Compile with protoc

Though we recommend using Buf to compile your Protobuf files, you can use Protovalidate with protoc. However, without the Buf CLI, you won’t be able to use linting to validate your rules.

This page describes how to add Protovalidate as a dependency and then compile Protovalidate-enabled files with protoc.

Download validate.proto

Protovalidate’s source .proto file is available in GitHub. Follow the steps below to use it with protoc. If you already know how to vendor and include Protobuf dependencies, you’ll notice that this is no different from any other dependency.

First, download validate.proto to the vendor directory:

Download validate.proto as a vendored file

    $ curl --create-dirs \
        -O \
        --output-dir ./vendor/github.com/bufbuild/protovalidate/buf/validate \
        https://raw.githubusercontent.com/bufbuild/protovalidate/refs/heads/main/proto/protovalidate/buf/validate/validate.proto

Import validate.proto

Now that Protovalidate is on the filesystem, you can import it within Protobuf files:

Import buf/validate/validate.proto

syntax = "proto3";

package bufbuild.weather.v1;

import "buf/validate/validate.proto";

Update Makefile (optional)

If you use a Makefile to compile with protoc, update it to include Protovalidate:

Updating Makefile to include Protovalidate

.PHONY: protoc
protoc:
   protoc proto/example/v1/building_example.proto \
   -I. -I./vendor/github.com/bufbuild/protovalidate/ \
   --cpp_out=:./gen

Compile .proto files

With validate.proto in the vendor directory and imported within .proto files, you can now compile with protoc’s -I flag:

Including Protovalidate protoc

$ protoc proto/example/v1/building_example.proto \
    -I. -I./vendor/github.com/bufbuild/protovalidate/ \
    --cpp_out=:./gen
$ echo $?
0