learneriq

set -e, -u, -x, -o pipefail

The set lines

• These lines deliberately cause your script to fail. Wait, what? Believe me, this is a good thing.
• With these settings, certain common errors will cause the script to immediately fail, explicitly and loudly. Otherwise, you can get hidden bugs that are discovered only when they blow up in production.

• set -euxo pipefail is short for:

set -e
set -u

learneriq

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

Sometimes we need to run multiple nodejs app on same server with different domain or sub domain like admin.domain.com, api.domain.com and also need to run both nodejs or reactjs app concurrently. We can do this using 2 things , first of all we need to install nginx in our server for reverse proxy to connect different domain, and for running multiple nodejs app concurrently we can use PM2 NodeJs Process Manager

Please Make sure that you have installed these things on your server

• NodeJS

learneriq

# Count total EBS based storage in AWS
aws ec2 describe-volumes | jq "[.Volumes[].Size] | add"
# Count total EBS storage with a tag filter
aws ec2 describe-volumes --filters "Name=tag:Name,Values=CloudEndure Volume qjenc" | jq "[.Volumes[].Size] | add"
# Describe instances concisely
aws ec2 describe-instances | jq '[.Reservations | .[] | .Instances | .[] | {InstanceId: .InstanceId, State: .State, SubnetId: .SubnetId, VpcId: .VpcId, Name: (.Tags[]|select(.Key=="Name")|.Value)}]'
# Wait until $instance_id is running and then immediately stop it again
aws ec2 wait instance-running --instance-id $instance_id && aws ec2 stop-instances --instance-id $instance_id

# Get 10th instance in the account