--grpc_out=minimal_node_version seems to not work

[michael-donat]

Problem description

Using grpc_tools_node_protoc --js_out=import_style=commonjs,binary:. --grpc_out=minimum_node_version=8:. hello.proto produces generated code with new Buffer() instead of Buffer.from

It seems that the options are not passed to the compiler, trying an invalid option doesn't throw an error as expected from here: grpc/grpc@1de3f4a#diff-016162c2cbf07456eef32601d02d20b3R53

Reproduction steps

hello.proto

// Copyright 2016 Google, Inc. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

syntax = "proto3";

package hello;

// The hello service definition.
service Hello {
  // Sends a greeting.
  rpc Say (Request) returns (Response);
}

// The request message containing the user's name.
message Request {
  string name = 1;
}

// The response message containing the greeting.
message Response {
  string message = 1;
}

 -> npm install -g grpc-tools
/usr/local/bin/grpc_tools_node_protoc -> /usr/local/lib/node_modules/grpc-tools/bin/protoc.js
/usr/local/bin/grpc_tools_node_protoc_plugin -> /usr/local/lib/node_modules/grpc-tools/bin/protoc_plugin.js

> grpc-tools@1.6.6 install /usr/local/lib/node_modules/grpc-tools
> node-pre-gyp install

[grpc-tools] Success: "/usr/local/lib/node_modules/grpc-tools/bin/grpc_tools.node" is installed via remote
+ grpc-tools@1.6.6
updated 1 package in 6.666s

grpc_tools_node_protoc --js_out=import_style=commonjs,binary:. --grpc_out=minimum_node_version=8:. hello.proto

The output file contains

function serialize_hello_Response(arg) {
  if (!(arg instanceof hello_pb.Response)) {
    throw new Error('Expected argument of type hello.Response');
  }
  return new Buffer(arg.serializeBinary());
}

which throws DeprecationWarning

Environment

• MacOS HighSierra 10.13.5
• Node v10.5.0
• brew
• package grpc-tools@1.6.6
• grpc_tools_node_protoc --version = libprotoc 3.4.0

Additional info

I've noticed that the NPM package has been last updated 9 months ago while the commit bringing support to minimum_node_version is from 1st of May, I suppose the issue comes from an outdated plugin?

[nicolasnoble]

Yes, you assume correctly - the package doesn't have the new option yet.

[michael-donat]

@nicolasnoble thanks for the quick reply, are there any particular blockers to this or is it the usual plenty of other things on the list?

I would love to submit a PR but don't even know where to start.

the workaround so far has been sed -i '' -e 's/new Buffer(/Buffer.from(/g' file_pb.js ;)

Also, how can I get my hands on latest grpc_node_plugin?

[nicolasnoble]

Well, right about now, the best option is to compile it from source - this is one of the last few things we haven't properly migrated yet, so it's still over at https://github.com/grpc/grpc. We haven't prioritized it yet to be honest.

[murgatroid99]

We have published a new version of grpc-tools that emits code using Buffer.from without using any special options.