Commit `0d06714a92`

0d06714a922332eca48f3ca81fe3c721af687115

parent: 8375b863f5

Verified · cmc

cmc <hello@cleberg.net> · 2026-09-26 18:48 UTC

Keep recently modified stale derivative dirs during prune

A request holding an older library snapshot may still be writing into a
stale version directory. Skip directories modified within the last five
minutes; a later prune removes them.

Closes #1

Layout: unified · split

internal/render/render.go +8

		@@ -8,6 +8,7 @@ import (
8	8	"path/filepath"
9	9	"slices"
10	10	"strconv"
	11	"time"
11	12
12	13	"golang.org/x/sync/singleflight"
13	14
		@@ -84,6 +85,10 @@ func (r Renderer) generate(it library.Item, w int, dst string) error {
84	85	return os.Rename(tmp.Name(), dst)
85	86	}
86	87
	88	// pruneGrace keeps stale directories modified this recently, since a request
	89	// holding an older library snapshot may still be writing into them.
	90	const pruneGrace = 5 * time.Minute
	91
87	92	// Prune removes derivative directories for items no longer in lib or whose source changed.
88	93	func (r Renderer) Prune(lib library.Library) error {
89	94	keep := map[string]bool{}
		@@ -99,6 +104,9 @@ func (r Renderer) Prune(lib library.Library) error {
99	104	var firstErr error
100	105	for _, v := range versions {
101	106	if !keep[v] {
	107	if fi, err := os.Stat(v); err == nil && time.Since(fi.ModTime()) < pruneGrace {
	108	continue
	109	}
102	110	if err := os.RemoveAll(v); err != nil {
103	111	log.Printf("prune %s: %v", v, err)
104	112	if firstErr == nil {

internal/render/render_test.go +19

		@@ -151,6 +151,10 @@ func TestPrune(t *testing.T) {
151	151	t.Fatal(err)
152	152	}
153	153	}
	154	past := time.Now().Add(-2 * pruneGrace)
	155	for _, it := range []*library.Item{cur, old, gone} {
	156	os.Chtimes(filepath.Dir(r.Path(it, 480)), past, past)
	157	}
154	158	lib := &library.Library{Albums: []library.Album{{Slug: "tokyo", Items: []library.Item{cur}}}}
155	159	if err := r.Prune(lib); err != nil {
156	160	t.Fatal(err)
		@@ -164,3 +168,18 @@ func TestPrune(t *testing.T) {
164	168	}
165	169	}
166	170	}
	171
	172	func TestPruneKeepsRecentlyModifiedStaleDir(t *testing.T) {
	173	f := &fakeFormat{}
	174	r := New(t.TempDir(), 1)
	175	old := item(f)
	176	if _, err := r.Get(old, 480); err != nil {
	177	t.Fatal(err)
	178	}
	179	if err := r.Prune(&library.Library{}); err != nil {
	180	t.Fatal(err)
	181	}
	182	if _, err := os.Stat(r.Path(old, 480)); err != nil {
	183	t.Fatalf("recently written stale dir removed: %v", err)
	184	}
	185	}

Commit 0d06714a92

Commit `0d06714a92`