Deploying Go Applications to AWS App Runner
By: Date: 10/03/2023 Categories: AWS Tags:

AWS App Runner simplifies the process of deploying new versions of their code or image repository. They can easily push their code to the repository, and App Runner will automatically take care of the deployment process. On the other hand, for operations teams, App Runner allows for automatic deployments every time a new commit is pushed to the code repository or a new container image version is added to the image repository.

Overview: App Runner Service

App Runner: Service Sources

With AWS App Runner, you can create and manage services based on two types of service sources:

  • Source code (covered in this blog post)
  • Source image

Source code is nothing but your application code that App Runner will build and deploy. All you need to do is point App Runner to a source code repository and choose a suitable runtime that corresponds to a programming platform version. App Runner provides platform-specific managed runtimes (for Python, Node.js, Java, Go, etc.).

The AWS App Runner Go platform runtime makes it easy to build and run containers with web applications based on a Go version. You don’t need to provide container configuration and build instructions such as a Dockerfile. When you use a Go runtime, App Runner starts with a managed Go runtime image which is based on the Amazon Linux Docker image and contains the runtime package for a version of Go and some tools. App Runner uses this managed runtime image as a base image and adds your application code to build a Docker image. It then deploys this image to run your web service in a container.

Let’s Get Started

Make sure you have an AWS account and install AWS CLI.

1. Create a GitHub Repo for the URL Shortener Application

Clone this GitHub repo and then upload it to a GitHub repository in your account (keep the same repo name i.e. apprunner-go-runtime-app):

git clone https://github.com/abhirockzz/apprunner-go-runtime-app

2. Create a DynamoDB Table To Store URL Information

Create a table named urls. Choose the following:

  • Partition key named shortcode (data type String)
  • On-Demand capacity mode
URLs

3. Create an IAM Role With DynamoSB-Specific Permissions

export IAM_ROLE_NAME=apprunner-dynamodb-role
aws iam create-role --role-name $IAM_ROLE_NAME --assume-role-policy-document file://apprunner-trust-policy.json

Before creating the policy, update the dynamodb-access-policy.json file to reflect the DynamoDB table ARN name.

aws iam put-role-policy --role-name $IAM_ROLE_NAME --policy-name dynamodb-crud-policy --policy-document file://dynamodb-access-policy.json

Deploy the Application to AWS App Runner

If you have an existing AWS App Runner GitHub connection and want to use that, skip to the Repository selection step.

1. Create an AWS App Runner GitHub Connection

Open the App Runner console and choose Create service.

Create AWS App Runner Service
Create AWS App Runner Service

On the Source and deployment page, in the Source section, for Repository type, choose Source code repository. Under Connect to GitHub, choose Add new, and then, if prompted, provide your GitHub credentials.

Source and deployment: Add GitHub connection
Add GitHub connection

In the Install AWS Connector for GitHub dialog box, if prompted, choose your GitHub account name. If prompted to authorize the AWS Connector for GitHub, choose Authorize AWS Connections. Choose Install.

Your account name appears as the selected GitHub account/organization. You can now choose a repository in your account.

2. Repository Selection

For Repository, choose the repository you created: apprunner-go-runtime-app. For Branch, choose the default branch name of your repository (for example, main).

Configure your deployment: In the Deployment settings section, choose Automatic, and then choose Next.

Choose GitHub repo
Choose GitHub repo

3. Configure Application Build

On the Configure build page, for the Configuration file, choose Configure all settings here.

Provide the following build settings:

  • Runtime: Choose Go 1
  • Build command: Enter go build main.go
  • Start command: Enter ./main
  • Port: Enter 8080

Choose Next.

Configure runtime info

Configure runtime info

4. Configure Your Service

Under Environment variables, add an environment variable. For Key, enter TABLE_NAME, and for Value, enter the name of the DynamoDB table (urls) that you created before.

Add environment variables
Add environment variables

Under Security > Permissions, choose the IAM role that you had created earlier (apprunner-dynamodb-role).

Add IAM role for App Runner
Add IAM role for App Runner

Choose Next.

On the Review and create page, verify all the details you’ve entered, and then choose Create and deploy. If the service is successfully created, the console shows the service dashboard, with a Service overview of the application.

Verify URL Shortener Functionality

The application exposes two endpoints:

  1. To create a short link for a URL
  2. Access the original URL via the short link

First, export the App Runner service endpoint as an environment variable:

export APP_URL=<enter App Runner service URL>
# example
export APP_URL=https://jt6jjprtyi.us-east-1.awsapprunner.com

1. Invoke It With a URL That You Want to Access via a Short Link

curl -i -X POST -d 'https://abhirockzz.github.io/' $APP_URL

# output
HTTP/1.1 200 OK
Date: Thu, 21 Jul 2022 11:03:40 GMT
Content-Length: 25
Content-Type: text/plain; charset=utf-8

{"ShortCode":"ae1e31a6"}

You should get a JSON response with a short code and see an item in the DynamoDB table as well.

You can continue to test the application with other URLs that you want to shorten!

2. Access the URL Associated With the Short Code

Enter the following in your browser http://<enter APP_URL>/<shortcode>

For example, when you enter https://jt6jjprtyi.us-east-1.awsapprunner.com/ae1e31a6, you will be redirected to the original URL.

You can also use curl. Here is an example:

export APP_URL=https://jt6jjprtyi.us-east-1.awsapprunner.com

curl -i $APP_URL/ae1e31a6

# output
HTTP/1.1 302 Found
Location: https://abhirockzz.github.io/
Date: Thu, 21 Jul 2022 11:07:58 GMT
Content-Length: 0