Generated code

Generated Protobuf-ES files are intentionally plain TypeScript: message types, schema exports, typed fields, discriminated oneofs, arrays, and objects. Running buf generate or protoc with protoc-gen-es produces one _pb file per .proto file. Treat generated files as build artifacts: regenerate them instead of editing them by hand.

Files

A .proto file named foo/bar.proto generates one of these files, depending on the selected target:

• foo/bar_pb.ts for target=ts
• foo/bar_pb.js for target=js
• foo/bar_pb.d.ts for target=dts

Each file starts with a generated-file preamble:

// @generated by protoc-gen-es v2.12.0 with parameter "target=ts"
// @generated from file example.proto (package example, syntax proto3)
/* eslint-disable */

Generated imports are relative and follow the plugin options you configured. If your Protobuf file imports another file, the generated code imports the matching _pb output.

File schema

Every generated file exports a file descriptor:

/**
 * Describes the file example.proto.
 */
export const file_example: GenFile = fileDesc(/* ... */);

Use this descriptor with registries and reflection.

Messages

Each Protobuf message becomes a TypeScript type plus a schema export.

message User {
  string first_name = 1;
  string last_name = 2;
  bool active = 3;
  User manager = 4;
  repeated string locations = 5;
  map<string, string> projects = 6;
}

export type User = Message<"example.User"> & {
  firstName: string;
  lastName: string;
  active: boolean;
  manager?: User | undefined;
  locations: string[];
  projects: { [key: string]: string };
};

export const UserSchema: GenMessage<User> = messageDesc(file_example, 0);

Pass the schema to runtime helpers such as create(), fromBinary(), toBinary(), fromJson(), and toJson().

import { create, toBinary } from "@bufbuild/protobuf";
import { type User, UserSchema } from "./gen/example_pb";

const user: User = create(UserSchema, { firstName: "Alice" });
const bytes = toBinary(UserSchema, user);

Enums

Each Protobuf enum becomes a TypeScript enum plus a schema export.

enum PhoneType {
  PHONE_TYPE_UNSPECIFIED = 0;
  PHONE_TYPE_MOBILE = 1;
  PHONE_TYPE_LAND_LINE = 2;
}

export enum PhoneType {
  UNSPECIFIED = 0,
  MOBILE = 1,
  LAND_LINE = 2,
}

export const PhoneTypeSchema: GenEnum<PhoneType> = enumDesc(file_example, 0);

If every enum value shares a prefix that matches the enum name, Protobuf-ES drops that prefix in generated code.

Extensions and services

Extensions become typed extension descriptors:

export const age: GenExtension<User, number> = extDesc(/* ... */);

Services generate schemas only. Protobuf-ES does not include an RPC transport; libraries such as connect-es use these service schemas.

export const UserService: GenService<{
  createUser: {
    methodKind: "unary";
    input: typeof CreateUserRequestSchema;
    output: typeof CreateUserResponseSchema;
  };
}>;

Reference pages

• Field types: Scalar, message, enum, repeated, map, and well-known type field shapes.
• Features: Oneofs, required fields, optional fields, extensions, services, reserved names, nested types, comments, and packages.