Add ssh key authentication when cloning via ssh

pkg/config.go

@@ -16,6 +16,8 @@ const (
 	DefReposRoot   = "repositories"
 	KeyDefaultHost = "defaultHost"
 	DefDefaultHost = "github.com"
+	KeyPrivateKey  = "privateKey"
+	DefPrivateKey  = "id_rsa"
 )
 
 // gitconfig provides methods for looking up configiration values inside .gitconfig file
@@ -56,6 +58,10 @@ func setMissingValues(cfg *gitconfig) {
 	if isUnsetOrEmpty(KeyDefaultHost) {
 		viper.Set(KeyDefaultHost, cfg.get(KeyDefaultHost, DefDefaultHost))
 	}
+
+	if isUnsetOrEmpty(KeyPrivateKey) {
+		viper.Set(KeyPrivateKey, cfg.get(KeyPrivateKey, path.Join(home(), ".ssh", DefPrivateKey)))
+	}
 }
 
 // get looks up the value for a given key in gitconfig file.

pkg/repo.go

@@ -3,13 +3,18 @@ package pkg
 import (
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net/url"
 	"os"
 	"path"
 
 	"github.com/pkg/errors"
+	"github.com/spf13/viper"
+	"golang.org/x/crypto/ssh"
 
 	"github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/plumbing/transport"
+	go_git_ssh "github.com/go-git/go-git/v5/plumbing/transport/ssh"
 )
 
 type Repo struct {
@@ -19,25 +24,33 @@ type Repo struct {
 }
 
 func CloneRepo(url *url.URL, reposRoot string, quiet bool) (*Repo, error) {
-	repoSubPath := URLToPath(url)
-	repoPath := path.Join(reposRoot, repoSubPath)
+	repoPath := path.Join(reposRoot, URLToPath(url))
 
-	var output io.Writer
+	var progress io.Writer
 	if !quiet {
-		output = os.Stdout
+		progress = os.Stdout
 		fmt.Printf("Cloning into '%s'...\n", repoPath)
 	}
 
+	// TODO: can this be cleaner?
+	var auth transport.AuthMethod
+	var err error
+	if url.Scheme == "ssh" {
+		if auth, err = sshKeyAuth(); err != nil {
+			return nil, err
+		}
+	}
+
 	opts := &git.CloneOptions{
 		URL:               url.String(),
-		Auth:              nil,
+		Auth:              auth,
 		RemoteName:        git.DefaultRemoteName,
 		ReferenceName:     "",
 		SingleBranch:      false,
 		NoCheckout:        false,
 		Depth:             0,
 		RecurseSubmodules: git.NoRecurseSubmodules,
-		Progress:          output,
+		Progress:          progress,
 		Tags:              git.AllTags,
 	}
 
@@ -82,3 +95,20 @@ func (r *Repo) Fetch() error {
 
 	return nil
 }
+
+func sshKeyAuth() (transport.AuthMethod, error) {
+	privateKey := viper.GetString(KeyPrivateKey)
+	sshKey, err := ioutil.ReadFile(privateKey)
+	if err != nil {
+		return nil, errors.Wrapf(err, "Failed to open ssh private key %s", privateKey)
+	}
+
+	signer, err := ssh.ParsePrivateKey([]byte(sshKey))
+	if err != nil {
+		return nil, errors.Wrapf(err, "Failed to parse ssh private key %s", privateKey)
+	}
+
+	// TODO: can it ba a different user
+	auth := &go_git_ssh.PublicKeys{User: "git", Signer: signer}
+	return auth, nil
+}