Deploying Go Applications to AWS App Runner
Tags: aws, containers, devops, docker
Published: 2023-03-10 15:20:54

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:

To create a short link for a URL
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