sdk/go/keepclient/support.go

   1 package keepclient
   2
   3 import (
   4         "crypto/md5"
   5         "errors"
   6         "fmt"
   7         "io"
   8         "io/ioutil"
   9         "log"
  10         "math/rand"
  11         "net/http"
  12         "os"
  13         "regexp"
  14         "strings"
  15
  16         "git.curoverse.com/arvados.git/sdk/go/streamer"
  17 )
  18
  19 // Function used to emit debug messages. The easiest way to enable
  20 // keepclient debug messages in your application is to assign
  21 // log.Printf to DebugPrintf.
  22 var DebugPrintf = func(string, ...interface{}) {}
  23
  24 func init() {
  25         var matchTrue = regexp.MustCompile("^(?i:1|yes|true)$")
  26         if matchTrue.MatchString(os.Getenv("ARVADOS_DEBUG")) {
  27                 DebugPrintf = log.Printf
  28         }
  29 }
  30
  31 type keepService struct {
  32         Uuid     string `json:"uuid"`
  33         Hostname string `json:"service_host"`
  34         Port     int    `json:"service_port"`
  35         SSL      bool   `json:"service_ssl_flag"`
  36         SvcType  string `json:"service_type"`
  37         ReadOnly bool   `json:"read_only"`
  38 }
  39
  40 // Md5String returns md5 hash for the bytes in the given string
  41 func Md5String(s string) string {
  42         return fmt.Sprintf("%x", md5.Sum([]byte(s)))
  43 }
  44
  45 type svcList struct {
  46         Items []keepService `json:"items"`
  47 }
  48
  49 type uploadStatus struct {
  50         err             error
  51         url             string
  52         statusCode      int
  53         replicas_stored int
  54         response        string
  55 }
  56
  57 func (this *KeepClient) uploadToKeepServer(host string, hash string, body io.ReadCloser,
  58         upload_status chan<- uploadStatus, expectedLength int64, requestID int32) {
  59
  60         var req *http.Request
  61         var err error
  62         var url = fmt.Sprintf("%s/%s", host, hash)
  63         if req, err = http.NewRequest("PUT", url, nil); err != nil {
  64                 DebugPrintf("DEBUG: [%08x] Error creating request PUT %v error: %v", requestID, url, err.Error())
  65                 upload_status <- uploadStatus{err, url, 0, 0, ""}
  66                 body.Close()
  67                 return
  68         }
  69
  70         req.ContentLength = expectedLength
  71         if expectedLength > 0 {
  72                 // Do() will close the body ReadCloser when it is done
  73                 // with it.
  74                 req.Body = body
  75         } else {
  76                 // "For client requests, a value of 0 means unknown if Body is
  77                 // not nil."  In this case we do want the body to be empty, so
  78                 // don't set req.Body.  However, we still need to close the
  79                 // body ReadCloser.
  80                 body.Close()
  81         }
  82
  83         req.Header.Add("Authorization", fmt.Sprintf("OAuth2 %s", this.Arvados.ApiToken))
  84         req.Header.Add("Content-Type", "application/octet-stream")
  85         req.Header.Add(X_Keep_Desired_Replicas, fmt.Sprint(this.Want_replicas))
  86
  87         var resp *http.Response
  88         if resp, err = this.httpClient().Do(req); err != nil {
  89                 DebugPrintf("DEBUG: [%08x] Upload failed %v error: %v", requestID, url, err.Error())
  90                 upload_status <- uploadStatus{err, url, 0, 0, ""}
  91                 return
  92         }
  93
  94         rep := 1
  95         if xr := resp.Header.Get(X_Keep_Replicas_Stored); xr != "" {
  96                 fmt.Sscanf(xr, "%d", &rep)
  97         }
  98
  99         defer resp.Body.Close()
 100         defer io.Copy(ioutil.Discard, resp.Body)
 101
 102         respbody, err2 := ioutil.ReadAll(&io.LimitedReader{R: resp.Body, N: 4096})
 103         response := strings.TrimSpace(string(respbody))
 104         if err2 != nil && err2 != io.EOF {
 105                 DebugPrintf("DEBUG: [%08x] Upload %v error: %v response: %v", requestID, url, err2.Error(), response)
 106                 upload_status <- uploadStatus{err2, url, resp.StatusCode, rep, response}
 107         } else if resp.StatusCode == http.StatusOK {
 108                 DebugPrintf("DEBUG: [%08x] Upload %v success", requestID, url)
 109                 upload_status <- uploadStatus{nil, url, resp.StatusCode, rep, response}
 110         } else {
 111                 if resp.StatusCode >= 300 && response == "" {
 112                         response = resp.Status
 113                 }
 114                 DebugPrintf("DEBUG: [%08x] Upload %v error: %v response: %v", requestID, url, resp.StatusCode, response)
 115                 upload_status <- uploadStatus{errors.New(resp.Status), url, resp.StatusCode, rep, response}
 116         }
 117 }
 118
 119 func (this *KeepClient) putReplicas(
 120         hash string,
 121         tr *streamer.AsyncStream,
 122         expectedLength int64) (locator string, replicas int, err error) {
 123
 124         // Generate an arbitrary ID to identify this specific
 125         // transaction in debug logs.
 126         requestID := rand.Int31()
 127
 128         // Calculate the ordering for uploading to servers
 129         sv := NewRootSorter(this.WritableLocalRoots(), hash).GetSortedRoots()
 130
 131         // The next server to try contacting
 132         next_server := 0
 133
 134         // The number of active writers
 135         active := 0
 136
 137         // Used to communicate status from the upload goroutines
 138         upload_status := make(chan uploadStatus)
 139         defer func() {
 140                 // Wait for any abandoned uploads (e.g., we started
 141                 // two uploads and the first replied with replicas=2)
 142                 // to finish before closing the status channel.
 143                 go func() {
 144                         for active > 0 {
 145                                 <-upload_status
 146                         }
 147                         close(upload_status)
 148                 }()
 149         }()
 150
 151         replicasDone := 0
 152         replicasTodo := this.Want_replicas
 153
 154         replicasPerThread := this.replicasPerService
 155         if replicasPerThread < 1 {
 156                 // unlimited or unknown
 157                 replicasPerThread = replicasTodo
 158         }
 159
 160         retriesRemaining := 1 + this.Retries
 161         var retryServers []string
 162
 163         lastError := make(map[string]string)
 164
 165         for retriesRemaining > 0 {
 166                 retriesRemaining -= 1
 167                 next_server = 0
 168                 retryServers = []string{}
 169                 for replicasTodo > 0 {
 170                         for active*replicasPerThread < replicasTodo {
 171                                 // Start some upload requests
 172                                 if next_server < len(sv) {
 173                                         DebugPrintf("DEBUG: [%08x] Begin upload %s to %s", requestID, hash, sv[next_server])
 174                                         go this.uploadToKeepServer(sv[next_server], hash, tr.MakeStreamReader(), upload_status, expectedLength, requestID)
 175                                         next_server += 1
 176                                         active += 1
 177                                 } else {
 178                                         if active == 0 && retriesRemaining == 0 {
 179                                                 msg := "Could not write sufficient replicas: "
 180                                                 for _, resp := range lastError {
 181                                                         msg += resp + "; "
 182                                                 }
 183                                                 msg = msg[:len(msg)-2]
 184                                                 return locator, replicasDone, InsufficientReplicasError(errors.New(msg))
 185                                         } else {
 186                                                 break
 187                                         }
 188                                 }
 189                         }
 190                         DebugPrintf("DEBUG: [%08x] Replicas remaining to write: %v active uploads: %v",
 191                                 requestID, replicasTodo, active)
 192
 193                         // Now wait for something to happen.
 194                         if active > 0 {
 195                                 status := <-upload_status
 196                                 active -= 1
 197
 198                                 if status.statusCode == 200 {
 199                                         // good news!
 200                                         replicasDone += status.replicas_stored
 201                                         replicasTodo -= status.replicas_stored
 202                                         locator = status.response
 203                                         delete(lastError, status.url)
 204                                 } else {
 205                                         msg := fmt.Sprintf("[%d] %s", status.statusCode, status.response)
 206                                         if len(msg) > 100 {
 207                                                 msg = msg[:100]
 208                                         }
 209                                         lastError[status.url] = msg
 210                                 }
 211
 212                                 if status.statusCode == 0 || status.statusCode == 408 || status.statusCode == 429 ||
 213                                         (status.statusCode >= 500 && status.statusCode != 503) {
 214                                         // Timeout, too many requests, or other server side failure
 215                                         // Do not retry when status code is 503, which means the keep server is full
 216                                         retryServers = append(retryServers, status.url[0:strings.LastIndex(status.url, "/")])
 217                                 }
 218                         } else {
 219                                 break
 220                         }
 221                 }
 222
 223                 sv = retryServers
 224         }
 225
 226         return locator, replicasDone, nil
 227 }