Jozef Butko jbutko

HTTPS setup on Nginx server with Let's Encrypt

download certbot tool: sudo git clone https://github.com/certbot/certbot /opt/certbot
generate certs: sudo /opt/certbot/certbot-auto --nginx
in the menu select domain for which you want to generate SSL certs
in next menu select if you want http && https access to your site or https exclusively

That's all, your site is now running under https.

If you want to make https connection more secure generate 4096 DHA key (could take almost 20 minutes):

create new file: sudo nano /etc/nginx/sites-available/mysite.com.conf and add:

server {            
        # on which port should nginx listen
        listen 80 default_server;                                                                                                     
        listen [::]:80 default_server;                                                                                                
                                        
        # serve client
        root /home/ionic-app/client/www;                                                                               
        index index.html index.htm;

create and paste public key (id_xsa.pub) into authorized_keys

nano ~/.ssh/authorized_keys

set permission of authorized_keys to 600

chmod 600 ~/.ssh/authorized_keys

set permission of .ssh folder to 700

chmod 700 ~/.ssh/

via https://askubuntu.com/questions/46424/adding-ssh-keys-to-authorized-keys#answer-46425

When you run an app in cluster mode with PM2 each worker will receive a value in process.env.NODE_APP_INSTANCE which goes from 0 to number of workers-1. Let's say you start your app with pm2 start app.js -i 4, then your workers will receive 0 1 2 3 as NODE_APP_INSTANCE value.

Then in your code you can use that value to set the listen port such as server.listen(8000 + process.env.NODE_APP_INSTANCE)

// Unitech/pm2#1510 (comment)

// pm2 user permission fix Unitech/pm2#837

create SSH keys

ssh-keygen -t rsa -b 4096 -C "[email protected]"

assign public key (id_rsa.pub from ssh-rsa to end of your email) to gitlab project on https://gitlab.com/username/projectname/settings/repository in Create a new deploy key for this project

cat ~/.ssh/id_rsa.pub

more on: https://docs.gitlab.com/ce/ssh/README.html

create ssh command alias

Host project.stage
  HostName stage.project.com
  User webadmin
  Port 2222

Send to the sender and noone else

socket.emit('hello', msg);

Send to everyone including the sender(if the sender is in the room) in the room "my room"

io.to('my room').emit('hello', msg);

Send to everyone except the sender(if the sender is in the room) in the room "my room"

socket.broadcast.to('my room').emit('hello', msg);

	# -n number of request to test
	# -c number of concurrent requests
	# -H authorization header
	ab -n 1000 -c 1000 -H "Authorization: someBearerToken" http://localhost:5000/api/v1/someEndpoint

	# via https://www.petefreitag.com/item/689.cfm

	#!/bin/bash

	MONGO_DATABASE="your_db_name"
	APP_NAME="your_app_name"

	MONGO_HOST="127.0.0.1"
	MONGO_PORT="27017"
	TIMESTAMP=`date +%F-%H%M`
	MONGODUMP_PATH="/usr/bin/mongodump"
	BACKUPS_DIR="/home/username/backups/$APP_NAME"

	const crypto = require('crypto');
	const id = crypto.randomBytes(24).toString('hex');

	// via http://stackoverflow.com/questions/23327010/how-to-generate-unique-id-with-node-js#answer-40191779