We Keep Coding

Matching a variable with an object inside a nested array with JavaScript

I am trying to find a match inside this JSON array but I find it a bit complicated since it's a nested array of objects.
I'm not sure what I am doing entire wrong here:
The idea is that I have an array with a set of permissions and I want to return only the set of permissions that match the role:
var data = [{
"visitor": {
"static": ["page-one:visit", "home-page:visit", "login"]
}
}, {
"users": {
"static": ["posts:list", "posts:create", "users:getSelf", "home-page:visit", "dashboard-page:visit"]
}
}, {
"admin": {
"static": ["posts:list", "posts:create", "posts:edit", "posts:delete", "users:get", "users:getSelf", "home-page:visit", "dashboard-page:visit"]
}
}]
var role = "admin"
for(var x=0;x <data.length;x++){
if(role === data[x]){
console.log("OLE, we got a match!" + data[x])
}
}
For some reason I just can't find a match. I just wanna return the full object like:
"admin":{
"static": ["posts:list", "posts:create", "posts:edit", "posts:delete", "users:get", "users:getSelf", "home-page:visit", "dashboard-page:visit"]
}
Here is a JS Bin Link.

You could use the .find function like below:
data.find(function(x){ return Object.keys(x).indexOf(role) > -1; });
Given your role is the key of the object, you need to check if the object itself contains the role as a key, for this you'd use Object.keys(<object>).indexOf(role) where indexOf will return the value of -1 if it's not found and 0+ if found.
var data = [{"visitor":{"static":["page-one:visit","home-page:visit","login"]}},{"users":{"static":["posts:list","posts:create","users:getSelf","home-page:visit","dashboard-page:visit"]}},{"admin":{"static":["posts:list","posts:create","posts:edit","posts:delete","users:get","users:getSelf","home-page:visit","dashboard-page:visit"]}}]
var role = "admin"
var admins = data.find(function(x){ return Object.keys(x).indexOf(role) > -1; });
console.log(admins);
if you wanted to accommodate for an array of different roles, you can use the following, easy to follow example.
var data = [{"visitor":{"static":["page-one:visit","home-page:visit","login"]}},{"users":{"static":["posts:list","posts:create","users:getSelf","home-page:visit","dashboard-page:visit"]}},{"admin":{"static":["posts:list","posts:create","posts:edit","posts:delete","users:get","users:getSelf","home-page:visit","dashboard-page:visit"]}}]
var role = ["admin", "visitor"];
var admins = role.map(function(role) { return getObjectsForRole(role); })
function getObjectsForRole(role)
{
return data.find(function(x){
return Object.keys(x).indexOf(role) > -1;
});
}
console.log(admins);
The above is pretty much the same as before, but we're mapping (.map) each role and calling a function which contains our call to the .find function.

JSON Group by Name and then Display Latest Record

Using only JavaScript, I need to
Group by code.
Get latest modifieddate.
Display total grouped code as Count.
Starting JSON Result
[
{"ID":1,"code":"AAA","modifieddate":"2019-06-01","user":"John"},
{"ID":2,"code":"AAA","modifieddate":"2019-06-02","user":"Jane"},
{"ID":3,"code":"AAA","modifieddate":"2019-06-03","user":"Sue"},
{"ID":4,"code":"BBB","modifieddate":"2019-06-10","user":"Rick"},
{"ID":5,"code":"CCC","modifieddate":"2019-06-11","user":"Joe"}
]
Desired JSON Result set
[
{"ID":3,"code":"AAA","modifieddate":"2019-06-03","user":"Sue","Count":"3"},
{"ID":4,"code":"BBB","modifieddate":"2019-06-10","user":"Rick","Count":"1"},
{"ID":5,"code":"CCC","modifieddate":"2019-06-11","user":"Joe","Count":"1"}
]
Tried using reduce method.
I do not have access to modify the server side API code.
I am using Aurelia JS.

You can use Array.reduce to group the result set by each item's code property, incrementing Count as needed, then take the values from the accumulation object. Along the way, we perform a date comparison to determine which the most recent entry to include in the result.
const data = [ {"ID":1,"code":"AAA","modifieddate":"2019-06-01","user":"John"}, {"ID":2,"code":"AAA","modifieddate":"2019-06-02","user":"Jane"}, {"ID":3,"code":"AAA","modifieddate":"2019-06-03","user":"Sue"}, {"ID":4,"code":"BBB","modifieddate":"2019-06-10","user":"Rick"}, {"ID":5,"code":"CCC","modifieddate":"2019-06-11","user":"Joe"} ];
const result = Object.values(data.reduce((a, e) => {
if (!a[e.code]) {
a[e.code] = {...e, Count: 0};
}
if (Date.parse(e.modifieddate) > Date.parse(a[e.code].modifieddate)) {
a[e.code] = {...e, Count: a[e.code].Count};
}
a[e.code].Count++;
return a;
}, {}));
console.log(result);
By the way, this is just a plain JS array we're working with, not JSON.

This should get you:
let array = [
{"ID":1,"code":"AAA","modifieddate":"2019-06-01","user":"John"},
{"ID":2,"code":"AAA","modifieddate":"2019-06-02","user":"Jane"},
{"ID":3,"code":"AAA","modifieddate":"2019-06-03","user":"Sue"},
{"ID":4,"code":"BBB","modifieddate":"2019-06-10","user":"Rick"},
{"ID":5,"code":"CCC","modifieddate":"2019-06-11","user":"Joe"}
]
let result = array.reduce(function(total, currentValue, currentIndex, arr) {
let index = total.findIndex(function(entry) { return entry.code == currentValue.code; })
if (index >= 0) { // entry already exists
// check modified
if (total[index].modifieddate > currentValue.modifieddate) { // already have most recent of the two
total[index].Count += 1;
} else { // need to replace with more recent
currentValue.Count = total[index].Count + 1;
total[index] = currentValue;
}
} else { // first record for this code
currentValue.Count = 1;
total.push(currentValue);
}
return total;
}, []);
console.log(result);
Here is a working js-fiddle
Note: Comments are made in code block

How to modify a nested json position with a trace string

I am creating a web app in order to do a json builder. The problem is I have the json in javascript and I have a string with the position of the element to change.
For me it's easy to access to it doing for loops, but the goal is update or delete the field or array.
The only success solution I have found, it's an switch with the possibles splited trace array lengths.
Json example:
{
"name" : "Marcelino"
"id" : "${id}"
"poderes":
{
"poder1" : "volar"
"poder2" : "echar fuego"
"poder3" : "${poder4}"
"array":
{
"Elemento1" : "adada"
}
}
}
I want to modify the following key:value pair:
"poderes" : "volar"
I have the trace in a variable:
trace = poderes-poder1
The current solution
...
let traceArray = trace.split("-");
...
switch(traceArray.length){
...
case1:
json[traceArray[0]]
...
case2:
json[traceArray[0]][traceArray[1]]
...
case3:
json[traceArray[0]][traceArray[1]][traceArray[2]]
...
Looking for better solution.
Thanks so much for the help.

You could reduce the path by saving the last key and change either the value or delete this property.
function change(object, path, value) {
var keys = path.split('-'),
last = keys.pop(),
reference = keys.reduce((o, k) => o[k], object);
if (value === DELETE) {
delete reference[last];
} else {
reference[last] = value;
}
}
const DELETE = Symbol('delete this property');
var data = { name: "Marcelino", id: "${id}", poderes: { poder1: "volar", poder2: "echar fuego", poder3: "${poder4}", array: { Elemento1: "adada" } } },
target = 'poderes-poder1';
change(data, target, 'foo')
console.log(data);
change(data, target, DELETE);
console.log(data);
.as-console-wrapper { max-height: 100% !important; top: 0; }

I think the best way you could tackle this is by reading the JSON into a Javascript object, mutate it and then convert it back to JSON:
const hero = JSON.parse(yourJsonString);
hero.poderes.poder1 = "invisibility";
const outputJson = JSON.strigify(hero);

Checking Each Value in For Loop

I've searched for an answer for this but haven't found one that cover this well with a good example.
I have a for loop:
for (var i=0;i<userProfileProperties.length;i++) {
if (userProfileProperties[i].indexOf("ValueImSearchingFor") {
console.log("GOTIT");
}
}
I'm trying to test each value in the loop to see if it contains a certain set of letters. If it doesn't, that value can be dropped. I can't get this to work. I've searched and have found examples but none seem do what I'm trying to do. or at least I've found no "working" example. I'm new to javascript.
So if my values in the loop returned normally would be: Jack User1, Jill User1, and Jerry User2; the values I want returned are all "User1"
I can't get this to work for:
while(userEnumerator.moveNext()){
var oUser = userEnumerator.get_current();
if(oUser.val.indexOf('ValueImsearchingFor') > -1)
{ ... do this} }

Use Array.prototype.filter() method available for arrays as below:
ES5
var res = userProfileProperties.filter(function (val) {
return val.indexOf("ValueImSearchingFor") > -1
});
ES6
let res = userProfileProperties.filter((val) => {
return val.indexOf("ValueImSearchingFor") > -1
});
let userProfileProperties = [
'ValueImSearchingFor 1',
'ValueImSearchingFor 2',
'test',
'ValueImSearchingFor 3',
'test 1'
];
let res = userProfileProperties.filter((val) => {
return val.indexOf("ValueImSearchingFor") > -1
});
console.log(res);

Reconstruct JSON after duplicates have been removed

I have the following JSON -
{
"node1":[
{
"one":"foo",
"two":"foo",
"three":"foo",
"four":"foo"
},
{
"one":"bar",
"two":"bar",
"three":"bar",
"four":"bar"
},
{
"one":"foo",
"two":"foo",
"three":"foo",
"four":"foo"
}
],
"node2":[
{
"link":"baz",
"link2":"baz"
},
{
"link":"baz",
"link2":"baz"
},
{
"link":"qux",
"link2":"qux"
},
]
};
I have the following javascript that will remove duplicates from the node1 section -
function groupBy(items, propertyName) {
var result = [];
$.each(items, function (index, item) {
if ($.inArray(item[propertyName], result) == -1) {
result.push(item[propertyName]);
}
});
return result;
}
groupBy(catalog.node1, 'one');
However this does not account for dupicates in node2.
The resulting JSON I require is to look like -
{
"node1":[
{
"one":"foo",
"two":"foo",
"three":"foo",
"four":"foo"
},
{
"one":"bar",
"two":"bar",
"three":"bar",
"four":"bar"
}
],
"node2":[
{
"link":"baz",
"link2":"baz"
},
{
"link":"qux",
"link2":"qux"
},
]
};
However I cannot get this to work and groupBy only returns a string with the duplicates removed not a restructured JSON?

You should probably look for some good implementation of a JavaScript set and use that to represent your node objects. The set data structure would ensure that you only keep unique items.
On the other hand, you may try to write your own dedup algorithm. This is one example
function dedup(data, equals){
if(data.length > 1){
return data.reduce(function(set, item){
var alreadyExist = set.some(function(unique){
return equals(unique, item);
});
if(!alreadyExist){
set.push(item)
}
return set;
},[]);
}
return [].concat(data);
}
Unfortunately, the performance of this algorithm is not too good, I think somewhat like O(n^2/2) since I check the set of unique items every time to verify if a given item exists. This won't be a big deal if your structure is really that small. But at any rate, this is where a hash-based or a tree-based algorithm would probably be better.
You can also see that I have abstracted away the definition of what is "equal". So you can provide that in a secondary function. Most likely the use of JSON.stringify is a bad idea because it takes time to serialize an object. If you can write your own customized algorithm to compare key by key that'd be probably better.
So, a naive (not recommended) implementation of equals could be somewhat like the proposed in the other answer:
var equals = function(left, right){
return JSON.stringify(left) === JSON.stringify(right);
};
And then you could simply do:
var res = Object.keys(source).reduce(function(res, key){
res[key] = dedup(source[key], equals);
return res;
},{});

Here is my version:
var obj = {} // JSON object provided in the post.
var result = Object.keys(obj);
var test = result.map(function(o){
obj[o] = obj[o].reduce(function(a,c){
if (!a.some(function(item){
return JSON.stringify(item) === JSON.stringify(c); })){
a.push(c);
}
return a;
},[]); return obj[o]; });
console.log(obj);//outputs the expected result
Using Array.prototype.reduce along with Array.prototype.some I searched for all the items being added into the new array generated into Array.prototype.reduce in the var named a by doing:
a.some(function(item){ return JSON.stringify(item) === JSON.stringify(c); })
Array.prototype.some will loop trough this new array and compare the existing items against the new item c using JSON.stringify.

Try this:
var duplicatedDataArray = [];
var DuplicatedArray = [];
//Avoiding Duplicate in Array Datas
var givenData = {givenDataForDuplication : givenArray};
$.each(givenData.givenDataForDuplication, function (index, value) {
if ($.inArray(value.ItemName, duplicatedDataArray) == -1) {
duplicatedDataArray.push(value.ItemName);
DuplicatedArray.push(value);
}
});