Spring Boot GRPC Project Example

Multi-Module Spring Boot and gRPC Example Project

Project Overview

This project serves as a practical implementation of gRPC within a Spring Boot multi-module architecture, enabling efficient, high-performance service-to-service communication. It provides a structured approach to building scalable microservices, leveraging gRPC for low-latency, high-throughput interactions while maintaining compatibility with traditional REST clients.

Architecture & Communication Patterns

• Client Interaction:

  • A RESTful API, exposed via HTTP 1.1, is served through a Tomcat web server.
  • The client communicates via standard REST endpoints, interacting with the underlying gRPC-based services.

• Inter-Module Communication:

  • Modules interact with each other via gRPC, supporting both:
    • Synchronous communication for real-time request-response interactions.
    • Asynchronous communication using gRPC streaming for event-driven processing.

Key Features & Enhancements

• Spring Boot Integration:

  • Seamlessly integrates gRPC server and client with the Spring Boot application context.
  • Uses Spring Boot’s dependency injection (DI) and configuration management for gRPC services.

• Governance & Observability:

  • Logging: Comprehensive gRPC request/response logging for debugging and monitoring.
  • Header Enrichment: Metadata propagation to enhance service traceability.
  • Security: Implementing authentication/authorization strategies such as JWT, mTLS, and API keys.

• Scalability & Performance Optimizations:

  • Load balancing: Configuring client-side or service-side load balancing for high availability.
  • Connection pooling: Efficient management of gRPC channels to optimize resource usage.
  • Resilience mechanisms: Implementing timeouts, retries, and circuit breakers to handle failures gracefully.

Benefits & Use Cases

✅ Low-latency, high-performance communication between microservices.
✅ Efficient resource utilization with persistent connections.
✅ Hybrid integration: Supports both gRPC-based service-to-service calls and RESTful clients.
✅ Enhanced security and governance for production-grade deployments.
✅ Scalable and modular design for large-scale microservices architectures.

🚀 This project provides a solid foundation for building microservices using Spring Boot and gRPC, combining modern communication patterns with enterprise-grade best practices.

Flows

Testing

MacOS

brew install grpcurl

GRPC URL

grpcurl -v -d '{"smsHeader": "1234", "msgTxt":"Hello pims" , "receiverMsisdn" : "905557502861", "txKey" : "TX-1" }' \n
-plaintext localhost:9090 com.inomera.pims.sal.MessagingService/sendCustomerAcknowledgeMsg

REST API

Async

curl --location 'http://localhost:8080/ws/rest/external/v10/messages/send/async' 
--header 'Content-Type: application/json' \
--data '{
    "smsHeader": "1234",
    "msgTxt": "Hello pims",
    "receiverMsisdn": "905557502861",
    "txKey": "TX-1"
}'

Sync

curl --location 'http://localhost:8080/ws/rest/external/v10/messages/send/process' 
--header 'Content-Type: application/json' \
--data '{
    "smsHeader": "1234",
    "msgTxt": "Hello pims",
    "receiverMsisdn": "905557502861",
    "txKey": "TX-1"
}'

Load Test with Siege

MacOS

brew install siege

you can find siege files under files directory.

concurrent 5 users, no delay, 30 seconds

#!/bin/bash

siege -d0 -c5 -t30S \
-H 'Content-Type: application/json' \
'http://localhost:8080/ws/rest/external/v10/messages/send/process POST { "header": "7070","msisdn": "905077505015","text": "Hoş geldin process GRPC"}' \
-H 'Accept:application/json' 

Output

Lifting the server siege...
Transactions:		       10211 hits
Availability:		      100.00 %
Elapsed time:		       31.03 secs
Data transferred:	        0.47 MB
Response time:		        0.00 secs
Transaction rate:	      329.07 trans/sec
Throughput:		        0.02 MB/sec
Concurrency:		        0.63
Successful transactions:       10211
Failed transactions:	           0
Longest transaction:	        6.72
Shortest transaction:	        0.00

Tech Stack

• Spring Boot 3.4.2
• Spring GRPC Boot 0.4.0-SHAPSHOT
• GRPC 1.7.0
• Apache Tomcat 10+
• Protobuf