Quick Start

gogetway is a Go framework for building TCP/HTTP gateways with traffic recording, replay, and passive mirroring.

This page walks you through the three most common usage patterns in 5 minutes.

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1. Install

go get github.com/wangshiben/gogetway

If you just want a ready-made proxy CLI, use cmd/tcp-proxy — see the Readme.

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2. Active Proxy + Recording

The simplest pattern: listen on a local port, forward to an upstream, and persist traffic to a file.

package main

import (
    "context"
    "log"
    "net"
    "os"

    "github.com/wangshiben/gogetway/getwayServer"
)

func main() {
    f, _ := os.Create("./traffic.log")
    defer f.Close()

    writeFunc := func(data []byte, ctx context.Context) (int, error) {
        log.Printf("recorded %d bytes", len(data))
        return len(data), nil
    }

    server := getwayServer.NewSimpleTCPServerWithWriterAndFunc(
        "127.0.0.1:8080", // upstream
        ":9000",           // local listen
        getwayServer.TCPType,
        f,
        writeFunc,
    )

    server.SetConnectTargetFunc(func(ctx context.Context, client net.Conn) (net.Conn, error) {
        return net.Dial("tcp", "127.0.0.1:8080")
    })

    server.StartListen() // blocking
}

Next: SimpleTCPServer in depth

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3. Traffic Replay

Replay a recorded file to a target service:

import "github.com/wangshiben/gogetway/tcpPlayback"

count, err := tcpPlayback.ReplayFileToTarget(
    "./traffic.log",
    "127.0.0.1:9999",
    false, // whether to honor original inter-packet timing
    nil,   // optional DataParser
)
log.Printf("replayed=%d err=%v", count, err)

Next: TcpPlayer in depth

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4. Passive Mirror (Zero-Deploy)

Use pcap-based capture to mirror or sidecar-record an already-deployed service:

mirror := getwayServer.NewGopacketTrafficMirror(getwayServer.GopacketMirrorConfig{
    ObservedPort: 8090,
    TargetAddr:   "127.0.0.1:18090", // sidecar target; empty = record only
    Writer:       recordFile,
})

ctx, cancel := context.WithCancel(context.Background())
defer cancel()
mirror.Start(ctx, mySource) // mySource implements ObservedPacketSource

Next: GopacketTrafficMirror in depth

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5. Doc Index

Topic	Page
Active proxy (listen + forward + record)	SimpleTCPServer
Passive mirror (pcap capture)	GopacketTrafficMirror
Traffic replay	TcpPlayer
Resource-pool abstraction	ConnectResource / ResourceGroup
Lock management	LockGroup
Recording protocol format	proto format