PolyCalc - A gRPC Multi-Language Calculator Service

Overview

PolyCalc is a distributed calculator service implemented using gRPC and Protocol Buffers across three languages. The project features a Java client that communicates with two separate servers—a Go server (handling addition) and a Python server (handling multiplication). This setup demonstrates cross-language interoperability using a common gRPC API.

Technical Stack

• Languages: Java, Go, Python
• Communication: gRPC, Protocol Buffers
• Design Patterns: Stream Observer Pattern

Key Features

• Cross-Language RPC:
  • ➕ Go-based Addition Service (Port 2000)
  • ✖️ Python-based Multiplication Service (Port 3000)
  • 🇯 Java Client Interface with interactive console
• Streaming Architecture:
  • Server-side streaming responses
  • Async result handling
  • Error streaming with SLF4J logging
• Protocol Buffers:
  • Unified calculator.proto definition
  • Auto-generated stubs for all languages
  • Compact binary serialization

Project Structure

gRPC-multi-language(Java-Go-Python)/
├── java-client/               # Java Client Implementation
│   ├── src/main/java/org/ds/
│   │   └── gClient.java       # Client logic
│   ├── src/main/proto/
│   │   └── calculator.proto   # Service contracts
│   └── pom.xml                # Dependency management
│
├── go-server/                 # Go Addition Service
│   ├── main.go                # Server implementation
│   └── calculator.proto       # Protobuf definition
│
└── python-server/             # Python Multiplication Service
    ├── main.py                # Server implementation
    └── calculator.proto       # Protobuf definition

Installation

Prerequisites

• Java 17 or higher (client)
• Go (server)
• Python 3.7 or higher (server)
• Maven (for Java build)
• gRPC tools / protoc (for generating code from .proto files)

Clone the Repository

git clone https://github.com/ahmadabdelbary2001/gRPC-multi-language-Java-Go-Python.git

Build & Run

1. Build the Java Client

   mvn clean install

2. Generate gRPC for Go (Addition Service)

   cd go-server
   protoc --go_out=. --go-grpc_out=. calculator.proto
   go run main.go

3. Generate gRPC for Python (Multiplication Service)

   cd python-server
   python -m grpc_tools.protoc -I. --python_out=. --grpc_python_out=. calculator.proto
   python main.py