In a project I'm working on I'm calling an rest-api that returns json as follows:
[
{
"id":0,
"username":"someone0",
"areas":[
],
"role":{
"id":2,
"name":"somerole2",
"users":null
}
},
{
"id":1,
"username":"someone1",
"areas":[
],
"role":{
"id":1,
"name":"somerole1",
"users":null
}
},
{
"id":3,
"username":"someone3",
"areas":[
],
"role":1
}
]
As you can see user 'someone1' and 'someone3' both carry the same role object, but the second time it's referenced (at someone3) it is only referenced by it's id.
Because every response from this api is formatted this way, I'm looking for a generic way to fix this (replace the id-reference with the full object) in pure javascript.
Any common solutions to the seemingly common issue?
PS: I'm sorry for the title, I don't know the right term (suggestions are welcome).
You could simply map a function that makes these corrections to the initial value. Something like this should work if I understand what you are going for:
response = response.map( function(x){
if( (typeof x.role) == "number" )
x.role = { id : x.role };
return x;
});
This however will not give you the names and users field. If this is important, I recommend we iterate through the data once and make a list of roles, then go back and fill in the gaps. This would look like:
roles = {};
response.forEach( function(x){
if( (typeof x.role) != "number" )
roles[x.role.id] = x.role;
});
response = response.map( function(x){
if( (typeof x.role) == "number" )
x.role = roles[x.role];
return x;
});
The output of running that on your data is:
[
{ id: 0,
username: 'someone0',
areas: [],
role: { id: 2, name: 'somerole2', users: null }
},
{ id: 1,
username: 'someone1',
areas: [],
role: { id: 1, name: 'somerole1', users: null }
},
{ id: 3,
username: 'someone3',
areas: [],
role: { id: 1, name: 'somerole1', users: null }
}
]
Related
Given the following object:
let data = { id: 1,
pets: [
{
name: "",
myPets: [
{
name: ""
breed: ""
},
{
name: "Jack"
breed: "poodle"
}
]
]
}
Looking for a cleaner way of writing the following to check for at least one record that has a pet name assigned within the myPets array.
I've used two nested .maps but not sure if I can accomplish the below with a .filter as unsure how to approach this, using .filter?
data.pets.map((pet) => {
if (pet.myPets.length > 0) {
pet.myPets.map((myPet) => {
if (myPet.name) {
console.log("Pet name found");
} else {
console.log("Pet name not found");
});
}
});
I'm writing a back code using NodeJs to fetch some data from backend, I want dataBase data to be like this
like this:
data = [{
name: "Admin",
id: '1',
children: [
{ name: "Admin", id: "1" },
{ name: "groupe1", id: "2" },
{
name: "groupe2", id: "1455", children: [
{ name: "groupe2", id: "1455" },
{ name: "gro", id: "5444" },
{ name: "hhrr", id: "45" }
]
}
]
}]
the idea is simple we have a list of group each group has a parent I want to display all the groups list in an hierarchical way the top one of the tree is done
Some groups are parents and groups in the same time and some others are only groups if the group is not parent we add an object with its name and ID in the array of children of his parent
if this groups is a parent that's mean it has children we add an object with its ID and name in the array of children of his parents, and we add property children for the object which is array named children with for the first time an object with the name and the id of the group etc...
i tryed to do this but it did not work
const getParentsByType = async ({ name, _id }) => {
let parentResult = [
{
id: _id,
name: name,
children: [
{
id: _id,
name: name,
},
],
},
];
parentResult= await findParent(_id, parentResult[0].children, 0);
return parentResult;
};
const findParent = async (parentId, parentResult, itemPos) => {
let children = await Models.GroupModel.find({ parent: parentId, status: true }).select('name _id');
for (let i = 0; i < children.length; i++) {
let childrenList = await Models.GroupModel.find({ parent: children[i]._id, status: true }).select('name _id');
if (childrenList.length != 0) {
parentResult.push(buildParentWithChild(children[i]._id, children[i].name));
findParent(children[i]._id,parentResult.children[i],itemPos++)
} else {
parentResult.push(buildParent(children[i]._id, children[i].name));
}
}
return parentResult
};
and this the model of the data base
const Group = mongoose.Schema({
name: {
type: String,
required: true,
},
status: {
type: Boolean,
required: true,
},
parent: {
type: mongoose.Schema.Types.ObjectId,
ref: 'Group',
},
});
i had two days trying to resolve tis but with no result
i need some helps and Thank you
Try parsing your returned data. It validates your data as objects i dont see any problem with your function regardless i still have no idea what format your a trying to build.
let children = JSON.parse(JSON.stringify(await Models.GroupModel.find({ parent: parentId, status: true }).select('name _id')));
let childrenList = JSON.parse(JSON.stringify(await Models.GroupModel.find({ parent: children[i]._id, status: true }).select('name _id')));
If I understand you right, you want to convert the array returned by Models.GroupModel.find, and which looks like
var dbresult = [
{_id: "1", parent: null, name: "one"},
{_id: "2", parent: "1", name: "two"}
];
into a hierarchical structure. This can be done with a function that adds all children of a given parent p, including, recursively, their children. Like the following:
function children(p) {
var result = [];
for (r of dbresult) if (r.parent === p) {
var row = {_id: r._id, name: r.name};
var chld = children(r._id);
if (chld.length > 0) row.children = chld;
result.push(row);
}
return result;
}
console.log(JSON.stringify(children(null)));
Note that this approach requires only one database access (to fill the dbresult) and is therefore probably faster than your findParent function.
Given an object searchable, is there a simple way of returning all the id values using lodash or underscore.js (or equivalent) where I can define the path to id?
const searchable = {
things: [
{
id: 'thing-id-one',
properties: [
{ id: 'd1-i1' },
{ id: 'd1-i2' },
]
},
{
id: 'thing-id-two',
properties: [
{ id: 'd2-i1' },
{ id: 'd2-i2' },
]
}
]
}
I am looking to see if this is possible in a manner similar to how we can use lodash.get e.g. if we wanted to return the things array from searchable we could do
const things = _.get(searchable, 'things');
I can't seem to find anything similar in the documentation. I am looking for something
that could contain an implementation similar to:
_.<some_function>(searchable, 'things[].properties[].id')
Note: I am well aware of functions like Array.map etc and there are numerous ways of extracting the id property - it is this specific use case that I am trying to figure out, what library could support passing a path as a string like above or does lodash/underscore support such a method.
Found a solution using the package jsonpath
const jp = require('jsonpath');
const result = jp.query(searchable, '$.things[*].properties[*].id')
console.log(result);
// outputs: [ 'd1-i1', 'd1-i2', 'd2-i1', 'd2-i2' ]
you can do it easily in plain js
like this
const searchable = {
things: [
{
id: 'thing-id-one',
properties: [
{ id: 'd1-i1' },
{ id: 'd1-i2' },
]
},
{
id: 'thing-id-two',
properties: [
{ id: 'd2-i1' },
{ id: 'd2-i2' },
]
}
]
}
const search = (data, k) => {
if(typeof data !== 'object'){
return []
}
return Object.entries(data).flatMap(([key, value]) => key === k ? [value]: search(value, k))
}
console.log(search(searchable, 'id'))
_.map and _.flatten together with iteratee shorthands let you expand nested properties. Every time you need to expand into an array, just chain another map and flatten:
const searchable = {
things: [
{
id: 'thing-id-one',
properties: [
{ id: 'd1-i1' },
{ id: 'd1-i2' },
]
},
{
id: 'thing-id-two',
properties: [
{ id: 'd2-i1' },
{ id: 'd2-i2' },
]
}
]
}
// Let's say the path is "things[].properties[].id"
const result = _.chain(searchable)
.get('things').map('properties').flatten()
.map('id').value();
console.log(result);
<script src="https://cdn.jsdelivr.net/npm/underscore#1.13.4/underscore-umd-min.js"></script>
I want to do a database operation only if my barcode is new to the structure.
My plan was either to use the function includes() or simply count the existence in the array.
I have found quite helpful code snippets like countDuplicate and the function include() to do the job but I guess my case is a little bit more specific.
But I not only have an object/array which consists of strings. (1st example)
I have an object which includes different objects and their properties.
//1st example (this works pretty well)
function countDuplicate(array, elem) { //just the special type of syntax for Vue/Node.js
return array.filter(item => item == elem).length;
}
var cars = ["Saab", "Volvo", "BMW", "BMW", "BMW"];
console.log(countDuplicate(cars, "BMW"); //will return 3
console.log(cars.includes("BMW")); //will return true
But as I said I have more a structure like that:
var object = {
sub_object1: { title: "test1", barcode: "0928546725" },
sub_object2: { title: "test2", barcode: "7340845435" },
};
How can I get the same results there?
My plan was to do it like that:
if(countDuplicate(object, "0928546725") == 0)
//... do my operations
But this not work because I don't really understand how I get into the structure of my objects. I experimented with different loops but nothing actually worked.
This is my array:
export default {
data() {
return {
form: {
items: [ //Barcodes
],
status: 1,
rent_time: Date.now()
},
submit: false,
empty: false,
}
},
____________________________________________________________________
Solutions:
I tried the following from #adiga and it works for the example but not for my real case.
This is a screen of my console:
So
A simple object.filter(a => a.barcode == elem) should work - #adiga
Like that?
countDuplicateBarcodes: function(obj, elem) {
//return Object.values(obj).filter(a => a.barcode == elem).length;
return obj.filter(a => a.barcode == elem).length;
}
Doesn't work anymore...
Get all the values of object in an array usingObject.values and then use filter
function countDuplicateBarcodes(obj, elem) {
return Object.values(obj).filter(a => a.barcode == elem).length;
}
const object = {
sub_object1: { title: "test1", barcode: "0928546725" },
sub_object2: { title: "test2", barcode: "7340845435" },
sub_object3: { title: "test3", barcode: "0928546725" }
};
console.log(countDuplicateBarcodes(object, "0928546725"))
If you just want to find a barcode in your object, then your question is a duplicate of for example
https://stackoverflow.com/a/46330189/295783
Changed to match you requirement:
const barcodes = {
sub_object1: { title: "test1", barcode: "0928546725" },
sub_object2: { title: "test2", barcode: "7340845435" },
};
const findMatch = (barcode, barcodes) => JSON.stringify(barcodes).includes(`"barcode":"${barcode}"`);
console.log(
findMatch("0928546725",barcodes)
)
Looking at your code, it appears like you actually use an array of objects and not a nested object. If that's the case, something like this should work:
let scannedTools = [
{barcode: "ABC", createdAt: "today"},
{barcode: "XYZ", createdAt: "123"}
];
function isAlreadyScanned(tool) {
return scannedTools.filter(t => t.barcode == tool.barcode ).length > 0
}
console.log(isAlreadyScanned({barcode: "ABC"}));
console.log(isAlreadyScanned({barcode: "ETRASDASD"}));
console.log(isAlreadyScanned({barcode: "XYZ"}));
I have a json object something like this:
var temp1 = {
name: "AMC",
children: [
{
name: "cde",
children: [
{
name: "AMC",
children: [
{
name: "cde",
children: [
{
name: "AMC",
children: [
//.............. continues as curcular depndency
]
}
]
}
]
}
]
},
{
name: "mnp",
children: [
{
name: "xyz",
children: []
}
]
}
]
}
Due to this cicular dependency, JSON.stringify is failing.
I have done enough google and searching to get the solution for this but could not find much help.
So here basically I want to detect a circular dependency in the json object and add a new key to the object, saying cricular: true and remove all the subsequent node.
So here is the result output what I am looking :
var temp1 = {
name: "AMC",
children: [
{
name: "cde",
circular: true,
children: [ // No children here as it is curcular dependency
]
},
{
name: "mnp",
children: [
{
name: "xyz",
children: []
}
]
}
]
}
There is a way, which I think can solve it, where I can loop through all the children unless there is no children upto maximum 2 levels, but that way I will miss valid children which are having depth more than 3.
I hope my question is clear. If not please let me know I will try to expand this further.
A recursive function solves this:
function check(stack,parent, obj){
stack = stack || []; //stack contains a list of all previously occurred names
var found = stack.find(function(parent){
return (parent==obj.name && obj.children.length>0); //checks to see if the current object name matches any in the stack.
});
if(!found && obj.children.length>0){
stack.push(obj.name); //adds the current object name to the list.
obj.children.forEach(function(child){
check(stack,obj, child);//recursively checks for all children.
})
}
else if(found){
parent.children=[];
parent.circular=true;
stack.pop(obj.name);
return;
}
else{
return;
}
}
check([],temp1, temp1)
This leads to alteration of the original object passed.
Hope this helps!
use console.table(circularObj) to help you in debugging