@zaki-fr/decision-tree-json

A decision-tree library that works with JSON files database

BUILD SOURCE

This section describes some hints for developer who want to contribute to this library.

Get Sourcecode

git clone https://github.com/zaki-fr/decision-tree-json.git

Install Dependancies

npm install

Create JSON database database-path/new-db.json file

{
    "key": "ROOT",
    "title": "A decision tree demonstration",
    "options": [
      {
        "key": "STATIC-NODE",
        "label": "A static traversal node option",
        "leadsTo": "STATIC-28"
      },
      {
        "key": "RULE-NODE",
        "label": "A node with dynamic rule option",
        "script": "params => params.age > 28 ? 'OVER-28': 'UNDER-28'"
      }
    ],
    "children": [
      {
        "label": "A static node with children nodes",
        "key": "STATIC-28",
        "options": [ {other-options} ],
        "children": [ {other-nodes} ]
      },
      {
        "label": "A node with age > 28",
        "key": "OVER-28"
      },
      {
        "label": "A node with age under 28",
        "key": "UNDER-28"
      }
    ]
}

Create Test Spec new-db.spec.js

import DecisionTree from "@zaki-fr/decision-tree-json"
import assert from 'assert'

describe('Test `new-db` database', function() {
    var decisionTree = null
    var root = null
    beforeEach(function() {
        decisionTree = new DecisionTree(
            __dirname + "/database-path",
            "new-db.json"
        )
        root = decisionTree.current()
    });
    it('should return STATIC-28 node as you expected', function() {
        var result = decisionTree.set(root.key, 'STATIC-28').next()
        assert.equal(result.key, 'STATIC-28')
    });
})

Test Engine/Database

npm test

Test Library Usage

npm run dev

HOW TO USE

This section describes for community users who want to use this library into their applications.

Create JSON database structure ROOT.json

{
    "key": "ROOT",
    "title": "A decision tree demonstration",
    "options": [
      {
        "key": "STATIC-NODE",
        "label": "A static traversal node option",
        "leadsTo": "STATIC-28"
      },
      {
        "key": "RULE-NODE",
        "label": "A node with dynamic rule option",
        "script": "params => params.age > 28 ? 'OVER-28': 'UNDER-28'"
      }
    ],
    "children": [
      {
        "label": "A referenced database as `STATIC-28.json` file",
        "ref": "STATIC-28"
      },
      {
        "label": "A node with age > 28",
        "key": "OVER-28"
      },
      {
        "label": "A node with age under 28",
        "key": "UNDER-28"
      }
    ]
}

Load DecisionTree module using native Javascript

const DecisionTree = require("@zaki-fr/decision-tree-json").default
const decisionTree = new DecisionTree(__dirname + "/database", "ROOT.json")

Load DecisionTree module using ECMASCRIPT 6 (ES6) or TypeScript

import DecisionTree from "@zaki-fr/decision-tree-json"
const decisionTree = new DecisionTree(__dirname + "/database", "ROOT.json")

Set tree node position ROOT and option value STATIC-28

decisionTree.set('ROOT', 'STATIC-28').next()

Note: STATIC-28 node is an extended database stored in STATIC-28.json file at the same location with the main database ROOT.json in folder __dirname + "/database"

Get current navigated node from previous step

var result = decisionTree.current()
console.log(result)

Node traversal rule with dynamic decision:

• Traveral parameters { age: 30 }
• For node.options.script "script": "params => params.age > 28 ? 'OVER-28' : 'UNDER-28'"

decisionTree.set('ROOT', 'RULE-NODE').next({ age: 30 })

Back to previous node position

decisionTree.prev()
var result = decisionTree.current()
console.log(result)

Print navigated nodes by keys

var result = decisionTree.history()
console.log(result)

Print navigated options by keys

var result = decisionTree.journey()
console.log(result)

Get all leafs from the current node

var result = decisionTree.lastleafs()
console.log(result)