Spring Boot Hello World

A simple Spring Boot 2.x app to send hello world message to a user

Dockerizing a Spring Boot Application

This tutorial will guide you through the steps to dockerize a Spring Boot application, including creating a Dockerfile, building the Docker

Step 1: Build the Application

• 1.1 Package the Application
  
• Maven
  mvn -DskipTests=true clean package

Step 2: Build the Docker Image

• 2.1 Build the Image
  docker build -t spring-hello-world-docker .

Step 3: Run the Docker Container

• 3.1 Run the Container
  docker run -p 8080:8080 spring-hello-world-docker

Step 4: Test the Application

• 4.1 Access the Application
  Open your browser and navigate to http://localhost:8080/hello. You should see the following response:

How to Run Application

Start the application using any of the commands mentioned below

Note: First two commands need to run inside the root folder of this project i.e inside the spring-boot-hello-world folder

• Using maven
  mvn spring-boot:run

• From jar file Create a jar file using 'mvn clean install' command and then execute
  java -jar target/spring-boot-2-hello-world-1.0.2-SNAPSHOT.jar

• Directly from IDE
  Right click on HelloWorldApplication.java and click on 'Run' option
Set Bind Port: 8080:8080
  

Note: By default spring boot application starts on port number 8080. If port 8080 is occupied in your system then you can change the port number by uncommenting and updating the server.port property inside the application.properties file that is available inside the src > main > resources folder.

Send an HTTP GET request to '/hello' endpoint using any of the two methods

• Browser or REST client
  http://localhost:8080/hello

• cURL
  curl --request GET 'http://localhost:8080/hello'

How to Run Unit Test Cases

Run the test cases using any of the commands mentioned below

Note: These commands need to run inside the root folder of this project i.e inside the spring-boot-hello-world folder

• To run all the test cases
  mvn test

• To run a particular test class
  mvn -Dtest=HelloWorldControllerTest test
  or
  mvn -Dtest=HelloWorldApplicationTests test