X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/570509ab4d2ef93d870fd2b1f2eab178afb1bad9..50128b53da4003912635b03fb27b5be2c5beaca1:/services/keepstore/handlers.go diff --git a/services/keepstore/handlers.go b/services/keepstore/handlers.go index 54b8b485e1..b51009ea4d 100644 --- a/services/keepstore/handlers.go +++ b/services/keepstore/handlers.go @@ -9,6 +9,7 @@ package main import ( "container/list" + "context" "crypto/md5" "encoding/json" "fmt" @@ -45,6 +46,9 @@ func MakeRESTRouter() *mux.Router { // Privileged client only. rest.HandleFunc(`/index/{prefix:[0-9a-f]{0,32}}`, IndexHandler).Methods("GET", "HEAD") + // Internals/debugging info (runtime.MemStats) + rest.HandleFunc(`/debug.json`, DebugHandler).Methods("GET", "HEAD") + // List volumes: path, device number, bytes used/avail. rest.HandleFunc(`/status.json`, StatusHandler).Methods("GET", "HEAD") @@ -71,6 +75,9 @@ func BadRequestHandler(w http.ResponseWriter, r *http.Request) { // GetBlockHandler is a HandleFunc to address Get block requests. func GetBlockHandler(resp http.ResponseWriter, req *http.Request) { + ctx, cancel := contextForResponse(context.TODO(), resp) + defer cancel() + if theConfig.RequireSignatures { locator := req.URL.Path[1:] // strip leading slash if err := VerifySignature(locator, GetAPIToken(req)); err != nil { @@ -86,14 +93,14 @@ func GetBlockHandler(resp http.ResponseWriter, req *http.Request) { // isn't here, we can return 404 now instead of waiting for a // buffer. - buf, err := getBufferForResponseWriter(resp, bufs, BlockSize) + buf, err := getBufferWithContext(ctx, bufs, BlockSize) if err != nil { http.Error(resp, err.Error(), http.StatusServiceUnavailable) return } defer bufs.Put(buf) - size, err := GetBlock(mux.Vars(req)["hash"], buf, resp) + size, err := GetBlock(ctx, mux.Vars(req)["hash"], buf, resp) if err != nil { code := http.StatusInternalServerError if err, ok := err.(*KeepError); ok { @@ -108,24 +115,33 @@ func GetBlockHandler(resp http.ResponseWriter, req *http.Request) { resp.Write(buf[:size]) } +// Return a new context that gets cancelled by resp's CloseNotifier. +func contextForResponse(parent context.Context, resp http.ResponseWriter) (context.Context, context.CancelFunc) { + ctx, cancel := context.WithCancel(parent) + if cn, ok := resp.(http.CloseNotifier); ok { + go func(c <-chan bool) { + select { + case <-c: + theConfig.debugLogf("cancel context") + cancel() + case <-ctx.Done(): + } + }(cn.CloseNotify()) + } + return ctx, cancel +} + // Get a buffer from the pool -- but give up and return a non-nil -// error if resp implements http.CloseNotifier and tells us that the -// client has disconnected before we get a buffer. -func getBufferForResponseWriter(resp http.ResponseWriter, bufs *bufferPool, bufSize int) ([]byte, error) { - var closeNotifier <-chan bool - if resp, ok := resp.(http.CloseNotifier); ok { - closeNotifier = resp.CloseNotify() - } - var buf []byte +// error if ctx ends before we get a buffer. +func getBufferWithContext(ctx context.Context, bufs *bufferPool, bufSize int) ([]byte, error) { bufReady := make(chan []byte) go func() { bufReady <- bufs.Get(bufSize) - close(bufReady) }() select { - case buf = <-bufReady: + case buf := <-bufReady: return buf, nil - case <-closeNotifier: + case <-ctx.Done(): go func() { // Even if closeNotifier happened first, we // need to keep waiting for our buf so we can @@ -138,6 +154,9 @@ func getBufferForResponseWriter(resp http.ResponseWriter, bufs *bufferPool, bufS // PutBlockHandler is a HandleFunc to address Put block requests. func PutBlockHandler(resp http.ResponseWriter, req *http.Request) { + ctx, cancel := contextForResponse(context.TODO(), resp) + defer cancel() + hash := mux.Vars(req)["hash"] // Detect as many error conditions as possible before reading @@ -159,7 +178,7 @@ func PutBlockHandler(resp http.ResponseWriter, req *http.Request) { return } - buf, err := getBufferForResponseWriter(resp, bufs, int(req.ContentLength)) + buf, err := getBufferWithContext(ctx, bufs, int(req.ContentLength)) if err != nil { http.Error(resp, err.Error(), http.StatusServiceUnavailable) return @@ -172,12 +191,15 @@ func PutBlockHandler(resp http.ResponseWriter, req *http.Request) { return } - replication, err := PutBlock(buf, hash) + replication, err := PutBlock(ctx, buf, hash) bufs.Put(buf) if err != nil { - ke := err.(*KeepError) - http.Error(resp, ke.Error(), ke.HTTPCode) + code := http.StatusInternalServerError + if err, ok := err.(*KeepError); ok { + code = err.HTTPCode + } + http.Error(resp, err.Error(), code) return } @@ -220,18 +242,6 @@ func IndexHandler(resp http.ResponseWriter, req *http.Request) { resp.Write([]byte{'\n'}) } -// StatusHandler -// Responds to /status.json requests with the current node status, -// described in a JSON structure. -// -// The data given in a status.json response includes: -// volumes - a list of Keep volumes currently in use by this server -// each volume is an object with the following fields: -// * mount_point -// * device_num (an integer identifying the underlying filesystem) -// * bytes_free -// * bytes_used - // PoolStatus struct type PoolStatus struct { Alloc uint64 `json:"BytesAllocated"` @@ -239,18 +249,37 @@ type PoolStatus struct { Len int `json:"BuffersInUse"` } +type volumeStatusEnt struct { + Label string + Status *VolumeStatus `json:",omitempty"` + VolumeStats *ioStats `json:",omitempty"` + InternalStats interface{} `json:",omitempty"` +} + // NodeStatus struct type NodeStatus struct { - Volumes []*VolumeStatus `json:"volumes"` + Volumes []*volumeStatusEnt BufferPool PoolStatus PullQueue WorkQueueStatus TrashQueue WorkQueueStatus - Memory runtime.MemStats } var st NodeStatus var stLock sync.Mutex +// DebugHandler addresses /debug.json requests. +func DebugHandler(resp http.ResponseWriter, req *http.Request) { + type debugStats struct { + MemStats runtime.MemStats + } + var ds debugStats + runtime.ReadMemStats(&ds.MemStats) + err := json.NewEncoder(resp).Encode(&ds) + if err != nil { + http.Error(resp, err.Error(), 500) + } +} + // StatusHandler addresses /status.json requests. func StatusHandler(resp http.ResponseWriter, req *http.Request) { stLock.Lock() @@ -270,20 +299,26 @@ func StatusHandler(resp http.ResponseWriter, req *http.Request) { func readNodeStatus(st *NodeStatus) { vols := KeepVM.AllReadable() if cap(st.Volumes) < len(vols) { - st.Volumes = make([]*VolumeStatus, len(vols)) + st.Volumes = make([]*volumeStatusEnt, len(vols)) } st.Volumes = st.Volumes[:0] for _, vol := range vols { - if s := vol.Status(); s != nil { - st.Volumes = append(st.Volumes, s) + var internalStats interface{} + if vol, ok := vol.(InternalStatser); ok { + internalStats = vol.InternalStats() } + st.Volumes = append(st.Volumes, &volumeStatusEnt{ + Label: vol.String(), + Status: vol.Status(), + InternalStats: internalStats, + //VolumeStats: KeepVM.VolumeStats(vol), + }) } st.BufferPool.Alloc = bufs.Alloc() st.BufferPool.Cap = bufs.Cap() st.BufferPool.Len = bufs.Len() st.PullQueue = getWorkQueueStatus(pullq) st.TrashQueue = getWorkQueueStatus(trashq) - runtime.ReadMemStats(&st.Memory) } // return a WorkQueueStatus for the given queue. If q is nil (which @@ -548,12 +583,17 @@ func UntrashHandler(resp http.ResponseWriter, req *http.Request) { // If the block found does not have the correct MD5 hash, returns // DiskHashError. // -func GetBlock(hash string, buf []byte, resp http.ResponseWriter) (int, error) { +func GetBlock(ctx context.Context, hash string, buf []byte, resp http.ResponseWriter) (int, error) { // Attempt to read the requested hash from a keep volume. errorToCaller := NotFoundError for _, vol := range KeepVM.AllReadable() { - size, err := vol.Get(hash, buf) + size, err := vol.Get(ctx, hash, buf) + select { + case <-ctx.Done(): + return 0, ErrClientDisconnect + default: + } if err != nil { // IsNotExist is an expected error and may be // ignored. All other errors are logged. In @@ -587,7 +627,7 @@ func GetBlock(hash string, buf []byte, resp http.ResponseWriter) (int, error) { // PutBlock Stores the BLOCK (identified by the content id HASH) in Keep. // -// PutBlock(block, hash) +// PutBlock(ctx, 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. @@ -612,7 +652,7 @@ func GetBlock(hash string, buf []byte, resp http.ResponseWriter) (int, error) { // all writes failed). The text of the error message should // provide as much detail as possible. // -func PutBlock(block []byte, hash string) (int, error) { +func PutBlock(ctx context.Context, block []byte, hash string) (int, error) { // Check that BLOCK's checksum matches HASH. blockhash := fmt.Sprintf("%x", md5.Sum(block)) if blockhash != hash { @@ -623,16 +663,21 @@ func PutBlock(block []byte, hash string) (int, error) { // 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 { + if n, err := CompareAndTouch(ctx, hash, block); err == nil || err == CollisionError { return n, err + } else if ctx.Err() != nil { + return 0, ErrClientDisconnect } // 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 { + if err := vol.Put(ctx, hash, block); err == nil { return vol.Replication(), nil // success! } + if ctx.Err() != nil { + return 0, ErrClientDisconnect + } } writables := KeepVM.AllWritable() @@ -643,7 +688,10 @@ func PutBlock(block []byte, hash string) (int, error) { allFull := true for _, vol := range writables { - err := vol.Put(hash, block) + err := vol.Put(ctx, hash, block) + if ctx.Err() != nil { + return 0, ErrClientDisconnect + } if err == nil { return vol.Replication(), nil // success! } @@ -669,10 +717,13 @@ func PutBlock(block []byte, hash string) (int, error) { // 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) { +func CompareAndTouch(ctx context.Context, hash string, buf []byte) (int, error) { var bestErr error = NotFoundError for _, vol := range KeepVM.AllWritable() { - if err := vol.Compare(hash, buf); err == CollisionError { + err := vol.Compare(ctx, hash, buf) + if ctx.Err() != nil { + return 0, ctx.Err() + } else if 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