Granc vs gRPC Swagger

Granc is a free, open-source Linux command-line tool written in Rust for dynamic gRPC calls. It sends JSON payloads without requiring service Protobuf files to be compiled into the client, translating JSON to Protobuf and back at runtime. Using a descriptor, it detects unary, server-streaming, client-streaming, and bidirectional RPCs. Schemas can come from server reflection or a local binary FileDescriptorSet file. Commands list services and describe services, messages, and enums. Granc also creates static Markdown documentation cross-linked between services and types. Requests may include custom headers such as authorization or tracing metadata, and JSON is validated before transmission. The core logic is available as a separate library crate for integration tests, proxies, and automation tools. Installation is documented with cargo install --locked granc. The project has moved to Codeberg, while its GitHub repository was archived on March 9, 2026. It is offered under Apache License 2.0 or MIT. TLS support with configurable roots and client identity is on the roadmap.

gRPC Swagger is a free, open-source debugging tool for discovering and calling gRPC methods through Swagger UI. It uses server reflection to scan a registered endpoint, identified by host and port, and then displays available services, method definitions, and parameters. Users can invoke methods with Swagger UI’s “Try it out” control, supplying request data and headers as JSON; the headers are passed to the gRPC server as metadata. Reflection must be enabled on the gRPC service, but the setup instructions say proto files and related implementations do not need modification. The project runs from a released JAR or from source and defaults to port 8080. Configuration can show registered services and expire inactive registrations after a chosen number of seconds. Documented endpoints cover registration, service listing, method calls, and Swagger documentation. It is self-hosted, available for API and web use, and licensed under MIT.