go-sockopts

Use network socket options easily on Go.

Features

• Simple
• Easy to use
• Apply multiple socket options
• Control function for net.Listener
• Custom option
• Multi platform support

Usages

Basic usage of single option

With this library, socket options can be easily set.

With the library:

// Single socket option with this library.
lc := &net.ListenConfig{
    Control: sockopts.SO_REUSEPORT.SetFunc(true).Control,
}

Without library:

// Single socket option without this library.
// Codes depends on platforms because the example uses `unix` package.
lc := &net.ListenConfig{
    Control: func(network, address string, c syscall.RawConn) error {
        var inner, outer error
        outer = c.Control(func(fd uintptr) {
            inner = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_REUSEPORT, 1)
        })
        return cmp.Or(inner, outer)
    },
}

Basic usage of multiple options

With the library:

// Multiple socket options with this library.
lc := &net.ListenConfig{
    Control: sockopts.Control(
        sockopts.SO_REUSEADDR.SetFunc(true),
        sockopts.SO_REUSEPORT.SetFunc(true),
    ),
}

Without library:

// Multiple socket options without this library.
// Codes depends on platforms because the example uses `unix` package.
lc := &net.ListenConfig{
    Control: func(network, address string, c syscall.RawConn) error {
        var inner1, inner2, outer error
        outer = c.Control(func(fd uintptr) {
            inner1 = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_REUSEADDR, 1)
            inner2 = unix.SetsockoptInt(int(fd), unix.SOL_SOCKET, unix.SO_REUSEPORT, 1)
        })
        return cmp.Or(inner1, inner2, outer)
    },
}

Run a server with SO_REUSEPORT

SO_REUSEPORT is one of the popular socket option to sahre the same port from multiple applications.

lc := &net.ListenConfig{
    Control: sockopts.SO_REUSEPORT.SetFunc(true).Control,
}

ln, err := lc.Listen(context.Background(), "tcp", ":8080")
if err != nil {
    panic(err)
}

svr := &http.Server{
    Handler: http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        w.Write([]byte("Hello Gopher !!"))
    }),
}

if err := svr.Serve(ln); err != nil && err != http.ErrServerClosed {
    panic(err)
}

Custom option

Custom options can be easily defined. Choose appropriate data type and level/opt.

The Name field is used in error messages.

var SO_KEEPALIVE = sockopts.Bool{
    Level: unix.SOL_SOCKET,
    Opt:   unix.SO_KEEPALIVE,
    Name:  "SO_KEEPALIVE",
}

Docs & Examples

• GoDoc: https://pkg.go.dev/github.com/aileron-projects/go-sockopts
• Examples:
  • Use single option: examples/single_opt/
  • Use multiple options: examples/multiple_opts/
  • Custom option: examples/custom/
  • SO_REUSEADDR: examples/reuseaddr/
  • SO_REUSEPORT: examples/reuseport/

References