guesslicense.go

package main

import (
	"bufio"
	"errors"
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"strings"

	"github.com/ryanuber/go-license"
)

func die(v interface{}) {
	fmt.Fprintln(os.Stderr, v)
	os.Exit(1)
}

func main() {
	var packages []string

	scanner := bufio.NewScanner(os.Stdin)

	for scanner.Scan() {
		packages = append(packages, scanner.Text())
	}

	if err := scanner.Err(); err != nil {
		die(err)
	}

	for _, pkg := range packages {
		if !strings.HasPrefix(pkg, "github.com/") {
			fmt.Printf("%s\t(error, packages hosted on github are currently supported)\n", pkg)
			continue
		}

		project := strings.TrimPrefix(pkg, "github.com/")

		licenses := []string{
			"https://raw.githubusercontent.com/" + project + "/master/LICENSE",
			"https://raw.githubusercontent.com/" + project + "/master/LICENSE.txt",
			"https://raw.githubusercontent.com/" + project + "/master/LICENSE.md",
			"https://raw.githubusercontent.com/" + project + "/master/License",
		}

		var p []byte
		var e error

		for _, l := range licenses {
			resp, err := http.Get(l)
			if resp.StatusCode != 200 && err == nil {
				resp.Body.Close()
				err = errors.New(http.StatusText(resp.StatusCode))
			}
			if err != nil {
				e = err
				continue
			}

			p, e = ioutil.ReadAll(resp.Body)
			resp.Body.Close()
			if e == nil {
				break
			}
		}

		if len(p) == 0 || e != nil {
			fmt.Printf("%s\t(%s)\n", pkg, e)
			continue
		}

		lic := license.New("", string(p))

		if err := lic.GuessType(); err != nil {
			fmt.Printf("%s\t(%s)\n", pkg, err)
			continue
		}

		fmt.Printf("%s\t%s\n", pkg, lic.Type)
	}
}

go list -f '{{join .Deps "\n"}}' koding/klient | grep -E '^(github|golang|gopkg)' | cut -d/ -f1,2,3 | sort -u | go run ~/guesslicense.go 
github.com/aws/aws-sdk-go   Apache-2.0
...