updating git clone logic to support tags and switching from pull to f…

…etch and checkout by hash

Signed-off-by: Adam D. Cornett <adc@redhat.com>

internal/reconcilers/pipeline_git_repo.go

@@ -5,12 +5,14 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"github.com/redhat-openshift-ecosystem/operator-certification-operator/api/v1alpha1"
 	"github.com/redhat-openshift-ecosystem/operator-certification-operator/internal/errors"
 
 	"github.com/go-git/go-git/v5"
 	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/storer"
 	"github.com/go-logr/logr"
 	"k8s.io/apimachinery/pkg/runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
@@ -52,31 +54,65 @@ func (r *PipelineGitRepoReconciler) Reconcile(_ context.Context, pipeline *v1alp
 	return false, nil
 }
 
-func cloneOrPullRepo(targetPath string, branchName string) (string, error) {
+func cloneOrPullRepo(targetPath string, pipelineRelease string) (string, error) {
 	// Try to clone first
-	_, err := git.PlainClone(targetPath, false, &git.CloneOptions{
-		URL:           operatorPipelinesRepo,
-		ReferenceName: plumbing.NewBranchReferenceName(branchName),
+	r, err := git.PlainClone(targetPath, false, &git.CloneOptions{
+		URL: operatorPipelinesRepo,
 	})
 	if err != nil && err != git.ErrRepositoryAlreadyExists {
 		return "", err
 	}
 	// The directory is already there, so let's just update to latest
-	r, err := git.PlainOpen(targetPath)
-	if err != nil {
+	if r == nil && err == git.ErrRepositoryAlreadyExists {
+		var err error
+		r, err = git.PlainOpen(targetPath)
+		if err != nil {
+			return "", err
+		}
+	}
+
+	// If r is nil both clone and open were unsuccessful, returning err to avoid a later panic
+	if r == nil {
+		return "", fmt.Errorf("could not clone or open repo")
+	}
+
+	// Fetching to ensure repo on disk is up to date before we checkout
+	if err := r.Fetch(&git.FetchOptions{Tags: git.AllTags}); err != nil && err != git.NoErrAlreadyUpToDate {
 		return "", err
 	}
-	w, err := r.Worktree()
+
+	var ref *plumbing.Reference
+	iter, err := r.References()
 	if err != nil {
 		return "", err
 	}
-	err = w.Pull(&git.PullOptions{RemoteName: "origin"})
-	if err != nil && err != git.NoErrAlreadyUpToDate {
+
+	// Iterating over all the references to ensure the one requested is in the repository
+	// and to use the reference's value later properly checkout the requested branch/tag
+	if err := iter.ForEach(func(reference *plumbing.Reference) error {
+		if !strings.HasSuffix(reference.Name().Short(), pipelineRelease) {
+			return nil
+		}
+		ref = reference
+		return storer.ErrStop
+	}); err != nil {
 		return "", err
 	}
-	ref, err := r.Head()
+
+	if ref == nil {
+		return "", fmt.Errorf("requested release is not in repository")
+	}
+
+	// Get the worktree
+	w, err := r.Worktree()
 	if err != nil {
 		return "", err
 	}
+
+	// Checking out the hash value of the branch/tag that was requested
+	if err := w.Checkout(&git.CheckoutOptions{Hash: ref.Hash()}); err != nil {
+		return "", err
+	}
+
 	return ref.Hash().String(), nil
 }