Charlatan

A lightweight Go-based gRPC server featuring user management and product response simulations. Built using modern gRPC practices, it features thread-safe in-memory storage, gRPC reflection for easy testing, and clean, graceful shutdown handling.

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Features

• User Management: Thread-safe user creation and listing.
• Product Endpoint: Simulates dynamic product data handling with fallback defaults.
• Health Check: Native endpoints for standard ping and application status validation.
• gRPC Reflection: Enabled out of the box for quick debugging with tools like grpcurl.
• Graceful Shutdown: Listens for system interrupts (SIGINT, SIGTERM) to cleanly terminate running instances without dropping active connections.

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API Endpoints

The server exposes the UserService containing the following RPCs:

Method	Request	Response	Description
GetRoot	Empty	StringResponse	Returns a static "Goodbye, World!" greeting.
HealthCheck	Empty	StringResponse	Simple endpoint returning an "OK" status.
GetProduct	ProductRequest	ProductResponse	Echoes product requirements with default limit handling.
CreateUser	CreateUserRequest	User	Stores a new user to an in-memory database with validation.
ListUsers	Empty	UserListResponse	Returns all registered users.

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Getting Started

Installation & Running

# Clone the repository and navigate to its root directory
git clone https://github.com/Isvane/charlatan.git
cd charlatan

# Download dependencies
go mod download

# Start the server
go run main.go

Testing with grpcurl

# Check Server Health
grpcurl -plaintext localhost:8000 pb.UserService/HealthCheck

# Create a User
grpcurl -plaintext -d '{"name": "Alice", "email": "alice@example.com"}' localhost:8000 pb.UserService/CreateUser

# List Users
grpcurl -plaintext localhost:8000 pb.UserService/ListUsers