plug

plug is a minimal plugin system for go based on the amazing Hashicorp go-plugin system. It uses the same basic concept of launching the plugin as a subprocess using the os/exec package. It then communicates with the plugin process using IPC and serialized protobufs. Here are a few differences:

• The plugin interface will be generated automatically using a new protobuf code generator called protoc-gen-plug.
• Instead of attaching the stdin/stdout streams to the host process it uses them for communication between the plugin and host.
• It uses a custom protocol for communication between the host and plugin, this is much faster but also has fewer bells and whistles. There are many limitations that will probably not be addressed.

If you want a system that is battle tested and well-supported, please use Hashicorp's go-plugin system. If you need something very simple with good performance characteristics, this system might be for you.

Usage

This package uses the new go protobuf implementation google.golang.org/protobuf,

1. Install protoc-gen-go (from google.golang.org/protobuf) and protoc-gen-plug to your path
2. Create a protobuf with your service definitions (See example/example.proto)
3. Generate both the go and plug code (See example/gen.sh)
4. Implement a generated plugin interface (See example/kv/main.go)
5. Use the plugin with the generated Load{Service} function.

Notes

The plug generator will unwrap the root request and response types from your service rpc definition. If the message types include embedded types, you will be responsible for providing/consuming the protobuf type from the generated interface API.