cmd: add draft-init command

draft-init/main.go

@@ -0,0 +1,132 @@
+package main
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"strings"
+)
+
+type ServiceAccount struct {
+	Type                    string `json:"type"`
+	ProjectID               string `json:"project_id"`
+	PrivateKeyID            string `json:"private_key_id"`
+	PrivateKey              string `json:"private_key"`
+	ClientEmail             string `json:"client_email"`
+	ClientID                string `json:"client_id"`
+	AuthURI                 string `json:"auth_uri"`
+	TokenURI                string `json:"token_uri"`
+	AuthProviderX509CertURL string `json:"auth_provider_x509_cert_url"`
+	ClientX509CertURL       string `json:"client_x509_cert_url"`
+}
+
+type RegistryAuth struct {
+	Username string `json:"username"`
+	Password string `json:"password"`
+	Email    string `json:"email"`
+}
+
+type options struct {
+	file   string
+	domain string
+	gcr    string
+	dry    bool
+}
+
+func (opts *options) RegisterFlags(f *flag.FlagSet) {
+	f.StringVar(&opts.file, "f", "", "Service account JSON key file.")
+	f.StringVar(&opts.domain, "domain", "", "Base domain for applications.")
+	f.StringVar(&opts.gcr, "gcr", "gcr.io", "Container registry host.")
+	f.BoolVar(&opts.dry, "dry", false, "Print commands only.")
+}
+func die(v ...interface{}) {
+	fmt.Fprintln(os.Stderr, v...)
+	os.Exit(1)
+}
+
+func main() {
+	var opts options
+	opts.RegisterFlags(flag.CommandLine)
+	flag.Parse()
+
+	if err := run(&opts); err != nil {
+		die(err)
+	}
+}
+
+func run(opts *options) error {
+	pass, err := ioutil.ReadFile(opts.file)
+	if err != nil {
+		return err
+	}
+
+	var cert ServiceAccount
+	if err := json.Unmarshal(pass, &cert); err != nil {
+		return err
+	}
+	if pass, err = json.Marshal(&cert); err != nil {
+		return err
+	}
+
+	auth := &RegistryAuth{
+		Username: "_json_key",
+		Password: string(pass),
+		Email:    "not@val.id",
+	}
+
+	p, err := json.Marshal(auth)
+	if err != nil {
+		return err
+	}
+
+	token := base64.StdEncoding.EncodeToString(p)
+
+	draftConfig := []string{
+		"registry.url=" + opts.gcr,
+		"registry.org=" + cert.ProjectID,
+		"registry.authtoken=" + token,
+	}
+
+	if opts.domain != "" {
+		draftConfig = append(draftConfig, "basedomain="+opts.domain)
+	}
+
+	draftArgs := []string{
+		"init",
+		"--set", strings.Join(draftConfig, ","),
+	}
+
+	dockerArgs := []string{
+		"login",
+		"-e", auth.Email,
+		"-u", auth.Username,
+		"-p", auth.Password,
+		opts.gcr,
+	}
+
+	draft := cmd("draft", draftArgs...)
+	docker := cmd("docker", dockerArgs...)
+
+	if opts.dry {
+		fmt.Fprintln(os.Stderr, docker.Args)
+		fmt.Fprintln(os.Stderr, draft.Args)
+		return nil
+	}
+
+	if err := docker.Run(); err != nil {
+		return err
+	}
+
+	return draft.Run()
+}
+
+func cmd(name string, args ...string) *exec.Cmd {
+	c := exec.Command(name, args...)
+	c.Stdout = os.Stdout
+	c.Stderr = os.Stderr
+	return c
+}