We Keep Coding

Iterate through array of objects,not giving required output

given code
[
{
"data": [
{
"text_name": "test",
"text_url": "https://www.news18.com/topics/gold-prices/1",
"is_new": "1"
},
{
"text_name": "test2",
"text_url": "https://www.news18.com/topics/gold-prices/2",
"is_new": "0"
}
],
"slug": "bollywood",
"heading": "testing",
"status": "1",
"is_open_new": "1",
"order_data": "2",
"section_dropdown": "bollywood"
}
]
I want to iterate through this given code snippet and get the data.
const trendingTopicsData = trendingTopics.data
but this is showing null

Since the object in the snippet is an array, first you have to get the index of the item you want to work with (in this case the first item — index 0). Then you can iterate through the data array however you want (loop, forEach, map etc.).
Try:
const trendingTopicsData = trendingTopics[0].data
Here it is as a runnable snippet:
const trendingTopics = [
{
"data": [
{
"text_name": "test",
"text_url": "https://www.news18.com/topics/gold-prices/1",
"is_new": "1"
},
{
"text_name": "test2",
"text_url": "https://www.news18.com/topics/gold-prices/2",
"is_new": "0"
}
],
"slug": "bollywood",
"heading": "testing",
"status": "1",
"is_open_new": "1",
"order_data": "2",
"section_dropdown": "bollywood"
}
]
// Get trending topics data array
const trendingTopicsData = trendingTopics[0].data;
console.log("Data array:", trendingTopicsData)
// Iterate through each of the items in the data array
trendingTopicsData.forEach((dataItem, index) => console.log(`Data item #${index}:`, dataItem));

The object you are trying to access is inside an array. You will have to loop through the array
trendingTopics.forEach(topic => {
// do something with topic.data
})

How to generate dynamically two arrays at same time with Formik

I working in a form who generate fields dynamically using formik with the <FieldArray />that acts as a functional component.
So, I have this object to send on submit to my backend:
{
"tapes": [
{
"name": "",
"elements": [
{
"propsOne": "",
"propsTwo": "",
"view": 0,
}
]
}
],
"typeOptions": []
}
As you can see, I have two arrays to working in this json object, one is Tapes who has Elements to work together and typeOptions who has values to send. My proposal is to send in a form with dynamic fields to my backend when whenever the user add new tapes and add new field props which will be rendered later in a mobile app.
Assuming the user added two new tapes and added two new elements for each one, the result of this json would be this:
{
"tapes": [
{
"name": "TapeOne",
"elements": [
{
"propsOne": one,
"propsTwo": two,
"view": 0,
},
{
"propsOne": 1,
"propsTwo": 2,
"view": 0,
}
]
},
{
"name": "TapeTwo",
"elements": [
{
"propsOne": one,
"propsTwo": two,
"view": 0,
},
{
"propsOne": 1,
"propsTwo": 2,
"view": 0,
}
]
}
],
"typeOptions": []
}
Well, so far so good, I can form a dynamic generation of Tapes and Elements according to the user's request, but there is a moment when the user asks for an option selector and the value I get in Elements is in the View, where number by the value of 1 is required.
{
"tapes": [
{
"name": "",
"elements": [
{
"propsOne": "",
"propsTwo": "",
"view": 1,
}
]
}
],
"typeOptions": [
{
"values": []
}
]
}
It is at this point that I need to retrieve the values that it passes on in these fields that will be dynamically generated and insert them into a new array that is called typeOptions in its values, the flow being like this:
The user will ask for a field who has multiple fields, like a selector.
This field will be generated in Tapes, Elements with the value being assigned to view with 1
The user will pass the values in these fields and they will be placed in typeOptions.values
So, the user add this new field and when this happens, I need pass the values that will be passed on fields will be generated for him.
The result needs be like this:
{
"tapes": [
{
"name": "",
"elements": [
{
"propsOne": "One",
"propsTwo": "Two",
"view": 1,
}
]
}
],
"typeOptions": [
{
"values": ["ValueOne", "ValueTwo", "ValueThree"]
}
]
}
Or when two Elements has the same view like 1:
{
"tapes": [
{
"name": "",
"elements": [
{
"propsOne": "One",
"propsTwo": "Two",
"view": 1,
},
{
"propsOne": "1",
"propsTwo": "2",
"view": 1,
}
]
}
],
"typeOptions": [
{
"values": ["ValueOne", "ValueTwo", "ValueThree"]
},
{
"values": ["Value1", "Value2", "Value3"]
}
]
}
I've already tried to use two <FieldArray /> having one inside the other, as I already do for Tapes and Elements, because with this I could use the map function to get the view value and add a conditional to permeate two new <FieldArray /> to add the values not only for each object selected inside the typeOptions, but also for each value that is inserted together.
What is the best way and best practice to do this?

Nested forEach issue

I have two arrays of object, the first array (printers, around 80 elements) is made of the following type of objects:
[{
printerBrand: 'Mutoh',
printerModel: 'VJ 1204G',
headsBrand: 'Epson',
headType: '',
compatibilty: [
'EDX',
'DT8',
'DT8-Pro',
'ECH',
],
cartridges: [],
},
....
]
The second array (cardridges, around 500 elements) is made of the following type of objects:
[
{
"customData": {
"brand": {
"value": {
"type": "string",
"content": "ECH"
},
"key": "brand"
},
"printer": {
"value": {
"type": "string",
"content": "c4280"
},
"key": "printer"
}
},
"name": "DT8 XLXL",
"image": {
"id": "zLaDHrgbarhFSnXAK",
"url": "https://xxxxxxx.net/images/xxxxxx.jpg"
},
"brandId": "xxxxx",
"companyId": "xxxx",
"createdAt": "2018-03-26T14:39:47.326Z",
"updatedAt": "2018-04-09T14:31:38.169Z",
"points": 60,
"id": "dq2Zezwm4nHr8FhEN"
},
...
]
What I want to do first is to is to iterate through the first array and and then iterate for all the cardridge available: if a the value customData.brand.value of a cardridge is included inside the array 'compatibility' of a printer, then I have to add this cardridge object inside the cardridges array of this printer. I have tried but somehow the iteration doesn't take place correctly. This is what I tried:
printers.forEach((printerItem) => {
const printer = printerItem;
printer.compatibilty.forEach((compatibilityItem) => {
const compatibility = compatibilityItem;
cardridges.forEach((cartridge) => {
if (compatibility === cartridge.customData.brand.value.content) {
printer.cartridges.push(cartridge);
}
});
});
});
What am I doing wrong?

You're accessing the wrong property. It should be cartridge.customData.brandName.value.content, carefully note brandName.value rather than brand.value

Your issue is that you're accessing it by the wrong property - brand and not brandName.
Furthermore, if you're targeting everything but IE, you could simplify your nested for loops to utilize some fancy ES6 array methods.
printers.forEach((p) => {
p.cartridges.push(cartridges.filter((c) => {
const brandName = c.customData.brandName.value.content;
return p.compatibilty.includes(brandName);
}));
});

How to delete a paticular Object in an array inRethinkDB

I am Just trying to learn RethinkDB.I am little Bit Confused That how to delete an single Object in an array,What is the Exact query I have to use if i have to delete this Object
{
"name": "Ram" ,
"username": "B97bf210-c4d2d-11e6-b783-07b5fev048705"
}
from whoLikedIt Array
My data
{
"comments": [ ],
"id": "c242c74d-03d9-4963-9a22-4779facb8192" ,
.....
"views": 0 ,
"whoLikedIt": [
{
"name": "Vignesh Warar" ,
"username": "d97bf210-c42d-11e6-b783-07b5fe048705"
},
{
"name": "Ram" ,
"username": "B97bf210-c4d2d-11e6-b783-07b5fev048705"
},
]
.....
}
My Try
r.db('image').table('posts').get('c242c74d-03d9-4963-9a22-4779facb8192').update(
{whoLikedIt:r.row('whoLikedIt').filter({username:"B97bf210-c4d2d-11e6-b783-07b5fev048705"}).delete()}
)
Throws Me a error
e: Cannot nest writes or meta ops in stream operations. Use FOR_EACH instead in:

You want:
r.db('image').table('posts').get('c242c74d-03d9-4963-9a22-4779facb8192').update(function(row) {
return {whoLikedIt: row('whoLikedIt').filter(function(obj) {
return obj('username').ne("B97bf210-c4d2d-11e6-b783-07b5fev048705");
})};
})

How can I return a document/node from a JavaScript function?

If I do something like select from #12:1, obviously, it will return the full document:
{
"result": [
{
"#type": "d",
"#rid": "#12:1",
"#version": 1,
"#class": "Package",
"name": "MsPortfolioStack4.Repository-1.0.4549.25474-alpha",
"p_name": "MsPortfolioStack4.Repository",
"p_ver": "1.0.4549.25474-alpha",
"tags": [
"#14:1",
"#14:2"
],
"#fieldTypes": "tags=z"
}
],
"notification": "Query executed in 0.022 sec. Returned 1 record(s)"
}
Now, if I have a JS function that does this:
function return_node(query) {
return query;
}
And I execute select return_node((select from #12:1)), I only get the RID:
{
"result": [
{
"#type": "d",
"#rid": "#-2:1",
"#version": 0,
"return_node": [
"#12:1"
],
"#fieldTypes": "return_node=z"
}
],
"notification": "Query executed in 0.058 sec. Returned 1 record(s)"
}
Is it possible to return an actual expanded document rather than just the RID? At the moment, the fastest way seems to be to traverse the results, but that's redundant.

You can change the JS function
var db=orient.getDatabase();
return db.query(query);
and execute
select expand(return_node("select from #12:1")) from (select return_node("select from #12:1"))