paulfranco

Interview Questions

Node.js

Q1: What do you mean by Asynchronous API? ☆☆

Answer: All APIs of Node.js library are aynchronous that is non-blocking. It essentially means a Node.js based server never waits for a API to return data. Server moves to next API after calling it and a notification mechanism of Events of Node.js helps server to get response from the previous API call.

Source: tutorialspoint.com

parmentf

Inspired by dannyfritz/commit-message-emoji

See also gitmoji.

Commit type	Emoji
Initial commit	🎉 :tada:
Version tag	🔖 :bookmark:
New feature	✨ :sparkles:
Bugfix	🐛 :bug:

alexpchin

#Adding an existing project to GitHub using the command line

Simple steps to add existing project to Github.

1. Create a new repository on GitHub.

In Terminal, change the current working directory to your local project.

##2. Initialize the local directory as a Git repository.

git init

Andrey2G

ffmpeg -i "c:/videos/sample.mp4
-map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0
-c:v libx264 -crf 22 -c:a aac -ar 48000
-filter:v:0 scale=w=480:h=360  -maxrate:v:0 600k -b:a:0 64k 
-filter:v:1 scale=w=640:h=480  -maxrate:v:1 900k -b:a:1 128k 
-filter:v:2 scale=w=1280:h=720 -maxrate:v:2 900k -b:a:2 128k 
-var_stream_map "v:0,a:0,name:360p v:1,a:1,name:480p v:2,a:2,name:720p"
-preset slow -hls_list_size 0 -threads 0 -f hls -hls_playlist_type event -hls_time 3
-hls_flags independent_segments -master_pl_name "name-pl.m3u8"
"c:/videos/encoded/name-%v.m3u8"                    

Chaser324

Whether you're trying to give back to the open source community or collaborating on your own projects, knowing how to properly fork and generate pull requests is essential. Unfortunately, it's quite easy to make mistakes or not know what you should do when you're initially learning the process. I know that I certainly had considerable initial trouble with it, and I found a lot of the information on GitHub and around the internet to be rather piecemeal and incomplete - part of the process described here, another there, common hangups in a different place, and so on.

In an attempt to coallate this information for myself and others, this short tutorial is what I've found to be fairly standard procedure for creating a fork, doing your work, issuing a pull request, and merging that pull request back into the original project.

Creating a Fork

Just head over to the GitHub page and click the "Fork" button. It's just that simple. Once you've done that, you can use your favorite git client to clone your repo or j

bradtraversy

Node.js Deployment

Steps to deploy a Node.js app to DigitalOcean using PM2, NGINX as a reverse proxy and an SSL from LetsEncrypt

1. Sign up for Digital Ocean

If you use the referal link below, you get $10 free (1 or 2 months) https://m.do.co/c/5424d440c63a

2. Create a droplet and log in via ssh

I will be using the root user, but would suggest creating a new user

joshnuss

// the main app file
import express from "express";
import loadDb from "./loadDb"; // dummy middleware to load db (sets request.db)
import authenticate from "./authentication"; // middleware for doing authentication
import permit from "./authorization"; // middleware for checking if user's role is permitted to make request

const app = express(),
      api = express.Router();

// first middleware will setup db connection

crtr0

// set-up a connection between the client and the server
var socket = io.connect();

// let's assume that the client page, once rendered, knows what room it wants to join
var room = "abc123";

socket.on('connect', function() {
   // Connected, let's sign-up for to receive messages for this room
   socket.emit('room', room);
});

umidjons

Sort object properties by value (values are text)

I have following object:

var cities={10:'Tashkent', 14:'Karakalpakiya', 16:'Andijan'};

I want sort it by city names, so after sort it should be:

var cities={16:'Andijan', 14:'Karakalpakiya', 10:'Tashkent'};

But I can't sort object properties, instead can convert object into array, then sort items.

everget

JavaScript Bitwise Hacks

It assumes the highest positive signed 32-bit float value for numbers. In other words, 2147483647 (or 0x7FFFFFFF or 2^31-1).

Table of Contents

1. Toggle switch
2. Variable swap
3. Math.pow
4. Determine if an integer is a power of 2
5. Round up to the next highest power of 2