gRPC Proto Analyzer: Inspect .proto Files Online
A proto analyzer parses a Protocol Buffers (.proto) file and shows everything the contract defines: gRPC services, each RPC method with its request and response types and streaming mode, plus every message, field, and enum. Paste or upload a .proto file and the structure is extracted instantly in your browser, the same way this site's WSDL analyzer dissects SOAP contracts, with ready-to-use Python and Node.js client snippets for every method.
How it works
- 1
Paste your .proto file contents or upload the file.
- 2
Click Analyze: services, RPC methods (with streaming modes), messages, and enums are listed.
- 3
Expand any RPC method to copy a Python (grpcio) or Node.js (@grpc/grpc-js) client snippet.
Frequently asked questions
What is a .proto file?
A .proto file is the interface definition for Protocol Buffers and gRPC: it declares message types (structured data with numbered fields) and services (collections of RPC methods with request and response messages). It plays the same role for gRPC that a WSDL file plays for SOAP.
Can I call a gRPC service from the browser?
Not directly. gRPC runs on HTTP/2 with binary framing and trailers that browsers can't produce; calling gRPC from a web page requires a gRPC-Web proxy such as Envoy in front of the server. This tool focuses on analyzing the contract and generating native client code you can run locally.
What do stream keywords mean in an RPC definition?
gRPC supports four call types: unary (plain request/response), server streaming (stream on the response), client streaming (stream on the request), and bidirectional streaming (stream on both). The analyzer labels each method with its call type.
Is my .proto file uploaded to a server?
No. Parsing happens entirely in your browser with JavaScript; the file never leaves your machine.
Does it support proto2 and proto3?
Yes. The parser reads the syntax declaration and handles both proto2 (required/optional/repeated labels) and proto3 (implicit singular fields, optional keyword, maps, oneof blocks).
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