Sample

This is the follow along repository for my "Blue Green Deployment with Nginx for Elixir/Phoenix Release" article.

The script used here is the final script from the blog post. Hence, if you want to follow stage by stage according to the post, consider removing deploy.sh.

The instructons here currently only cover the final usage of the deploy script and some of the setup needed to follow along.

Vagrant

The Vagrant virtual machine is setup with the following:

• Nginx
  • Remove default configuration.
• PostgreSQL
  • Create sample_prod database.
  • Create sample_app user.

Instructions

1. Setup your virtual machine (VM) locally with Vagrant by running the following:

   cd vagrant
   vagrant up

   By the end of the command, you should be able to ssh into the vagrant VM by vagrant ssh.

2. To enable yourself to be able to ssh to the Vagrant VM through ssh vagrant@192.168.33.40, you'll need to manually copy your public key to the Vagrant VM.

   # Or any equivalent public key file path
   # pbcopy only works in MacOS, for Ubuntu or Windows
   # user, just copy the public key manually after cat.
   cat ~/.ssh/id_rsa.pub | pbcopy
   
   # Don't copy the code below if you just run pbcopy above.
   vagrant ssh
   cat >> ~/.ssh/authorized_keys << EOF
   # Paste your public key here
   EOF

3. If you are following along the post, you could also add the following line to your /etc/hosts file (you'll need sudo access to change /etc/hosts`):

   192.168.33.40 domain.app
   

4. If you are following along the post, it assume that you have deployed your application to the remote server. You can do that first by:

   ./deploy.sh
   
   # After deployed
   ssh vagrant@192.168.33.40
   curl localhost:4000/health
   #=> {"healthy":true,"version":"0.1.0"}

5. Now you can follow along on the blog post by proceeding to setup the nginx configuration.

6. Deploying green version of our application:

   git apply change_01.diff
   ./deploy.sh

7. Promoting our green version to live:

   ./deploy.sh promote green
   # ---> Attempting to promote to green...
   # ---> Promoted live to blue
   
   # Wait 1-2 seconds
   curl domain.app/health
   #=> {"healthy":true,"version":"0.1.1"}

8. Running migration:

   # ./deploy.sh migrate <green | blue | default to live version>
   ./deploy.sh migrate
   

9. For deploying subsequent blue/green version, feel free to change the code around or by bumping the version in mix.exs and deploy through the script.

10. After finishing, You can destory the Vagrant VM by running vagrant destroy in the vagrant directory.