Building and publishing a Docker image to ECR using GitHub Actions

GitHub Actions provides a framework for integrating DevOps processes into any GitHub repository by using workflows, enabling interactions with various services during deployment. This guide details the process of building and pushing the Octopus Deploy underwater app to Amazon Elastic Container Registry (ECR) through GitHub Actions. To follow along, users need an AWS account, a GitHub account, and access to the Octopus underwater app repository. The setup involves creating an access key and an ECR repository in AWS, configuring GitHub secrets for authentication, and creating a workflow file that outlines the steps for deploying the app. The workflow involves checking out the code, authenticating with AWS, and using pre-built step templates to build, tag, and push the Docker image to Amazon ECR. The guide shows how GitHub Actions automatically triggers these steps upon pushes or pull requests to the main branch, and discusses the potential for similar workflows to deploy to other cloud services. The post concludes by mentioning future topics, such as deploying the app to Amazon EKS using GitHub Actions and Octopus Deploy, and offers resources for learning more about these tools.