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Finding nested object data using basic JavaScript

I want to loop through 600+ array items in an object and find one particular item based on certain criteria. The array in the object is called "operations" and its items are arrays themselves.
My goal is to get the index of operation's array item which has the deeply nested string "Go".
In the sample below this would be the first element. My problem is that I can check if an array element contains "call" and "draw" but I don't know how to test for the nested dictionary "foobar". I only have basic JavaScript available, no special libraries.
let json = {
"head": {},
"operations": [
[
"call",
"w40",
"draw",
{
"parent": "w39",
"style": [
"PUSH"
],
"index": 0,
"text": "Modify"
}
],
[
"call",
"w83.gc",
"draw",
{
"foobar": [
["beginPath"],
[
"rect",
0,
0,
245,
80
],
["fill"],
[
"fillText",
"Go",
123,
24
],
[
"drawImage",
"rwt-resources/c8af.png",
]
]
}
],
[
"create",
"w39",
"rwt.widgets.Menu",
{
"parent": "w35",
"style": [
"POP_UP"
]
}
],
[
"call",
"w39",
"draw",
{
"parent": "w35",
"style": [
"POP_UP"
]
}
]
]
};
let index = "";
let operationList = json.operations;
for (i = 0; i < operationList.length; i++) {
if (operationList[i].includes('call') && operationList[i].includes('draw')) //missing another check if the dictionary "foobar" exists in this element )
{
index = i;
}
}
document.write(index)

I'll preface by saying that this data structure is going to be tough to manage in general. I would suggest a scheme for where an operation is an object with well defined properties, rather than just an "array of stuff".
That said, you can use recursion to search the array.
If any value in the array is another array, continue with the next level of recursion
If any value is an object, search its values
const isPlainObject = require('is-plain-object');
const containsTerm = (value, term) => {
// if value is an object, search its values
if (isPlainObject(value)) {
value = Object.values(value);
}
// if value is an array, search within it
if (Array.isArray(value)) {
return value.find((element) => {
return containsTerm(element, term);
});
}
// otherwise, value is a primitive, so check if it matches
return value === term;
};
const index = object.operations.findIndex((operation) => {
return containsTerm(operation, 'Go');
});

Concatenate arrays from the same array in JavaScript

I have an array like this:
[
{
"id": 10002,
"flag": false,
"list": [
"aaa",
"bbb"
]
},
{
"id": 10001,
"flag": true,
"list": [
"10002",
"10003"
]
},
{
"id": 10003,
"flag": false,
"list": [
"ccc",
"ddd"
]
}
]
i tried this
initially i have "10001" value so iterate this array to take "list" array if flag==true then stored into newarray. but its not working.
I want it to be like this: [ "aaa", "bbb", "ccc", "ddd" ].

If i understand correctly this is what you want:
const someArray = [
{
"id": 10001,
"list": [
"10002",
"10003"
]
},
{
"id": 10002,
"list": [
"aaa",
"bbb"
]
},
{
"id": 10003,
"list": [
"ccc",
"ddd"
]
}
];
const [head,...rest] = someArray;
const result = head.list.reduce((acc,currentId)=>acc.concat(rest.find(({id})=> id === parseInt(currentId)).list),[]);
Here is a jsFiddle https://jsfiddle.net/sudakatux/9hju85mt/22/
Explanation:
take the head and splitted from the rest since the head contains the ids.
using the head as a dictionary find each list for each id in the head and concatenate
note the id must be in the subsequent list else it will fail with undefined. if you want to account for this error you can set a defualt empty object with a list. for example this part:
rest.find(({id})=> id === parseInt(currentId)).list
Will look like
rest.find(({id})=> id === parseInt(currentId)) || {list:[]}).list
Which basically means if its undefined return an object that has an empty list so then it will concatenate an empty list which results in being the same list. (like multiplying by 1 in a multiplication)
Hope it helps.
EDIT after your edit.
If your array is in different order you need to find the dictonary and then the logic is the same
const [newHead] = otherArray.filter(({list}) => list.every(elem=>!isNaN(elem)));
const result2 = newHead.list.reduce(
(acc,currentId) =>acc.concat(otherArray.find(({id})=> id === parseInt(currentId)).list),[]);
if you are testing for the flag then your head filter would look like. the blocks are the same the only thing that changes is the condition.
const [newHead] = otherArray.filter(({flag}) => flag));
(note* that instead of using the rest i used the complete array(otherArray). since im targeting equality.
Im using filter and extracting the first element of the result. because im accounting for the possibility that in the future you may have more than one "dictionary element". if thats the case in the future then you just have to concat the lists from the filter result

const array = [
{
id: 10001,
flag: true,
list: ["10002", "10003"]
},
{
flag: false,
id: 10002,
list: ["aaa", "bbb"]
},
{
flag: false,
id: 10003,
list: ["ccc", "ddd"]
}
];
const isHead = item => item.flag && item.id === 10001;
const head = array.find(isHead);
const rest = array.filter(item => !isHead(item));
const result = rest
.flatMap(item =>
head.list.includes(item.id.toString()) && item.list
);
console.log(result);

You can map over the list of the first item and concat all the lists from those ids.
const mapItems = (input) => {
const source = input[0].list;
source.reduce((results, id) => {
return results.concat(input.find(item => item.id === id).list);
}, []);
};
mapItems([
{
"id": 10001,
"list": [
"10002",
"10003"
]
},
{
"id": 10002,
"list": [
"aaa",
"bbb"
]
},
{
"id": 10003,
"list": [
"ccc",
"ddd"
]
}
]);

You can fetch the values of the list of first object in the array as arr[0]['list']
Once you have these values (10002,10003) then you can fetch the list values of remaining objects in the array whose id key matches one of the above values.
if(arr[i]['id'] == 10002 || arr[i]['id'] == 10003){
//fetch the list values
}

Creating an object from API data and adding it to an array dynamically

I have a data set that I'm pulling in from a database. It's one dimensional and I basically need to make it more structured. I refer to it as "flat".
I need to display a heading, and items under that heading that are related to the heading.
The data comes in as having and section_name (the heading) and item_name (items) and other data unique to each item like download URLs etc.
item_name(item)_______section_name(header)
first_________________Funds
second________________Funds
third_________________Funds
fourth________________Literature
fifth_________________Literature
sixth_________________Literature
seventh_______________Literature
eighth________________DueDilligence
I don't know what any of the names will be for the items or sections, or how many items, sections, or items per section. As I said, it's very flat. This needs to be fully dynamic which is why this is complicating things for me.
Here is what I've done.
API call to retrieve data. Store data in a state as an array (it comes in as an array of objects).
I create an empty array to store my newly structured data.
I loop through the data with a foreach.
I create a new object for my new data to add to the new array so I can loop over it later.
I first check to make sure the data exists.
To create the headers I check to see if my new empty array is actually empty OR my section_name is not the same as the last one.(in the original data array I got from the API call)
I store the section_names as an object in the new array (newArray.push(newObject)
I've gotten this far. Now I need to take the item_names that correlates to the section_names and store them in the object under each header name, or at least in the same index.
_generateInfo() {
let dataArray = this.state.stepTwoData
let newArray =[]
dataArray.forEach(function(item, index) {
let newObject = {}
if (index > 0) {
if (newArray.length === 0 || item.investor_portal_section_name !== dataArray[index -1].investor_portal_section_name) {
newObject["name"] = item.investor_portal_section_name
newObject["items"] = []
newArray.push(newObject)
}
})
console.log(newArray)
}
I tried pushing the items to the "number" array on my new object and that doesn't seem to work properly. Sometimes it will duplicate my newObject.name
Checking if the newObject.name === the section_names in the array and push it to the "number" array in my new object just creates new key-value pairs so it's still not correlating.
I tried looping through again in the if statement and if section_name === newObject.name then create a newObject and push it, but it would only push one of the items repeatedly instead of going through all of them.
I need to loop through and create a header (one header per different section_name). Then add each item that corresponds to the section_name to it. like this
[
{section_name(header): "Funds",
items: [
{
name: item_name,
sku: item_sku,
url: item_url
},
{
name: item_name,
sku: item_sku,
url: item_url
}]
},
{section_name(header):"Literature",
items: [
{name: item_name,
sku: item_sku,
url: item_url
},
{
name: item_name,
sku: item_sku,
url: item_url
}]}
]

Using associative array (dictionary) to segregate you data itmes by categories will do the job.
I've drafted some POC code that illustrates the idea. The key element there is buildAssociativeArray function
const raw_data = [
{item_name: "first", section_name: "Funds"},
{item_name: "second", section_name: "Funds"},
{item_name: "third", section_name: "Funds"},
{item_name: "fourth", section_name: "Literature"},
{item_name: "fifth", section_name: "Literature"},
{item_name: "sixth", section_name: "Literature"},
{item_name: "seventh", section_name: "Literature"},
{item_name: "eighth", section_name: "DueDilligence"},
]
function buildAssociativeArray(data) {
const dictionary = {};
for (var i = 0; i < data.length; i++) {
const item = data[i];
const section = item.section_name;
var dictEntry = dictionary[section];
if (!dictEntry) {
dictEntry = [];
dictionary[section] = dictEntry;
}
dictEntry.push({
name: item.item_name,
// other fields like sku: item_sku or url: item_url may follow here
});
}
return dictionary;
}
const dictionary = buildAssociativeArray(raw_data);
console.log(dictionary);
/*
At this point
dictionary == {
"Funds": [
{
"name": "first"
},
{
"name": "second"
},
{
"name": "third"
}
],
"Literature": [
{
"name": "fourth"
},
{
"name": "fifth"
},
{
"name": "sixth"
},
{
"name": "seventh"
}
],
"DueDilligence": [
{
"name": "eighth"
}
]
}
*/
// Associcative array dictionary itself allows to further solve you task using for (var key in dictionary) {...} operator
// If however you need to obtain the data structure looking exactly like the one in your question you may go further with following function
function transformAssociativeArray(dictionary) {
const array = [];
for (var key in dictionary) {
const items = dictionary[key];
const newEntry = {
section_name: key,
items: items,
}
array.push(newEntry);
}
return array;
}
const array = transformAssociativeArray(dictionary);
console.log(array);
/*
At this point
array == [
{
"section_name": "Funds",
"items": [
{
"name": "first"
},
{
"name": "second"
},
{
"name": "third"
}
]
},
{
"section_name": "Literature",
"items": [
{
"name": "fourth"
},
{
"name": "fifth"
},
{
"name": "sixth"
},
{
"name": "seventh"
}
]
},
{
"section_name": "DueDilligence",
"items": [
{
"name": "eighth"
}
]
}
]
*/

Returning an array of objects from other object

Hello am trying to extract some information from an object to create a graph but it returns undefined my object looks like
{
"concepts": [
{
"id_cpt": "1",
"fr_cpt": "Proche",
},
{
"id_cpt": "2",
"fr_cpt": "Loin",
}{
"id_cpt": "3",
"fr_cpt": "Here",
},...
],
"arcs": [
{
"idfrom":"1",
"idto":"2"
},
{
"idfrom":"3",
"idto":"2"
},....
]
}
I want to make an object looks like
const data = {
nodes: [{ id: 'Proche' }, { id: 'Loin' },{ id: 'Here' } ...],
links: [{ source: 'Proche', target: 'Loin' }, { source: 'Here', target: 'Loin' },...]
};
I want extract names not ids in links but the object arcs only have ids the code in es6 and thank you for helping me

You could loop through the concepts using for...of. Populate the nodes array and a map object. The map object has id_cpt as key and fr_cpt as value.
{
"1": "Proche",
"2": "Loin",
"3": "Here"
}
This object can be used to get the source and target value for links. Then loop through arcs and create links using map object
Here's a snippet:
const input = {"concepts":[{"id_cpt":"1","fr_cpt":"Proche",},{"id_cpt":"2","fr_cpt":"Loin",},{"id_cpt":"3","fr_cpt":"Here",},],"arcs":[{"idfrom":"1","idto":"2"},{"idfrom":"3","idto":"2"},]}
let nodes = [],
links = [],
map = {};
for (const { id_cpt, fr_cpt } of input.concepts) {
nodes.push({ id: fr_cpt });
map[id_cpt] = fr_cpt
}
for (const { idfrom, idto } of input.arcs) {
links.push({ source: map[idfrom], target: map[idto] }) // get the value using map
}
const output = { nodes, links }
console.log(output)

Angular bind to filtered count

I have this array:
[
{
type: "hhh",
items: [
{
"name": "EGFR",
"type": "a",
"selected": true
}
]
},
{
type: "aaa",
items: [
{
"name": "mm",
"type": "b",
"selected": false
}
]
},
{
type: "ii",
items: [
{
"name": "pp",
"type": "bb",
"selected": true
}
]
}
]
I want to show a counter of the items with selected property "true".
I want it to be changed real time when change.
(Without watch and function)
Thnaks!

Here is the way:
var current_selected = {
get amount(){
var res = 0;
arr.forEach(function(item, i, arr) {
if (item.items[0].selected) res++;
})
return res;
}
}
Calling:
current_selected.amount
Fiddle

You can use JsonPath to get the count. Also using JsonPath has an added advantage of working on complex json structure. For the example you gave, you just need to include jsonpath js file and use the following in your script:
console.log(arr);
var filtered = jsonPath(arr, "$.[*].items[?(#.selected==true)]");
console.log(filtered);
console.log(filtered.length);
where arr is your json structure.
JsonPath can be got from :
https://code.google.com/archive/p/jsonpath/downloads
JsonPath help:
http://goessner.net/articles/JsonPath/
There might be updated version in other sources but that was the one I had worked on