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How can I pull a value from a JSON object from within another array?

My question title may not be the accurate way to describe this issue but it is the best I could come up with. I will make this very easy -- I am trying to get the value of VALUEIWANT from the below JSON object.
Any help would be greatly appreciated as I have been trying various methods on w3 schools for 2 hours now.
The closest I have gotten by hard coding was below:
const x =
{ "UserAttributes":
[ { "Name" : "sub"
, "Value": "54f5cdfb-6ec7-4683-fdasfasdf-2324234234"
}
, { "Name" : "custom:var"
, "Value": "VALUEIWANT"
}
, { "Name" : "email"
, "Value": "test.user#email.com"
}
]
, "Username": "testuser"
}
const y = x.UserAttributes[1].Value
// y here would result in VALUEIWANT
The problem with this is I am not sure that the variable will always be at index 1.
EDIT For Clarity My goal is to be able to retrieve this value of "VALUEIWANT" in my console. I need to be able to access the value by using the paired Name of "custom:var". I am unsure if this is possible.

The problem with this is I am not sure that the variable will always
be at index 1.
You need to find the index using findIndex (MDN)
const x = {
"UserAttributes": [{
"Name": "sub",
"Value": "54f5cdfb-6ec7-4683-fdasfasdf-2324234234"
}, {
"Name": "email",
"Value": "test.user#email.com"
}, {
"Name": "custom:var",
"Value": "VALUEIWANT"
}],
"Username": "testuser"
}
const index = x.UserAttributes.findIndex(item => item.Name === "custom:var");
const y = x.UserAttributes[index].Value;
console.log(y);
An helper function for this would be like below
const x = {
"UserAttributes": [{
"Name": "sub",
"Value": "54f5cdfb-6ec7-4683-fdasfasdf-2324234234"
}, {
"Name": "custom:var",
"Value": "VALUEIWANT"
}, {
"Name": "email",
"Value": "test.user#email.com"
}],
"Username": "testuser"
}
function getValue(x, name) {
const index = x.UserAttributes.findIndex(item => item.Name === name);
return index === -1 ? null : x.UserAttributes[index].Value;
}
// get email
console.log(getValue(x, 'email'));
// get custom:var
console.log(getValue(x, 'custom:var'))

Use Array.find on the x.UserAttributes array to search for the item with name of "custom:var", and take the value:
const valueYouWant = x.UserAttributes.find(ua => ua.Name === "custom:var").Value;

Filter out objects in array if one value is the same

I am fetching data from an api that, sometimes, gives me multiple objects with the same values, or very similar values, which I want to remove.
For example, I might get back:
[
{
"Name": "blah",
"Date": "1992-02-18T00:00:00.000Z",
"Language": "English",
},
{
"Name": "blahzay",
"Date": "1998-02-18T00:00:00.000Z",
"Language": "French",
}, {
"Name": "blah", // same name, no problem
"Date": "1999-02-18T00:00:00.000Z", // different date
"Language": "English", // but same language
},
]
So I want to check that no two objects have a key with the same "Language" value (in this case, "English").
I would like to get the general process of filtering out the entire object if it's "Language" value is duplicated, with the extra issue of not having the same number of objects returned each time. So, allowing for dynamic number of objects in the array.
There is an example here:
Unexpeected result when filtering one object array against two other object arrays
but it's assuming that you have a set number of objects in the array and you are only comparing the contents of those same objects each time.
I would be looking for a way to compare
arrayName[eachObject].Language === "English"
and keep one of the objects but any others (an unknown number of objects) should be filtered out, most probably using .filter() method along with .map().

The below snippets stores the languages that have been encountered in an array. If the current objects language is in the array then it is filtered out. It makes the assumption that the first object encountered with the language is stored.
const objs = [
{
"Name": "blah",
"Date": "1992-02-18T00:00:00.000Z",
"Language": "English",
},
{
"Name": "blahzay",
"Date": "1998-02-18T00:00:00.000Z",
"Language": "French",
}, {
"Name": "blah", // same name, no problem
"Date": "1999-02-18T00:00:00.000Z", // different date
"Language": "English", // but same language
},
],
presentLanguages = [];
let languageIsNotPresent;
const objsFilteredByLanguage = objs.filter(function (o) {
languageIsNotPresent = presentLanguages.indexOf(o.Language) == -1;
presentLanguages.push(o.Language);
return languageIsNotPresent;
});
console.log(objsFilteredByLanguage);

You could take a hash table and filter the array by checking Name and Language.
var array = [{ Name: "blah", Date: "1992-02-18T00:00:00.000Z", Language: "English" }, { Name: "blahzay", Date: "1998-02-18T00:00:00.000Z", Language: "French" }, { Name: "blah", Date: "1999-02-18T00:00:00.000Z", Language: "English" }],
hash = {},
result = array.filter(({ Name, Language }) => {
var key = `${Name}|${Language}`;
if (!hash[key]) return hash[key] = true;
});
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }

Using Set makes it easy to remove duplicates for as many keys as you like. I tried to be as verbose as possible so that each step was clear.
var objects = [{ "Name": "blah", "Date": "1992-02-18T00:00:00.000Z", "Language": "English", }, { "Name": "blah", "Date": "1998-02-18T00:00:00.000Z", "Language": "French", }, { "Name": "blah", "Date": "1999-02-18T00:00:00.000Z", "Language": "English" }];
function uniqueKeyVals(objects, key) {
const objVals = objects.map(object => object[key]); // ex. ["English", "French", "English"]
return objects.slice(0, new Set(objVals).size); // ex. { "English", "French" }.size = 2
}
function removeKeyDuplicates(objects, keys) {
keys.forEach(key => objects = uniqueKeyVals(objects, key));
return objects;
}
// can also use uniqueKeyVals(key) directly for just one key
console.log("Unique 'Language': \n", removeKeyDuplicates(objects, ["Language"]));
console.log("Unique ['Language', 'Name']: \n", removeKeyDuplicates(objects, ["Language", "Name"]));

I would use the underscore module for JavaScript and the unique function in this scenario. Here is a sample array of data objects:
let data = [{
name: 'blah',
date: Date.now(),
language: "en"
},
{
name: 'noblah',
date: Date.now(),
language: 'es'
},
{
name: 'blah',
date: Date.now(),
language: 'en'
}];
Then we can use the unique function in the underscore library to only return a copy of the data that has unique values associated with the language key:
const result = _.unique(data, 'language');

How can I combine this data into one Object?

This one is a tricky one.
So, lets say I have two JS objects that are fetched via REST call, via two callbacks.
So, we have:
call1() - POST method - parsed JSON to JS object, route: {{url}}/data
call1.json:
"data": [
{
"id": "1",
"volume:" "2000"
},
{
"id": "2",
"volume:" "3000"
},
{
"id": "3",
"volume:" "4000"
},
{
"id": "4",
"volume:" "5000"
}
];
call2(req.body.id) - GET method - parsed JSON to JS object, route: {{url}}/data/:id
For example, if I pass req.body.id as = 1 got from the first response, it will open data for that id. So:
return call2(2) will return the data from this JSON: call2.json:
"data": [
{
"id": "1",
"add_data": "important string",
"add_data_2": "important string two"
},
];
The bottom line is, when doing the {{url}}/data route call - call() I need to serve all the data from {{url}}/data/:id routes, and bind them to the correct id. So, for example, the scenario I am trying to achieve is this:
Inside call(): get call1.json: data, do as many call2(req.body.id) calls as there are ids in the first object and then combine add_data and add_data_two values in the first object. So for example the final object would look like this.
console.log(response)
"data": [
{
"id": "1",
"volume:" "2000",
"add_data": "important string",
"add_data_2": "important string two"
},
{
"id": "2",
"volume:" "3000",
"add_data": "important string",
"add_data_2": "important string two"
},
{
"id": "3",
"volume:" "4000",
"add_data": "important string",
"add_data_2": "important string two"
},
{
"id": "4",
"volume:" "5000",
"add_data": "important string",
"add_data_2": "important string two"
}
];
This is what I have tried so far:
async get_data(req) {
try {
const objFirst = await call1(); //gets data
let objTwo = '';
for (let i = 0; i < objFirst.data.length; i++) {
objTwo = await call2({id: objFirst.data[i].id}) //gets data
}
return objFirst;
} catch(err) {
console.log("Error: ", err)
}
}
But it does not work. How can I get all data, and make as many as call2(id) as there are ids and combine that all in one object? Basically, I need to repeat this callback -> call2(id) as many ids we receive in call1().
Thanks, sorry if it looks like a mess.

You can use the map function and spread operator for this. Something like below.
Call2 function just simulates what an endpoint would return, but you get the idea.
var data = [
{
id: 1,
add_data: "1111"
},
{
id: 2,
add_data: "2222"
}
];
var data2 = [
{
id: 1,
volume: "bla"
},
{
id: 2,
volume: "bla"
}
];
function call2(id) {
return data2.filter(x => x.id == id)[0];
}
var result = data.map(x => {
var response = call2(x.id);
return {
...x,
...response
}
})
console.dir(result[0]);
The speed of your solution (loop through an array and doing http calls to get more data is really slow). If you have a lot of these functions that needs to combine data from different datasources, and depending on your project size, i would look into either RXJS or GraphQL (If you really need performance). RXJS have great functions to merge, combine, map etc data.
RXJS
GraphQL

How to delete nested json key dynamically?

This is the sample json:
{
"search": {
"facets": {
"author": [
],
"language": [
{
"value": "nep",
"count": 3
},
{
"value": "urd",
"count": 1
}
],
"source": [
{
"value": "West Bengal State Council of Vocational Education & Training",
"count": 175
}
],
"type": [
{
"value": "text",
"count": 175
}
],
}
}
There are several ways to delete key search.facets.source:
delete search.facets.source
delete jsobObj['search']['facets']['source']
var jsonKey = 'source';
JSON.parse(angular.toJson(jsonObj), function (key, value) {
if (key != jsonKey)
return value;
});
Above 1 & 2 are not dynamic, and 3 is one of the way but not a proper way. Because if source is present in another node then it will not work. Please anybody can tell me how to delete it dynamically in any kind of nested key. Because we can not generate sequence of array dynamically in above 2.

Assuming you're starting from this:
let path = 'search.facets.source';
Then the logic is simple: find the search.facets object, then delete obj['source'] on it.
Step one, divide the path into the initial path and trailing property name:
let keys = path.split('.');
let prop = keys.pop();
Find the facets object in your object:
let parent = keys.reduce((obj, key) => obj[key], jsonObj);
Delete the property:
delete parent[prop];

I have found out another solution, it is very easy.
var jsonKey = 'search.facets.source';
eval('delete jsonObj.' + jsonKey + ';');

How to parse a JSON array string in JavaScript?

I have an JSON array like this
var filter_value_data = [{"Status":[{"name":"Open","id":"1"},{"name":"Pending","id":"2"},{"name":"Resolved","id":"3"},{"name":"Closed","id":"4"},{"name":"Evaluation","id":"5"}]},{"Payment Status":[{"name":"Paid","id":"10"},{"name":"UnPaid","id":"11"},{"name":"Part Paid","id":"12"}]},{"Priority":[{"name":"Low","id":"6"},{"name":"Medium","id":"7"},{"name":"High","id":"8"},{"name":"Urgent","id":"9"}]}]
I have tried filter_value_data["Status"] which is obviously wrong. How do I get the JSON elements for Status using the names like Status,Payment Status?

filter_value_data is an array (having []), so use filter_value_data[0].Status to get the first element-object with property "Status".
It is always good to format your code in order to see the hierarchy of the structures:
var filter_value_data = [
{
"Status": [
{
"name": "Open",
"id": "1"
}, {
"name": "Pending",
"id": "2"
}, ...
]
}, {
"Payment Status": [
{
"name": "Paid",
"id": "10"
}, ...
]
}, {
"Priority": [
{
"name": "Low",
"id": "6"
}, ...
]
}
];

With your current JSON you can't get the elements with the name alone.
You can get Status with filter_value_data[0]['Status'] and Payment status with filter_value_data[1]['Payment Status'].
This is because the keys are in seperate objects in the array.
In order to get them with filter_value_data['Status'] you need to change your JSON to
var filter_value_data = {
"Status":[
{"name":"Open","id":"1"},
{"name":"Pending","id":"2"},
{"name":"Resolved","id":"3"},
{"name":"Closed","id":"4"},
{"name":"Evaluation","id":"5"}
],
"Payment Status":[
{"name":"Paid","id":"10"},
{"name":"UnPaid","id":"11"},
{"name":"Part Paid","id":"12"}
],
"Priority":[
{"name":"Low","id":"6"},
{"name":"Medium","id":"7"},
{"name":"High","id":"8"},
{"name":"Urgent","id":"9"}
]
};
I wrote this on my phone so it's not as well-formatted as usual. I'll change it ASAP.

With your current JSON, created a result which might be helpful for you.
JS:
$.each(filter_value_data,function(ind,val){
var sta = val.Status; // Status Object get displayed
for(var i=0;i<sta.length;i++){
var idVal= sta[i].id;
var nameVal = sta[i].name;
Statusarray.push(idVal,nameVal);
console.log(Statusarray);
}
})
FiddleDemo

You can use below code, it will return status object
filter_value_data[0]['Status']
filter_value_data[0]['Payment Status']
to get Single value you use :
filter_value_data[0]['Status'][0]['name']