Add an api endpoint to fetch git notes (#15373) (#16649)

close #15373

3 files changed, 32 insertions, 1 deletions

diff --git a/modules/git/notes_gogit.go b/modules/git/notes_gogit.go
index 702754069b..9da45ca65c 100644
--- a/modules/git/notes_gogit.go
+++ b/modules/git/notes_gogit.go
@@ -10,19 +10,24 @@ import (
 	"context"
 	"io/ioutil"
 
+	"code.gitea.io/gitea/modules/log"
+
 	"github.com/go-git/go-git/v5/plumbing/object"
 )
 
 // GetNote retrieves the git-notes data for a given commit.
 func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note) error {
+	log.Trace("Searching for git note corresponding to the commit %q in the repository %q", commitID, repo.Path)
 	notes, err := repo.GetCommit(NotesRef)
 	if err != nil {
+		log.Error("Unable to get commit from ref %q. Error: %v", NotesRef, err)
 		return err
 	}
 
 	remainingCommitID := commitID
 	path := ""
 	currentTree := notes.Tree.gogitTree
+	log.Trace("Found tree with ID %q while searching for git note corresponding to the commit %q", currentTree.Entries[0].Name, commitID)
 	var file *object.File
 	for len(remainingCommitID) > 2 {
 		file, err = currentTree.File(remainingCommitID)
@@ -39,6 +44,7 @@ func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note)
 			if err == object.ErrDirectoryNotFound {
 				return ErrNotExist{ID: remainingCommitID, RelPath: path}
 			}
+			log.Error("Unable to find git note corresponding to the commit %q. Error: %v", commitID, err)
 			return err
 		}
 	}
@@ -46,12 +52,14 @@ func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note)
 	blob := file.Blob
 	dataRc, err := blob.Reader()
 	if err != nil {
+		log.Error("Unable to read blob with ID %q. Error: %v", blob.ID, err)
 		return err
 	}
 
 	defer dataRc.Close()
 	d, err := ioutil.ReadAll(dataRc)
 	if err != nil {
+		log.Error("Unable to read blob with ID %q. Error: %v", blob.ID, err)
 		return err
 	}
 	note.Message = d
@@ -68,6 +76,7 @@ func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note)
 
 	lastCommits, err := GetLastCommitForPaths(ctx, commitNode, "", []string{path})
 	if err != nil {
+		log.Error("Unable to get the commit for the path %q. Error: %v", path, err)
 		return err
 	}
 	note.Commit = convertCommit(lastCommits[path])
diff --git a/modules/git/notes_nogogit.go b/modules/git/notes_nogogit.go
index 267087a86f..697f998288 100644
--- a/modules/git/notes_nogogit.go
+++ b/modules/git/notes_nogogit.go
@@ -10,20 +10,26 @@ import (
 	"context"
 	"io/ioutil"
 	"strings"
+
+	"code.gitea.io/gitea/modules/log"
 )
 
 // GetNote retrieves the git-notes data for a given commit.
 func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note) error {
+	log.Trace("Searching for git note corresponding to the commit %q in the repository %q", commitID, repo.Path)
 	notes, err := repo.GetCommit(NotesRef)
 	if err != nil {
+		log.Error("Unable to get commit from ref %q. Error: %v", NotesRef, err)
 		return err
 	}
 
 	path := ""
 
 	tree := &notes.Tree
+	log.Trace("Found tree with ID %q while searching for git note corresponding to the commit %q", tree.ID, commitID)
 
 	var entry *TreeEntry
+	originalCommitID := commitID
 	for len(commitID) > 2 {
 		entry, err = tree.GetTreeEntryByPath(commitID)
 		if err == nil {
@@ -36,12 +42,15 @@ func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note)
 			commitID = commitID[2:]
 		}
 		if err != nil {
+			log.Error("Unable to find git note corresponding to the commit %q. Error: %v", originalCommitID, err)
 			return err
 		}
 	}
 
-	dataRc, err := entry.Blob().DataAsync()
+	blob := entry.Blob()
+	dataRc, err := blob.DataAsync()
 	if err != nil {
+		log.Error("Unable to read blob with ID %q. Error: %v", blob.ID, err)
 		return err
 	}
 	closed := false
@@ -52,6 +61,7 @@ func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note)
 	}()
 	d, err := ioutil.ReadAll(dataRc)
 	if err != nil {
+		log.Error("Unable to read blob with ID %q. Error: %v", blob.ID, err)
 		return err
 	}
 	_ = dataRc.Close()
@@ -66,6 +76,7 @@ func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note)
 
 	lastCommits, err := GetLastCommitForPaths(ctx, notes, treePath, []string{path})
 	if err != nil {
+		log.Error("Unable to get the commit for the path %q. Error: %v", treePath, err)
 		return err
 	}
 	note.Commit = lastCommits[path]
diff --git a/modules/structs/repo_note.go b/modules/structs/repo_note.go
new file mode 100644
index 0000000000..bddc945a5c
--- /dev/null
+++ b/modules/structs/repo_note.go
@@ -0,0 +1,11 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package structs
+
+// Note contains information related to a git note
+type Note struct {
+	Message string  `json:"message"`
+	Commit  *Commit `json:"commit"`
+}