Monorepo for Tangled
knotserver/git: improve lastCommit calculations for dirs and files
bigger portions of the logic for directories and files are now shared.
Signed-off-by: oppiliappan <me@oppi.li>
oppiliappan
(Feb 4, 2026, 7:31 AM UTC)
c356948c
54b89d3f
+87
-60
+87
-60
knotserver/git/last_commit.go
+87
-60
knotserver/git/last_commit.go
···
6
6
"crypto/sha256"
7
7
"fmt"
8
8
"io"
9
+
"iter"
9
10
"os/exec"
10
11
"path"
12
+
"strconv"
11
13
"strings"
12
14
"time"
13
15
14
16
"github.com/dgraph-io/ristretto"
15
17
"github.com/go-git/go-git/v5/plumbing"
16
-
"github.com/go-git/go-git/v5/plumbing/object"
18
+
"tangled.org/core/sets"
17
19
"tangled.org/core/types"
18
20
)
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21
···
73
75
type commit struct {
74
76
hash plumbing.Hash
75
77
when time.Time
76
-
files []string
78
+
files sets.Set[string]
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79
message string
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80
}
79
81
82
+
func newCommit() commit {
83
+
return commit{
84
+
files: sets.New[string](),
85
+
}
86
+
}
87
+
88
+
type lastCommitDir struct {
89
+
dir string
90
+
entries []string
91
+
}
92
+
93
+
func (l lastCommitDir) children() iter.Seq[string] {
94
+
return func(yield func(string) bool) {
95
+
for _, child := range l.entries {
96
+
if !yield(path.Join(l.dir, child)) {
97
+
return
98
+
}
99
+
}
100
+
}
101
+
}
102
+
80
103
func cacheKey(g *GitRepo, path string) string {
81
104
sep := byte(':')
82
105
hash := sha256.Sum256(fmt.Append([]byte{}, g.path, sep, g.h.String(), sep, path))
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106
return fmt.Sprintf("%x", hash)
84
107
}
85
108
86
-
func (g *GitRepo) calculateCommitTimeIn(ctx context.Context, subtree *object.Tree, parent string, timeout time.Duration) (map[string]commit, error) {
109
+
func (g *GitRepo) lastCommitDirIn(ctx context.Context, parent lastCommitDir, timeout time.Duration) (map[string]commit, error) {
87
110
ctx, cancel := context.WithTimeout(ctx, timeout)
88
111
defer cancel()
89
-
return g.calculateCommitTime(ctx, subtree, parent)
112
+
return g.lastCommitDir(ctx, parent)
90
113
}
91
114
92
-
func (g *GitRepo) calculateCommitTime(ctx context.Context, subtree *object.Tree, parent string) (map[string]commit, error) {
93
-
filesToDo := make(map[string]struct{})
115
+
func (g *GitRepo) lastCommitDir(ctx context.Context, parent lastCommitDir) (map[string]commit, error) {
116
+
filesToDo := sets.Collect(parent.children())
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117
filesDone := make(map[string]commit)
95
-
for _, e := range subtree.Entries {
96
-
fpath := path.Clean(path.Join(parent, e.Name))
97
-
filesToDo[fpath] = struct{}{}
98
-
}
99
118
100
-
for _, e := range subtree.Entries {
101
-
f := path.Clean(path.Join(parent, e.Name))
102
-
cacheKey := cacheKey(g, f)
119
+
for p := range filesToDo.All() {
120
+
cacheKey := cacheKey(g, p)
103
121
if cached, ok := commitCache.Get(cacheKey); ok {
104
-
filesDone[f] = cached.(commit)
105
-
delete(filesToDo, f)
122
+
filesDone[p] = cached.(commit)
123
+
filesToDo.Remove(p)
106
124
} else {
107
-
filesToDo[f] = struct{}{}
125
+
filesToDo.Insert(p)
108
126
}
109
127
}
110
128
111
-
if len(filesToDo) == 0 {
129
+
if filesToDo.IsEmpty() {
112
130
return filesDone, nil
113
131
}
114
132
···
116
134
defer cancel()
117
135
118
136
pathSpec := "."
119
-
if parent != "" {
120
-
pathSpec = parent
137
+
if parent.dir != "" {
138
+
pathSpec = parent.dir
139
+
}
140
+
if filesToDo.Len() == 1 {
141
+
// this is an optimization for the scenario where we want to calculate
142
+
// the last commit for just one path, we can directly set the pathspec to that path
143
+
for s := range filesToDo.All() {
144
+
pathSpec = s
145
+
}
121
146
}
122
-
output, err := g.streamingGitLog(ctx, "--pretty=format:%H,%ad,%s", "--date=iso", "--name-only", "--", pathSpec)
147
+
148
+
output, err := g.streamingGitLog(ctx, "--pretty=format:%H,%ad,%s", "--date=unix", "--name-only", "--", pathSpec)
123
149
if err != nil {
124
150
return nil, err
125
151
}
126
152
defer output.Close() // Ensure the git process is properly cleaned up
127
153
128
154
reader := bufio.NewReader(output)
129
-
var current commit
155
+
current := newCommit()
130
156
for {
131
157
line, err := reader.ReadString('\n')
132
158
if err != nil && err != io.EOF {
···
137
163
if line == "" {
138
164
if !current.hash.IsZero() {
139
165
// we have a fully parsed commit
140
-
for _, f := range current.files {
141
-
if _, ok := filesToDo[f]; ok {
166
+
for f := range current.files.All() {
167
+
if filesToDo.Contains(f) {
142
168
filesDone[f] = current
143
-
delete(filesToDo, f)
169
+
filesToDo.Remove(f)
144
170
commitCache.Set(cacheKey(g, f), current, 0)
145
171
}
146
172
}
147
173
148
-
if len(filesToDo) == 0 {
149
-
cancel()
174
+
if filesToDo.IsEmpty() {
150
175
break
151
176
}
152
-
current = commit{}
177
+
current = newCommit()
153
178
}
154
179
} else if current.hash.IsZero() {
155
180
parts := strings.SplitN(line, ",", 3)
156
181
if len(parts) == 3 {
157
182
current.hash = plumbing.NewHash(parts[0])
158
-
current.when, _ = time.Parse("2006-01-02 15:04:05 -0700", parts[1])
183
+
epochTime, _ := strconv.ParseInt(parts[1], 10, 64)
184
+
current.when = time.Unix(epochTime, 0)
159
185
current.message = parts[2]
160
186
}
161
187
} else {
162
188
// all ancestors along this path should also be included
163
189
file := path.Clean(line)
164
-
ancestors := ancestors(file)
165
-
current.files = append(current.files, file)
166
-
current.files = append(current.files, ancestors...)
190
+
current.files.Insert(file)
191
+
for _, a := range ancestors(file) {
192
+
current.files.Insert(a)
193
+
}
167
194
}
168
195
169
196
if err == io.EOF {
···
174
201
return filesDone, nil
175
202
}
176
203
177
-
func ancestors(p string) []string {
178
-
var ancestors []string
179
-
180
-
for {
181
-
p = path.Dir(p)
182
-
if p == "." || p == "/" {
183
-
break
184
-
}
185
-
ancestors = append(ancestors, p)
204
+
// LastCommitFile returns the last commit information for a specific file path
205
+
func (g *GitRepo) LastCommitFile(ctx context.Context, filePath string) (*types.LastCommitInfo, error) {
206
+
parent, child := path.Split(filePath)
207
+
parent = path.Clean(parent)
208
+
if parent == "." {
209
+
parent = ""
186
210
}
187
-
return ancestors
188
-
}
189
211
190
-
// GetLastCommitForPath returns the last commit information for a specific file path
191
-
func (g *GitRepo) GetLastCommitForPath(ctx context.Context, filePath string) (*types.LastCommitInfo, error) {
192
-
c, err := g.r.CommitObject(g.h)
193
-
if err != nil {
194
-
return nil, fmt.Errorf("commit object: %w", err)
212
+
lastCommitDir := lastCommitDir{
213
+
dir: parent,
214
+
entries: []string{child},
195
215
}
196
216
197
-
tree, err := c.Tree()
217
+
times, err := g.lastCommitDirIn(ctx, lastCommitDir, 2*time.Second)
198
218
if err != nil {
199
-
return nil, fmt.Errorf("file tree: %w", err)
200
-
}
201
-
202
-
// parent directory for calculateCommitTime
203
-
parent := path.Dir(filePath)
204
-
if parent == "." {
205
-
parent = ""
219
+
return nil, fmt.Errorf("calculate commit time: %w", err)
206
220
}
207
221
208
-
times, err := g.calculateCommitTimeIn(ctx, tree, parent, 2*time.Second)
209
-
if err != nil {
210
-
return nil, fmt.Errorf("calculate commit time: %w", err)
222
+
// extract the only element of the map, the commit info of the current path
223
+
var commitInfo *commit
224
+
for _, c := range times {
225
+
commitInfo = &c
211
226
}
212
227
213
-
commitInfo, ok := times[filePath]
214
-
if !ok {
228
+
if commitInfo == nil {
215
229
return nil, fmt.Errorf("no commit found for path: %s", filePath)
216
230
}
217
231
···
221
235
When: commitInfo.when,
222
236
}, nil
223
237
}
238
+
239
+
func ancestors(p string) []string {
240
+
var ancestors []string
241
+
242
+
for {
243
+
p = path.Dir(p)
244
+
if p == "." || p == "/" {
245
+
break
246
+
}
247
+
ancestors = append(ancestors, p)
248
+
}
249
+
return ancestors
250
+
}