From 192848fe20fcae77894b0d9bc03b87e574b1403f Mon Sep 17 00:00:00 2001
From: Shane Lattanzio <slattanzio@pivotal.io>
Date: Mon, 30 Oct 2023 16:54:52 -0400
Subject: [PATCH] Make cloning conditional on subpaths and rename methods

---
 pkg/git/remote_git_resolver.go | 91 +++++++++++++++++++++++++---------
 1 file changed, 68 insertions(+), 23 deletions(-)

diff --git a/pkg/git/remote_git_resolver.go b/pkg/git/remote_git_resolver.go
index a36bdda44..f96acde98 100644
--- a/pkg/git/remote_git_resolver.go
+++ b/pkg/git/remote_git_resolver.go
@@ -1,24 +1,30 @@
 package git
 
 import (
+	"regexp"
+	"strings"
+
 	gogit "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/storage/memory"
 	corev1alpha1 "github.com/pivotal/kpack/pkg/apis/core/v1alpha1"
-	"regexp"
-	"strings"
 )
 
+const defaultRemote = "origin"
+
 type remoteGitResolver struct{}
 
 func (*remoteGitResolver) Resolve(auth transport.AuthMethod, sourceConfig corev1alpha1.SourceConfig) (corev1alpha1.ResolvedSourceConfig, error) {
 	var resolvedConfig corev1alpha1.ResolvedSourceConfig
+	var err error
 
-	r, err := gogit.Clone(memory.NewStorage(), nil, &gogit.CloneOptions{
-		URL:  sourceConfig.Git.URL,
-		Auth: auth,
-	})
+	if sourceConfig.SubPath != "" {
+		resolvedConfig, err = resolveSourceWithSubpath(auth, sourceConfig)
+	} else {
+		resolvedConfig, err = resolveSourceWithoutSubpath(auth, sourceConfig)
+	}
 
 	if err != nil {
 		resolvedConfig = corev1alpha1.ResolvedSourceConfig{
@@ -32,6 +38,55 @@ func (*remoteGitResolver) Resolve(auth transport.AuthMethod, sourceConfig corev1
 		}
 	}
 
+	if resolvedConfig.ResolvedSource() == nil {
+		resolvedConfig = corev1alpha1.ResolvedSourceConfig{
+			Git: &corev1alpha1.ResolvedGitSource{
+				URL:                  sourceConfig.Git.URL,
+				Revision:             sourceConfig.Git.Revision,
+				Type:                 corev1alpha1.Commit,
+				SubPath:              sourceConfig.SubPath,
+				InitializeSubmodules: sourceConfig.Git.InitializeSubmodules,
+			},
+		}
+	}
+
+	return resolvedConfig, err
+}
+
+func resolveSourceWithoutSubpath(auth transport.AuthMethod, sourceConfig corev1alpha1.SourceConfig) (corev1alpha1.ResolvedSourceConfig, error) {
+	remote := gogit.NewRemote(memory.NewStorage(), &config.RemoteConfig{
+		Name: defaultRemote,
+		URLs: []string{sourceConfig.Git.URL},
+	})
+
+	refs, err := remote.List(&gogit.ListOptions{
+		Auth: auth,
+	})
+
+	for _, ref := range refs {
+		if ref.Name().Short() == sourceConfig.Git.Revision {
+			return corev1alpha1.ResolvedSourceConfig{
+				Git: &corev1alpha1.ResolvedGitSource{
+					URL:                  sourceConfig.Git.URL,
+					Revision:             ref.Hash().String(),
+					Type:                 sourceType(ref),
+					SubPath:              sourceConfig.SubPath,
+					InitializeSubmodules: sourceConfig.Git.InitializeSubmodules,
+				},
+			}, nil
+		}
+	}
+	return corev1alpha1.ResolvedSourceConfig{}, err
+}
+
+func resolveSourceWithSubpath(auth transport.AuthMethod, sourceConfig corev1alpha1.SourceConfig) (corev1alpha1.ResolvedSourceConfig, error) {
+	var resolvedConfig corev1alpha1.ResolvedSourceConfig
+
+	r, err := gogit.Clone(memory.NewStorage(), nil, &gogit.CloneOptions{
+		URL:  sourceConfig.Git.URL,
+		Auth: auth,
+	})
+
 	rIter, _ := r.References()
 
 	rIter.ForEach(func(ref *plumbing.Reference) error {
@@ -40,7 +95,7 @@ func (*remoteGitResolver) Resolve(auth transport.AuthMethod, sourceConfig corev1
 			effectiveCommit := ""
 
 			if refSourceType == corev1alpha1.Branch {
-				effectiveCommit, err = getLogs(r, sourceConfig.SubPath)
+				effectiveCommit, err = latestCommitForSubpath(r, sourceConfig.SubPath)
 			} else {
 				effectiveCommit = ref.Hash().String()
 			}
@@ -51,31 +106,21 @@ func (*remoteGitResolver) Resolve(auth transport.AuthMethod, sourceConfig corev1
 
 			resolvedConfig = corev1alpha1.ResolvedSourceConfig{
 				Git: &corev1alpha1.ResolvedGitSource{
-					URL:      sourceConfig.Git.URL,
-					Revision: effectiveCommit,
-					Type:     refSourceType,
-					SubPath:  sourceConfig.SubPath,
+					URL:                  sourceConfig.Git.URL,
+					Revision:             effectiveCommit,
+					Type:                 refSourceType,
+					SubPath:              sourceConfig.SubPath,
+					InitializeSubmodules: sourceConfig.Git.InitializeSubmodules,
 				},
 			}
 		}
 		return nil
 	})
 
-	if resolvedConfig.ResolvedSource() == nil {
-		resolvedConfig = corev1alpha1.ResolvedSourceConfig{
-			Git: &corev1alpha1.ResolvedGitSource{
-				URL:      sourceConfig.Git.URL,
-				Revision: sourceConfig.Git.Revision,
-				Type:     corev1alpha1.Commit,
-				SubPath:  sourceConfig.SubPath,
-			},
-		}
-	}
-
 	return resolvedConfig, err
 }
 
-func getLogs(r *gogit.Repository, subPath string) (string, error) {
+func latestCommitForSubpath(r *gogit.Repository, subPath string) (string, error) {
 	logOutput, err := r.Log(&gogit.LogOptions{
 		PathFilter: func(s string) bool {
 			if strings.Contains(s, subPath) {