBrand = '';
}
});
});
What am I doing wrong?
You do
items.items.forEach(...)
Shouldn't you be doing
items.forEach(...)
?
I suggest to initialize item.printerBrand with an empty string and use a nested approach of some for getting a brand and to exit the loops, if found.
This prevents to get an empty string even if there is a brand to assign.
items.forEach((item) => {
item.printerBrand = '';
printerChart.some(printer => {
if (printer.compatibilty.some(compatibleElem => item.name.includes(compatibleElem))) {
item.printerBrand = printer.printerBrand;
return true;
}
});
});
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.
I would like to transform the following JSON into another structure.
The source JSON:
values = array with objects wich needs to filtered by action === 'commented'
comment = object with the comment, n Tasks and n Comments
Comments can have endless more Comments and Tasks
{
"values": [
{
"action": "COMMENTED",
"comment": {
"text": "comment text",
"comments": [
{
"text": "reply text",
"comments": [],
"tasks": []
}
],
"tasks": [
{
"text": "task text",
"state": "RESOLVED"
}
]
}
}
]
}
The Target JSON:
Array(s) with Objects
each comment or tasks is a "children" (recursive!)
[
{
"text": "comment text",
"children": [
{
"text": "reply text",
"type": "comment"
},
{
"text": "task text",
"state": "RESOLVED"
}
]
}
]
Ive started with:
data = data.values.filter((e)=>{
return e.action === 'COMMENTED';
}).map((e)=>{
// hmmm recursion needed, how to solve?
});
data = data.values.filter(e => e.action === 'COMMENTED')
.map(function recursion({comment}){
return {
text: comment.text,
children: [...comment.comments.map(recursion), ...comment.tasks];
};
});
I ended up with:
let data = response.data.values
.filter(e => e.action === 'COMMENTED')
.map(function e({comment, commentAnchor}) {
return {
commentAnchor,
text: comment.text,
children: [...comment.comments.map(function recursion(comment) {
if (typeof comment === 'undefined') {
return {};
}
let children = [];
if (comment.comments) {
children.push(...comment.comments.map(recursion));
}
if (comment.tasks) {
children.push(...comment.tasks);
}
let _return = {
...comment,
text: comment.text
};
_return.children = children;
return _return;
}), ...comment.tasks]
}
});