Ramda to loop over array - javascript

Loop may be the wrong term, but it kind of describes what I am attempting.
I want to give structure to flat data, but I also need to keep track of the array it came from.
Basically my rules are (per array):
If level 1 exists- give it the name of the item, and a typechild array. EACH time a level 1 appears (even in the same array) it should create a new entry.
Inside typechild, put the any items with level >1
If NO level 1 exists- give it the name of the item, and a typechild array.
My code below is almost there, with the exception that it should create an array EVERYTIME it sees a level 1. My example will make sense:
Input data
[
{
"title": "Test 1",
"type": [{
"name": "Animal",
"level": 1
},
{
"name": "Food",
"level": 1
},
{
"name": "Chicken",
"level": 3
}
]
},
{
"title": "Test 2",
"type": [{
"name": "Foo",
"level": 2
}]
}
]
Note: Animal and Food are both LEVEL 1 items. So it should create two ARRAYS like so...
Desired output
[
{
name: "Animal",
typechild: [
{
level: 2,
name: "Chicken"
}
]
},
{
name: "Food",
typechild: [
{
level: 2,
name: "Chicken"
}
]
},
{
name: "NoName",
typechild: [
{
level: 2,
name: "Foo"
}
]
}
]
Ramda attempt (try here: https://dpaste.de/JQHw):
const levelEq = (n) => pipe(prop('level'), equals(n));
const topLevel = pipe(prop('type'), find(levelEq(1)));
const topLevelName = pipe(topLevel, propOr('NoName', 'name'));
const extract2ndLevel = pipe(pluck('type'), flatten, filter(levelEq(2)));
const convert = pipe(
groupBy(topLevelName),
map(extract2ndLevel),
map(uniq),
toPairs,
map(zipObj(['name', 'typechild']))
);

Something like this?
var output = [{
"name": "Animal",
"typechild": [{
"name": "Chicken",
"level": 3
}, {
"name": "Dog",
"level": 2
}]
}, {
"name": "Food",
"typechild": [{
"name": "Chicken",
"level": 3
}]
}, {
"name": "No name",
"typechild": [{
"name": "Foo",
"level": 2
}, {
"name": "Baz",
"level": 2
}]
}]
let out = {},
typechild = {},
k;
const data = [{
"title": "Test 1",
"type": [{
"name": "Animal",
"level": 1
}, {
"name": "Food",
"level": 1
}, {
"name": "Chicken",
"level": 3
}]
}, {
"title": "Test 2",
"type": [{
"name": "Foo",
"level": 2
}]
}, {
"title": "Test 3",
"type": [{
"name": "Baz",
"level": 2
}]
}, {
"title": "Test 4",
"type": [{
"name": "Animal",
"level": 1
}, {
"name": "Dog",
"level": 2
}]
}]
data.forEach((node) => {
k = false;
typechild[node.title] = [];
node.type && node.type.forEach((t, i) => {
if (t.level == 1) {
k = true;
!out[t.name] ? out[t.name] = {
name: t.name,
typechild: typechild[node.title]
} : out[t.name].typechild = out[t.name].typechild.concat(typechild[node.title]);
} else {
typechild[node.title].push(t);
}
if (i == node.type.length - 1 && !k && typechild[node.title].length) {
out['No name'] = out['No name'] || {
name: 'No name',
typechild: []
};
out['No name'].typechild = out['No name'].typechild.concat(typechild[node.title]);
}
});
});
console.log(JSON.stringify(Object.values(out)));

Related

How can I inner join with two object arrays in JavaScript?

I need inner join with two array in javascript like this:
array1 =
[
{
"id": 1,
"name": "Tufan"
},
{
"id": 2,
"name": "Batuhan"
},
{
"id": 3,
"name": "Hasan"
}
]
array2 =
[
{
"name": "yyy",
"externalid": "1",
"value": "Asd"
},
{
"name": "aaaa"
"externalid": "2",
"value": "ttt"
}
]
expectedArray =
[
{
"id": 1,
"name": "Tufan",
"externalid": "1",
"value": "Asd"
},
{
"id": 2,
"name": "Batuhan",
"externalid": "2",
"value": "ttt"
}
]
rules:
on: array2.externalid = array1.id
select: array1.id, array1.name, array2.externalid, array2.value
My approach:
array1.filter(e => array2.some(f => f.externalid == e.id));
// I need help for continue
How can I make this?
Doesn't matter information: I use ES5 and pure javascript
You can do it like this:
const res = array2.map((item) => {
const related = array1.find((el) => el.id == item.externalid);
return { ...item, ...related };
});
Using a map to loop over the array2 and a find to get the array1 relative.

Map new object from two objects array angular typescript baesed on id

I have something like this
export class Question {
id: string;
title: string;
description: string;
answers: Answer[];
}
export class Answer {
id: string;
text: string;
questionId: string;
}
and I have two object like this
answers = [
{
"id": 1,
"text": "some comment1",
"questionId": 1
},
{
"id": 2,
"text": "some comment2",
"questionId": 3
},
{
"id": 3,
"text": "some comment3",
"questionId": 3
}
];
questions = [
{
"id": 1,
"title": "Name1",
"description": "typicode1"
},
{
"id": 2,
"title": "Name2",
"description": "typicode2"
},
{
"id": 3,
"title": "Name3",
"description": "typicode3"
}
];
questionsAndAnswers: Question[];
Now i need to map answer to correct question on property answers
My new questionsAndAnswers should look like this
questionsAndAnswers = [{
id: 1,
title: Name1,
description: typicode1;
answers: [{
"id": 1,
"text": "some comment1",
"questionId": 1
}]
},
{
id: 2,
title: Name2,
description: typicode2;
answers: []
},
{
id: 3,
title: Name3,
description: typicode3;
answers: [{
"id": 2,
"text": "some comment2",
"questionId": 3
},
{
"id": 3,
"text": "some comment3",
"questionId": 3
}]
}
];
You could try use Array reduce with filter function. Try the following
var questions = [ { "id": 1, "title": "Name1", "description": "typicode1" }, { "id": 2, "title": "Name2", "description": "typicode2" }, { "id": 3, "title": "Name3", "description": "typicode3" } ];
var answers = [ { "id": 1, "text": "some comment1", "questionId": 1 }, { "id": 2, "text": "some comment2", "questionId": 3 }, { "id": 3, "text": "some comment3", "questionId": 3 } ];
var questionsAndAnswers = questions.reduce((acc, curr, index) => {
acc[index] = curr;
acc[index].answers = answers.filter(answer => answer.questionId === curr.id);
return acc;
}, []);
console.log(questionsAndAnswers);

Map Json Data to new key-value pair JavaScript object

I want to map one json data to a new javascript object like following. Here the json data is dynamic and can have more files with more users. The group information is new and it depends on parent-child information. Can anyone please help me out? Thank you for your time.
Before:
{
"userinfo": {
"/home/user/main/sub/info/1stfile.txt": {
"John": "something",
"Mike": "something",
"Merry": "something",
"Susan": "something"
},
"/home/user/main/info/2ndfile.txt": {
"Mulan": "something",
"James": "something"
},
"/home/user/main/info/3rdfile.txt": {
"Nancy": "something"
},
"/home/user/main/4thfile.txt": {
"Kamal": "something",
"Xian": "something",
"Mila": "something"
}
}
}
After:
{
"name": "main",
"children": [
{
"name": "1stfile",
"children": [
{
"name": "John",
"group": "1"
},
{
"name": "Mike",
"group": "1"
},
{
"name": "Merry",
"group": "1"
},
{
"name": "Susan",
"group": "1"
}
],
"group": 1
},
{
"name": "2ndfile",
"children": [
{
"name": "Mulan",
"group": 2
},
{
"name": "James",
"group": 2
}
],
"group": 2
},
{
"name": "3rdfile",
"children": [
{
"name": "Nancy",
"group": 3
}
],
"group": 3
},
{
"name": "4thfile",
"children": [
{
"name": "Kamal",
"group": 4
},
{
"name": "Xian",
"group": 4
},
{
"name": "Mila",
"group": 4
}
],
"group": 4
}
],
"group": 0
}
I was trying to build one block of parent-child by using following code
var jsonData = json["userinfo"];
var keys = Object.keys(jsonData);
console.log(keys);
let data = {};
for (var j = 0; j < keys.length; j++) {
let g = 1;
data[j] = { name: keys[j], group: g++ };
}
console.log(data);
Which is giving following output
{
0: {
"name": "/home/user/main/sub/info/1stfile.txt",
"group": 1
},
1: {
"name": "/home/user/main/info/2ndfile.txt",
"group": 1
},
2: {
"name": "/home/user/main/info/3rdfile.txt",
"group": 1
},
3: {
"name": "/home/user/main/4thfile.txt",
"group": 1
}
}
The value is assigning properly but is creating extra keys (0,1,2,3)!
Assuming you need something like this.
You can utilize Array.map() and Object.keys() function for your operation.
<script>
const beforeJSON = `{
"userinfo": {
"/home/user/main/sub/info/1stfile.txt": {
"John": "something",
"Mike": "something",
"Merry": "something",
"Susan": "something"
},
"/home/user/main/info/2ndfile.txt": {
"Mulan": "something",
"James": "something"
},
"/home/user/main/info/3rdfile.txt": {
"Nancy": "something"
},
"/home/user/main/4thfile.txt": {
"Kamal": "something",
"Xian": "something",
"Mila": "something"
}
}
}`
const before = JSON.parse(beforeJSON);
const filenames = Object.keys(before.userinfo);
const after = {
name: 'main',
children: [],
group: 0,
}
const children = filenames.map((filename, idx) => {
const innerChildren = Object.keys(before.userinfo[filename]).map((n) => ({
name: n,
group: idx + 1,
}))
return ({
name: filename,
children: innerChildren,
group: idx + 1,
});
})
after.children = children;
console.log(after);
</script>
Please format your code next time before posting another question.

Extract objects from nested array of objects

I have the following data that is an array of nested objects:
"categories": [
{
"id": 1,
"name": "Category 1",
"years": [
{ "id": 1, "name": "1" },
{ "id": 2, "name": "2" }
]
},
{
"id": 2,
"name": "Category 2",
"years": [
{ "id": 2, "name": "2" },
{ "id": 3, "name": "3" }
]
}
]
I want to extract unique years in a separate array (desired output):
[
{ "id": 1, "name": "1" },
{ "id": 2, "name": "2" },
{ "id": 3, "name": "3" },
]
When I map out the years, I'm getting an array of arrays, how should I extract the unique objects for years?
let years = categories.map( (c) => { return c.years })
You can use a Map to filter duplicate years from the array of values using id as the key, and reduce() on both categories and years using the map as the accumulator:
const categories = [{
"id": 1,
"name": "Category 1",
"years": [
{ "id": 1, "name": "1" },
{ "id": 2, "name": "2" }
]
},
{
"id": 2,
"name": "Category 2",
"years": [
{ "id": 2, "name": "2" },
{ "id": 3, "name": "3" }
]
}
];
const years = categories.reduce(
(map, category) => category.years.reduce(
(map, year) => map.set(year.id, year),
map
),
new Map()
);
console.log([...years.values()]);
You can use reduce and Map
let data = [{"id": 1,"name": "Category 1","years": [{ "id": 1, "name": "1" },{ "id": 2, "name": "2" }]},{"id": 2,"name": "Category 2","years": [{ "id": 2, "name": "2" },{ "id": 3, "name": "3" }]}]
let final = data.reduce((op,{years}) => {
years.forEach(({id, name}) => {
let key = id + '-' + name
op.set(key, op.get(key) || {id, name})
})
return op
},new Map())
console.log([...final.values()])

Filtering an array based on multiple arrays inputs

I have three arrays.
1. Existing viewers array - existingViewers
New viewers array - newViewers
Permitted Viewers array - permittedViewers
permittedViewers is used for rendering the drop-down. And I wish to filter the newViewers and existingViewers entries from the permittedViewers.
I am doing this as three steps. And I am afraid this is not the optimized way. Can someone suggest the ideal way of doing this?
The expected result is
[
{
"id": 4,
"name": "name4"
},
{
"id": 5,
"name": "name5"
},
{
"id": 6,
"name": "name6"
}
]
let existingViewers = [{
"viewerId": 1,
"name": "name1"
},
{
"viewerId": 2,
"name": "name2"
}
],
newViewers = [
{
"viewerId": 3,
"name": "name3"
}
],
permittedViewers = [{
"id": 1,
"name": "name1"
},
{
"id": 2,
"name": "name2"
},
{
"id": 3,
"name": "name3"
},
{
"id": 4,
"name": "name4"
},
{
"id": 5,
"name": "name5"
},
{
"id": 6,
"name": "name6"
}
]
let grouped = [...existingViewers, ...newViewers]
let viewerFilter = grouped.map(viewer => { return viewer.viewerId; });
let filteredPermittedViewers = permittedViewers.filter(viewer => !viewerFilter.includes(viewer.id));
console.log(filteredPermittedViewers)
I'd make a Set of the ids of the first two arrays, and then filter the third by whether the set includes the id. (Sets have O(1) lookup time)
let existingViewers=[{"viewerId":1,"name":"name1"},{"viewerId":2,"name":"name2"}],newViewers=[{"viewerId":3,"name":"name3"}],permittedViewers=[{"id":1,"name":"name1"},{"id":2,"name":"name2"},{"id":3,"name":"name3"},{"id":4,"name":"name4"},{"id":5,"name":"name5"},{"id":6,"name":"name6"}];
const ids = new Set([...existingViewers, ...newViewers].map(({ viewerId }) => viewerId));
const output = permittedViewers.filter(({ id }) => !ids.has(id));
console.log(output);
You can compress all three statements into a single statement -- just replace the variable name with the statement that creates it:
let existingViewers = [{
"viewerId": 1,
"name": "name1"
},
{
"viewerId": 2,
"name": "name2"
}
],
newViewers = [
{
"viewerId": 3,
"name": "name3"
}
],
permittedViewers = [{
"id": 1,
"name": "name1"
},
{
"id": 2,
"name": "name2"
},
{
"id": 3,
"name": "name3"
},
{
"id": 4,
"name": "name4"
},
{
"id": 5,
"name": "name5"
},
{
"id": 6,
"name": "name6"
}
]
let filteredPermittedViewers = permittedViewers.filter(viewer => ! [...existingViewers, ...newViewers].map(viewer => viewer.viewerId).includes(viewer.id));
console.log(filteredPermittedViewers)

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