Description

Codedeployer is a small library that helps deploying any application or codebase to groups of ec2 instances through AWS Codedeploy. The deploy process needs pre-configuration on the AWS side, so ask your nearest ops.

The deployment works like this:

• an archive is created containing the codebase and a special appspec.yml file needed by Codedeploy
• this archive is uploaded to S3
• a series of calls is made to the Codedeploy API to initiate deployments
• an agent installed on all supported instances polls Codedeploy waiting for deployment instructions
• when the agent receives a deployment instruction, it downloads the archive from S3 and executes the steps defined in the appspec.yml file

This process shifts the deployment from a push system like Idephix or Deployer that requires ssh access to machines in order to rsync the code, to a poll system where the instances are notified of a new deployment request by the agent and download the application archive, running all the configured scripts to complete the deployment.

Installation and usage

1. Run composer require mriva/codedeployer
2. Run bin/deploy --setup
3. Create directories named as deployment groups
4. Add scripts inside deployment groups directories
5. Compile config.php
6. Run bin/deploy

Point 1 and 2 are self explanatory.

Point 3 requires you to create a directory under deploy/hook-script for each instance group you want to deploy to. For example, if you wish to deploy to alfa and beta instance groups, the tree will look like this:

deploy/
└── hook-scripts/
    ├── ec2-alfa/
    └── ec2-beta/

Point 4 requires you to populate the directories from point 3. AWS Codedeploy offers various hooks during the process, for simplicity the default setup only uses AfterInstall but other hooks can be easily added to appspec.yml if needed.

AfterInstall is the first hook available and is run after the agent has downloaded and extracted the revision archive to a temporary directory; it is used to actually copy all the code to the real target directory and execute any post-install script that might be needed (ie. clearing cache, recreating snapshots, etc).

For more information on AWS Codedeploy hooks see: https://docs.aws.amazon.com/codedeploy/latest/userguide/reference-appspec-file-structure-hooks.html#appspec-hooks-server

Now add scripts in those directories named after these hooks, so assuming you go for the easy version with just AfterInstall, your tree should look like this:

deploy/
└── hook-scripts/
    ├── ec2-alfa/
    │   └── AfterInstall.sh
    └── ec2-beta/
        └── AfterInstall.sh

these script will be run by the main hook-wrapper.sh which is defined as the main hook in appspec.yml

There are two example scripts ready to be used with minimal configuration for simple copy and rotating releases deploy in the config/hook-scripts/example-scripts/ directory.

Point 5 only requires you to compile a few application related options, the file should be self explanatory as well.

TODO

• refactor config.php with some other form of configuration
• write Codedeploy new activation (app + groups) through CLI skipping web console
• sanity checks