keva-mock

A high-performance, configuration-driven Mock Server built in Rust.

keva-mock is designed to simulate complex backend systems, third-party services (e.g., Payment Gateways, ERPs), and internal microservices. It focuses on Developer Experience, Performance, and Correctness.

🚀 Key Features

• Multi-Tenant Workspaces: Run multiple isolated mock environments (e.g., /stripe, /transferwise) on a single server instance.
• Dynamic Routing: zero-copy path matching with support for wildcard and parameterized routes.
• Strict Schema Validation: Validate incoming requests (Body, Query, Headers) and outgoing responses against defined schemas (JSON Schema / TOML).
• Scripting Hooks (Rhai): Attach dynamic logic (onRequest, onResponse) using Rhai - a safe, embedded scripting language for Rust.
• Scheduled Jobs: Native Cron support to trigger webhooks or internal actions.
• Chaos Engineering: Built-in support for simulating Latency, Timeouts, and Errors via headers.
• Vertical Slice Architecture: Codebase organized by Functional Capability for maintainability.

📦 Installation

# Clone the repository
git clone https://github.com/kevalabs/keva-mock.git

# Build via Cargo
cargo build --release

# Run
./target/release/keva-mock --server-config server.toml

🛠 Configuration

keva-mock uses a hierarchical configuration system.

1. Global Server Config (server.toml)

Defines the listener and workspace mappings.

[server]
port = 3000
host = "0.0.0.0"

[workspaces]
# Mount workspaces to context roots
"/stripe" = "./mocks/stripe"
"/transferwise" = "./mocks/transferwise"

2. Workspace Config (mocks/stripe/config.toml)

Defines the behavior for a specific domain.

root = "/stripe"

[database]
url = "postgres://user:pass@localhost:5432/stripe_mock"

[[endpoints]]
path = "/v1/payment/initiate"
method = "POST"
    [endpoints.request]
    schema_file = "schemas/initiate_req.toml"

    [endpoints.response]
    source = "file"
    file = "data/success_response.toml"
    # Or use a script for dynamic logic
    # source = "script"
    # script_file = "scripts/initiate_payment.rhai"

🧠 Architecture

keva-mock follows a Vertical Slice Architecture to keep related logic (Routing, Validation, Mocking) co-located.

• Core: Async Request Pipeline built on Axum and Tokio.
• Engine: Rhai scripting engine for dynamic behavior without recompilation.
• Storage: SQLx for DB interaction and Redis for distributed state (e.g., Rate Limiting).

🤝 Contributing

1. Fork the repo.
2. Create a feature branch (git checkout -b feature/amazing-feature).
3. Commit your changes.
4. Open a Pull Request.

📄 License

MIT