Spring Boot Project Creator

Overview

Generates a fully configured Spring Boot project from scratch using the Spring Initializr API. The skill walks the user through selecting project parameters, choosing an architecture style (DDD or Layered), configuring data stores, and setting up Docker Compose for local development. The result is a build-ready project with standardized structure, dependency management, and configuration.

When to Use

• Bootstrap a new Spring Boot 3.x or 4.x project with a standard structure.
• Initialize a backend microservice with JPA, SpringDoc OpenAPI, and Docker Compose.
• Scaffold a project following either DDD (Domain-Driven Design) or Layered (Controller/Service/Repository/Model) architecture.
• Set up local development infrastructure with PostgreSQL, Redis, and/or MongoDB via Docker Compose.
• Trigger phrases: "create spring boot project", "new spring boot app", "bootstrap java project", "scaffold spring boot microservice", "initialize spring boot backend", "generate spring boot project".

Prerequisites

Before starting, ensure the following tools are installed:

• Java Development Kit (JDK): Version 17+ (Java 21 recommended for Spring Boot 3.x/4.x)
• Apache Maven: Build tool (Spring Initializr generates Maven projects by default)
• Docker and Docker Compose: For running local infrastructure services
• curl and unzip: For downloading and extracting the project from Spring Initializr

Instructions

Follow these steps to create a new Spring Boot project.

1. Gather Project Configuration

Ask the user for the following project parameters using AskUserQuestion. Provide sensible defaults:

2. Generate Project with Spring Initializr

Use curl to download the project scaffold from start.spring.io.

Base dependencies (always included):

• web — Spring Web MVC
• validation — Jakarta Bean Validation
• data-jpa — Spring Data JPA
• testcontainers — Testcontainers support

Conditional dependencies (based on Docker Services selection):

• PostgreSQL selected → add postgresql
• Redis selected → add data-redis
• MongoDB selected → add data-mongodb

# Example for Spring Boot 3.4.5 with PostgreSQL only
curl -s https://start.spring.io/starter.zip \
  -d type=maven-project \
  -d language=java \
  -d bootVersion=3.4.5 \
  -d groupId=com.example \
  -d artifactId=demo \
  -d packageName=com.example \
  -d javaVersion=21 \
  -d packaging=jar \
  -d dependencies=web,data-jpa,postgresql,validation,testcontainers \
  -o starter.zip

unzip -o starter.zip -d ./demo
rm starter.zip
cd demo

3. Add Additional Dependencies

Edit pom.xml to add SpringDoc OpenAPI and ArchUnit for architectural testing.

<!-- SpringDoc OpenAPI -->
<dependency>
    <groupId>org.springdoc</groupId>
    <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
    <version>2.8.15</version>
</dependency>

<!-- ArchUnit for architecture tests -->
<dependency>
    <groupId>com.tngtech.archunit</groupId>
    <artifactId>archunit-junit5</artifactId>
    <version>1.4.1</version>
    <scope>test</scope>
</dependency>

4. Create Architecture Structure

Based on the user's choice, create the package structure under src/main/java/<packagePath>/.

Option A: Layered Architecture

src/main/java/com/example/
├── controller/        # REST controllers (@RestController)
├── service/           # Business logic (@Service)
├── repository/        # Data access (@Repository, Spring Data interfaces)
├── model/             # JPA entities (@Entity)
│   └── dto/           # Request/Response DTOs (Java records)
├── config/            # Configuration classes (@Configuration)
└── exception/         # Custom exceptions and @ControllerAdvice

Create placeholder classes for each layer:

• config/OpenApiConfig.java — SpringDoc OpenAPI configuration bean
• exception/GlobalExceptionHandler.java — @RestControllerAdvice with standard error handling
• model/dto/ErrorResponse.java — Standard error response record

Option B: DDD (Domain-Driven Design) Architecture

src/main/java/com/example/
├── domain/                 # Core domain (framework-free)
│   ├── model/              # Entities, Value Objects, Aggregates
│   ├── repository/         # Repository interfaces (ports)
│   └── exception/          # Domain exceptions
├── application/            # Use cases / Application services
│   ├── service/            # @Service orchestration
│   └── dto/                # Input/Output DTOs (records)
├── infrastructure/         # External adapters
│   ├── persistence/        # JPA entities, Spring Data repos
│   └── config/             # Spring @Configuration
└── presentation/           # REST API layer
    ├── controller/         # @RestController
    └── exception/          # @RestControllerAdvice

Create placeholder classes for each layer:

• infrastructure/config/OpenApiConfig.java — SpringDoc OpenAPI configuration bean
• presentation/exception/GlobalExceptionHandler.java — @RestControllerAdvice with standard error handling
• application/dto/ErrorResponse.java — Standard error response record

5. Configure Application Properties

Create src/main/resources/application.properties with the selected services.

Always include:

# Application
spring.application.name=${artifactId}

# SpringDoc OpenAPI
springdoc.swagger-ui.doc-expansion=none
springdoc.swagger-ui.operations-sorter=alpha
springdoc.swagger-ui.tags-sorter=alpha

If PostgreSQL is selected:

# PostgreSQL / JPA
spring.datasource.driver-class-name=org.postgresql.Driver
spring.datasource.url=jdbc:postgresql://localhost:5432/${POSTGRES_DB:postgres}
spring.datasource.username=${POSTGRES_USER:postgres}
spring.datasource.password=${POSTGRES_PASSWORD:changeme}
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=true

If Redis is selected:

# Redis
spring.data.redis.host=localhost
spring.data.redis.port=6379
spring.data.redis.password=${REDIS_PASSWORD:changeme}

If MongoDB is selected:

# MongoDB
spring.data.mongodb.host=localhost
spring.data.mongodb.port=27017
spring.data.mongodb.authentication-database=admin
spring.data.mongodb.username=${MONGO_USER:root}
spring.data.mongodb.password=${MONGO_PASSWORD:changeme}
spring.data.mongodb.database=${MONGO_DB:test}

6. Set Up Docker Compose

Create docker-compose.yaml at the project root with only the services the user selected.

services:
  # Include if PostgreSQL selected
  postgresql:
    image: postgres:17
    ports:
      - "5432:5432"
    environment:
      POSTGRES_USER: ${POSTGRES_USER:-postgres}
      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-changeme}
      POSTGRES_DB: ${POSTGRES_DB:-postgres}
    volumes:
      - ./postgres_data:/var/lib/postgresql/data

  # Include if Redis selected
  redis:
    image: redis:7
    ports:
      - "6379:6379"
    command: redis-server --requirepass ${REDIS_PASSWORD:-changeme}
    volumes:
      - ./redis_data:/data

  # Include if MongoDB selected
  mongodb:
    image: mongo:8
    ports:
      - "27017:27017"
    environment:
      MONGO_INITDB_ROOT_USERNAME: ${MONGO_USER:-root}
      MONGO_INITDB_ROOT_PASSWORD: ${MONGO_PASSWORD:-changeme}
    volumes:
      - ./mongo_data:/data/db