ReactJS - Convert JSON Array - javascript

I need help for simple question, to convert this:
{
"data": [{
"data_1": {
"name": "name1",
"value": "value1"
},
"data_2": {
"name": "name2",
"value": "value2"
}
}]
}
To this:
I need help for simple question, to convert this:
{
"data": {
"data_1": {
"name": "name1",
"value": "value1"
},
"data_2": {
"name": "name2",
"value": "value2"
}
}
}
Need to remove '[]'.
Thanks a lot!

If I understand you correctly, it's easy enough. You just need to return 0 element from data array.
Here is an example in JavaScript:
const original = {
data: [{
data_1: {
name: "name1",
value: "value1"
},
data_2: {
name: "name2",
value: "value2"
}
}]
};
const converted = {
data: original.data[0]
};

Ideally you want to make a deep copy of those inner objects, and create a new object with them. There are many ways to do this but one of the easiest methods is to stringify them (ie the first element of the array), and then parse that string. That way new references are built, and changes to the original data won't have an effect on the new data.
const data={data:[{data_1:{name:"name1",value:"value1"},data_2:{name:"name2",value:"value2"}}]};
// Stringify, and then parse the string
const copy = (o) => JSON.parse(JSON.stringify(o));
// Assemble the new object by copying the part
// for reuse
const out = { data: copy(data.data[0]) };
// Check that changes made to the original object
// are not reflected in the new object
data.data[0].data_1.name = 'bob';
console.log(out);

Related

Destructuring object with inner array without all keys

I have an object like this:
const objBefore:
{
"id": "3pa99f64-5717-4562-b3fc-2c963f66afa1",
"number": "5000",
"enabled": true,
"classes": [
{
"id": "2fc87f64-5417-4562-b3fc-2c963f66afa4",
"name": "General"
},
{
"id": "7ffcada8-0215-4fb0-bea9-2266836d3b18",
"name": "Special"
},
{
"id": "6ee973f7-c77b-4738-b275-9a7299b9b82b",
"name": "Limited"
}
]
}
Using es6, I want to grab everything in the object except the name key of the inner classes array to pass it to an api.
So:
{
"id": "3pa99f64-5717-4562-b3fc-2c963f66afa1",
"number": "5000",
"enabled": true,
"classes": [
{"id": "2fc87f64-5417-4562-b3fc-2c963f66afa4"},
{"id": "7ffcada8-0215-4fb0-bea9-2266836d3b18"},
{"id": "6ee973f7-c77b-4738-b275-9a7299b9b82b"}
]
}
The closest I got was: let {id, number, enabled, classes: [{id}]} = objBefore;
But it only gets me one id in classes. I've tried spreading above using [...{id}] or [{...id}]. Same thing.
I find it challenging to get the right mental model for how to think about this when it's on multiple levels. In my mind, when I say [...{id}] I'm thinking, "I want the id property as an object in the outer classes array, but give me every id in the array!"
Clearly I'm not thinking about this correctly.
I've tried it using map to get that part but I'm still having trouble combining it back to the original to produce the desired result. for example:
let classIds = objBefore.classes.map(({id}) => {
return {
id
}
})
(Using the map syntax, how can I destructure in the function the other keys that are one level higher?)
To combine them I started trying anything and everything, :
let {id, number, enabled, classIds} = {objBefore, [...classIds]} // returns undefined for all
I'd prefer to do it in one statement. But if that's not possible, then what's a clean way to do it using map?.
You can't destructure and map at the same time in the way you're looking to do it. The main purpose of destructuring assignment is to extract data from an array/object and not for manipulating data. In your case, as you're after an object with the same keys/value as your original object, just with a different classes array, I would instead suggest creating a new object and spreading ... the original object into that. Then you can overwrite the classes array with a mapped version of that array:
const objBefore = { "id": "3pa99f64-5717-4562-b3fc-2c963f66afa1", "number": "5000", "enabled": true, "classes": [ { "id": "2fc87f64-5417-4562-b3fc-2c963f66afa4", "name": "General" }, { "id": "7ffcada8-0215-4fb0-bea9-2266836d3b18", "name": "Special" }, { "id": "6ee973f7-c77b-4738-b275-9a7299b9b82b", "name": "Limited" } ] };
const newObj = {
...objBefore,
classes: objBefore.classes.map(({id}) => ({id}))
};
console.log(newObj);
How about using simple util method with object destructuring, spread operator and map
const objBefore = {
id: "3pa99f64-5717-4562-b3fc-2c963f66afa1",
number: "5000",
enabled: true,
classes: [
{
id: "2fc87f64-5417-4562-b3fc-2c963f66afa4",
name: "General",
},
{
id: "7ffcada8-0215-4fb0-bea9-2266836d3b18",
name: "Special",
},
{
id: "6ee973f7-c77b-4738-b275-9a7299b9b82b",
name: "Limited",
},
],
};
const process = ({ classes, ...rest }) => ({
...rest,
classes: classes.map(({ id }) => ({ id })),
});
console.log(process(objBefore))
In one line, you could do this:
const objAfter = { ...objBefore, classes: objBefore.classes.map(item => ({ id: item.id })) };
Or, if you prefer:
const objAfter = {...objBefore, classes: objBefore.classes.map(({id}) => ({id}))};
There isn't any way in object destructing to copy an entire array of objects into a different array of objects by removing properties so you use .map() for that.

Construct a JSON Payload in javascript

I have to construct a JSON payload that looks like this, can someone help me? I am able to get the straight forward one but unable to build a nested payload. How do I go about adding more nested keys, one inside the other. Also some of the keys and values are dynamic and have to replaced with variables.
{
"format_version": "0.2.19",
"alliances": {
"xyz": {
"environments": {
"prd": {
"teams": {
"abc": {
"action": "edit",
"team": "abc",
"projects": {
"prjabc": {
"project": "prjabc",
"cost_center": "0",
"custom_iam_policies": [],
"iam": {
"view_group_email_name": "abc#email.com",
"sre_admin_group_email_name": "xyz#email.com"
},
"allowed_apis": [
"api1",
"api2"
],
"networks": {
"network1": {
"flags": [
"VM"
],
"region": "sample-region",
"preferred-suffix": "routable"
}
}
}
}
}
}
}
}
}
}
}
Let say you have an object as such
items = {
foo: "bar",
something: "useful"
}
and if you wanted to add other properties or add nested object you can do so like this
subitems = { name: "Johnson" };
items['subitem'] = subitems;
After you've added and finalized the object, you can just use JSON.stringify(items) to convert your object into "payload"

How to get all values of given specific keys (for e.g: name) without loop from json?

I want to fetch all the names and label from JSON without loop. Is there a way to fetch with any filter method?
"sections": [
{
"id": "62ee1779",
"name": "Drinks",
"items": [
{
"id": "1902b625",
"name": "Cold Brew",
"optionSets": [
{
"id": "45f2a845-c83b-49c2-90ae-a227dfb7c513",
"label": "Choose a size",
},
{
"id": "af171c34-4ca8-4374-82bf-a418396e375c",
"label": "Additional Toppings",
},
],
},
]
}
When you say "without loops" I take it as without For Loops. because any kind of traversal of arrays, let alone nested traversal, involve iterating.
You can use the reduce method to have it done for you internally and give you the format you need.
Try this :
const data = {
sections: [
{
id: "62ee1779",
name: "Drinks",
items: [
{
id: "1902b625",
name: "Cold Brew",
optionSets: [
{
id: "45f2a845-c83b-49c2-90ae-a227dfb7c513",
label: "Choose a size"
},
{
id: "af171c34-4ca8-4374-82bf-a418396e375c",
label: "Additional Toppings"
}
]
}
]
}
]
};
x = data.sections.reduce((acc, ele) => {
acc.push(ele.name);
otherName = ele.items.reduce((acc2, elem2) => {
acc2.push(elem2.name);
label = elem2.optionSets.reduce((acc3, elem3) => {
acc3.push(elem3.label);
return acc3;
}, []);
return acc2.concat(label);
}, []);
return acc.concat(otherName);
}, []);
console.log(x);
Go ahead and press run snippet to see if this matches your desired output.
For More on info reduce method
In the context of cJSON
yes, we can fetch the key value for any of the object.
1 - each key value is pointed by one of the objects. will simply fetch that object and from there will get the key value.
In the above case for
pre-requisition: root must contain the json format and root must be the cJSON pointer. if not we can define it and use cJSON_Parse() to parse the json.
1st name object is "sections" will use
cJSON *test = cJSON_GetObjectItem(root, "sections");
char *name1 = cJSON_GetObjectItem(test, "name" )->valuestring;
2nd name key value
cJSON *test2 = cJSON_GetObjectItem(test, "items");
char *name2 = cJSON_GetObjectItem(tes2, "name")->valuestring;
likewise, we can do for others as well to fetch the key value.

Is it possible to access a json array element without using index number?

I have the following JSON:
{
"responseObject": {
"name": "ObjectName",
"fields": [
{
"fieldName": "refId",
"value": "2170gga35511"
},
{
"fieldName": "telNum",
"value": "4541885881"
}]}
}
I want to access "value" of the the array element with "fieldName": "telNum" without using index numbers, because I don't know everytime exactly at which place this telNum element will appear.
What I dream of is something like this:
jsonVarName.responseObject.fields['fieldname'='telNum'].value
Is this even possible in JavaScript?
You can do it like this
var k={
"responseObject": {
"name": "ObjectName",
"fields": [
{
"fieldName": "refId",
"value": "2170gga35511"
},
{
"fieldName": "telNum",
"value": "4541885881"
}]
}};
value1=k.responseObject.fields.find(
function(i)
{return (i.fieldName=="telNum")}).value;
console.log(value1);
There is JSONPath that lets you write queries just like XPATH does for XML.
$.store.book[*].author the authors of all books in the store
$..author all authors
$.store.* all things in store, which are some books and a red bicycle.
$.store..price the price of everything in the store.
$..book[2] the third book
$..book[(#.length-1)]
$..book[-1:] the last book in order.
$..book[0,1]
$..book[:2] the first two books
$..book[?(#.isbn)] filter all books with isbn number
$..book[?(#.price<10)] filter all books cheapier than 10
$..* All members of JSON structure.
You will have to loop through and find it.
var json = {
"responseObject": {
"name": "ObjectName",
"fields": [
{
"fieldName": "refId",
"value": "2170gga35511"
},
{
"fieldName": "telNum",
"value": "4541885881"
}]
};
function getValueForFieldName(fieldName){
for(var i=0;i<json.fields.length;i++){
if(json.fields[i].fieldName == fieldName){
return json.fields[i].value;
}
}
return false;
}
console.log(getValueForFieldName("telNum"));
It might be a better option to modify the array into object with fieldName as keys once to avoid using .find over and over again.
fields = Object.assign({}, ...fields.map(field => {
const newField = {};
newField[field.fieldName] = field.value;
return newField;
}
It's not possible.. Native JavaScript has nothing similar to XPATH like in xml to iterate through JSON. You have to loop or use Array.prototype.find() as stated in comments.
It's experimental and supported only Chrome 45+, Safari 7.1+, FF 25+. No IE.
Example can be found here
Clean and easy way to just loop through array.
var json = {
"responseObject": {
"name": "ObjectName",
"fields": [
{
"fieldName": "refId",
"value": "2170gga35511"
},
{
"fieldName": "telNum",
"value": "4541885881"
}]
}
$(json.responseObject.fields).each(function (i, field) {
if (field.fieldName === "telNum") {
return field.value // break each
}
})

Accessing JavaScript Sub-properties by Name

I wrote the following JavaScript function (part of a larger "class") to help ensure anybody using the object stores attribute values in the "values" property.
function _updateAttributes(attribute, value) {
_attributes[attribute] = { values: { value: value }};
}
It works fine for a flat structure, but falls apart when I start trying to use it for sub-properties.
After running the following code:
myEntity.updateAttribute('name', 'Frankenstein');
myEntity.updateAttribute('name.source', 'John Doe');
I'd like the following structure:
{
"attributes": {
"name": {
"values": {
"value": "Frankenstein"
},
"source": {
"values": {
"value": "JohnDoe"
}
}
}
}
}
Instead, it's coming out like this:
{
"attributes": {
"name": {
"values": {
"value": "Frankenstein"
}
},
"name.source": {
"values": {
"value": "JohnDoe"
}
}
}
}
Is there any clean way to write this JavaScript or will I be faced with splitting out the strings and manually building the structure?
NOTE: I realize even the preferred structure is a little odd, but there's a Java object I'm mapping to that expects this format, so I don't have any options here.
You'll have to parse the string (parse is a bit strong, just a single split('.') with a loop).
But frankly, the cleaner way would simply be:
myEntity.name = {values: 'Frankenstein'};
myEntity.name.source = {values: 'John Doe'};

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