zetabasejs/libs/dataStructures/DataNode.js

A NoSQL database for quick deployment.

const crypto = require("crypto");
const NodePtr = require("./NodePtr");
const Stack = require("./Stack");
const Deprecator = require("../Deprecator");

class DataNode {
    constructor(id, data) {
        this.id = id;
        this.data = data ? data : null;
        this.childNodes = new Object();
    }

    add(id, data) {
        this.childNodes[id] = new DataNode(id, data);
        return this;
    }

    push(data) {
        let id = DataNode.key();
        this.childNodes[id] = new DataNode(id, data);
        return id;
    }

    get(id) {
        return this.childNodes[id];
    }

    remove(id) {
        this.childNodes[id] = null;
        delete this.childNodes[id];
    }

    has(id) {
        return this.childNodes.hasOwnProperty(id);
    }

    static keyPrefix(prefix="ZETABASE_KEY") {
        return crypto.createHash("md5").update(prefix).digest('base64').substr(0, 5).toString('hex')
    }

    static key() {
        return crypto.createHash("md5").update(new Date().getTime() + Math.random().toString()).digest("hex") + DataNode.keyPrefix();
    }

    list(callback) {
        Object.keys(this.childNodes).map(childNodeKey =>
            callback(
                this.childNodes[childNodeKey].data,     //data
                childNodeKey,                           //key
                this.childNodes[childNodeKey]           //dataNode
            )
        )
    }

    childKeys() {
        return Object.keys(this.childNodes);
    }

    traverse(id) {
        let cur = this;
        let next = this.childNodes[id];
        return new NodePtr(cur, next);
    }

    size() {
        return Object.keys(this.childNodes).length;
    }

    isEmpty() {
        return this.data === null && this.size() === 0;
    }

    static fromObject(obj) {
        let dataNode = new DataNode("/", null);
        if (obj.hasOwnProperty("data")) dataNode.data = obj.data;
        if (obj.childNodes)
            Object.keys(obj.childNodes).map((childNodeKey) => {
                dataNode.childNodes[childNodeKey] = DataNode.fromObject(obj.childNodes[childNodeKey]);
            })
        return dataNode;
    }

    /*
        The below functions are deprecated.
    */
    iterate(callback) {
        Object.keys(this.childNodes).map(childNodeKey =>
            callback(
                childNodeKey,                           //key
                this.childNodes[childNodeKey].data,     //data
                this.childNodes[childNodeKey]           //dataNode
            )
        )
    }
}
module.exports = DataNode;