MSG - Microservice Generator

Code Quality & Metrics

Click badges for detailed analysis and metrics on SonarCloud

From SQL to Service - Eliminating microservices boilerplate, one API at a time 🚀

MSG transforms a single SQL statement into a complete, production-ready Spring Boot microservice with REST APIs, DTOs, DAOs, and configuration in seconds.

🎯 What is MSG?

Modern microservices development involves repetitive boilerplate code creation. MSG eliminates this by generating complete Spring Boot microservices directly from SQL statements using a metadata-driven approach.

Core Capabilities

• SELECT → GET APIs with query parameters
• INSERT → POST APIs with validated request bodies
• UPDATE → PUT APIs with path variables and request bodies
• DELETE → DELETE APIs with query parameters
• Complete Projects → Maven structure, dependencies, and configuration

Key Differentiators

• Metadata-driven: Uses database metadata, not SQL parsing
• Type-safe: Generates strongly-typed DTOs with validation
• Production-ready: Includes error handling and proper HTTP semantics
• Enterprise standards: Follows Spring Boot and clean code conventions

🚀 Quick Start

Prerequisites

• Java 21 or later
• Maven 3.8+
• SQL Server database
• Docker (recommended for database setup)

1. Database Setup (One Command)

# Linux/Mac
./setup-db.sh

# Windows  
setup-db.bat

# Manual
docker-compose up -d --build

This sets up SQL Server with sample Sakila database (599 customers, 1000 films, 16k+ rentals).

2. Generate Your First Microservice

# Clone and compile
git clone <repository-url>
cd MSG
mvn clean compile

# Generate SELECT API
mvn exec:java -Dexec.mainClass="com.jfeatures.msg.codegen.MicroServiceGenerator" \
  -Dexec.args="--name Customer --destination ./output --sql-file sample_parameterized_sql.sql"

# Test the generated service
cd ./output
mvn spring-boot:run

3. Test Your API

# Test GET endpoint
curl "http://localhost:8080/api/customer?active=Y&customerId=123"

🔧 Core Commands

Generate All CRUD Operations

# SELECT API (GET endpoints)
mvn exec:java -Dexec.mainClass="com.jfeatures.msg.codegen.MicroServiceGenerator" \
  -Dexec.args="--name Customer --destination ./output --sql-file sample_parameterized_sql.sql"

# INSERT API (POST endpoints)  
mvn exec:java -Dexec.mainClass="com.jfeatures.msg.codegen.MicroServiceGenerator" \
  -Dexec.args="--name Customer --destination ./output --sql-file sample_insert_parameterized.sql"

# UPDATE API (PUT endpoints)
mvn exec:java -Dexec.mainClass="com.jfeatures.msg.codegen.MicroServiceGenerator" \
  -Dexec.args="--name Customer --destination ./output --sql-file sample_update_parameterized.sql"

# DELETE API (DELETE endpoints)
mvn exec:java -Dexec.mainClass="com.jfeatures.msg.codegen.MicroServiceGenerator" \
  -Dexec.args="--name Customer --destination ./output --sql-file sample_delete_parameterized.sql"

📁 SQL File Requirements

Place SQL files in src/main/resources/ with parameterized queries:

-- sample_parameterized_sql.sql (SELECT)
SELECT c.customer_id, c.first_name, c.last_name 
FROM customer c 
WHERE c.active = ? AND c.created_date >= ?

-- sample_insert_parameterized.sql (INSERT)  
INSERT INTO customer (first_name, last_name, email) 
VALUES (?, ?, ?)

-- sample_update_parameterized.sql (UPDATE)
UPDATE customer SET first_name = ?, email = ? 
WHERE customer_id = ?

-- sample_delete_parameterized.sql (DELETE)
DELETE FROM customer WHERE customer_id = ? AND active = ?

🏗️ Generated Code Structure

generated-microservice/
├── pom.xml
├── src/main/java/com/jfeatures/msg/{domain}/
│   ├── Application.java
│   ├── controller/{Domain}Controller.java
│   ├── dao/{Domain}DAO.java  
│   ├── dto/{Domain}DTO.java
│   └── config/DatabaseConfig.java
└── src/main/resources/application.properties

📖 Documentation

• User Guide - Complete usage instructions and examples
• Developer Guide - Architecture and contribution guide
• Security Guide - Security best practices and known issues
• Troubleshooting - Common issues and solutions

🎉 Success Stories

MSG transforms microservices development by:

• 90% Less Boilerplate: Eliminates repetitive CRUD code writing
• Type-Safe APIs: Generates strongly-typed DTOs and controllers
• Production Ready: Includes validation, error handling, and proper HTTP semantics
• Rapid Prototyping: From SQL to running service in minutes

👥 Contributing

We welcome contributions! Please see our Developer Guide for:

• Development setup and workflow
• Architecture overview and design principles
• Adding new features and SQL statement types
• Code standards and pull request process

📝 License

This project is licensed under the Apache License 2.0. See the LICENSE file for details.

---

Created with clean code principles and architectural excellence in mind.

MSG - Building the future of microservices generation 🚀