Exploring Spring Boot Shell: A Step-by-Step Guide with Examples

Introduction:

Spring Boot Shell is a powerful and extensible command-line interface (CLI) tool that enhances the development experience for Spring Boot applications. It provides a convenient way to interact with your Spring Boot projects, allowing you to execute commands, explore configurations, and manage application components efficiently. In this guide, we will walk through the basics of Spring Boot Shell with hands-on examples.

Getting Started

1. Add Spring Boot Shell Dependency:

Start by adding the Spring Boot Shell dependency to your project. In your build.gradle or pom.xml file, include:

   // For Gradle
   implementation 'org.springframework.boot:spring-boot-starter'
   implementation 'org.springframework.boot:spring-boot-starter-shell'

   // For Maven
   <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter</artifactId>
   </dependency>
   <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-shell</artifactId>
   </dependency>

2. Create a Simple Spring Boot Application:

Create a basic Spring Boot application or use an existing one. Ensure it has a main method annotated with @SpringBootApplication.

3. Enable Spring Boot Shell:

In your application class, extend org.springframework.shell.jline.InteractiveShellApplication:

Using Spring Boot Shell

4. Basic Commands:

Spring Boot Shell provides various built-in commands. For instance, you can use help to view available commands and clear to clear the console.

   shell:> help
   shell:> clear

5. Creating Custom Commands:

Define your custom commands by creating @ShellComponent beans. For example:

Now, when you run the shell, your custom command greet will be available:

   shell:> greet

6. Command Parameters:

Add parameters to your commands for more flexibility:

Use the command with parameters:

   shell:> greet John

7. Scripting with Groovy:

Spring Boot Shell supports Groovy scripts. Create a Groovy script, for instance, myscript.groovy:

   println "Executing Groovy Script!"

Run the script in the shell:

   shell:> script --file=myscript.groovy

8. Working with Application Context:

Access Spring application context within your commands:

Execute the command:

   shell:> activeProfiles

Conclusion

Spring Boot Shell enhances the developer’s experience by providing a convenient command-line interface for Spring Boot applications. In this guide, we covered the basic setup, creating custom commands, handling parameters, scripting with Groovy, and accessing the application context. Incorporate Spring Boot Shell into your projects to streamline command-line interactions and improve productivity.