// StatusHandler (GET /status.json)
import (
- "bytes"
"container/list"
"crypto/md5"
"encoding/json"
return rest
}
+// BadRequestHandler is a HandleFunc to address bad requests.
func BadRequestHandler(w http.ResponseWriter, r *http.Request) {
http.Error(w, BadRequestError.Error(), BadRequestError.HTTPCode)
}
+// GetBlockHandler is a HandleFunc to address Get block requests.
func GetBlockHandler(resp http.ResponseWriter, req *http.Request) {
- if enforce_permissions {
+ if enforcePermissions {
locator := req.URL.Path[1:] // strip leading slash
if err := VerifySignature(locator, GetApiToken(req)); err != nil {
http.Error(resp, err.Error(), err.(*KeepError).HTTPCode)
}
}
- block, err := GetBlock(mux.Vars(req)["hash"], false)
+ block, err := GetBlock(mux.Vars(req)["hash"])
if err != nil {
// This type assertion is safe because the only errors
// GetBlock can return are DiskHashError or NotFoundError.
resp.Write(block)
}
+// PutBlockHandler is a HandleFunc to address Put block requests.
func PutBlockHandler(resp http.ResponseWriter, req *http.Request) {
hash := mux.Vars(req)["hash"]
return
}
- if req.ContentLength > BLOCKSIZE {
+ if req.ContentLength > BlockSize {
http.Error(resp, TooLongError.Error(), TooLongError.HTTPCode)
return
}
return
}
- err = PutBlock(buf, hash)
+ replication, err := PutBlock(buf, hash)
bufs.Put(buf)
if err != nil {
// Success; add a size hint, sign the locator if possible, and
// return it to the client.
- return_hash := fmt.Sprintf("%s+%d", hash, req.ContentLength)
- api_token := GetApiToken(req)
- if PermissionSecret != nil && api_token != "" {
- expiry := time.Now().Add(blob_signature_ttl)
- return_hash = SignLocator(return_hash, api_token, expiry)
- }
- resp.Write([]byte(return_hash + "\n"))
+ returnHash := fmt.Sprintf("%s+%d", hash, req.ContentLength)
+ apiToken := GetApiToken(req)
+ if PermissionSecret != nil && apiToken != "" {
+ expiry := time.Now().Add(blobSignatureTTL)
+ returnHash = SignLocator(returnHash, apiToken, expiry)
+ }
+ resp.Header().Set("X-Keep-Replicas-Stored", strconv.Itoa(replication))
+ resp.Write([]byte(returnHash + "\n"))
}
-// IndexHandler
-// A HandleFunc to address /index and /index/{prefix} requests.
-//
+// IndexHandler is a HandleFunc to address /index and /index/{prefix} requests.
func IndexHandler(resp http.ResponseWriter, req *http.Request) {
// Reject unauthorized requests.
if !IsDataManagerToken(GetApiToken(req)) {
// * device_num (an integer identifying the underlying filesystem)
// * bytes_free
// * bytes_used
-//
-type VolumeStatus struct {
- MountPoint string `json:"mount_point"`
- DeviceNum uint64 `json:"device_num"`
- BytesFree uint64 `json:"bytes_free"`
- BytesUsed uint64 `json:"bytes_used"`
-}
+// PoolStatus struct
type PoolStatus struct {
Alloc uint64 `json:"BytesAllocated"`
Cap int `json:"BuffersMax"`
Len int `json:"BuffersInUse"`
}
+// NodeStatus struct
type NodeStatus struct {
Volumes []*VolumeStatus `json:"volumes"`
BufferPool PoolStatus
var st NodeStatus
var stLock sync.Mutex
+// StatusHandler addresses /status.json requests.
func StatusHandler(resp http.ResponseWriter, req *http.Request) {
stLock.Lock()
readNodeStatus(&st)
if err == nil {
resp.Write(jstat)
} else {
- log.Printf("json.Marshal: %s\n", err)
- log.Printf("NodeStatus = %v\n", &st)
+ log.Printf("json.Marshal: %s", err)
+ log.Printf("NodeStatus = %v", &st)
http.Error(resp, err.Error(), 500)
}
}
return
}
- if never_delete {
+ if neverDelete {
http.Error(resp, MethodDisabledError.Error(), MethodDisabledError.HTTPCode)
return
}
if body, err := json.Marshal(result); err == nil {
resp.Write(body)
} else {
- log.Printf("json.Marshal: %s (result = %v)\n", err, result)
+ log.Printf("json.Marshal: %s (result = %v)", err, result)
http.Error(resp, err.Error(), 500)
}
}
If the JSON unmarshalling fails, return 400 Bad Request.
*/
+// PullRequest consists of a block locator and an ordered list of servers
type PullRequest struct {
Locator string `json:"locator"`
Servers []string `json:"servers"`
}
+// PullHandler processes "PUT /pull" requests for the data manager.
func PullHandler(resp http.ResponseWriter, req *http.Request) {
// Reject unauthorized requests.
if !IsDataManagerToken(GetApiToken(req)) {
pullq.ReplaceQueue(plist)
}
+// TrashRequest consists of a block locator and it's Mtime
type TrashRequest struct {
Locator string `json:"locator"`
BlockMtime int64 `json:"block_mtime"`
}
+// TrashHandler processes /trash requests.
func TrashHandler(resp http.ResponseWriter, req *http.Request) {
// Reject unauthorized requests.
if !IsDataManagerToken(GetApiToken(req)) {
// should be the only part of the code that cares about which volume a
// block is stored on, so it should be responsible for figuring out
// which volume to check for fetching blocks, storing blocks, etc.
-
// ==============================
-// GetBlock fetches and returns the block identified by "hash". If
-// the update_timestamp argument is true, GetBlock also updates the
-// block's file modification time (for the sake of PutBlock, which
-// must update the file's timestamp when the block already exists).
+
+// GetBlock fetches and returns the block identified by "hash".
//
// On success, GetBlock returns a byte slice with the block data, and
// a nil error.
// If the block found does not have the correct MD5 hash, returns
// DiskHashError.
//
-
-func GetBlock(hash string, update_timestamp bool) ([]byte, error) {
+func GetBlock(hash string) ([]byte, error) {
// Attempt to read the requested hash from a keep volume.
- error_to_caller := NotFoundError
-
- var vols []Volume
- if update_timestamp {
- // Pointless to find the block on an unwritable volume
- // because Touch() will fail -- this is as good as
- // "not found" for purposes of callers who need to
- // update_timestamp.
- vols = KeepVM.AllWritable()
- } else {
- vols = KeepVM.AllReadable()
- }
+ errorToCaller := NotFoundError
- for _, vol := range vols {
+ for _, vol := range KeepVM.AllReadable() {
buf, err := vol.Get(hash)
if err != nil {
// IsNotExist is an expected error and may be
// volumes. If all volumes report IsNotExist,
// we return a NotFoundError.
if !os.IsNotExist(err) {
- log.Printf("GetBlock: reading %s: %s\n", hash, err)
+ log.Printf("%s: Get(%s): %s", vol, hash, err)
}
continue
}
if filehash != hash {
// TODO: Try harder to tell a sysadmin about
// this.
- log.Printf("%s: checksum mismatch for request %s (actual %s)\n",
+ log.Printf("%s: checksum mismatch for request %s (actual %s)",
vol, hash, filehash)
- error_to_caller = DiskHashError
+ errorToCaller = DiskHashError
bufs.Put(buf)
continue
}
- if error_to_caller == DiskHashError {
+ if errorToCaller == DiskHashError {
log.Printf("%s: checksum mismatch for request %s but a good copy was found on another volume and returned",
vol, hash)
}
- if update_timestamp {
- if err := vol.Touch(hash); err != nil {
- error_to_caller = GenericError
- log.Printf("%s: Touch %s failed: %s",
- vol, hash, error_to_caller)
- bufs.Put(buf)
- continue
- }
- }
return buf, nil
}
- return nil, error_to_caller
+ return nil, errorToCaller
}
-/* PutBlock(block, hash)
- Stores the BLOCK (identified by the content id HASH) in Keep.
-
- The MD5 checksum of the block must be identical to the content id HASH.
- If not, an error is returned.
-
- PutBlock stores the BLOCK on the first Keep volume with free space.
- A failure code is returned to the user only if all volumes fail.
-
- On success, PutBlock returns nil.
- On failure, it returns a KeepError with one of the following codes:
-
- 500 Collision
- A different block with the same hash already exists on this
- Keep server.
- 422 MD5Fail
- The MD5 hash of the BLOCK does not match the argument HASH.
- 503 Full
- There was not enough space left in any Keep volume to store
- the object.
- 500 Fail
- The object could not be stored for some other reason (e.g.
- all writes failed). The text of the error message should
- provide as much detail as possible.
-*/
-
-func PutBlock(block []byte, hash string) error {
+// PutBlock Stores the BLOCK (identified by the content id HASH) in Keep.
+//
+// PutBlock(block, hash)
+// Stores the BLOCK (identified by the content id HASH) in Keep.
+//
+// The MD5 checksum of the block must be identical to the content id HASH.
+// If not, an error is returned.
+//
+// PutBlock stores the BLOCK on the first Keep volume with free space.
+// A failure code is returned to the user only if all volumes fail.
+//
+// On success, PutBlock returns nil.
+// On failure, it returns a KeepError with one of the following codes:
+//
+// 500 Collision
+// A different block with the same hash already exists on this
+// Keep server.
+// 422 MD5Fail
+// The MD5 hash of the BLOCK does not match the argument HASH.
+// 503 Full
+// There was not enough space left in any Keep volume to store
+// the object.
+// 500 Fail
+// The object could not be stored for some other reason (e.g.
+// all writes failed). The text of the error message should
+// provide as much detail as possible.
+//
+func PutBlock(block []byte, hash string) (int, error) {
// Check that BLOCK's checksum matches HASH.
blockhash := fmt.Sprintf("%x", md5.Sum(block))
if blockhash != hash {
log.Printf("%s: MD5 checksum %s did not match request", hash, blockhash)
- return RequestHashError
- }
-
- // If we already have a block on disk under this identifier, return
- // success (but check for MD5 collisions). While fetching the block,
- // update its timestamp.
- // The only errors that GetBlock can return are DiskHashError and NotFoundError.
- // In either case, we want to write our new (good) block to disk,
- // so there is nothing special to do if err != nil.
- //
- if oldblock, err := GetBlock(hash, true); err == nil {
- defer bufs.Put(oldblock)
- if bytes.Compare(block, oldblock) == 0 {
- // The block already exists; return success.
- return nil
- } else {
- return CollisionError
- }
+ return 0, RequestHashError
+ }
+
+ // If we already have this data, it's intact on disk, and we
+ // can update its timestamp, return success. If we have
+ // different data with the same hash, return failure.
+ if n, err := CompareAndTouch(hash, block); err == nil || err == CollisionError {
+ return n, err
}
// Choose a Keep volume to write to.
// If this volume fails, try all of the volumes in order.
if vol := KeepVM.NextWritable(); vol != nil {
if err := vol.Put(hash, block); err == nil {
- return nil // success!
+ return vol.Replication(), nil // success!
}
}
writables := KeepVM.AllWritable()
if len(writables) == 0 {
log.Print("No writable volumes.")
- return FullError
+ return 0, FullError
}
allFull := true
for _, vol := range writables {
err := vol.Put(hash, block)
if err == nil {
- return nil // success!
+ return vol.Replication(), nil // success!
}
if err != FullError {
// The volume is not full but the
// write did not succeed. Report the
// error and continue trying.
allFull = false
- log.Printf("%s: Write(%s): %s\n", vol, hash, err)
+ log.Printf("%s: Write(%s): %s", vol, hash, err)
}
}
if allFull {
log.Print("All volumes are full.")
- return FullError
- } else {
- // Already logged the non-full errors.
- return GenericError
+ return 0, FullError
+ }
+ // Already logged the non-full errors.
+ return 0, GenericError
+}
+
+// CompareAndTouch returns the current replication level if one of the
+// volumes already has the given content and it successfully updates
+// the relevant block's modification time in order to protect it from
+// premature garbage collection. Otherwise, it returns a non-nil
+// error.
+func CompareAndTouch(hash string, buf []byte) (int, error) {
+ var bestErr error = NotFoundError
+ for _, vol := range KeepVM.AllWritable() {
+ if err := vol.Compare(hash, buf); err == CollisionError {
+ // Stop if we have a block with same hash but
+ // different content. (It will be impossible
+ // to tell which one is wanted if we have
+ // both, so there's no point writing it even
+ // on a different volume.)
+ log.Printf("%s: Compare(%s): %s", vol, hash, err)
+ return 0, err
+ } else if os.IsNotExist(err) {
+ // Block does not exist. This is the only
+ // "normal" error: we don't log anything.
+ continue
+ } else if err != nil {
+ // Couldn't open file, data is corrupt on
+ // disk, etc.: log this abnormal condition,
+ // and try the next volume.
+ log.Printf("%s: Compare(%s): %s", vol, hash, err)
+ continue
+ }
+ if err := vol.Touch(hash); err != nil {
+ log.Printf("%s: Touch %s failed: %s", vol, hash, err)
+ bestErr = err
+ continue
+ }
+ // Compare and Touch both worked --> done.
+ return vol.Replication(), nil
}
+ return 0, bestErr
}
var validLocatorRe = regexp.MustCompile(`^[0-9a-f]{32}$`)
-// IsValidLocator
-// Return true if the specified string is a valid Keep locator.
-// When Keep is extended to support hash types other than MD5,
-// this should be updated to cover those as well.
+// IsValidLocator returns true if the specified string is a valid Keep locator.
+// When Keep is extended to support hash types other than MD5,
+// this should be updated to cover those as well.
//
func IsValidLocator(loc string) bool {
return validLocatorRe.MatchString(loc)
}
// IsExpired returns true if the given Unix timestamp (expressed as a
-// hexadecimal string) is in the past, or if timestamp_hex cannot be
+// hexadecimal string) is in the past, or if timestampHex cannot be
// parsed as a hexadecimal string.
-func IsExpired(timestamp_hex string) bool {
- ts, err := strconv.ParseInt(timestamp_hex, 16, 0)
+func IsExpired(timestampHex string) bool {
+ ts, err := strconv.ParseInt(timestampHex, 16, 0)
if err != nil {
- log.Printf("IsExpired: %s\n", err)
+ log.Printf("IsExpired: %s", err)
return true
}
return time.Unix(ts, 0).Before(time.Now())
}
-// CanDelete returns true if the user identified by api_token is
+// CanDelete returns true if the user identified by apiToken is
// allowed to delete blocks.
-func CanDelete(api_token string) bool {
- if api_token == "" {
+func CanDelete(apiToken string) bool {
+ if apiToken == "" {
return false
}
// Blocks may be deleted only when Keep has been configured with a
// data manager.
- if IsDataManagerToken(api_token) {
+ if IsDataManagerToken(apiToken) {
return true
}
- // TODO(twp): look up api_token with the API server
+ // TODO(twp): look up apiToken with the API server
// return true if is_admin is true and if the token
// has unlimited scope
return false
}
-// IsDataManagerToken returns true if api_token represents the data
+// IsDataManagerToken returns true if apiToken represents the data
// manager's token.
-func IsDataManagerToken(api_token string) bool {
- return data_manager_token != "" && api_token == data_manager_token
+func IsDataManagerToken(apiToken string) bool {
+ return dataManagerToken != "" && apiToken == dataManagerToken
}
projects / arvados.git / blobdiff