Spring Boot Microservice Project Starter Generator DSL

Introduction

A Domain-Specific Language (DSL) designed to streamline and automate the creation of Spring Boot microservice architectures. This tool empowers developers to rapidly prototype and deploy microservice-based applications by providing a declarative approach to defining service configurations, dependencies, and interactions.

Problem Statement

Setting up a microservice architecture with Spring Boot involves numerous repetitive tasks:

• Creating consistent project structures across multiple services
• Configuring service discovery, API gateway, and config servers
• Managing inter-service dependencies and communication
• Ensuring consistent configuration across all services
• Implementing proper service discovery and registration

This DSL addresses these challenges by providing a simple, declarative way to define entire microservice architectures, reducing setup time and potential configuration errors.

Grammar Definition

Project Structure

The root element containing all microservice components:

• project: Defines the project name (required)
• group: Specifies the project group ID (required)
• version: Sets the project version (required)
• description: Provides project description (optional)

Discovery Service

Eureka server configuration for service discovery:

• discovery: Service name for the Eureka server
• port: Server port number
• defaultZone: Eureka server URL for client registration
• dependencies: Additional dependencies beyond default ones

Config Server

Centralized configuration management:

• config-server: Server name
• port: Server port number
• git-uri: Git repository URL containing configuration files
• git-branch: Target Git branch for configurations
• dependencies: Required dependencies for the config server

Microservices

Individual service definitions with comprehensive configuration options:

• service: Unique service identifier
• dependencies: Service-specific dependencies including:
  • Predefined dependency sets (JPA, LOMBOK, etc.)
  • Custom dependencies
• config: Service configuration sections:
  • server-config: Server-specific settings
    • port: Service port number
    • context-path: Base URL path
  • application-config: Application settings
    • name: Application name
    • profile: Active profile
    • logging: Logging configuration
  • database-config: Database connectivity
    • url: JDBC connection URL
    • username: Database username
    • password: Database password
    • driver: Database driver type
    • ddl: Schema generation strategy
  • actuator-config: Monitoring endpoint configuration

API Gateway

Central entry point for the microservice ecosystem:

• gateway: Gateway service name
• port: Gateway port number
• routes: Service routing configuration
  • path: URL path pattern
  • service: Target service name
• dependencies: Gateway-specific dependencies

Example Usage

project myproject
group com.example.micro
version "1.0.0"
description "My microservices project"
{
    discovery eureka {
        port 8762
        defaultZone "http://localhost:8761/eureka/"
        dependencies { }
    }
    service service1 {
        dependencies {
            CONFIG_CLIENT
            JPA
            LOMBOK
        }
        config {
            application-config {
                name "dddd"
            }
            server-config {
                port 8081
                context-path "/service1"
            }
            database-config {
                url "jdbc:mysql://localhost:3306/dbn"
                username "user"
                password "pass"
                driver MYSQL
                ddl CREATE_UPDATE
            }
        }
    }

    gateway apigateway {
        port 8080
        routes {
            route {
                path "/api/service1/**"
                service service1
            }
        }
        dependencies { }
    }
}

Validation Rules

Port Validation

• Valid port range: 1024-65535
• Port uniqueness across all components
• Required port configuration for all networked services

Service Validation

• Unique service names across the project
• Mandatory server configuration
• Recommended application configuration
• Complete database configuration when present:
  • Valid JDBC URL format validation
  • Required credentials
  • Supported database driver specification

Dependency Validation

• Automatic inclusion of core dependencies:
  • SPRING_WEB
  • EUREKA_CLIENT
• JPA dependency requirement for database configurations
• Recommended CONFIG_CLIENT for all services

Route Validation

• Unique route paths in gateway configuration
• Existence validation for referenced services
• Valid URL pattern formatting

Generated Output

Directory Structure

The DSL generates a complete project structure including:

• Separate modules for each service
• Configuration files
• Service implementations
• Common utility modules

Generated Artifacts

• Service-specific application.yml files
• Docker configuration files
• Service discovery configuration
• API gateway routing setup
• Database configuration files

Limitations

Current version limitations:

• Focuses on project structure and configuration only
• Limited to Spring Boot ecosystem
• No support for custom security configurations

Future Enhancements

Planned features for future releases:

• Custom security configuration support
• Basic service implementation templates
• Custom dependency management