ready-primes-extended/src/helpers/JsonHelper.ts

Get Primes in milliseconds. Pre-calculated collections of prime numbers, natural numbers with distinguished primes and methods to retrieve them.

/// <reference path="../../typings/jsonfile.d.ts" />

import * as path from 'path';
import * as jsonfile from 'jsonfile';
import * as fsExtra from 'fs-extra';
import * as Promise from 'bluebird';
import * as _each from 'lodash/each';

export class JsonHelper {

    static INTEGER_EXT: string = '.int';
    static PRIME_EXT: string = '.prime';
    static DATA_PATH: string = path.resolve(__dirname, '../../data');

    static read(filename: string | number): Promise<any> {
        return new Promise((resolve: Function, reject: Function) => {
            jsonfile.readFile(`${JsonHelper.DATA_PATH}/${filename}`, {}, (err: any, chunk: number[]) => {
                if (err) {
                    reject(err);
                } else {
                    resolve(chunk);
                }

            });
        });
    }

    static write(filename: string | number, data: any): Promise<any> {
        return new Promise((resolve: Function, reject: Function) => {
            jsonfile.writeFile(`${JsonHelper.DATA_PATH}/${filename}`, data, {}, (err: any) => {
                if (err) {
                    console.log(err);
                    reject(false);
                } else {
                    resolve(true);
                }
            });
        });
    }

    static readIntegerFile(filename: string | number): Promise<any> {
        return JsonHelper.read(filename + JsonHelper.INTEGER_EXT);
    }

    static readMultipleIntegerFiles(filenames: number[] | string[]): Promise<any> {
        let promises: Promise<any>[] = [];
        _each(filenames, (filename: number | string) => {
            promises.push(JsonHelper.readIntegerFile(filename));
        });
        return Promise.all(promises);
    }

    static writeIntegerFile(filename: string | number, data: any): Promise<any> {
        return JsonHelper.write(filename + JsonHelper.INTEGER_EXT, data);
    }

    static readPrimeFile(filename: string | number): Promise<any> {
        return JsonHelper.read(filename + JsonHelper.PRIME_EXT);
    }

    static readMultiplePrimeFiles(filenames: number[] | string[]): Promise<any> {
        let promises: Promise<any>[] = [];
        _each(filenames, (filename: number | string) => {
            promises.push(JsonHelper.readPrimeFile(filename));
        });
        return Promise.all(promises);
    }

    static writePrimeFile(filename: string | number, data: any): Promise<any> {
        return JsonHelper.write(filename + JsonHelper.PRIME_EXT, data);
    }

    static writeReference(data: any): void {
        const referencePath: string = `${JsonHelper.DATA_PATH}/reference.js`;
        const referenceData: string = 'exports.reference = ' + JSON.stringify(data);

        fsExtra.outputFile(referencePath, referenceData);
    }

}