services/keepproxy/keepproxy_test.go

   1 package main
   2
   3 import (
   4         "bytes"
   5         "crypto/md5"
   6         "errors"
   7         "fmt"
   8         "io/ioutil"
   9         "log"
  10         "net/http"
  11         "net/http/httptest"
  12         "os"
  13         "strings"
  14         "testing"
  15         "time"
  16
  17         "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
  18         "git.curoverse.com/arvados.git/sdk/go/arvadostest"
  19         "git.curoverse.com/arvados.git/sdk/go/keepclient"
  20
  21         . "gopkg.in/check.v1"
  22 )
  23
  24 // Gocheck boilerplate
  25 func Test(t *testing.T) {
  26         TestingT(t)
  27 }
  28
  29 // Gocheck boilerplate
  30 var _ = Suite(&ServerRequiredSuite{})
  31
  32 // Tests that require the Keep server running
  33 type ServerRequiredSuite struct{}
  34
  35 // Gocheck boilerplate
  36 var _ = Suite(&NoKeepServerSuite{})
  37
  38 // Test with no keepserver to simulate errors
  39 type NoKeepServerSuite struct{}
  40
  41 var TestProxyUUID = "zzzzz-bi6l4-lrixqc4fxofbmzz"
  42
  43 // Wait (up to 1 second) for keepproxy to listen on a port. This
  44 // avoids a race condition where we hit a "connection refused" error
  45 // because we start testing the proxy too soon.
  46 func waitForListener() {
  47         const (
  48                 ms = 5
  49         )
  50         for i := 0; listener == nil && i < 10000; i += ms {
  51                 time.Sleep(ms * time.Millisecond)
  52         }
  53         if listener == nil {
  54                 log.Fatalf("Timed out waiting for listener to start")
  55         }
  56 }
  57
  58 func closeListener() {
  59         if listener != nil {
  60                 listener.Close()
  61         }
  62 }
  63
  64 func (s *ServerRequiredSuite) SetUpSuite(c *C) {
  65         arvadostest.StartAPI()
  66         arvadostest.StartKeep(2, false)
  67 }
  68
  69 func (s *ServerRequiredSuite) SetUpTest(c *C) {
  70         arvadostest.ResetEnv()
  71 }
  72
  73 func (s *ServerRequiredSuite) TearDownSuite(c *C) {
  74         arvadostest.StopKeep(2)
  75         arvadostest.StopAPI()
  76 }
  77
  78 func (s *NoKeepServerSuite) SetUpSuite(c *C) {
  79         arvadostest.StartAPI()
  80         // We need API to have some keep services listed, but the
  81         // services themselves should be unresponsive.
  82         arvadostest.StartKeep(2, false)
  83         arvadostest.StopKeep(2)
  84 }
  85
  86 func (s *NoKeepServerSuite) SetUpTest(c *C) {
  87         arvadostest.ResetEnv()
  88 }
  89
  90 func (s *NoKeepServerSuite) TearDownSuite(c *C) {
  91         arvadostest.StopAPI()
  92 }
  93
  94 func runProxy(c *C, args []string, bogusClientToken bool) *keepclient.KeepClient {
  95         args = append([]string{"keepproxy"}, args...)
  96         os.Args = append(args, "-listen=:0")
  97         listener = nil
  98         go main()
  99         waitForListener()
 100
 101         arv, err := arvadosclient.MakeArvadosClient()
 102         c.Assert(err, Equals, nil)
 103         if bogusClientToken {
 104                 arv.ApiToken = "bogus-token"
 105         }
 106         kc := keepclient.New(arv)
 107         sr := map[string]string{
 108                 TestProxyUUID: "http://" + listener.Addr().String(),
 109         }
 110         kc.SetServiceRoots(sr, sr, sr)
 111         kc.Arvados.External = true
 112
 113         return kc
 114 }
 115
 116 func (s *ServerRequiredSuite) TestLoopDetection(c *C) {
 117         kc := runProxy(c, nil, false)
 118         defer closeListener()
 119
 120         sr := map[string]string{
 121                 TestProxyUUID: "http://" + listener.Addr().String(),
 122         }
 123         router.(*proxyHandler).KeepClient.SetServiceRoots(sr, sr, sr)
 124
 125         content := []byte("TestLoopDetection")
 126         _, _, err := kc.PutB(content)
 127         c.Check(err, ErrorMatches, `.*loop detected.*`)
 128
 129         hash := fmt.Sprintf("%x", md5.Sum(content))
 130         _, _, _, err = kc.Get(hash)
 131         c.Check(err, ErrorMatches, `.*loop detected.*`)
 132 }
 133
 134 func (s *ServerRequiredSuite) TestDesiredReplicas(c *C) {
 135         kc := runProxy(c, nil, false)
 136         defer closeListener()
 137
 138         content := []byte("TestDesiredReplicas")
 139         hash := fmt.Sprintf("%x", md5.Sum(content))
 140
 141         for _, kc.Want_replicas = range []int{0, 1, 2} {
 142                 locator, rep, err := kc.PutB(content)
 143                 c.Check(err, Equals, nil)
 144                 c.Check(rep, Equals, kc.Want_replicas)
 145                 if rep > 0 {
 146                         c.Check(locator, Matches, fmt.Sprintf(`^%s\+%d(\+.+)?$`, hash, len(content)))
 147                 }
 148         }
 149 }
 150
 151 func (s *ServerRequiredSuite) TestPutWrongContentLength(c *C) {
 152         kc := runProxy(c, nil, false)
 153         defer closeListener()
 154
 155         content := []byte("TestPutWrongContentLength")
 156         hash := fmt.Sprintf("%x", md5.Sum(content))
 157
 158         // If we use http.Client to send these requests to the network
 159         // server we just started, the Go http library automatically
 160         // fixes the invalid Content-Length header. In order to test
 161         // our server behavior, we have to call the handler directly
 162         // using an httptest.ResponseRecorder.
 163         rtr := MakeRESTRouter(true, true, kc)
 164
 165         type testcase struct {
 166                 sendLength   string
 167                 expectStatus int
 168         }
 169
 170         for _, t := range []testcase{
 171                 {"1", http.StatusBadRequest},
 172                 {"", http.StatusLengthRequired},
 173                 {"-1", http.StatusLengthRequired},
 174                 {"abcdef", http.StatusLengthRequired},
 175         } {
 176                 req, err := http.NewRequest("PUT",
 177                         fmt.Sprintf("http://%s/%s+%d", listener.Addr().String(), hash, len(content)),
 178                         bytes.NewReader(content))
 179                 c.Assert(err, IsNil)
 180                 req.Header.Set("Content-Length", t.sendLength)
 181                 req.Header.Set("Authorization", "OAuth2 4axaw8zxe0qm22wa6urpp5nskcne8z88cvbupv653y1njyi05h")
 182                 req.Header.Set("Content-Type", "application/octet-stream")
 183
 184                 resp := httptest.NewRecorder()
 185                 rtr.ServeHTTP(resp, req)
 186                 c.Check(resp.Code, Equals, t.expectStatus)
 187         }
 188 }
 189
 190 func (s *ServerRequiredSuite) TestPutAskGet(c *C) {
 191         kc := runProxy(c, nil, false)
 192         defer closeListener()
 193
 194         hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
 195         var hash2 string
 196
 197         {
 198                 _, _, err := kc.Ask(hash)
 199                 c.Check(err, Equals, keepclient.BlockNotFound)
 200                 log.Print("Finished Ask (expected BlockNotFound)")
 201         }
 202
 203         {
 204                 reader, _, _, err := kc.Get(hash)
 205                 c.Check(reader, Equals, nil)
 206                 c.Check(err, Equals, keepclient.BlockNotFound)
 207                 log.Print("Finished Get (expected BlockNotFound)")
 208         }
 209
 210         // Note in bug #5309 among other errors keepproxy would set
 211         // Content-Length incorrectly on the 404 BlockNotFound response, this
 212         // would result in a protocol violation that would prevent reuse of the
 213         // connection, which would manifest by the next attempt to use the
 214         // connection (in this case the PutB below) failing.  So to test for
 215         // that bug it's necessary to trigger an error response (such as
 216         // BlockNotFound) and then do something else with the same httpClient
 217         // connection.
 218
 219         {
 220                 var rep int
 221                 var err error
 222                 hash2, rep, err = kc.PutB([]byte("foo"))
 223                 c.Check(hash2, Matches, fmt.Sprintf(`^%s\+3(\+.+)?$`, hash))
 224                 c.Check(rep, Equals, 2)
 225                 c.Check(err, Equals, nil)
 226                 log.Print("Finished PutB (expected success)")
 227         }
 228
 229         {
 230                 blocklen, _, err := kc.Ask(hash2)
 231                 c.Assert(err, Equals, nil)
 232                 c.Check(blocklen, Equals, int64(3))
 233                 log.Print("Finished Ask (expected success)")
 234         }
 235
 236         {
 237                 reader, blocklen, _, err := kc.Get(hash2)
 238                 c.Assert(err, Equals, nil)
 239                 all, err := ioutil.ReadAll(reader)
 240                 c.Check(all, DeepEquals, []byte("foo"))
 241                 c.Check(blocklen, Equals, int64(3))
 242                 log.Print("Finished Get (expected success)")
 243         }
 244
 245         {
 246                 var rep int
 247                 var err error
 248                 hash2, rep, err = kc.PutB([]byte(""))
 249                 c.Check(hash2, Matches, `^d41d8cd98f00b204e9800998ecf8427e\+0(\+.+)?$`)
 250                 c.Check(rep, Equals, 2)
 251                 c.Check(err, Equals, nil)
 252                 log.Print("Finished PutB zero block")
 253         }
 254
 255         {
 256                 reader, blocklen, _, err := kc.Get("d41d8cd98f00b204e9800998ecf8427e")
 257                 c.Assert(err, Equals, nil)
 258                 all, err := ioutil.ReadAll(reader)
 259                 c.Check(all, DeepEquals, []byte(""))
 260                 c.Check(blocklen, Equals, int64(0))
 261                 log.Print("Finished Get zero block")
 262         }
 263 }
 264
 265 func (s *ServerRequiredSuite) TestPutAskGetForbidden(c *C) {
 266         kc := runProxy(c, nil, true)
 267         defer closeListener()
 268
 269         hash := fmt.Sprintf("%x", md5.Sum([]byte("bar")))
 270
 271         {
 272                 _, _, err := kc.Ask(hash)
 273                 errNotFound, _ := err.(keepclient.ErrNotFound)
 274                 c.Check(errNotFound, NotNil)
 275                 c.Assert(strings.Contains(err.Error(), "HTTP 403"), Equals, true)
 276                 log.Print("Ask 1")
 277         }
 278
 279         {
 280                 hash2, rep, err := kc.PutB([]byte("bar"))
 281                 c.Check(hash2, Equals, "")
 282                 c.Check(rep, Equals, 0)
 283                 c.Check(err, FitsTypeOf, keepclient.InsufficientReplicasError(errors.New("")))
 284                 log.Print("PutB")
 285         }
 286
 287         {
 288                 blocklen, _, err := kc.Ask(hash)
 289                 errNotFound, _ := err.(keepclient.ErrNotFound)
 290                 c.Check(errNotFound, NotNil)
 291                 c.Assert(strings.Contains(err.Error(), "HTTP 403"), Equals, true)
 292                 c.Check(blocklen, Equals, int64(0))
 293                 log.Print("Ask 2")
 294         }
 295
 296         {
 297                 _, blocklen, _, err := kc.Get(hash)
 298                 errNotFound, _ := err.(keepclient.ErrNotFound)
 299                 c.Check(errNotFound, NotNil)
 300                 c.Assert(strings.Contains(err.Error(), "HTTP 403"), Equals, true)
 301                 c.Check(blocklen, Equals, int64(0))
 302                 log.Print("Get")
 303         }
 304 }
 305
 306 func (s *ServerRequiredSuite) TestGetDisabled(c *C) {
 307         kc := runProxy(c, []string{"-no-get"}, false)
 308         defer closeListener()
 309
 310         hash := fmt.Sprintf("%x", md5.Sum([]byte("baz")))
 311
 312         {
 313                 _, _, err := kc.Ask(hash)
 314                 errNotFound, _ := err.(keepclient.ErrNotFound)
 315                 c.Check(errNotFound, NotNil)
 316                 c.Assert(strings.Contains(err.Error(), "HTTP 400"), Equals, true)
 317                 log.Print("Ask 1")
 318         }
 319
 320         {
 321                 hash2, rep, err := kc.PutB([]byte("baz"))
 322                 c.Check(hash2, Matches, fmt.Sprintf(`^%s\+3(\+.+)?$`, hash))
 323                 c.Check(rep, Equals, 2)
 324                 c.Check(err, Equals, nil)
 325                 log.Print("PutB")
 326         }
 327
 328         {
 329                 blocklen, _, err := kc.Ask(hash)
 330                 errNotFound, _ := err.(keepclient.ErrNotFound)
 331                 c.Check(errNotFound, NotNil)
 332                 c.Assert(strings.Contains(err.Error(), "HTTP 400"), Equals, true)
 333                 c.Check(blocklen, Equals, int64(0))
 334                 log.Print("Ask 2")
 335         }
 336
 337         {
 338                 _, blocklen, _, err := kc.Get(hash)
 339                 errNotFound, _ := err.(keepclient.ErrNotFound)
 340                 c.Check(errNotFound, NotNil)
 341                 c.Assert(strings.Contains(err.Error(), "HTTP 400"), Equals, true)
 342                 c.Check(blocklen, Equals, int64(0))
 343                 log.Print("Get")
 344         }
 345 }
 346
 347 func (s *ServerRequiredSuite) TestPutDisabled(c *C) {
 348         kc := runProxy(c, []string{"-no-put"}, false)
 349         defer closeListener()
 350
 351         hash2, rep, err := kc.PutB([]byte("quux"))
 352         c.Check(hash2, Equals, "")
 353         c.Check(rep, Equals, 0)
 354         c.Check(err, FitsTypeOf, keepclient.InsufficientReplicasError(errors.New("")))
 355 }
 356
 357 func (s *ServerRequiredSuite) TestCorsHeaders(c *C) {
 358         runProxy(c, nil, false)
 359         defer closeListener()
 360
 361         {
 362                 client := http.Client{}
 363                 req, err := http.NewRequest("OPTIONS",
 364                         fmt.Sprintf("http://%s/%x+3", listener.Addr().String(), md5.Sum([]byte("foo"))),
 365                         nil)
 366                 req.Header.Add("Access-Control-Request-Method", "PUT")
 367                 req.Header.Add("Access-Control-Request-Headers", "Authorization, X-Keep-Desired-Replicas")
 368                 resp, err := client.Do(req)
 369                 c.Check(err, Equals, nil)
 370                 c.Check(resp.StatusCode, Equals, 200)
 371                 body, err := ioutil.ReadAll(resp.Body)
 372                 c.Check(string(body), Equals, "")
 373                 c.Check(resp.Header.Get("Access-Control-Allow-Methods"), Equals, "GET, HEAD, POST, PUT, OPTIONS")
 374                 c.Check(resp.Header.Get("Access-Control-Allow-Origin"), Equals, "*")
 375         }
 376
 377         {
 378                 resp, err := http.Get(
 379                         fmt.Sprintf("http://%s/%x+3", listener.Addr().String(), md5.Sum([]byte("foo"))))
 380                 c.Check(err, Equals, nil)
 381                 c.Check(resp.Header.Get("Access-Control-Allow-Headers"), Equals, "Authorization, Content-Length, Content-Type, X-Keep-Desired-Replicas")
 382                 c.Check(resp.Header.Get("Access-Control-Allow-Origin"), Equals, "*")
 383         }
 384 }
 385
 386 func (s *ServerRequiredSuite) TestPostWithoutHash(c *C) {
 387         runProxy(c, nil, false)
 388         defer closeListener()
 389
 390         {
 391                 client := http.Client{}
 392                 req, err := http.NewRequest("POST",
 393                         "http://"+listener.Addr().String()+"/",
 394                         strings.NewReader("qux"))
 395                 req.Header.Add("Authorization", "OAuth2 4axaw8zxe0qm22wa6urpp5nskcne8z88cvbupv653y1njyi05h")
 396                 req.Header.Add("Content-Type", "application/octet-stream")
 397                 resp, err := client.Do(req)
 398                 c.Check(err, Equals, nil)
 399                 body, err := ioutil.ReadAll(resp.Body)
 400                 c.Check(err, Equals, nil)
 401                 c.Check(string(body), Matches,
 402                         fmt.Sprintf(`^%x\+3(\+.+)?$`, md5.Sum([]byte("qux"))))
 403         }
 404 }
 405
 406 func (s *ServerRequiredSuite) TestStripHint(c *C) {
 407         c.Check(removeHint.ReplaceAllString("http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73+K@zzzzz", "$1"),
 408                 Equals,
 409                 "http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73")
 410         c.Check(removeHint.ReplaceAllString("http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+K@zzzzz+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73", "$1"),
 411                 Equals,
 412                 "http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73")
 413         c.Check(removeHint.ReplaceAllString("http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73+K@zzzzz-zzzzz-zzzzzzzzzzzzzzz", "$1"),
 414                 Equals,
 415                 "http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73+K@zzzzz-zzzzz-zzzzzzzzzzzzzzz")
 416         c.Check(removeHint.ReplaceAllString("http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+K@zzzzz-zzzzz-zzzzzzzzzzzzzzz+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73", "$1"),
 417                 Equals,
 418                 "http://keep.zzzzz.arvadosapi.com:25107/2228819a18d3727630fa30c81853d23f+67108864+K@zzzzz-zzzzz-zzzzzzzzzzzzzzz+A37b6ab198qqqq28d903b975266b23ee711e1852c@55635f73")
 419
 420 }
 421
 422 // Test GetIndex
 423 //   Put one block, with 2 replicas
 424 //   With no prefix (expect the block locator, twice)
 425 //   With an existing prefix (expect the block locator, twice)
 426 //   With a valid but non-existing prefix (expect "\n")
 427 //   With an invalid prefix (expect error)
 428 func (s *ServerRequiredSuite) TestGetIndex(c *C) {
 429         kc := runProxy(c, nil, false)
 430         defer closeListener()
 431
 432         // Put "index-data" blocks
 433         data := []byte("index-data")
 434         hash := fmt.Sprintf("%x", md5.Sum(data))
 435
 436         hash2, rep, err := kc.PutB(data)
 437         c.Check(hash2, Matches, fmt.Sprintf(`^%s\+10(\+.+)?$`, hash))
 438         c.Check(rep, Equals, 2)
 439         c.Check(err, Equals, nil)
 440
 441         reader, blocklen, _, err := kc.Get(hash)
 442         c.Assert(err, Equals, nil)
 443         c.Check(blocklen, Equals, int64(10))
 444         all, err := ioutil.ReadAll(reader)
 445         c.Check(all, DeepEquals, data)
 446
 447         // Put some more blocks
 448         _, rep, err = kc.PutB([]byte("some-more-index-data"))
 449         c.Check(err, Equals, nil)
 450
 451         kc.Arvados.ApiToken = arvadostest.DataManagerToken
 452
 453         // Invoke GetIndex
 454         for _, spec := range []struct {
 455                 prefix         string
 456                 expectTestHash bool
 457                 expectOther    bool
 458         }{
 459                 {"", true, true},         // with no prefix
 460                 {hash[:3], true, false},  // with matching prefix
 461                 {"abcdef", false, false}, // with no such prefix
 462         } {
 463                 indexReader, err := kc.GetIndex(TestProxyUUID, spec.prefix)
 464                 c.Assert(err, Equals, nil)
 465                 indexResp, err := ioutil.ReadAll(indexReader)
 466                 c.Assert(err, Equals, nil)
 467                 locators := strings.Split(string(indexResp), "\n")
 468                 gotTestHash := 0
 469                 gotOther := 0
 470                 for _, locator := range locators {
 471                         if locator == "" {
 472                                 continue
 473                         }
 474                         c.Check(locator[:len(spec.prefix)], Equals, spec.prefix)
 475                         if locator[:32] == hash {
 476                                 gotTestHash++
 477                         } else {
 478                                 gotOther++
 479                         }
 480                 }
 481                 c.Check(gotTestHash == 2, Equals, spec.expectTestHash)
 482                 c.Check(gotOther > 0, Equals, spec.expectOther)
 483         }
 484
 485         // GetIndex with invalid prefix
 486         _, err = kc.GetIndex(TestProxyUUID, "xyz")
 487         c.Assert((err != nil), Equals, true)
 488 }
 489
 490 func (s *ServerRequiredSuite) TestPutAskGetInvalidToken(c *C) {
 491         kc := runProxy(c, nil, false)
 492         defer closeListener()
 493
 494         // Put a test block
 495         hash, rep, err := kc.PutB([]byte("foo"))
 496         c.Check(err, Equals, nil)
 497         c.Check(rep, Equals, 2)
 498
 499         for _, token := range []string{
 500                 "nosuchtoken",
 501                 "2ym314ysp27sk7h943q6vtc378srb06se3pq6ghurylyf3pdmx", // expired
 502         } {
 503                 // Change token to given bad token
 504                 kc.Arvados.ApiToken = token
 505
 506                 // Ask should result in error
 507                 _, _, err = kc.Ask(hash)
 508                 c.Check(err, NotNil)
 509                 errNotFound, _ := err.(keepclient.ErrNotFound)
 510                 c.Check(errNotFound.Temporary(), Equals, false)
 511                 c.Assert(strings.Contains(err.Error(), "HTTP 403"), Equals, true)
 512
 513                 // Get should result in error
 514                 _, _, _, err = kc.Get(hash)
 515                 c.Check(err, NotNil)
 516                 errNotFound, _ = err.(keepclient.ErrNotFound)
 517                 c.Check(errNotFound.Temporary(), Equals, false)
 518                 c.Assert(strings.Contains(err.Error(), "HTTP 403 \"Missing or invalid Authorization header\""), Equals, true)
 519         }
 520 }
 521
 522 func (s *ServerRequiredSuite) TestAskGetKeepProxyConnectionError(c *C) {
 523         arv, err := arvadosclient.MakeArvadosClient()
 524         c.Assert(err, Equals, nil)
 525
 526         // keepclient with no such keep server
 527         kc := keepclient.New(arv)
 528         locals := map[string]string{
 529                 TestProxyUUID: "http://localhost:12345",
 530         }
 531         kc.SetServiceRoots(locals, nil, nil)
 532
 533         // Ask should result in temporary connection refused error
 534         hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
 535         _, _, err = kc.Ask(hash)
 536         c.Check(err, NotNil)
 537         errNotFound, _ := err.(*keepclient.ErrNotFound)
 538         c.Check(errNotFound.Temporary(), Equals, true)
 539         c.Assert(strings.Contains(err.Error(), "connection refused"), Equals, true)
 540
 541         // Get should result in temporary connection refused error
 542         _, _, _, err = kc.Get(hash)
 543         c.Check(err, NotNil)
 544         errNotFound, _ = err.(*keepclient.ErrNotFound)
 545         c.Check(errNotFound.Temporary(), Equals, true)
 546         c.Assert(strings.Contains(err.Error(), "connection refused"), Equals, true)
 547 }
 548
 549 func (s *NoKeepServerSuite) TestAskGetNoKeepServerError(c *C) {
 550         kc := runProxy(c, nil, false)
 551         defer closeListener()
 552
 553         hash := fmt.Sprintf("%x", md5.Sum([]byte("foo")))
 554         for _, f := range []func() error{
 555                 func() error {
 556                         _, _, err := kc.Ask(hash)
 557                         return err
 558                 },
 559                 func() error {
 560                         _, _, _, err := kc.Get(hash)
 561                         return err
 562                 },
 563         } {
 564                 err := f()
 565                 c.Assert(err, NotNil)
 566                 errNotFound, _ := err.(*keepclient.ErrNotFound)
 567                 c.Check(errNotFound.Temporary(), Equals, true)
 568                 c.Check(err, ErrorMatches, `.*HTTP 502.*`)
 569         }
 570 }