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check to see if all objects in an array has a common property

I have an array of objects which I am trying to loop over and check for a common key if it exists for all objects. if the specific key does not exist for all objects I return false.
Here is my code
var x = [{
"item": "alpha",
"value": "red"
}, {
"item": "beta",
"value": "blue"
}, {
"item": "beta",
"value": "gama"
}]
function test(obj) {
var count = 0;
var out = false;
for (var i = 0; i < obj.length; i++) {
if (obj[i].hasOwnProperty('value')) {
count = i;
}
}
if (count == obj.length) {
out = true
}
}
console.log(test(x))
I am getting undefined. Cant figure out what am I missing here

A really simple way to do this is to use Array#every like this
var x = [{
"item": "alpha",
"value": "red"
}, {
"item": "beta",
"value": "blue"
}, {
"item": "beta",
"value": "gama"
}]
function test(obj) {
return obj.every(a => a.hasOwnProperty("value"));
}
console.log(test(x))
Update
As rightfully mentioned by this comment first.

Here can be the simple solution for this object:
var x = [{
"item": "alpha",
"value": "red"
}, {
"item": "beta",
"value": "blue"
}, {
"item": "beta",
"value": "gama"
}];
function test(obj) {
var keyCount = 0;
obj.forEach(function (item, index) {
item.hasOwnProperty('value') && ++keyCount;
});
return keyCount == obj.length;
}
console.log(test(x));

Here is my implementation, which finds every matching key, even nested keys, given a set of objects:
function recurse_obj(obj, cb, _stack = []) {
for (var k in obj) {
cb(k, obj[k], _stack);
if (obj.hasOwnProperty(k) && (obj[k] instanceof Object)) {
_stack.push(k);
recurse_obj(obj[k], cb, _stack);
_stack.pop();
}
}
}
function obj_all_keys(obj) {
var tmp = [];
recurse_obj(obj, (k, v, stack) => {
var ext = (stack.length) ? "." : "";
tmp.push(stack.join(".").concat(ext, k));
});
return tmp;
}
function key_intersection(...objs) {
var lookup = {};
objs.forEach(o => {
obj_all_keys(o).forEach(k => {
if (k in lookup === false)
lookup[k] = 0;
lookup[k]++;
});
});
for (var k in lookup)
if (lookup[k] !== objs.length)
delete lookup[k];
return lookup;
}
Here is the calling code:
var me = { name: { first: "rafael", last: "cepeda" }, age: 23, meta: { nested: { foo: { bar: "hi" } } } };
console.log(key_intersection(me, { name: { first: "hi" } }));
Output: { name: 2, 'name.first': 2 }
The object returned includes only the keys that are found in all the objects, the set intersection, the counts are from book-keeping, and not removed in the callee for performance reasons, callers can do that if need be.
Keys that are included in other nested keys could be excluded from the list, because their inclusion is implied, but I left them there for thoroughness.
Passing a collection (array of objects) is trivial:
key_intersection.apply(this, collection);
or the es6 syntax:
key_intersection(...collection);

How to get an JSON Object based in key using jquery

I'm using jsTree and have tree an structured JSON object.
[{
"id": 1,
"text": "TEXT_ONE",
"children": [
{
"id": 2,
"text": "TEXT_TWO",
"children": [
{
"id": 3,
"text": "TEXT_THREE",
"children": [
]
},
{
"id": 4,
"text": "TEXT_FOUR",
"children": [
]
}
]
},
{
"id": 5,
"text": "TEXT_FIVE",
"children": [
]
}
]
},
{
"id": 6,
"text": "TEXT_SIX",
"children": [ ]
}]
I want to get the the object based on the "id" of the object.
For example if i have a function getIdFromTree(3) it will return me the JSON object as following:
{
"id": 3,
"text": "TEXT_THREE",
"children": []
},
How I do that in Javascript/JQuery?

Try this
function getObjById (tree, id) {
if(tree.id === id) {
return tree;
}
if(tree.children) {
for(var i = 0, l = tree.children.length; i < l; i++) {
var returned = getObjById(tree.children[i], id);
if(returned) {
// so that the loop doesn't keep running even after you find the obj
return returned;
}
}
}
}
Call this as follows
getObjById({children: tree}, 3); // tree is the array object above.

function findById (tree, id) {
var result, i;
if (tree.id && tree.id === id) {
result = tree;
// Revalidate array list
} else if (tree.length) {
for (i = 0; i < tree.length; i++) {
result = findById(tree[i], id);
if (result) {
break;
}
}
// Check childrens
} else if (tree.children) {
result = findById(tree.children, id);
}
return result;
}

Use filter Methode off Array
data.filter(function (obj){ obj.id== 3});

try this.... Es6
function *getObjectById(data, id) {
if (!data) return;
for (let i = 0; i< data.length; i++){
let val = data[i];
if (val.id === id) yield val;
if (val.children) yield *getObjectById(val.children , id);
}
}
now
getObjectById(arrayOfObjects, id).next().value;

try this with most effective and efficient way..
function getObjById (tree, id) {
for(var i= 0;i<tree.length;i++)
{
if(tree[i].id===id)
{
return tree[i];
}
if(tree[i].children)
{
var returned = getObjById(tree[i].children,id);
if(returned!= undefined)
return returned;
}
}
};
link:
https://jsfiddle.net/aa7zyyof/14/

Search dynamic JSON by id

I have a JSON with the following structure:
{
"root": {
"containers": [
{
"id": UNIQUE_ID,
...
"child": [
{
"id": UNIQUE_ID,
...
"child": [...]
}
]
},
{
"id": UNIQUE_ID,
...
"child": [...]
}
]
}
}
root.containers and root.containers.child have the same structure. The thing is that I can have infinite nesting and I don't know beforehand what is the total number of child nodes, since they are added to this JSON dynamically.
I need a function that returns me only the specific object with the given ID as parameter. So it has to dive into the JSON until it finds the child with that ID. I've tried something with .filters but I can't figure out how to search deeper. Probably some search algorithm that I've never implemented in javascript before...
Can someone give me an idea how can I accomplish this? Thanks!

The function that you need is:
function findById(data, id){
var found;
data.forEach(function(o){
if(found){
return;
}
found = o.id === id && o || o.child && findById(o.child, id);
});
return found;
}
And it would be used in this way:
findById(data.root.containers, 1)
Check and run the following snippet. it has some tests, including one case to fail.
var data = {
"root": {
"containers": [
{
"id": 1,
"child": [
{
"id": 2,
"child": [{
id: 3
}, {
id: 4
}]
}
]
},
{
"id": 5,
"child": [{
id: 6
}]
},
{
"id": 7,
"child": []
}
]
}
};
function findById(data, id){
var found;
data.forEach(function(o){
if(found){
return;
}
found = o.id === id && o || o.child && findById(o.child, id);
});
return found;
}
[1,2,3,4,5,6,7,8].forEach(function(v){
console.log('==== Searching for:', v);
console.log(findById(data.root.containers, v));
});

You can use a recursive function like this (https://jsfiddle.net/17qLjufc/):
//this is just a function to check for null or undefined
var notEmpty = function(something){
if(typeof(something) !== 'undefined' && something !== null){
return true;
}
return false;
}
//this is a recursive function that does the search in dept indefinetly (supposing that all the nodes from the containers node on just have child properties)
var findNodeById = function (node, id){
if(notEmpty(node) && notEmpty(node.id) && node.id == id)
return node;
else{
if(notEmpty(node) && notEmpty(node.child)){
for (var i = 0 ; i < node.child.length; i++){
var found = findNodeById(node.child[i], id);
if(found != null)
return found;
}
}
}
return null;
}
//this is going through the containers children and call the search for each of them until the first is found.
var searchById = function(root, id){
var found;
if(notEmpty(root) && notEmpty(root.containers)){
for(var i = 0; i < root.containers.length; i++){
found = findNodeById(root.containers[i], id);
if(found !== null){
break;
}
}
}
return found;
}

Loop through all documents in a nested function

I started using Couchbase for a new project of mine and I hope you can help me solve a problem.
I have two types of documents in my bucket. For example:
{
"id": "A1",
"name": "Name of A",
"type": "A"
}
and
{
"id": "B1",
"name": "Name of B",
"type": "B",
"parentIDs": ["A1", "A4", "A5"]
}
I want to create a view with the following result:
{
"id": "A1",
"name": "Name of A",
"type": "A",
"children": [
{JSON document of child 1},
{JSON document of child 2},
{JSON document of child 3}
]
}
I started to write a function and a nested one, which should iterate through all documents but I must surrender... Can you help me?
function (doc, meta)
{
if(doc.type == "A")
{
emit(doc, GetAllSites(doc));
}
function GetAllSites(doc)
{
var sites = [];
for(var i = 0; i < doc.length; i++)
{
sites.push(doc.id);
}
return sites;
}
}
Thanks
-----------------UPDATE-----------------
I solved my problem this way:
// map function
function (doc, meta)
{
emit(meta.id, doc);
}
// reduce function
function (key, values, rereduce)
{
var result = [];
for(var i = 0; i < values.length; i++)
{
var val1 = values[i];
if(val1.type != "A")
continue;
val1.childrenIDs = [];
for(var j = 0; j < values.length; j++)
{
var val2 = values[j];
switch(val2.type)
{
case "B":
if(contains(val2.parentIDs, val1.id))
val1.childrenIDs.push(val2);
break;
default:
break;
}
}
result.push(val1);
}
return result;
function contains(a, obj) {
var i = a.length;
while (i--) {
if (a[i] === obj) {
return true;
}
}
return false;
}
}
May be no "blue-print" solution but it works and I'll optimize it later. :-)

You can't use nested functions, in you case I'll recommend to use reduce function after map function.
So you need paste you GetAllSites function code to reduce
And don't forget to realize rereduse logic

Change key name in nested JSON structure

I have a JSON data structure as shown below:
{
"name": "World",
"children": [
{ "name": "US",
"children": [
{ "name": "CA" },
{ "name": "NJ" }
]
},
{ "name": "INDIA",
"children": [
{ "name": "OR" },
{ "name": "TN" },
{ "name": "AP" }
]
}
]
};
I need to change the key names from "name" & "children" to say "key" & "value". Any suggestion on how to do that for each key name in this nested structure?

I don't know why you have a semicolon at the end of your JSON markup (assuming that's what you've represented in the question), but if that's removed, then you can use a reviver function to make modifications while parsing the data.
var parsed = JSON.parse(myJSONData, function(k, v) {
if (k === "name")
this.key = v;
else if (k === "children")
this.value = v;
else
return v;
});
DEMO: http://jsfiddle.net/BeSad/

Try this:
function convert(data){
return {
key: data.name,
value: data.children.map(convert);
};
}
Or if you need to support older browsers without map:
function convert(data){
var children = [];
for (var i = 0, len = data.children.length; i < len; i++){
children.push(convert(data.children[i]));
}
return {
key: data.name,
value: children
};
}

You could use a function like this :
function clonerename(source) {
if (Object.prototype.toString.call(source) === '[object Array]') {
var clone = [];
for (var i=0; i<source.length; i++) {
clone[i] = goclone(source[i]);
}
return clone;
} else if (typeof(source)=="object") {
var clone = {};
for (var prop in source) {
if (source.hasOwnProperty(prop)) {
var newPropName = prop;
if (prop=='name') newPropName='key';
else if (prop=='children') newPropName='value';
clone[newPropName] = clonerename(source[prop]);
}
}
return clone;
} else {
return source;
}
}
var B = clonerename(A);
Note that what you have isn't a JSON data structure (this doesn't exist as JSON is a data-exchange format) but probably an object you got from a JSON string.