Deploying Spring Boot Applications with AWS

To kick things off, let's create a simple Spring Boot application using the Spring Initializr. Head over to start.spring.io and configure your project with the necessary dependencies. For this tutorial, we'll keep it minimal and select only the Spring Web dependency.

Once you've generated your project, unzip it and import it into your favorite IDE. You'll find a pom.xml file containing your project's dependencies, including Spring Boot itself.

Now, let's create a simple REST controller to get things rolling. Create a new Java class under the com.example.demo package:

package com.example.demo;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class HelloController {

    @GetMapping("/")
    public String hello() {
        return "Hello, AWS!";
    }
}        

This controller defines a single endpoint / that returns a simple greeting.

Deploying to AWS

1. Setting Up AWS Account and IAM Role

Before we dive into deployment, make sure you have an AWS account set up. Once you're logged in, head over to the IAM (Identity and Access Management) dashboard and create a new IAM role with sufficient permissions for your application. For simplicity, you can attach the AmazonEC2FullAccess and AmazonVPCFullAccess policies to your role.

2. Building Your Application

Next, let's build our Spring Boot application. Open a terminal window and navigate to your project's root directory. Run the following Maven command to build a JAR file:

mvn clean package        

This command compiles your code, runs tests, and packages everything into a JAR file located in the target directory.

3. Creating an EC2 Instance

Now, let's launch an EC2 instance to host our application. Go to the EC2 dashboard and launch a new instance. Choose an Amazon Linux AMI, select an instance type that suits your needs, and follow the prompts to configure your instance.

4. Installing Java and Deploying the Application

Once your instance is up and running, SSH into it and install Java using the following commands:

sudo yum update -y
sudo yum install java-1.8.0-openjdk-devel -y        

Now, transfer your JAR file to the EC2 instance using SCP or any preferred method, and then execute the following command to run your Spring Boot application:

java -jar your-application.jar        

Replace your-application.jar with the name of your JAR file.

5. Configuring Security Groups

To allow inbound traffic to your EC2 instance, configure the security group associated with your instance to allow inbound traffic on port 8080 (or the port your application is running on) from anywhere (0.0.0.0/0).

6. Accessing Your Application

Finally, navigate to your EC2 instance's public IP address or domain name followed by the port your application is running on (typically port 8080) in your web browser. You should see your Spring Boot application up and running, ready to greet you with a friendly "Hello, AWS!" message.

Conclusion

In this tutorial, we've walked through the process of deploying a Spring Boot application on AWS step by step. From setting up our project using the Spring Initializr to launching an EC2 instance and deploying our application, we've covered all the essential aspects of deploying Spring Boot applications on AWS. Armed with this knowledge, you're ready to take your Spring Boot applications to the cloud with confidence.

Now, go forth and deploy!