feat: support to checkout github pr (#12)

* feat: support to checkout github pr

* fix the auth issues

* support to checkout branch

* add more unit tests

Co-authored-by: rick <[email protected]>

.gitignore

@@ -1,3 +1,4 @@
 bin/
 dist/
 .idea/
+coverage.out

Makefile

@@ -4,6 +4,7 @@ copy: build
 	cp bin/gogit /usr/local/bin
 test:
 	go test ./... -coverprofile coverage.out
+pre-commit: test
 goreleaser:
 	goreleaser build --snapshot --rm-dist
 image:

README.md

@@ -6,6 +6,17 @@
 * Gitlab (public or private)
 
 ## Usage
+
+### Checkout to branch or PR
+Ideally, `gogit` could checkout to your branch or PR in any kind of git repository.
+
+You can run the following command in a git repository directory:
+
+```shell
+gogit checkout --pr 1
+```
+
+### Send status to Git Provider
 Below is an example of sending build status to a private Gitlab server:
 
 ```shell

cmd/checkout.go

@@ -2,21 +2,25 @@ package cmd
 
 import (
 	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
 	"github.com/go-git/go-git/v5"
 	"github.com/go-git/go-git/v5/config"
 	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/transport"
 	"github.com/go-git/go-git/v5/plumbing/transport/ssh"
 	"github.com/spf13/cobra"
-	"os"
-	"path/filepath"
 )
 
 func newCheckoutCommand() (c *cobra.Command) {
 	opt := &checkoutOption{}
 
 	c = &cobra.Command{
 		Use:     "checkout",
-		Short:   "Clond and checkout the git repository with branch, tag, or pull request",
+		Aliases: []string{"co"},
+		Short:   "Clone and checkout the git repository with branch, tag, or pull request",
 		Example: "gogit checkout https://github.com/linuxsuren/gogit",
 		PreRunE: opt.preRunE,
 		RunE:    opt.runE,
@@ -25,6 +29,8 @@ func newCheckoutCommand() (c *cobra.Command) {
 	flags := c.Flags()
 	flags.StringVarP(&opt.url, "url", "", "", "The git repository URL")
 	flags.StringVarP(&opt.remote, "remote", "", "origin", "The remote name")
+	flags.StringVarP(&opt.sshPrivateKey, "ssh-private-key", "", "$HOME/.ssh/id_rsa",
+		"The SSH private key file path")
 	flags.StringVarP(&opt.branch, "branch", "", "master", "The branch want to checkout")
 	flags.StringVarP(&opt.tag, "tag", "", "", "The tag want to checkout")
 	flags.IntVarP(&opt.pr, "pr", "", -1, "The pr number want to checkout, -1 means do nothing")
@@ -45,70 +51,120 @@ func (o *checkoutOption) runE(c *cobra.Command, args []string) (err error) {
 	if repoDir, err = filepath.Abs(o.target); err != nil {
 		return
 	}
-	rsa := os.ExpandEnv("$HOME/.ssh/id_rsa")
 
-	var publicKeys *ssh.PublicKeys
-	if publicKeys, err = ssh.NewPublicKeysFromFile("git", rsa, ""); err != nil {
+	var gitAuth transport.AuthMethod
+	if gitAuth, err = o.getAuth(o.url); err != nil {
 		return
 	}
 
-	if _, err = git.PlainClone(repoDir, false, &git.CloneOptions{
-		RemoteName:    o.remote,
-		Auth:          publicKeys,
-		URL:           o.url,
-		ReferenceName: plumbing.NewBranchReferenceName(o.branch),
-		Progress:      c.OutOrStdout(),
-	}); err != nil {
-		err = fmt.Errorf("failed to clone git repository '%s' into '%s', error: %v", o.url, repoDir, err)
+	var repo *git.Repository
+	if _, serr := os.Stat(filepath.Join(repoDir, ".git")); serr != nil {
+		if repo, err = git.PlainCloneContext(c.Context(), repoDir, false, &git.CloneOptions{
+			RemoteName:    o.remote,
+			Auth:          gitAuth,
+			URL:           o.url,
+			ReferenceName: plumbing.NewBranchReferenceName(o.branch),
+			Progress:      c.OutOrStdout(),
+		}); err != nil {
+			err = fmt.Errorf("failed to clone git repository '%s' into '%s', error: %v", o.url, repoDir, err)
+			return
+		}
+	} else if repo, err = git.PlainOpen(repoDir); err != nil {
 		return
 	}
 
-	var repo *git.Repository
-	if repo, err = git.PlainOpen(repoDir); err == nil {
-		var wd *git.Worktree
-
-		if wd, err = repo.Worktree(); err == nil {
-			if o.tag != "" {
-				if err = wd.Checkout(&git.CheckoutOptions{
-					Branch: plumbing.NewTagReferenceName(o.tag),
-				}); err != nil {
-					err = fmt.Errorf("unable to checkout git branch: %s, error: %v", o.tag, err)
-					return
-				}
+	var wd *git.Worktree
+	var remotes []*git.Remote
+
+	if remotes, err = repo.Remotes(); err != nil {
+		return
+	}
+
+	remoteURL := remotes[0].Config().URLs[0]
+	kind := detectGitKind(remoteURL)
+	// need to get auth again if the repo was exist
+	if gitAuth, err = o.getAuth(remoteURL); err != nil {
+		return
+	}
+
+	if wd, err = repo.Worktree(); err == nil {
+		if c.Flags().Changed("branch") {
+			c.Printf("Switched to branch '%s'\n", o.branch)
+
+			if err = wd.Checkout(&git.CheckoutOptions{
+				Branch: plumbing.NewBranchReferenceName(o.branch),
+			}); err != nil {
+				err = fmt.Errorf("unable to checkout git branch: %s, error: %v", o.branch, err)
+				return
 			}
+		}
 
-			if o.pr > 0 {
-				// TODO add GitHub support, see also https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally?gt
-				if err = repo.Fetch(&git.FetchOptions{
-					RemoteName: o.remote,
-					Auth:       publicKeys,
-					Progress:   c.OutOrStdout(),
-					RefSpecs:   []config.RefSpec{config.RefSpec(fmt.Sprintf("refs/merge-requests/%d/head:mr-%d", o.pr, o.pr))},
-				}); err != nil && err != git.NoErrAlreadyUpToDate {
-					err = fmt.Errorf("failed to fetch '%s', error: %v", o.remote, err)
-					return
-				}
-
-				if err = wd.Checkout(&git.CheckoutOptions{
-					Create: true,
-					Branch: plumbing.NewBranchReferenceName(fmt.Sprintf("mr-%d", o.pr)),
-				}); err != nil {
-					err = fmt.Errorf("unable to checkout git branch: %s, error: %v", o.tag, err)
-					return
-				}
+		if o.tag != "" {
+			if err = wd.Checkout(&git.CheckoutOptions{
+				Branch: plumbing.NewTagReferenceName(o.tag),
+			}); err != nil {
+				err = fmt.Errorf("unable to checkout git tag: %s, error: %v", o.tag, err)
+				return
 			}
+		}
 
-			var head *plumbing.Reference
-			if head, err = repo.Head(); err == nil {
-				if o.versionOutput != "" {
-					os.WriteFile(o.versionOutput, []byte(head.Name().Short()), 0444)
-				}
+		if o.pr > 0 {
+			if err = repo.Fetch(&git.FetchOptions{
+				RemoteName: o.remote,
+				Auth:       gitAuth,
+				Progress:   c.OutOrStdout(),
+				RefSpecs:   []config.RefSpec{config.RefSpec(prRef(o.pr, kind))},
+			}); err != nil && err != git.NoErrAlreadyUpToDate {
+				err = fmt.Errorf("failed to fetch '%s', error: %v", o.remote, err)
+				return
+			}
+
+			if err = wd.Checkout(&git.CheckoutOptions{
+				Create: true,
+				Branch: plumbing.NewBranchReferenceName(fmt.Sprintf("pr-%d", o.pr)),
+			}); err != nil && !strings.Contains(err.Error(), "already exists") {
+				err = fmt.Errorf("unable to checkout git branch: %s, error: %v", o.tag, err)
+				return
+			}
+		}
+
+		var head *plumbing.Reference
+		if head, err = repo.Head(); err == nil {
+			if o.versionOutput != "" {
+				err = os.WriteFile(o.versionOutput, []byte(head.Name().Short()), 0444)
 			}
 		}
 	}
 	return
 }
 
+func (o *checkoutOption) getAuth(remote string) (auth transport.AuthMethod, err error) {
+	if strings.HasPrefix(remote, "git@") {
+		rsa := os.ExpandEnv(o.sshPrivateKey)
+		auth, err = ssh.NewPublicKeysFromFile("git", rsa, "")
+	}
+	return
+}
+
+func detectGitKind(gitURL string) (kind string) {
+	kind = "gitlab"
+	if strings.Contains(gitURL, "github.com") {
+		kind = "github"
+	}
+	return
+}
+
+// see also https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally?gt
+func prRef(pr int, kind string) (ref string) {
+	switch kind {
+	case "gitlab":
+		ref = fmt.Sprintf("refs/merge-requests/%d/head:pr-%d", pr, pr)
+	case "github":
+		ref = fmt.Sprintf("refs/pull/%d/head:pr-%d", pr, pr)
+	}
+	return
+}
+
 type checkoutOption struct {
 	url           string
 	remote        string
@@ -117,4 +173,5 @@ type checkoutOption struct {
 	pr            int
 	target        string
 	versionOutput string
+	sshPrivateKey string
 }

cmd/checkout_test.go

@@ -0,0 +1,86 @@
+package cmd
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_prRef(t *testing.T) {
+	type args struct {
+		pr   int
+		kind string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantRef string
+	}{{
+		name: "gitlab",
+		args: args{
+			pr:   1,
+			kind: "gitlab",
+		},
+		wantRef: "refs/merge-requests/1/head:pr-1",
+	}, {
+		name: "unknown",
+		args: args{
+			pr:   1,
+			kind: "unknown",
+		},
+		wantRef: "",
+	}, {
+		name: "github",
+		args: args{
+			pr:   1,
+			kind: "github",
+		},
+		wantRef: "refs/pull/1/head:pr-1",
+	}}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equalf(t, tt.wantRef, prRef(tt.args.pr, tt.args.kind), "prRef(%v, %v)", tt.args.pr, tt.args.kind)
+		})
+	}
+}
+
+func Test_detectGitKind(t *testing.T) {
+	type args struct {
+		gitURL string
+	}
+	tests := []struct {
+		name     string
+		args     args
+		wantKind string
+	}{{
+		name: "github",
+		args: args{
+			gitURL: "https://github.com/linuxsuren/gogit",
+		},
+		wantKind: "github",
+	}, {
+		name: "gitlab",
+		args: args{
+			gitURL: "[email protected]:demo/test.git",
+		},
+		wantKind: "gitlab",
+	}}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equalf(t, tt.wantKind, detectGitKind(tt.args.gitURL), "detectGitKind(%v)", tt.args.gitURL)
+		})
+	}
+}
+
+func TestGetAuth(t *testing.T) {
+	opt := &checkoutOption{
+		sshPrivateKey: "/tmp",
+	}
+	auth, err := opt.getAuth("[email protected]")
+	assert.Nil(t, auth)
+	assert.NotNil(t, err)
+
+	auth, err = opt.getAuth("fake.com")
+	assert.Nil(t, auth)
+	assert.Nil(t, err)
+}

go.mod

@@ -18,16 +18,20 @@ require (
 	github.com/imdario/mergo v0.3.12 // indirect
 	github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 // indirect
 	github.com/kevinburke/ssh_config v0.0.0-20201106050909-4977a11b4351 // indirect
+	github.com/kr/pretty v0.2.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
 	github.com/sergi/go-diff v1.1.0 // indirect
 	github.com/xanzy/ssh-agent v0.3.0 // indirect
+	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 	gopkg.in/warnings.v0 v0.1.2 // indirect
 )
 
 require (
 	code.gitea.io/sdk/gitea v0.14.0 // indirect
 	github.com/bluekeyes/go-gitdiff v0.4.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-git/go-git-fixtures/v4 v4.3.1
 	github.com/go-git/go-git/v5 v5.4.2
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/hashicorp/go-version v1.3.0 // indirect

go.sum

@@ -34,6 +34,8 @@ github.com/go-git/go-billy/v5 v5.3.1 h1:CPiOUAzKtMRvolEKw+bG1PLRpT7D3LIs3/3ey4Ai
 github.com/go-git/go-billy/v5 v5.3.1/go.mod h1:pmpqyWchKfYfrkb/UVH4otLvyi/5gJlGI4Hb3ZqZ3W0=
 github.com/go-git/go-git-fixtures/v4 v4.2.1 h1:n9gGL1Ct/yIw+nfsfr8s4+sbhT+Ncu2SubfXjIWgci8=
 github.com/go-git/go-git-fixtures/v4 v4.2.1/go.mod h1:K8zd3kDUAykwTdDCr+I0per6Y6vMiRR/nnVTBtavnB0=
+github.com/go-git/go-git-fixtures/v4 v4.3.1 h1:y5z6dd3qi8Hl+stezc8p3JxDkoTRqMAlKnXHuzrfjTQ=
+github.com/go-git/go-git-fixtures/v4 v4.3.1/go.mod h1:8LHG1a3SRW71ettAD/jW13h8c6AqjVSeL11RAdgaqpo=
 github.com/go-git/go-git/v5 v5.4.2 h1:BXyZu9t0VkbiHtqrsvdq39UDhGJTl1h55VW6CSC4aY4=
 github.com/go-git/go-git/v5 v5.4.2/go.mod h1:gQ1kArt6d+n+BGd+/B/I74HwRTLhth2+zti4ihgckDc=
 github.com/gogo/protobuf v1.0.0/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=