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Group array of objects with a specific key value pushed first

Given the following Array of Objects:
[
{
"teamFK": 8650,
"code": "yellow_cards",
"typeId": 554,
"value": "5",
"side": "home"
},
{
"teamFK": 8650,
"code": "goals",
"typeId": 554,
"value": "1",
"side": "home"
},
{
"teamFK": 8990,
"code": "yellow_cards",
"typeId": 555,
"value": "2",
"side": "away"
},
{
"teamFK": 8990,
"code": "goals",
"typeId": 555,
"value": "0",
"side": "away"
}
]
I would like to group this data by code and get this result:
{
"stats": [
{
"name": "yellow_cards",
"stats": ["5","2"]
},
{
"name": "goals",
"stats": ["2","0"]
}
]
}
What I've done is the following which works but I want to make sure that the alway the stat with "side":"home" always pushed first into the array "stats": []:
const groupedStats = Object.entries(
query.reduce((acc, { typeId, value, code, side }) => {
if (!acc[code]) {
acc[code] = [];
}
acc[code].push(value);
return acc;
}, {}),
).map(([name, stats]) => ({ name, stats }));

My approach is sort it first by side using Array.sort() and then looping through the objects and adding it to stats
i created a const match to find if there is a match already so i dont have to add the name and value again basically if its not a match i'll add it to the stats array and if its a match then i'll just update the current index
const objs = [
{
teamFK: 8650,
code: "yellow_cards",
typeId: 554,
value: "5",
side: "home",
},
{
teamFK: 8650,
code: "goals",
typeId: 554,
value: "1",
side: "away",
},
{
teamFK: 8990,
code: "yellow_cards",
typeId: 555,
value: "2",
side: "away",
},
{
teamFK: 8990,
code: "goals",
typeId: 555,
value: "0",
side: "home",
},
];
let stats = [];
const transformedObj = objs
.sort((a, b) => {
if (a.side > b.side) {
return -1;
}
if (a.side < b.side) {
return 1;
}
return 0;
})
.forEach((obj) => {
const match = stats.find((stat) => stat.name === obj.code);
const statsIndex = stats.findIndex((stat) => stat.name === obj.code);
if (!match) {
stats = [...stats, { name: obj.code, value: [obj.value] }];
} else {
stats[statsIndex] = {
name: stats[statsIndex].name,
value: [...stats[statsIndex].value, obj.value],
};
}
});
console.log(stats);

You can sort array and use key grouping approach:
const data = [{"teamFK": 8650,"code": "yellow_cards","typeId": 554,"value": "5","side": "home"},{"teamFK": 8650,"code": "goals","typeId": 554,"value": "1","side": "home"},{"teamFK": 8990,"code": "yellow_cards","typeId": 555,"value": "2","side": "away"},{"teamFK": 8990,"code": "goals","typeId": 555,"value": "0","side": "away"}];
const groups = data
.sort(({ side: a }, { side: b }) => b.localeCompare(a))
.reduce((acc, { code, value }) => {
acc[code] ??= { name: code, stats: [] };
acc[code]['stats'].push(value);
return acc;
}, {});
const result = { stats: Object.values(groups) };
console.log(result);
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moving a key value pair out of an array

I am trying to move everything in the Array Results outside and into the original object
this is the object
{
"Name": "John",
"Results": [
{
"Type": "DB",
"Immediate_Action": "No",
}
]
}
It should look like this
{
"Name": "John",
"Type": "DB",
"Immediate_Action": "No",
}
What I have so far is this
const mapOscarResults = ({ data }) => {
return data.map(entry => {
let mapped = {...entry};
entry.Results.forEach(key => {
let Type = mapped[key.Type]
if (mapped[key]) {
mapped[key].push(entry.Results[key]);
} else {
mapped[key] = [entry.Results[key]];
}
});
return mapped;
});
};

You can simply spread the Results array into an Object.assign() call.
const input = { "Name": "John", "Results": [{ "Type": "DB", "Immediate_Action": "No", }, { "Another": "value" }] };
const { Results, ...refactored } = input;
Object.assign(refactored, ...Results);
console.log(refactored)

This code works for your example:
const { Results: results, ...rest } = {
"Name": "John",
"Results": [
{
"Type": "DB",
"Immediate_Action": "No",
}
]
}
const res = {...rest, ...results.reduce((prev, curr) => ({
...prev,
...curr
}), {})}
console.log(res)
But I don't know what you expect when the Results array has more than one element.
In that condition, if this code does not fill your needs, ask me to change it.

however, it will join first Result with index 0, you can expand it
const data = {
"Name": "John",
"Results": [
{
"Type": "DB",
"Immediate_Action": "No",
}
]
}
const mapOscarResults = (data) => {
for (let i in Object.keys(data)){
if (Array.isArray(data[Object.keys(data)[i]])){
newKey = data[Object.keys(data)[i]][0]
data = {... data, ...newKey}
delete data[Object.keys(data)[i]]
}
}
return data
};
console.log(mapOscarResults(data))

array to nested array conversion

my backend service send me list of node as an array. but I need is, each next node is value of its previous node(SEE EXAMPLE). I want whole list as nested object in singe object.
WHAT I HAVE:
[
{
"nodeId": 1,
},
{
"nodeId": 3,
},
{
"nodeId": 16,
}
]
WHAT I NEED:
[
{
"nodeId": 1,
"staticChild": [
{
"nodeId": 3,
"staticChild": [
{
"nodeId": 16,
}
]
}
]
}
]

You could reduce the array from the right side and build a new object with a staticChild property.
var array = [{ nodeId: 1 }, { nodeId: 3 }, { nodeId: 16 }],
result = array.reduceRight((a, b) => ({ ...b, staticChild: [a] }));
console.log(result);
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Based on the input / output you provided, you can use a recursive funtion like :
const data = [{
nodeId: 1
},
{
nodeId: 3
},
{
nodeId: 16
}
];
const transform = data => {
const [node, ...rest] = data;
if (rest.length > 0) {
return {
...node,
staticChild: [transform(rest)]
};
} else {
return {
...node,
hasChildren: false
};
}
};
const result = transform(data);
console.log(result);

At first reverse the array and the make an iteration over the revered array using reduce() to make your desire format.
let data = [{"nodeId": 1},{"nodeId": 3},{"nodeId": 16}]
data = data.reverse().reduce((old, cur) => {
if (!old.length) {
old = [cur]
} else {
cur['staticChild'] = old
old = [cur]
}
return old
}, [])
console.log(data)

You can use the reduceRight() array method to perform the transformation.
const data = [{
"nodeId": 1,
},
{
"nodeId": 3,
},
{
"nodeId": 16,
}
]
const nested = data.reduceRight((acc, item) => {
return [ { ...item, staticChild: acc } ]
}, []);
console.log(nested);
Or more succinctly:
const nested = data.reduceRight((acc, item) => [ { ...item, staticChild: acc } ],[]);

Merge two json arrays

I have to array i want to merge them in one array by same id. So every two array have same id should be merged
Case 1:
{
"id":1212,
"instructor":"william",
...
}
Case 2:
[
{
"id":1212,
"name":"accounting",
...
},
{
"id":1212,
"name":"finance",
...
}
]
I need the result to be :
{
"id": 1212,
"instructor": "william",
"Courses": [
{
"id":1212,
"name":"accounting",
...
},
{
"id":1212,
"name":"finance",
...
}
]
}

What you're asking isn't merging, but here is how you can do that.
const instructors = [{ "id":1212, "instructor":"william", }];
const courses = [
{ "id":1212, "name":"accounting" },
{ "id":1212, "name":"finance" }
];
const expected = [{ "id":1212, "instructor":"william", "courses": [
{ "id":1212, "name":"accounting" },
{ "id":1212, "name":"finance" }
]}];
const composed = instructors.map(ins => {
const ret = {...ins};
ret.courses = courses.filter(cou => cou.id === ins.id);
return ret;
});
console.log(composed);

var finArr;
var course = [];
use forEach loop javascript get all value in put your value instead of varid and varname
course.push({"id":varid,"name":varname});
finArr = {"id":variableId,"instructor":variablename,"Courses":course}

Build array from another array if some key are identical using JavaScript

I have an array of data. Some of the key in the array are same. I would like to create a new array based on the key and add the other data.
This is my array
var myObjOne = [
{
"name":"John",
"id":1,
"car":"maruti"
},
{
"name":"John",
"id":2,
"car":"wolks"
},
{
"name":"John",
"id":3,
"car":"bmw"
},
{
"name":"Peter",
"id":4,
"car":"alto"
},
{
"name":"Peter",
"id":5,
"car":"swift"
}
];
I would like to convert the array in to the below format.
var myObj = [
{
"name":"John",
"items": [
{ "id":1, "car":"maruti" },
{ "id":2, "car":"wolks" },
{ "id":3, "car":"bmw" }
]},
{
"name":"Peter",
"items": [
{ "id":4, "car":"alto" },
{ "id":5, "car":"swift" },
]
}
];
I am working on a node environment.

You can create an object using Array#reduce first which maps name with items, and then create the final array by looping over the intermediate map using a for...of loop:
var source = [{"name":"John","id":1,"car":"maruti"},{"name":"John","id":2,"car":"wolks"},{"name":"John","id":3,"car":"bmw"},{"name":"Peter","id":4,"cars":"alto"},{"name":"Peter","id":5,"cars":"swift"}];
const map = source.reduce((acc, {name, ...obj}) => {
if (!acc[name]) {
acc[name] = [];
}
acc[name].push(obj);
return acc;
}, {});
const result = [];
for (let[name, items] of Object.entries(map)) {
result.push({name, items});
}
console.log(result);

Array.reduce is at rescue.This method accepts an accumulator and current
item. Check in the accumulator if there exist an object where the value of name property is John or Peter
var myObjOne = [{
"name": "John",
"id": 1,
"car": "maruti"
},
{
"name": "John",
"id": 2,
"car": "wolks"
},
{
"name": "John",
"id": 3,
"car": "bmw"
},
{
"name": "Peter",
"id": 4,
"car": "alto"
},
{
"name": "Peter",
"id": 5,
"car": "swift"
}
];
var newObj = myObjOne.reduce(function(acc, curr, currIndex) {
// using findIndex to check if there exist an object
// where the value of the name property is John, Peter
// if it exist it will return the index else it will return -1
let ifNameExist = acc.findIndex(function(item) {
return item.name === curr.name;
})
// if -1 then create a object with name and item property and push
// it to the accumulator
if (ifNameExist === -1) {
let nameObj = {};
nameObj.name = curr.name;
nameObj.items = [];
nameObj.items.push({
id: curr.id,
car: curr.car
})
acc.push(nameObj)
} else {
// if such an object already exist then just update the item array
acc[ifNameExist].items.push({
id: curr.id,
car: curr.car
})
}
return acc;
}, []);
console.log(newObj)

Use .reduce to group by name, and use .find inside the reducer to find if the matching name has already been added:
const input=[{"name":"John","id":1,"car":"maruti"},{"name":"John","id":2,"car":"wolks"},{"name":"John","id":3,"car":"bmw"},{"name":"Peter","id":4,"cars":"alto"},{"name":"Peter","id":5,"cars":"swift"}]
const output = input.reduce((a, { name, ...item }) => {
const foundNameObj = a.find(nameObj => nameObj.name === name);
if (foundNameObj) foundNameObj.items.push(item);
else a.push({ name, items: [item] });
return a;
}, []);
console.log(output);