HTTP over Unix domain sockets in golang

unixhttpc.go

package main

import (
	"context"
	"flag"
	"fmt"
	"io"
	"net"
	"net/http"
	"os"
	"strings"
)

func main() {
	post := flag.String("d", "", "data to POST")
	help := flag.Bool("h", false, "usage help")
	flag.Parse()

	if *help || len(flag.Args()) != 2 {
		fmt.Fprintln(os.Stderr, "usage:", os.Args[0], "[-d data] /path.socket /uri")
		flag.PrintDefaults()
		os.Exit(0)
	}

	fmt.Println("Unix HTTP client")

	httpc := http.Client{
		Transport: &http.Transport{
			DialContext: func(_ context.Context, _, _ string) (net.Conn, error) {
				return net.Dial("unix", flag.Args()[0])
			},
		},
	}

	var response *http.Response
	var err error
	if len(*post) == 0 {
		response, err = httpc.Get("http://unix" + flag.Args()[1])
	} else {
		response, err = httpc.Post("http://unix"+flag.Args()[1], "application/octet-stream", strings.NewReader(*post))
	}

	if err != nil {
		panic(err)
	}
	io.Copy(os.Stdout, response.Body)
}

unixhttpd.go

package main

import (
	"fmt"
	"net"
	"net/http"
	"os"
)

func main() {
	if len(os.Args) < 2 {
		fmt.Fprintln(os.Stderr, "usage:", os.Args[0], "/path.sock [wwwroot]")
		return
	}

	fmt.Println("Unix HTTP server")

	root := "."
	if len(os.Args) > 2 {
		root = os.Args[2]
	}

	os.Remove(os.Args[1])

	server := http.Server{
		Handler: http.FileServer(http.Dir(root)),
	}

	unixListener, err := net.Listen("unix", os.Args[1])
	if err != nil {
		panic(err)
	}
	server.Serve(unixListener)
}

Thanks!

To preserve the context, I would recommend:

				DialContext: func(ctx context.Context, _, addr string) (net.Conn, error) {
					dialer := net.Dialer{} // don't know why we need a struct to use DialContext()
					return dialer.DialContext(ctx, "unix", flag.Args()[0])
				},

I know this is like, 3 years late, but you need to store it as a variable because DialContext belongs to (*Dialer) not (Dialer). When you assign it a local value, it can be referenced as *Dialer. A way around this, is to do this:

return (&net.Dialer{}).DialContext(ctx, "unix", flags.Args()[0])

I like this. Might be worthwhile mentioning the benefits.

Thanks a lot!

Are you sure you can handle the response? response.Body is always empty in my code but I can detect errors or responses at my socket application.

Thank you!

Helped a lot here!