Docker on AWS CodeDeploy

Deploying a Middleman site as a Docker container built with CircleCI and AWS CodeDeploy to a highly available cluster. Whoa, that was a mouthful. Basically, we are mashing up these services and applications:

• Docker
• Middleman
• CircleCI
• AWS

Still interested? Cool! Let's get to it...

Setup

First things first, I make some assumptions in this article:

• You are already setup with AWS and are comfortable with IAM and policies.
• You have used or are interested in using CircleCI.
• You know a little bit about Middleman and maybe even have a Ruby environment available locally.
• You like fiddling with things.

Application

• In the AWS CodeDeploy console, create a new application. We're going to use the name middleman for both the Application Name and the Deployment Group Name.
• Under Search by Amazon EC2 Tags select the Name key and fill in middleman. We'll create these instances soon.
• Deployment Config can be OneAtATime.
• Service Role ARN* should be the Service Role you already created in the setup.

Now you can click the Create Application button. Cool. We have an application!

Instances

Now lets move over to the CloudFormation console so we can create our middleman stack.

• Click the Create Stack button near the top left of the page.
• We are going to use the name middleman.
• The template to upload is the aws/codedeploy_docker_cf_template.json file in this repository.
• Set Instance Count to 3.
• Set Key Pair to an actual key pair name in AWS already.
• Make sure TagKey is Name and set TagValue to middleman (the tag our CodeDeploy Deployment Group will look for).

Create the stack. Kewl.

Bucket

Move over to the S3 console and create a bucket.

• Click the blue Create Bucket button.
• We are using the bucket named andyshinn-middleman in this example.

Deploy

When you commit and push code to your repository the following will now happen:

• Our Middleman application Docker image gets built.
• We run the image to generate a Middleman site as build.tar.gz.
• We then copie build.tar.gz out of the container and into images/nginx.
• Now we build the images/nginx image as middleman.
• We then export the middleman image as middleman_docker_image.tar.gz.
• The CodeDeploy revision is kicked off and our application is pushed as a zip file to our S3 bucket.
• A CodeDeploy deployment of this revision is run for our server group.