build-hierarchy
Advanced tools
Convert flat structures to deeply nested hierarchical data in node.js. Transform flat objects array representations to array of nested objects.
Convert flat structures to deeply nested hierarchical data in node.js. Transform flat objects array representations to array of nested objects.
Basic usage example:
> npm install build-hierarchy -S
const HierarchyBuilder = require('build-hierarchy');
//Optionally required to view result.
const fs = require('fs');
const util = require('util');
/*
Taking input an array of flat structure
and returning hierarichal data as an output.
example :
input : [continent, country, state, city]
output : coninent -> country -> state -> city
*/
//Input flat structure.
const input = [
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 101,
"Country": "India",
"State_ID": 1001,
"State": "Gujrat",
"City_ID": 10001,
"City": "Surat"
},
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 101,
"Country": "India",
"State_ID": 1001,
"State": "Gujrat",
"City_ID": 10002,
"City": "Rajkot"
},
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 101,
"Country": "India",
"State_ID": 1002,
"State": "Haryana",
"City_ID": 10003,
"City": "Gurugram"
},
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 101,
"Country": "India",
"State_ID": 1002,
"State": "Haryana",
"City_ID": 10004,
"City": "Panipat"
},
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 102,
"Country": "Thailand",
"State_ID": 1003,
"State": "Chiang Mai",
"City_ID": 10005,
"City": "Doi Saket"
},
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 102,
"Country": "Thailand",
"State_ID": 1003,
"State": "Chiang Mai",
"City_ID": 10006,
"City": "Chom Thong"
},
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 102,
"Country": "Thailand",
"State_ID": 1004,
"State": "Chiang Rai",
"City_ID": 10007,
"City": "Mae Suai"
},
{
"Continent_ID": 1,
"Continent": "Asia",
"Country_ID": 102,
"Country": "Thailand",
"State_ID": 1004,
"State": "Chiang Rai",
"City_ID": 10008,
"City": "Phan"
},
{
"Continent_ID": 2,
"Continent": "Africa",
"Country_ID": 107,
"Country": "South Africa",
"State_ID": 1005,
"State": "Northern Cape",
"City_ID": 10009,
"City": "Kimberley"
},
{
"Continent_ID": 2,
"Continent": "Africa",
"Country_ID": 107,
"Country": "South Africa",
"State_ID": 1005,
"State": "Northern Cape",
"City_ID": 10010,
"City": "Sutherland"
},
{
"Continent_ID": 2,
"Continent": "Africa",
"Country_ID": 107,
"Country": "South Africa",
"State_ID": 1006,
"State": "Eastern Cape",
"City_ID": 10011,
"City": "Stormsrivier"
},
{
"Continent_ID": 2,
"Continent": "Africa",
"Country_ID": 107,
"Country": "South Africa",
"State_ID": 1006,
"State": "Eastern Cape",
"City_ID": 10012,
"City": "Hogsback"
},
{
"Continent_ID": 3,
"Continent": "North America",
"Country_ID": 112,
"Country": "Canada",
"State_ID": 1007,
"State": "Ontario",
"City_ID": 10013,
"City": "Toronto"
},
{
"Continent_ID": 3,
"Continent": "North America",
"Country_ID": 112,
"Country": "Canada",
"State_ID": 1007,
"State": "Ontario",
"City_ID": 10014,
"City": "Ottawa"
},
{
"Continent_ID": 3,
"Continent": "North America",
"Country_ID": 112,
"Country": "Canada",
"State_ID": 1008,
"State": "Quebec",
"City_ID": 10015,
"City": "Montreal"
},
{
"Continent_ID": 3,
"Continent": "North America",
"Country_ID": 112,
"Country": "Canada",
"State_ID": 1008,
"State": "Quebec",
"City_ID": 10016,
"City": "Sherbrooke"
}
]
//Defining levels and properties to be used.
const levels = [
{
"level": 1,
"groupByKeys": ["Continent_ID"], //can be grouped by multiple properties.
"entities": [
{
"id": 1,
"name": "Continent",
"properties": {
"Continent_ID": "id", //property name alias.
"Continent": "name"
}
}
]
},
{
"level": 2,
"groupByKeys": [
"Country_ID"
],
"entities": [
{
"id": 1,
"name": "Country",
"properties": {
"Country_ID": "id",
"Country": "name"
}
}
]
},
{
"level": 3,
"groupByKeys": [
"State_ID"
],
"entities": [
{
"id": 1,
"name": "State",
"properties": {
"State_ID": "id",
"State": "state"
}
}
]
},
{
"level": 4,
"groupByKeys": ["City_ID"],
"entities": [
{
"id": 1,
"name": "City",
"properties": {
"City_ID": "id",
"City": "name"
}
}
]
}
];
const builder = new HierarchyBuilder();
const resultset = builder.buildHierarchy(input, levels);
//Using util.inspect method to see depply nested data.
console.log(util.inspect(resultset, { showHidden: false, depth: null, colors: true }))
//To view better logging resultset to a JSON file.
fs.writeFile("resultset.json", JSON.stringify(resultset), err => {
if (err) throw err;
console.log("Done writing resultset.json");
});
//Output :
/*
[
{
"id": 1,
"name": "Asia",
"children": [
{
"id": 101,
"name": "India",
"children": [
{
"id": 1001,
"state": "Gujrat",
"children": [
{
"id": 10001,
"name": "Surat",
"children": []
},
{
"id": 10002,
"name": "Rajkot",
"children": []
}
]
},
{
"id": 1002,
"state": "Haryana",
"children": [
{
"id": 10003,
"name": "Gurugram",
"children": []
},
{
"id": 10004,
"name": "Panipat",
"children": []
}
]
}
]
},
{
"id": 102,
"name": "Thailand",
"children": [
{
"id": 1003,
"state": "Chiang Mai",
"children": [
{
"id": 10005,
"name": "Doi Saket",
"children": []
},
{
"id": 10006,
"name": "Chom Thong",
"children": []
}
]
},
{
"id": 1004,
"state": "Chiang Rai",
"children": [
{
"id": 10007,
"name": "Mae Suai",
"children": []
},
{
"id": 10008,
"name": "Phan",
"children": []
}
]
}
]
}
]
},
{
"id": 2,
"name": "Africa",
"children": [
{
"id": 107,
"name": "South Africa",
"children": [
{
"id": 1005,
"state": "Northern Cape",
"children": [
{
"id": 10009,
"name": "Kimberley",
"children": []
},
{
"id": 10010,
"name": "Sutherland",
"children": []
}
]
},
{
"id": 1006,
"state": "Eastern Cape",
"children": [
{
"id": 10011,
"name": "Stormsrivier",
"children": []
},
{
"id": 10012,
"name": "Hogsback",
"children": []
}
]
}
]
}
]
},
{
"id": 3,
"name": "North America",
"children": [
{
"id": 112,
"name": "Canada",
"children": [
{
"id": 1007,
"state": "Ontario",
"children": [
{
"id": 10013,
"name": "Toronto",
"children": []
},
{
"id": 10014,
"name": "Ottawa",
"children": []
}
]
},
{
"id": 1008,
"state": "Quebec",
"children": [
{
"id": 10015,
"name": "Montreal",
"children": []
},
{
"id": 10016,
"name": "Sherbrooke",
"children": []
}
]
}
]
}
]
}
]
*/
[MIT License] © Ayush Pratap
FAQs
Convert flat structures to deeply nested hierarchical data in node.js. Transform flat objects array representations to array of nested objects.
We found that build-hierarchy demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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