| 1 | package release |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "errors" |
| 6 | "fmt" |
| 7 | "io/fs" |
| 8 | "reflect" |
| 9 | "sort" |
| 10 | "sync" |
| 11 | "testing" |
| 12 | "time" |
| 13 | ) |
| 14 | |
| 15 | // condCounter wraps a DirStore and records the etag every GetIfChanged call |
| 16 | // carried, so a test can see that the second poll was conditional. |
| 17 | type condCounter struct { |
| 18 | *DirStore |
| 19 | mu sync.Mutex |
| 20 | etags []string |
| 21 | getErr error // when set, GetIfChanged fails with it |
| 22 | } |
| 23 | |
| 24 | func (c *condCounter) GetIfChanged(ctx context.Context, key, etag string) ([]byte, string, bool, error) { |
| 25 | c.mu.Lock() |
| 26 | c.etags = append(c.etags, etag) |
| 27 | err := c.getErr |
| 28 | c.mu.Unlock() |
| 29 | if err != nil { |
| 30 | return nil, "", false, err |
| 31 | } |
| 32 | return c.DirStore.GetIfChanged(ctx, key, etag) |
| 33 | } |
| 34 | |
| 35 | func (c *condCounter) setErr(err error) { |
| 36 | c.mu.Lock() |
| 37 | c.getErr = err |
| 38 | c.mu.Unlock() |
| 39 | } |
| 40 | |
| 41 | func (c *condCounter) seen() []string { |
| 42 | c.mu.Lock() |
| 43 | defer c.mu.Unlock() |
| 44 | return append([]string(nil), c.etags...) |
| 45 | } |
| 46 | |
| 47 | func writeScoped(t *testing.T, s Store, keys ...string) { |
| 48 | t.Helper() |
| 49 | for _, k := range keys { |
| 50 | if _, err := s.Put(context.Background(), k, []byte("x"), ""); err != nil { |
| 51 | t.Fatal(err) |
| 52 | } |
| 53 | } |
| 54 | } |
| 55 | |
| 56 | func TestChangeWatchFirstPollReportsAll(t *testing.T) { |
| 57 | t.Parallel() |
| 58 | d := indexedDirStore(t) |
| 59 | writeScoped(t, d, "apps/bab/shop/instances/h.json", "accounts/acme/members.json") |
| 60 | w := NewChangeWatch(d) |
| 61 | if w.Usable() { |
| 62 | t.Fatal("a watch that has not polled is usable") |
| 63 | } |
| 64 | if _, ok := w.Gen("apps/bab/shop"); ok { |
| 65 | t.Fatal("Gen ok before the first poll") |
| 66 | } |
| 67 | moved, err := w.Poll(context.Background()) |
| 68 | if err != nil { |
| 69 | t.Fatal(err) |
| 70 | } |
| 71 | want := []string{"accounts/acme", "apps/bab/shop"} |
| 72 | if !reflect.DeepEqual(moved, want) { |
| 73 | t.Fatalf("moved = %v, want %v", moved, want) |
| 74 | } |
| 75 | if !w.Usable() { |
| 76 | t.Fatal("not usable after a good poll") |
| 77 | } |
| 78 | if g, ok := w.Gen("apps/bab/shop"); !ok || g != 1 { |
| 79 | t.Fatalf("Gen = %d, %v; want 1, true", g, ok) |
| 80 | } |
| 81 | if g, ok := w.Gen("apps/bab/other"); !ok || g != 0 { |
| 82 | t.Fatalf("Gen of an unlisted scope = %d, %v; want 0, true", g, ok) |
| 83 | } |
| 84 | } |
| 85 | |
| 86 | func TestChangeWatchUnchangedIs304(t *testing.T) { |
| 87 | t.Parallel() |
| 88 | c := &condCounter{DirStore: indexedDirStore(t)} |
| 89 | writeScoped(t, c.DirStore, "apps/bab/shop/instances/h.json") |
| 90 | w := NewChangeWatch(c) |
| 91 | if _, err := w.Poll(context.Background()); err != nil { |
| 92 | t.Fatal(err) |
| 93 | } |
| 94 | moved, err := w.Poll(context.Background()) |
| 95 | if err != nil || moved != nil { |
| 96 | t.Fatalf("second poll = %v, %v; want nil, nil", moved, err) |
| 97 | } |
| 98 | seen := c.seen() |
| 99 | if len(seen) != 2 || seen[0] != "" || seen[1] == "" { |
| 100 | t.Fatalf("etags sent = %q; want an empty one, then the index's", seen) |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | func TestChangeWatchReportsOnlyMoved(t *testing.T) { |
| 105 | t.Parallel() |
| 106 | d := indexedDirStore(t) |
| 107 | writeScoped(t, d, "apps/bab/shop/instances/h.json", "accounts/acme/members.json") |
| 108 | w := NewChangeWatch(d) |
| 109 | if _, err := w.Poll(context.Background()); err != nil { |
| 110 | t.Fatal(err) |
| 111 | } |
| 112 | writeScoped(t, d, "apps/bab/shop/instances/i.json", "control/certs/example.com.json") |
| 113 | moved, err := w.Poll(context.Background()) |
| 114 | if err != nil { |
| 115 | t.Fatal(err) |
| 116 | } |
| 117 | want := []string{"apps/bab/shop", "control/certs"} |
| 118 | if !reflect.DeepEqual(moved, want) { |
| 119 | t.Fatalf("moved = %v, want %v", moved, want) |
| 120 | } |
| 121 | if g, _ := w.Gen("apps/bab/shop"); g != 2 { |
| 122 | t.Fatalf("Gen = %d, want 2", g) |
| 123 | } |
| 124 | } |
| 125 | |
| 126 | func TestChangeWatchAbsentIndexIsUsableEmpty(t *testing.T) { |
| 127 | t.Parallel() |
| 128 | d := indexedDirStore(t) |
| 129 | w := NewChangeWatch(d) |
| 130 | moved, err := w.Poll(context.Background()) |
| 131 | if err != nil || len(moved) != 0 { |
| 132 | t.Fatalf("poll = %v, %v; want nothing", moved, err) |
| 133 | } |
| 134 | if !w.Usable() { |
| 135 | t.Fatal("an absent index is the pre-first-bump state and must be usable") |
| 136 | } |
| 137 | if obs, ok := w.Observed(); !ok || len(obs) != 0 { |
| 138 | t.Fatalf("Observed = %v, %v; want empty, true", obs, ok) |
| 139 | } |
| 140 | // The first write then shows up as an appearance. |
| 141 | writeScoped(t, d, "apps/bab/shop/instances/h.json") |
| 142 | moved, err = w.Poll(context.Background()) |
| 143 | if err != nil || !reflect.DeepEqual(moved, []string{"apps/bab/shop"}) { |
| 144 | t.Fatalf("poll after first write = %v, %v", moved, err) |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | func TestChangeWatchDeniedIsUnusable(t *testing.T) { |
| 149 | t.Parallel() |
| 150 | c := &condCounter{DirStore: indexedDirStore(t)} |
| 151 | writeScoped(t, c.DirStore, "apps/bab/shop/instances/h.json") |
| 152 | c.setErr(fmt.Errorf("get %s: %w", ChangeIndexKey, fs.ErrPermission)) |
| 153 | w := NewChangeWatch(c) |
| 154 | moved, err := w.Poll(context.Background()) |
| 155 | if !errors.Is(err, fs.ErrPermission) || moved != nil { |
| 156 | t.Fatalf("poll = %v, %v; want the access error", moved, err) |
| 157 | } |
| 158 | if w.Usable() { |
| 159 | t.Fatal("usable after a denied read") |
| 160 | } |
| 161 | if _, ok := w.Gen("apps/bab/shop"); ok { |
| 162 | t.Fatal("Gen ok while unusable") |
| 163 | } |
| 164 | if _, ok := w.Observed(); ok { |
| 165 | t.Fatal("Observed ok while unusable") |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | func TestChangeWatchUsableThenErrorThenRecovers(t *testing.T) { |
| 170 | t.Parallel() |
| 171 | c := &condCounter{DirStore: indexedDirStore(t)} |
| 172 | writeScoped(t, c.DirStore, "apps/bab/shop/instances/h.json", "accounts/acme/members.json") |
| 173 | w := NewChangeWatch(c) |
| 174 | if _, err := w.Poll(context.Background()); err != nil { |
| 175 | t.Fatal(err) |
| 176 | } |
| 177 | c.setErr(errors.New("network down")) |
| 178 | writeScoped(t, c.DirStore, "apps/bab/shop/instances/i.json") |
| 179 | if _, err := w.Poll(context.Background()); err == nil { |
| 180 | t.Fatal("poll succeeded through an error") |
| 181 | } |
| 182 | if w.Usable() { |
| 183 | t.Fatal("still usable after an error") |
| 184 | } |
| 185 | c.setErr(nil) |
| 186 | moved, err := w.Poll(context.Background()) |
| 187 | if err != nil { |
| 188 | t.Fatal(err) |
| 189 | } |
| 190 | if !reflect.DeepEqual(moved, []string{"apps/bab/shop"}) { |
| 191 | t.Fatalf("moved = %v; want the scope that rose while unusable", moved) |
| 192 | } |
| 193 | if !w.Usable() { |
| 194 | t.Fatal("not usable after recovering") |
| 195 | } |
| 196 | // An unchanged index after an error recovers without a spurious move. |
| 197 | c.setErr(errors.New("blip")) |
| 198 | _, _ = w.Poll(context.Background()) |
| 199 | c.setErr(nil) |
| 200 | moved, err = w.Poll(context.Background()) |
| 201 | if err != nil || moved != nil || !w.Usable() { |
| 202 | t.Fatalf("recovery on an unchanged index = %v, %v, usable %v", moved, err, w.Usable()) |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | func TestChangeWatchUnknownSchemaIsUnusable(t *testing.T) { |
| 207 | t.Parallel() |
| 208 | d := NewDirStore(t.TempDir()) |
| 209 | if _, err := d.Put(context.Background(), ChangeIndexKey, []byte(`{"schema":2,"entries":{"apps/a/b":1}}`), ""); err != nil { |
| 210 | t.Fatal(err) |
| 211 | } |
| 212 | w := NewChangeWatch(d) |
| 213 | _, err := w.Poll(context.Background()) |
| 214 | if !errors.Is(err, ErrChangeIndexSchema) { |
| 215 | t.Fatalf("err = %v, want ErrChangeIndexSchema", err) |
| 216 | } |
| 217 | if w.Usable() { |
| 218 | t.Fatal("usable on an unknown schema") |
| 219 | } |
| 220 | // A malformed body is unknown too. |
| 221 | _, etag, _ := d.Get(context.Background(), ChangeIndexKey) |
| 222 | if _, err := d.Put(context.Background(), ChangeIndexKey, []byte(`not json`), etag); err != nil { |
| 223 | t.Fatal(err) |
| 224 | } |
| 225 | if _, err := w.Poll(context.Background()); err == nil || w.Usable() { |
| 226 | t.Fatalf("malformed index: err %v, usable %v", err, w.Usable()) |
| 227 | } |
| 228 | } |
| 229 | |
| 230 | func TestChangeWatchWithoutExtensionIsUnusable(t *testing.T) { |
| 231 | t.Parallel() |
| 232 | w := NewChangeWatch(bareStore{NewDirStore(t.TempDir())}) |
| 233 | _, err := w.Poll(context.Background()) |
| 234 | if !errors.Is(err, errors.ErrUnsupported) { |
| 235 | t.Fatalf("err = %v, want ErrUnsupported", err) |
| 236 | } |
| 237 | if w.Usable() { |
| 238 | t.Fatal("usable without ConditionalGetter") |
| 239 | } |
| 240 | // The prefix wrapper over such a store answers ErrUnsupported itself. |
| 241 | w = NewChangeWatch(NewPrefixStore(bareStore{NewDirStore(t.TempDir())}, "base/")) |
| 242 | if _, err := w.Poll(context.Background()); err == nil || w.Usable() { |
| 243 | t.Fatalf("prefixed bare store: err %v, usable %v", err, w.Usable()) |
| 244 | } |
| 245 | } |
| 246 | |
| 247 | func TestChangeWatchObservedIsACopy(t *testing.T) { |
| 248 | t.Parallel() |
| 249 | d := indexedDirStore(t) |
| 250 | writeScoped(t, d, "apps/bab/shop/instances/h.json") |
| 251 | w := NewChangeWatch(d) |
| 252 | if _, err := w.Poll(context.Background()); err != nil { |
| 253 | t.Fatal(err) |
| 254 | } |
| 255 | obs, _ := w.Observed() |
| 256 | obs["apps/bab/shop"] = 99 |
| 257 | delete(obs, "nothing") |
| 258 | if g, _ := w.Gen("apps/bab/shop"); g != 1 { |
| 259 | t.Fatalf("mutating Observed changed the watch: Gen = %d", g) |
| 260 | } |
| 261 | } |
| 262 | |
| 263 | func TestChangeWatchConcurrentPolls(t *testing.T) { |
| 264 | t.Parallel() |
| 265 | d := indexedDirStore(t) |
| 266 | writeScoped(t, d, "apps/bab/shop/instances/h.json") |
| 267 | w := NewChangeWatch(d) |
| 268 | var wg sync.WaitGroup |
| 269 | var mu sync.Mutex |
| 270 | var all []string |
| 271 | for range 8 { |
| 272 | wg.Add(1) |
| 273 | go func() { |
| 274 | defer wg.Done() |
| 275 | moved, err := w.Poll(context.Background()) |
| 276 | if err != nil { |
| 277 | t.Error(err) |
| 278 | } |
| 279 | w.Gen("apps/bab/shop") |
| 280 | w.Observed() |
| 281 | mu.Lock() |
| 282 | all = append(all, moved...) |
| 283 | mu.Unlock() |
| 284 | }() |
| 285 | } |
| 286 | wg.Wait() |
| 287 | sort.Strings(all) |
| 288 | if !reflect.DeepEqual(all, []string{"apps/bab/shop"}) { |
| 289 | t.Fatalf("scope reported %v across racing polls; want once", all) |
| 290 | } |
| 291 | } |
| 292 | |
| 293 | func TestReadGateDue(t *testing.T) { |
| 294 | t.Parallel() |
| 295 | const maxAge = 30 * time.Minute |
| 296 | t0 := time.Date(2026, 10, 22, 12, 0, 0, 0, time.UTC) |
| 297 | const scope = "apps/bab/shop" |
| 298 | ctx := context.Background() |
| 299 | |
| 300 | usableWatch := func(t *testing.T) (*ChangeWatch, *DirStore) { |
| 301 | d := indexedDirStore(t) |
| 302 | writeScoped(t, d, "apps/bab/shop/instances/h.json") |
| 303 | w := NewChangeWatch(d) |
| 304 | if _, err := w.Poll(ctx); err != nil { |
| 305 | t.Fatal(err) |
| 306 | } |
| 307 | return w, d |
| 308 | } |
| 309 | |
| 310 | tests := []struct { |
| 311 | name string |
| 312 | run func(t *testing.T) bool // returns Due's answer |
| 313 | want bool |
| 314 | }{ |
| 315 | {"nil watch is due", func(t *testing.T) bool { |
| 316 | _, due := NewReadGate(nil, maxAge).Due(scope, t0) |
| 317 | return due |
| 318 | }, true}, |
| 319 | {"unusable watch is due", func(t *testing.T) bool { |
| 320 | g := NewReadGate(NewChangeWatch(NewDirStore(t.TempDir())), maxAge) |
| 321 | _, due := g.Due(scope, t0) |
| 322 | return due |
| 323 | }, true}, |
| 324 | {"never marked is due", func(t *testing.T) bool { |
| 325 | w, _ := usableWatch(t) |
| 326 | _, due := NewReadGate(w, maxAge).Due(scope, t0) |
| 327 | return due |
| 328 | }, true}, |
| 329 | {"marked ok, same gen, within age is not due", func(t *testing.T) bool { |
| 330 | w, _ := usableWatch(t) |
| 331 | g := NewReadGate(w, maxAge) |
| 332 | gen, _ := g.Due(scope, t0) |
| 333 | g.Mark(scope, gen, t0, true) |
| 334 | _, due := g.Due(scope, t0.Add(maxAge-time.Second)) |
| 335 | return due |
| 336 | }, false}, |
| 337 | {"generation moved is due", func(t *testing.T) bool { |
| 338 | w, d := usableWatch(t) |
| 339 | g := NewReadGate(w, maxAge) |
| 340 | gen, _ := g.Due(scope, t0) |
| 341 | g.Mark(scope, gen, t0, true) |
| 342 | writeScoped(t, d, "apps/bab/shop/instances/i.json") |
| 343 | if _, err := w.Poll(ctx); err != nil { |
| 344 | t.Fatal(err) |
| 345 | } |
| 346 | _, due := g.Due(scope, t0.Add(time.Second)) |
| 347 | return due |
| 348 | }, true}, |
| 349 | {"other scope moving is not due", func(t *testing.T) bool { |
| 350 | w, d := usableWatch(t) |
| 351 | g := NewReadGate(w, maxAge) |
| 352 | gen, _ := g.Due(scope, t0) |
| 353 | g.Mark(scope, gen, t0, true) |
| 354 | writeScoped(t, d, "accounts/acme/members.json") |
| 355 | if _, err := w.Poll(ctx); err != nil { |
| 356 | t.Fatal(err) |
| 357 | } |
| 358 | _, due := g.Due(scope, t0.Add(time.Second)) |
| 359 | return due |
| 360 | }, false}, |
| 361 | {"age at maxAge is due", func(t *testing.T) bool { |
| 362 | w, _ := usableWatch(t) |
| 363 | g := NewReadGate(w, maxAge) |
| 364 | gen, _ := g.Due(scope, t0) |
| 365 | g.Mark(scope, gen, t0, true) |
| 366 | _, due := g.Due(scope, t0.Add(maxAge)) |
| 367 | return due |
| 368 | }, true}, |
| 369 | {"last mark failed is due", func(t *testing.T) bool { |
| 370 | w, _ := usableWatch(t) |
| 371 | g := NewReadGate(w, maxAge) |
| 372 | gen, _ := g.Due(scope, t0) |
| 373 | g.Mark(scope, gen, t0, false) |
| 374 | _, due := g.Due(scope, t0.Add(time.Second)) |
| 375 | return due |
| 376 | }, true}, |
| 377 | {"a failed mark after a good one is due", func(t *testing.T) bool { |
| 378 | w, _ := usableWatch(t) |
| 379 | g := NewReadGate(w, maxAge) |
| 380 | gen, _ := g.Due(scope, t0) |
| 381 | g.Mark(scope, gen, t0, true) |
| 382 | g.Mark(scope, gen, t0.Add(time.Minute), false) |
| 383 | _, due := g.Due(scope, t0.Add(2*time.Minute)) |
| 384 | return due |
| 385 | }, true}, |
| 386 | {"watch going unusable makes a marked scope due", func(t *testing.T) bool { |
| 387 | c := &condCounter{DirStore: indexedDirStore(t)} |
| 388 | writeScoped(t, c.DirStore, "apps/bab/shop/instances/h.json") |
| 389 | w := NewChangeWatch(c) |
| 390 | if _, err := w.Poll(ctx); err != nil { |
| 391 | t.Fatal(err) |
| 392 | } |
| 393 | g := NewReadGate(w, maxAge) |
| 394 | gen, _ := g.Due(scope, t0) |
| 395 | g.Mark(scope, gen, t0, true) |
| 396 | c.setErr(errors.New("down")) |
| 397 | _, _ = w.Poll(ctx) |
| 398 | _, due := g.Due(scope, t0.Add(time.Second)) |
| 399 | return due |
| 400 | }, true}, |
| 401 | } |
| 402 | for _, tc := range tests { |
| 403 | t.Run(tc.name, func(t *testing.T) { |
| 404 | t.Parallel() |
| 405 | if got := tc.run(t); got != tc.want { |
| 406 | t.Fatalf("due = %v, want %v", got, tc.want) |
| 407 | } |
| 408 | }) |
| 409 | } |
| 410 | } |
| 411 | |
| 412 | func TestReadGateCapturedGenSurvivesRaceWithPoll(t *testing.T) { |
| 413 | t.Parallel() |
| 414 | ctx := context.Background() |
| 415 | d := indexedDirStore(t) |
| 416 | writeScoped(t, d, "apps/bab/shop/instances/h.json") |
| 417 | w := NewChangeWatch(d) |
| 418 | if _, err := w.Poll(ctx); err != nil { |
| 419 | t.Fatal(err) |
| 420 | } |
| 421 | g := NewReadGate(w, time.Hour) |
| 422 | t0 := time.Now() |
| 423 | gen, due := g.Due("apps/bab/shop", t0) |
| 424 | if !due { |
| 425 | t.Fatal("never-marked scope not due") |
| 426 | } |
| 427 | // A write lands and is polled while the read is in flight. |
| 428 | writeScoped(t, d, "apps/bab/shop/instances/i.json") |
| 429 | if _, err := w.Poll(ctx); err != nil { |
| 430 | t.Fatal(err) |
| 431 | } |
| 432 | g.Mark("apps/bab/shop", gen, t0, true) // the generation captured BEFORE the read |
| 433 | if _, due := g.Due("apps/bab/shop", t0); !due { |
| 434 | t.Fatal("a mark of the pre-read generation hid a write that landed during the read") |
| 435 | } |
| 436 | } |
| 437 | |
| 438 | // blockingCond is a DirStore whose GetIfChanged, once armed, parks until |
| 439 | // released: a hung index GET holding the watch's poll lock. |
| 440 | type blockingCond struct { |
| 441 | *DirStore |
| 442 | mu sync.Mutex |
| 443 | block chan struct{} // nil = no blocking |
| 444 | entered chan struct{} |
| 445 | } |
| 446 | |
| 447 | func (b *blockingCond) arm() (entered, release chan struct{}) { |
| 448 | b.mu.Lock() |
| 449 | defer b.mu.Unlock() |
| 450 | b.block, b.entered = make(chan struct{}), make(chan struct{}, 1) |
| 451 | return b.entered, b.block |
| 452 | } |
| 453 | |
| 454 | func (b *blockingCond) GetIfChanged(ctx context.Context, key, etag string) ([]byte, string, bool, error) { |
| 455 | b.mu.Lock() |
| 456 | block, entered := b.block, b.entered |
| 457 | b.mu.Unlock() |
| 458 | if block != nil { |
| 459 | entered <- struct{}{} |
| 460 | <-block |
| 461 | } |
| 462 | return b.DirStore.GetIfChanged(ctx, key, etag) |
| 463 | } |
| 464 | |
| 465 | // A Poll waiting behind a stuck one gives up when its context ends. The |
| 466 | // give-up is a failed poll like any other: the watch is unknown until the |
| 467 | // next good one (a frozen observation must never vouch for a gated read), |
| 468 | // but it keeps its ETag and entries, so that next poll is a 304 that |
| 469 | // reports nothing moved. |
| 470 | func TestChangeWatchPollLockWaitHonoursContext(t *testing.T) { |
| 471 | t.Parallel() |
| 472 | d := indexedDirStore(t) |
| 473 | writeScoped(t, d, "apps/bab/shop/instances/h.json") |
| 474 | b := &blockingCond{DirStore: d} |
| 475 | w := NewChangeWatch(b) |
| 476 | if _, err := w.Poll(context.Background()); err != nil { |
| 477 | t.Fatal(err) |
| 478 | } |
| 479 | gen, _ := w.Gen("apps/bab/shop") |
| 480 | |
| 481 | entered, release := b.arm() |
| 482 | stuck := make(chan error, 1) |
| 483 | go func() { |
| 484 | _, err := w.Poll(context.Background()) |
| 485 | stuck <- err |
| 486 | }() |
| 487 | <-entered |
| 488 | |
| 489 | ctx, cancel := context.WithTimeout(context.Background(), 50*time.Millisecond) |
| 490 | defer cancel() |
| 491 | done := make(chan error, 1) |
| 492 | go func() { |
| 493 | _, err := w.Poll(ctx) |
| 494 | done <- err |
| 495 | }() |
| 496 | select { |
| 497 | case err := <-done: |
| 498 | if !errors.Is(err, context.DeadlineExceeded) { |
| 499 | t.Fatalf("waiting Poll returned %v, want the context's error", err) |
| 500 | } |
| 501 | case <-time.After(5 * time.Second): |
| 502 | close(release) |
| 503 | t.Fatal("a Poll waiting behind a stuck one ignored its context") |
| 504 | } |
| 505 | if w.Usable() { |
| 506 | t.Fatal("a give-up on the lock left the watch usable: its observation is frozen") |
| 507 | } |
| 508 | if _, ok := w.Gen("apps/bab/shop"); ok { |
| 509 | t.Fatal("Gen vouched for a scope after a give-up") |
| 510 | } |
| 511 | if _, ok := w.Observed(); ok { |
| 512 | t.Fatal("Observed vouched after a give-up") |
| 513 | } |
| 514 | close(release) |
| 515 | if err := <-stuck; err != nil { |
| 516 | t.Fatalf("the stuck Poll, released: %v", err) |
| 517 | } |
| 518 | if g, ok := w.Gen("apps/bab/shop"); !ok || g != gen { |
| 519 | t.Fatalf("Gen after the stuck poll answered = %d, %v; want %d, true", g, ok, gen) |
| 520 | } |
| 521 | } |
| 522 | |
| 523 | // A Poll whose context has already ended reads nothing, and is a failed |
| 524 | // poll: the watch is unknown until the next good one, which is a 304 |
| 525 | // because the watch kept its ETag. |
| 526 | func TestChangeWatchCancelledPollIsUnknownThenA304(t *testing.T) { |
| 527 | t.Parallel() |
| 528 | d := indexedDirStore(t) |
| 529 | writeScoped(t, d, "apps/bab/shop/instances/h.json") |
| 530 | c := &condCounter{DirStore: d} |
| 531 | w := NewChangeWatch(c) |
| 532 | if _, err := w.Poll(context.Background()); err != nil { |
| 533 | t.Fatal(err) |
| 534 | } |
| 535 | ctx, cancel := context.WithCancel(context.Background()) |
| 536 | cancel() |
| 537 | if _, err := w.Poll(ctx); !errors.Is(err, context.Canceled) { |
| 538 | t.Fatalf("a cancelled Poll returned %v", err) |
| 539 | } |
| 540 | if w.Usable() { |
| 541 | t.Fatal("a cancelled Poll left the watch usable") |
| 542 | } |
| 543 | moved, err := w.Poll(context.Background()) |
| 544 | if err != nil || moved != nil || !w.Usable() { |
| 545 | t.Fatalf("recovery = %v, %v, usable %v; want nothing moved and usable", moved, err, w.Usable()) |
| 546 | } |
| 547 | seen := c.seen() |
| 548 | if last := seen[len(seen)-1]; last == "" { |
| 549 | t.Fatalf("the recovery poll was unconditional (etags %q): the give-up dropped the ETag", seen) |
| 550 | } |
| 551 | } |
| 552 | |
amadan