cat2neat / gtcp

Go TCP server framework that inherits battle-tested code from net/http and can be extended through built-in interfaces.

gtcp

Package gtcp is a TCP server framework that inherits battle-tested code from net/http and can be extended through built-in interfaces.

Features

• Can be used in the same manner with http.Server(>= 1.8).

  • Make API as much compatible as possible.
  • Make the zero value useful.

• Inherits as much battle tested code from net/http.

• Provides much flexiblity through built-in interfaces.

  • ConnHandler
    • ConnHandler
    • KeepAliveHandler that makes it easy to implement keepalive.
    • PipelineHandler that makes it easy to implement pipelining.
  • ConnTracker
    • MapConnTracker that handles force closing active connections also graceful shutdown.
    • WGConnTracker that handles only graceful shutdown using a naive way with sync.WaitGroup.
  • Conn
    • BufferedConn that wraps Conn in bufio.Reader/Writer.
    • StatsConn that wraps Conn to measure incomming/outgoing bytes.
    • DebugConn that wraps Conn to output debug information.
  • Logger
    • BuiltinLogger that logs using standard log package.
  • Retry
    • ExponentialRetry that implements exponential backoff algorithm without jitter.
  • Statistics
    • TrafficStatistics that measures incomming/outgoing traffic across a server.
  • Limiter
    • MaxConnLimiter that limits connections based on the maximum number.

• Gets GC pressure as little as possible with sync.Pool.

• Zero 3rd party depentencies.

TODO

• Support TLS

• Support multiple listeners

Example

import "github.com/cat2neat/gtcp"

// echo server:
// https://tools.ietf.org/html/rfc862
func echoServer() error {
	srv := &gtcp.Server{
		Addr:    ":1979",
		NewConn: gtcp.NewStatsConn,
		ConnHandler: func(ctx context.Context, conn gtcp.Conn) {
			buf := make([]byte, 1024)
			for {
				n, err := conn.Read(buf)
				if err != nil {
					return
				}
				conn.Write(buf[:n])
				err = conn.Flush()
				if err != nil {
					return
				}
				select {
				case <-ctx.Done():
					// canceled by parent
					return
				default:
				}
			}
		},
	}
	return srv.ListenAndServe()
}

Install

go get -u github.com/cat2neat/gtcp

gtcp's Issues

conn: BaseConn should be package private

docs: Add README.md

example: for users

subset

• memcached
• redis

Outstanding connection API for ConnTracker

Hi,

May i ask if it makes sense to add a OutstandingConnection() int API to ConnTracker ? If it does, i can do one PR.

Thank you !

conn: Implement Peek for baseConn

Implementing Peek for baseConn to prevent from panic.
Call net.Conn.Read and cache the result byte retrieved into an inner field for later baseConn.Read ops.

server: Notify children when listener closed

via context

test: test server should listen on system-chosen port to avoid port conflict

so also need to publish listener.Addr I/F for test clients.

conn: sync.Pool for BaseConn

in order to reduce GC pressure.

docs: Add comments for every public API

test: Benchmark echo server

• raw socket
• ConnHandler
• KeepAliveHandler
• PipelineHandler

server: support multiple listeners

server: support TLS

handler: interface{} is more desirable rather than []byte as a bridge between pr and pw

Given that a more practical protocol on top of gtcp,
Interface{} would be desirable as a bridge between Pipeline(Reader|Writer).

Files missing copyright notices

The individual files are missing copyright notices about licensing. Each file should be begin with a copyright notice and an optional reference to the license file.