Spring Boot Hello World with Docker

License

This project is licensed under MIT license. See the LICENSE file for more informations.

About the Project

This is a simple Spring Boot app to send hello world message to a user.

The reason for this simple project was so that I could pratice and further implement my knowledge in Docker. Therfore, I was able to better understand how a Java Application is containerized using the SpringBoot framework, by creating an Image defined in Dockerfile.

Furthermore, this project also contributed to my development by addresing the good practices of implementing Unit Tests, so I understood that the use of MockMvc allowos testing the control layer of a Spring Application without the need to upload a real server, making tests faster and more efficient.

How to Run Application

Start the application using any of the commands mentioned below?

Note: The commands need to run inside the root folder of this project i.e inside the java-docker-helloWorld 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/hello-world-0.0.1-SNAPSHOT.jar.jar

• Using Docker

  • Image construction:
    docker build -t image_name .
  • Climb Container:
    docker run -d --name container_name -p 9090:9090 image_name

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 '/api/hello' endpoint using any of the two methods

• Browser or REST client
  http://localhost:9090/api/hello

• cURL
  curl --request GET 'http://localhost:9090/api/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 java-docker-helloWorld folder

• To run all the test cases
  mvn test

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