Lab2 : NodeJS

app.mjs

import { Emitter } from "./constructorFunction.mjs"

let emit = new Emitter();
emit.on("login",function(){
    console.log("hello you are logged in");
})

emit.emit("login")

constructorFunction.mjs

export function Emitter() {
    this.events = {}
}

Emitter.prototype.on = function (type, listener) {
    this.events[type] = this.events[type] || [];
    this.events[type].push(listener)
}

Emitter.prototype.emit = function(type){
    if(this.events[type]){
        this.events[type].forEach(function (listener){
            listener()
        })
    }
}

fileHandleByLine.mjs

/*
* ================================================================
* =========================== File Handle ========================
* ================================================================
* */

import  readLine  from "readline";
import  fs from "fs";
let fileHandle = readLine.createInterface({
    input: fs.createReadStream(new URL("greet.text",import.meta.url)),
    output: process.stdout
})

fileHandle.on("line",()=>{
    console.log("**************************************************");
})

files.mjs

/*
* ================================================================
* ===================== Files With NodeJS ========================
* ================================================================
* */


/*
* ================================================================
* ========================== Async Method ========================
* ================================================================
* */
import { readFile,writeFile } from "fs/promises";

let fileData = await readFile(new URL("data.json", import.meta.url), 'utf-8');

console.log(fileData)

/*
* ================================================================
* ========================== sync Method =========================
* ================================================================
* */
import fs from "fs";

fs.readFile(new URL("data.json", import.meta.url),'utf-8' ,(error,data) => {
    if (error) {
        console.error(error);
        return error;
    } else {
        console.log(data);
        // console.log(data.toString())
    }
})

/*
* ================================================================
* ========================== Rename File =========================
* ================================================================
* */

fs.rename("test.txt","info.txt",()=>{
    console.log("file name changed!")
})
/*
* ================================================================
* ========================== remove file =========================
* ================================================================
* */

fs.unlink("./test1.txt",()=>{
    console.log("file removed");
})

/*
* ================================================================
* ========================= Write to file ========================
* ================================================================
* */
await writeFile("info.txt","Hello iti (Hegabovic)","utf-8");

// create a directory
fs.mkdir("./NewDirectory",null,(error)=>{
    if(error){
        console.error(error);
        return error;
    } else{
        console.log("directory has been created successfully");
    }
})