ProtoValidator

Based on: https://github.com/elixir-protobuf/protoc-gen-validate

Elixir implementation of https://github.com/envoyproxy/protoc-gen-validate

Installation

def deps do
  [
    {:proto_validator, "~> 0.1.0"}
  ]
end

Usage

Developers import the ProtoValidator and annotate the messages and fields in their proto files with constraint rules:

package examplepb

message User {
  uint64 id    = 1 [(validate.rules) = {
    uint64: {gt: 0, lt: 90},
    message: {required: true}
  }];

  string email = 2 [(validate.rules).message.required = true];

  GENDER gender = 3;

  message Phone {
    string phone_number = 1 [(validate.rules) = {
      uint64: {gt: 1000, lt: 2000},
      message: {required: true}
    }];
  }

  repeated Phone phones = 4 [(validate.rules).repeated.min_items = 1];

  repeated uint64 following_ids = 5 [(validate.rules).repeated = {
    min_items: 0,
    unique: true,
    items: {uint64: {gt: 0, lt: 90}}
  }];
}

Then ProtoValidator will generate the validator modules for messages that have constraint rules automatically like:

defmodule ProtoValidator.Gen.Examplepb.User do
  @moduledoc false
  use ProtoValidator, entity: Examplepb.User

  validate(:id, required: true, uint64: [gt: 0, lt: 90])
  validate(:email, required: true)
  validate(:phones, repeated: [min_items: 1])

  validate(:following_ids,
    repeated: [items: [uint64: [gt: 0, lt: 90]], min_items: 0, unique: true]
  )
end

defmodule ProtoValidator.Gen.Examplepb.User.Phone do
  @moduledoc false
  use ProtoValidator, entity: Examplepb.User.Phone

  validate(:phone_number, required: true, uint64: [gt: 1000, lt: 2000])
end

Then both &ProtoValidator.validate/1 and &ProtoValidator.Gen.Examplepb.User/1 can be used to do the validation.

user = Examplepb.User.new()
{:error, _} = ProtoValidator.validate(user)
users = %{user | id: 1}
{:error, _} = ProtoValidator.validate(user)
users = %{user | email: "user@example.com"}
:ok = ProtoValidator.validate(user)
:ok = ProtoValidator.Gen.Examplepb.User.validate(user)

TODO

• Numerics
• Bools
• Strings
• Bytes
• Enums
• Messages
• Repeated
• Maps
• Well-Known Types

How it works

Refer: https://github.com/envoyproxy/protoc-gen-validate

1. Google's Protobuf messages(like google.protobuf.MessageOptions) are extended with validating rules(validate.proto)
2. Your protobuf messages can use validate.proto to define validation options
3. This plugin generate validating code when called by protoc. The code can be called to validate messages
4. Then you can validate your structs