services/datamanager/keep/keep.go

   1 /* Deals with getting Keep Server blocks from API Server and Keep Servers. */
   2
   3 package keep
   4
   5 import (
   6         "bufio"
   7         "encoding/json"
   8         "flag"
   9         "fmt"
  10         "git.curoverse.com/arvados.git/sdk/go/arvadosclient"
  11         "git.curoverse.com/arvados.git/sdk/go/blockdigest"
  12         "git.curoverse.com/arvados.git/sdk/go/logger"
  13         "git.curoverse.com/arvados.git/sdk/go/manifest"
  14         "git.curoverse.com/arvados.git/services/datamanager/loggerutil"
  15         "io/ioutil"
  16         "log"
  17         "net/http"
  18         "strconv"
  19         "strings"
  20         "sync"
  21         "time"
  22 )
  23
  24 type ServerAddress struct {
  25         Host string `json:"service_host"`
  26         Port int    `json:"service_port"`
  27         Uuid string `json:"uuid"`
  28 }
  29
  30 // Info about a particular block returned by the server
  31 type BlockInfo struct {
  32         Digest blockdigest.BlockDigest
  33         Size   int
  34         Mtime  int64 // TODO(misha): Replace this with a timestamp.
  35 }
  36
  37 // Info about a specified block given by a server
  38 type BlockServerInfo struct {
  39         ServerIndex int
  40         Size        int
  41         Mtime       int64 // TODO(misha): Replace this with a timestamp.
  42 }
  43
  44 type ServerContents struct {
  45         BlockDigestToInfo map[blockdigest.BlockDigest]BlockInfo
  46 }
  47
  48 type ServerResponse struct {
  49         Address  ServerAddress
  50         Contents ServerContents
  51 }
  52
  53 type ReadServers struct {
  54         ReadAllServers           bool
  55         KeepServerIndexToAddress []ServerAddress
  56         KeepServerAddressToIndex map[ServerAddress]int
  57         ServerToContents         map[ServerAddress]ServerContents
  58         BlockToServers           map[blockdigest.BlockDigest][]BlockServerInfo
  59         BlockReplicationCounts   map[int]int
  60 }
  61
  62 type GetKeepServersParams struct {
  63         Client arvadosclient.ArvadosClient
  64         Logger *logger.Logger
  65         Limit  int
  66 }
  67
  68 type KeepServiceList struct {
  69         ItemsAvailable int             `json:"items_available"`
  70         KeepServers    []ServerAddress `json:"items"`
  71 }
  72
  73 var (
  74         // Don't access the token directly, use getDataManagerToken() to
  75         // make sure it's been read.
  76         dataManagerToken             string
  77         dataManagerTokenFile         string
  78         dataManagerTokenFileReadOnce sync.Once
  79 )
  80
  81 func init() {
  82         flag.StringVar(&dataManagerTokenFile,
  83                 "data-manager-token-file",
  84                 "",
  85                 "File with the API token we should use to contact keep servers.")
  86 }
  87
  88 // TODO(misha): Change this to include the UUID as well.
  89 func (s ServerAddress) String() string {
  90         return s.HostPort()
  91 }
  92
  93 func (s ServerAddress) HostPort() string {
  94         return fmt.Sprintf("%s:%d", s.Host, s.Port)
  95 }
  96
  97 func getDataManagerToken(arvLogger *logger.Logger) string {
  98         readDataManagerToken := func() {
  99                 if dataManagerTokenFile == "" {
 100                         flag.Usage()
 101                         loggerutil.FatalWithMessage(arvLogger,
 102                                 "Data Manager Token needed, but data manager token file not specified.")
 103                 } else {
 104                         rawRead, err := ioutil.ReadFile(dataManagerTokenFile)
 105                         if err != nil {
 106                                 loggerutil.FatalWithMessage(arvLogger,
 107                                         fmt.Sprintf("Unexpected error reading token file %s: %v",
 108                                                 dataManagerTokenFile,
 109                                                 err))
 110                         }
 111                         dataManagerToken = strings.TrimSpace(string(rawRead))
 112                 }
 113         }
 114
 115         dataManagerTokenFileReadOnce.Do(readDataManagerToken)
 116         return dataManagerToken
 117 }
 118
 119 func GetKeepServersAndSummarize(params GetKeepServersParams) (results ReadServers) {
 120         results = GetKeepServers(params)
 121         log.Printf("Returned %d keep disks", len(results.ServerToContents))
 122
 123         results.Summarize(params.Logger)
 124         log.Printf("Replication level distribution: %v",
 125                 results.BlockReplicationCounts)
 126
 127         return
 128 }
 129
 130 func GetKeepServers(params GetKeepServersParams) (results ReadServers) {
 131         if &params.Client == nil {
 132                 log.Fatalf("params.Client passed to GetKeepServers() should " +
 133                         "contain a valid ArvadosClient, but instead it is nil.")
 134         }
 135
 136         sdkParams := arvadosclient.Dict{
 137                 "filters": [][]string{[]string{"service_type", "=", "disk"}},
 138         }
 139         if params.Limit > 0 {
 140                 sdkParams["limit"] = params.Limit
 141         }
 142
 143         var sdkResponse KeepServiceList
 144         err := params.Client.List("keep_services", sdkParams, &sdkResponse)
 145
 146         if err != nil {
 147                 loggerutil.FatalWithMessage(params.Logger,
 148                         fmt.Sprintf("Error requesting keep disks from API server: %v", err))
 149         }
 150
 151         if params.Logger != nil {
 152                 params.Logger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 153                         keepInfo := logger.GetOrCreateMap(p, "keep_info")
 154                         keepInfo["num_keep_servers_available"] = sdkResponse.ItemsAvailable
 155                         keepInfo["num_keep_servers_received"] = len(sdkResponse.KeepServers)
 156                         keepInfo["keep_servers"] = sdkResponse.KeepServers
 157                 })
 158         }
 159
 160         log.Printf("Received keep services list: %+v", sdkResponse)
 161
 162         if len(sdkResponse.KeepServers) < sdkResponse.ItemsAvailable {
 163                 loggerutil.FatalWithMessage(params.Logger,
 164                         fmt.Sprintf("Did not receive all available keep servers: %+v", sdkResponse))
 165         }
 166
 167         results.KeepServerIndexToAddress = sdkResponse.KeepServers
 168         results.KeepServerAddressToIndex = make(map[ServerAddress]int)
 169         for i, address := range results.KeepServerIndexToAddress {
 170                 results.KeepServerAddressToIndex[address] = i
 171         }
 172
 173         log.Printf("Got Server Addresses: %v", results)
 174
 175         // This is safe for concurrent use
 176         client := http.Client{}
 177
 178         // Send off all the index requests concurrently
 179         responseChan := make(chan ServerResponse)
 180         for _, keepServer := range sdkResponse.KeepServers {
 181                 // The above keepsServer variable is reused for each iteration, so
 182                 // it would be shared across all goroutines. This would result in
 183                 // us querying one server n times instead of n different servers
 184                 // as we intended. To avoid this we add it as an explicit
 185                 // parameter which gets copied. This bug and solution is described
 186                 // in https://golang.org/doc/effective_go.html#channels
 187                 go func(keepServer ServerAddress) {
 188                         responseChan <- GetServerContents(params.Logger,
 189                                 keepServer,
 190                                 client)
 191                 }(keepServer)
 192         }
 193
 194         results.ServerToContents = make(map[ServerAddress]ServerContents)
 195         results.BlockToServers = make(map[blockdigest.BlockDigest][]BlockServerInfo)
 196
 197         // Read all the responses
 198         for i := range sdkResponse.KeepServers {
 199                 _ = i // Here to prevent go from complaining.
 200                 response := <-responseChan
 201                 log.Printf("Received channel response from %v containing %d files",
 202                         response.Address,
 203                         len(response.Contents.BlockDigestToInfo))
 204                 results.ServerToContents[response.Address] = response.Contents
 205                 serverIndex := results.KeepServerAddressToIndex[response.Address]
 206                 for _, blockInfo := range response.Contents.BlockDigestToInfo {
 207                         results.BlockToServers[blockInfo.Digest] = append(
 208                                 results.BlockToServers[blockInfo.Digest],
 209                                 BlockServerInfo{ServerIndex: serverIndex,
 210                                         Size:  blockInfo.Size,
 211                                         Mtime: blockInfo.Mtime})
 212                 }
 213         }
 214         return
 215 }
 216
 217 func GetServerContents(arvLogger *logger.Logger,
 218         keepServer ServerAddress,
 219         client http.Client) (response ServerResponse) {
 220
 221         GetServerStatus(arvLogger, keepServer, client)
 222
 223         req := CreateIndexRequest(arvLogger, keepServer)
 224         resp, err := client.Do(req)
 225         if err != nil {
 226                 loggerutil.FatalWithMessage(arvLogger,
 227                         fmt.Sprintf("Error fetching %s: %v. Response was %+v",
 228                                 req.URL.String(),
 229                                 err,
 230                                 resp))
 231         }
 232
 233         return ReadServerResponse(arvLogger, keepServer, resp)
 234 }
 235
 236 func GetServerStatus(arvLogger *logger.Logger,
 237         keepServer ServerAddress,
 238         client http.Client) {
 239         url := fmt.Sprintf("http://%s:%d/status.json",
 240                 keepServer.Host,
 241                 keepServer.Port)
 242
 243         if arvLogger != nil {
 244                 now := time.Now()
 245                 arvLogger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 246                         keepInfo := logger.GetOrCreateMap(p, "keep_info")
 247                         serverInfo := make(map[string]interface{})
 248                         serverInfo["status_request_sent_at"] = now
 249                         serverInfo["host"] = keepServer.Host
 250                         serverInfo["port"] = keepServer.Port
 251
 252                         keepInfo[keepServer.Uuid] = serverInfo
 253                 })
 254         }
 255
 256         resp, err := client.Get(url)
 257         if err != nil {
 258                 loggerutil.FatalWithMessage(arvLogger,
 259                         fmt.Sprintf("Error getting keep status from %s: %v", url, err))
 260         } else if resp.StatusCode != 200 {
 261                 loggerutil.FatalWithMessage(arvLogger,
 262                         fmt.Sprintf("Received error code %d in response to request "+
 263                                 "for %s status: %s",
 264                                 resp.StatusCode, url, resp.Status))
 265         }
 266
 267         var keepStatus map[string]interface{}
 268         decoder := json.NewDecoder(resp.Body)
 269         decoder.UseNumber()
 270         err = decoder.Decode(&keepStatus)
 271         if err != nil {
 272                 loggerutil.FatalWithMessage(arvLogger,
 273                         fmt.Sprintf("Error decoding keep status from %s: %v", url, err))
 274         }
 275
 276         if arvLogger != nil {
 277                 now := time.Now()
 278                 arvLogger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 279                         keepInfo := logger.GetOrCreateMap(p, "keep_info")
 280                         serverInfo := keepInfo[keepServer.Uuid].(map[string]interface{})
 281                         serverInfo["status_response_processed_at"] = now
 282                         serverInfo["status"] = keepStatus
 283                 })
 284         }
 285 }
 286
 287 func CreateIndexRequest(arvLogger *logger.Logger,
 288         keepServer ServerAddress) (req *http.Request) {
 289         url := fmt.Sprintf("http://%s:%d/index", keepServer.Host, keepServer.Port)
 290         log.Println("About to fetch keep server contents from " + url)
 291
 292         if arvLogger != nil {
 293                 now := time.Now()
 294                 arvLogger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 295                         keepInfo := logger.GetOrCreateMap(p, "keep_info")
 296                         serverInfo := keepInfo[keepServer.Uuid].(map[string]interface{})
 297                         serverInfo["index_request_sent_at"] = now
 298                 })
 299         }
 300
 301         req, err := http.NewRequest("GET", url, nil)
 302         if err != nil {
 303                 loggerutil.FatalWithMessage(arvLogger,
 304                         fmt.Sprintf("Error building http request for %s: %v", url, err))
 305         }
 306
 307         req.Header.Add("Authorization",
 308                 fmt.Sprintf("OAuth2 %s", getDataManagerToken(arvLogger)))
 309         return
 310 }
 311
 312 func ReadServerResponse(arvLogger *logger.Logger,
 313         keepServer ServerAddress,
 314         resp *http.Response) (response ServerResponse) {
 315
 316         if resp.StatusCode != 200 {
 317                 loggerutil.FatalWithMessage(arvLogger,
 318                         fmt.Sprintf("Received error code %d in response to request "+
 319                                 "for %s index: %s",
 320                                 resp.StatusCode, keepServer.String(), resp.Status))
 321         }
 322
 323         if arvLogger != nil {
 324                 now := time.Now()
 325                 arvLogger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 326                         keepInfo := logger.GetOrCreateMap(p, "keep_info")
 327                         serverInfo := keepInfo[keepServer.Uuid].(map[string]interface{})
 328                         serverInfo["index_response_received_at"] = now
 329                 })
 330         }
 331
 332         response.Address = keepServer
 333         response.Contents.BlockDigestToInfo =
 334                 make(map[blockdigest.BlockDigest]BlockInfo)
 335         scanner := bufio.NewScanner(resp.Body)
 336         numLines, numDuplicates, numSizeDisagreements := 0, 0, 0
 337         for scanner.Scan() {
 338                 numLines++
 339                 blockInfo, err := parseBlockInfoFromIndexLine(scanner.Text())
 340                 if err != nil {
 341                         loggerutil.FatalWithMessage(arvLogger,
 342                                 fmt.Sprintf("Error parsing BlockInfo from index line "+
 343                                         "received from %s: %v",
 344                                         keepServer.String(),
 345                                         err))
 346                 }
 347
 348                 if storedBlock, ok := response.Contents.BlockDigestToInfo[blockInfo.Digest]; ok {
 349                         // This server returned multiple lines containing the same block digest.
 350                         numDuplicates += 1
 351                         if storedBlock.Size != blockInfo.Size {
 352                                 numSizeDisagreements += 1
 353                                 // TODO(misha): Consider failing here.
 354                                 message := fmt.Sprintf("Saw different sizes for the same block "+
 355                                         "on %s: %+v %+v",
 356                                         keepServer.String(),
 357                                         storedBlock,
 358                                         blockInfo)
 359                                 log.Println(message)
 360                                 if arvLogger != nil {
 361                                         arvLogger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 362                                                 keepInfo := logger.GetOrCreateMap(p, "keep_info")
 363                                                 serverInfo := keepInfo[keepServer.Uuid].(map[string]interface{})
 364                                                 var error_list []string
 365                                                 read_error_list, has_list := serverInfo["error_list"]
 366                                                 if has_list {
 367                                                         error_list = read_error_list.([]string)
 368                                                 } // If we didn't have the list, error_list is already an empty list
 369                                                 serverInfo["error_list"] = append(error_list, message)
 370                                         })
 371                                 }
 372                         }
 373                         // Keep the block that is bigger, or the block that's newer in
 374                         // the case of a size tie.
 375                         if storedBlock.Size < blockInfo.Size ||
 376                                 (storedBlock.Size == blockInfo.Size &&
 377                                         storedBlock.Mtime < blockInfo.Mtime) {
 378                                 response.Contents.BlockDigestToInfo[blockInfo.Digest] = blockInfo
 379                         }
 380                 } else {
 381                         response.Contents.BlockDigestToInfo[blockInfo.Digest] = blockInfo
 382                 }
 383         }
 384         if err := scanner.Err(); err != nil {
 385                 loggerutil.FatalWithMessage(arvLogger,
 386                         fmt.Sprintf("Received error scanning index response from %s: %v",
 387                                 keepServer.String(),
 388                                 err))
 389         } else {
 390                 log.Printf("%s index contained %d lines with %d duplicates with "+
 391                         "%d size disagreements",
 392                         keepServer.String(),
 393                         numLines,
 394                         numDuplicates,
 395                         numSizeDisagreements)
 396
 397                 if arvLogger != nil {
 398                         now := time.Now()
 399                         arvLogger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 400                                 keepInfo := logger.GetOrCreateMap(p, "keep_info")
 401                                 serverInfo := keepInfo[keepServer.Uuid].(map[string]interface{})
 402
 403                                 serverInfo["processing_finished_at"] = now
 404                                 serverInfo["lines_received"] = numLines
 405                                 serverInfo["duplicates_seen"] = numDuplicates
 406                                 serverInfo["size_disagreements_seen"] = numSizeDisagreements
 407                         })
 408                 }
 409         }
 410         resp.Body.Close()
 411         return
 412 }
 413
 414 func parseBlockInfoFromIndexLine(indexLine string) (blockInfo BlockInfo, err error) {
 415         tokens := strings.Fields(indexLine)
 416         if len(tokens) != 2 {
 417                 err = fmt.Errorf("Expected 2 tokens per line but received a "+
 418                         "line containing %v instead.",
 419                         tokens)
 420         }
 421
 422         var locator manifest.BlockLocator
 423         if locator, err = manifest.ParseBlockLocator(tokens[0]); err != nil {
 424                 err = fmt.Errorf("%v Received error while parsing line \"%s\"",
 425                         err, indexLine)
 426                 return
 427         }
 428         if len(locator.Hints) > 0 {
 429                 err = fmt.Errorf("Block locator in index line should not contain hints "+
 430                         "but it does: %v",
 431                         locator)
 432                 return
 433         }
 434
 435         blockInfo.Mtime, err = strconv.ParseInt(tokens[1], 10, 64)
 436         if err != nil {
 437                 return
 438         }
 439         blockInfo.Digest = locator.Digest
 440         blockInfo.Size = locator.Size
 441         return
 442 }
 443
 444 func (readServers *ReadServers) Summarize(arvLogger *logger.Logger) {
 445         readServers.BlockReplicationCounts = make(map[int]int)
 446         for _, infos := range readServers.BlockToServers {
 447                 replication := len(infos)
 448                 readServers.BlockReplicationCounts[replication] += 1
 449         }
 450
 451         if arvLogger != nil {
 452                 arvLogger.Update(func(p map[string]interface{}, e map[string]interface{}) {
 453                         keepInfo := logger.GetOrCreateMap(p, "keep_info")
 454                         keepInfo["distinct_blocks_stored"] = len(readServers.BlockToServers)
 455                 })
 456         }
 457
 458 }