streams

Streams: Just give me a stream!

Streams is an interface for using multiplexing transport protocols in Go. The intent is to make creating and receiving streams easy to use from an application. Streams is designed to provide a unified implementation for building applications which require multiplexed streaming and need to easily swap between underlying implementations. The target implementations for Streams is spdy/3.1, http2, and sshv2.

Why is this useful?

Building complex networked applications which require many streams of communication is hard. Creating and managing these streams of communication is challenging and further complicated by the desire to support multiple protocols and the need for debugging. Creating a simple interface for using these protocols not only allows simplification of management, but also makes writing debugging tools and handlers easier. Initially setting up the multiplexing protocol is only necessary to do once per connection in a complex application. However creating streams is a constant operation with low overhead to the protocol but has a high management cost to the application as the streams accumulate. A simple interface to manage these accumulating streams makes working with streams more productive.

Interface

type Stream interface {
	io.ReadWriteCloser
	Headers() http.Header
	Reset() error
}

type Listener interface {
	Accept() (Stream, error)
}

type StreamProvider interface {
	NewStream(http.Header) (Stream, error)
	Close() error
	Listen(StreamHandler) Listener
}

Multiplexing Protocols

Spdy/3.1

Implementation using github.com/docker/spdystream

HTTP/2

Future implementation using golang's http2 library

SSH

Future implementation using github.com/golang/crypto/ssh

Simple Framer

Naive framing protocol intended to implement the streams interface with minimal protocol on top of a raw byte stream

TBD: Simple framer definition

Wrappers

The implementation of the stream provider may wrap another implementation to provide additional features. These additional features may be used to span multiple connections or add debugging.