IntelliJ IDEA 2019.2 Help

Run and debug a Spring Boot application using Docker Compose

You can use IntelliJ IDEA to run and debug a Spring Boot application running in multiple Docker containers under Docker Compose. This tutorial describes how to run two Docker Compose services inside containers: a simple Spring Boot application and a MySQL database. The application can receive GET requests that add entries to the database. This tutorial also describes how you can set breakpoints and debug your application using a remote debug configuration.

Clone the sample project

The source code of the application is hosted on GitHub.

  1. In the main menu, select VCS | Checkout from Version Control | Git

  2. Specify the URL: https://github.com/IdeaUJetBrains/SpringBootDockerDemoDebug

    Test the connection if necessary and click Clone.

  3. Agree to open the cloned project.

Run the application using Docker Compose

  1. Open the docker-compose-debug.yml file.

  2. Click docker-compose up in the gutter.

    This creates a Docker Compose run configuration, which starts the application in a container as the app service and the database in another container as the db service. If successful, you should see something similar to the following in the deploy log:

    Creating db ... Creating springbootdockerdemodebug2_app_1 ... 'Compose: docker-compose-debug.yml' has been deployed successfully.

    You can access the application at http://localhost:18080. For example, you can try to execute the following GET request, which should add a new entitybus entry to the database and list all available entries: http://127.0.0.1:18080/entitybus/post

    You can connect to the database at jdbc:mysql://0.0.0.0:13306/DOCKERDB. For example, you can use the Database tool window to add the database as a data source and check the entitybus table. Use the following connection settings:

    • Host: 0.0.0.0 or localhost

    • Port: 13306

    • User: root

    • Password: root

    • Database: DOCKERDB

Create a remote debug configuration

  1. Open the docker-compose-debug.yml file.

  2. Click Debug with Remote in the gutter.

  3. Select the module in the Use module classpath list.

  4. Double-click the Docker Compose run configuration in the Before launch list. If it is not in the list, click the Add button and select Launch Docker before debug.

  5. Select the Docker Compose run configuration to launch before starting remote debug and make sure that it is configured to connect to the app service. Also check the Custom Command field: it should contain the -agentlib option and options from the command field in the docker-compose-debug.yml file:

    java -agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=5005 -Djava.security.egd=file:/dev/./urandom -jar /project/target/demo-0.0.1-SNAPSHOT.jar

If the application is already running, do not run the debug configuration. Apply the settings and click Cancel.

Launch the debug configuration

  1. If the application is already running, remove the containers. To do it, right-click the containers under the Docker Compose app and db services and click Delete.

  2. Open the docker-compose-debug.yml file.

  3. Click Debug with Remote in the gutter and start the debug configuration.

Once the application is up and running, the Debug tool window opens.

Set a breakpoint and debug the application

  1. Open the src/main/java/entity/Entitybus.java file and set a breakpoint in the setEid() method.

    Breakpoint in the setEid() method
  2. Execute the following GET request: http://127.0.0.1:18080/entitybus/post

    The application will stop at the breakpoint and you can examine the current variable values and frames in the Debug tool window.

  3. Click the Resume Program button until it executes the request and you get the returned values.

Last modified: 23 August 2019