protots

Basic protobuf parser that is built to produce typescript type definitions according to the message types defined in protobuf files. Preferably we want to produce type schemas using zod.

CAUTION: the current state is still to be considered alpha. Use at your own risk.

Development

Running

You can use the usual rust toolchain using cargo:

$ cargo run -- ./some/file.proto

Building

A release build ran be built via:

$ cargo build --release

Implementation notes

As of now, the implementation is loosely based on the official protobuf language spec and the text format spec. However that spec is not accurate based on my experiments. The current protoc compiler(s) allow way more than is described in the specs above.

Therefore I am basically just running tests on a bunch of protobuf files that I found both on my machine and in the wild.

Bottom line, don't be surprised in case you have a proto file that is accepted by the protoc but will not parse completely by protots.

Example

Input

syntax = "proto3";

message Test {
  optional int32 version = 1;
  repeated string names = 2;

  oneof option {
    string foo = 3;
    int64 bar = 4;
  }
}

Output

import { z } from "zod";

export const TestSchema = z.object({
  version: z.optional(z.number()),
  names: z.array(z.string()),
  option: z.union([z.object({ foo: z.string() }), z.object({ bar: z.coerce.bigint() })]),
});

export type Test = z.infer<typeof TestSchema>;

TODO

process all protobuf files in a directory tree at once
thoroughly check protobuf specs and make sure that we support at least everything that is mentioned in there
properly implement and extract field options (see doc)
improve error handling/output
extend unit tests

kongo2002/protots