Merge pull request #312 from hxiaodon/master

filer server concern the lead change

3 files changed, 85 insertions, 7 deletions

diff --git a/weed/server/filer_server.go b/weed/server/filer_server.go
index ee7eaf886..767db3aea 100644
--- a/weed/server/filer_server.go
+++ b/weed/server/filer_server.go
@@ -1,8 +1,11 @@
 package weed_server
 
 import (
+	"math/rand"
 	"net/http"
 	"strconv"
+	"sync"
+	"time"
 
 	"github.com/chrislusf/seaweedfs/weed/filer"
 	"github.com/chrislusf/seaweedfs/weed/filer/cassandra_store"
@@ -11,17 +14,21 @@ import (
 	"github.com/chrislusf/seaweedfs/weed/filer/redis_store"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/security"
+	"github.com/chrislusf/seaweedfs/weed/storage"
+	"github.com/chrislusf/seaweedfs/weed/util"
 )
 
 type FilerServer struct {
 	port               string
 	master             string
+	mnLock             sync.RWMutex
 	collection         string
 	defaultReplication string
 	redirectOnRead     bool
 	disableDirListing  bool
 	secret             security.Secret
 	filer              filer.Filer
+	masterNodes        *storage.MasterNodes
 }
 
 func NewFilerServer(r *http.ServeMux, ip string, port int, master string, dir string, collection string,
@@ -59,9 +66,80 @@ func NewFilerServer(r *http.ServeMux, ip string, port int, master string, dir st
 
 	r.HandleFunc("/", fs.filerHandler)
 
+	go func() {
+		connected := true
+
+		fs.masterNodes = storage.NewMasterNodes(fs.master)
+		glog.V(0).Infof("Filer server bootstraps with master %s", fs.getMasterNode())
+
+		//force initialize with all available master nodes
+		fs.masterNodes.FindMaster()
+
+		for {
+			glog.V(4).Infof("Filer server sending to master %s", fs.getMasterNode())
+			master, err := fs.detectHealthyMaster(fs.getMasterNode())
+			if err == nil {
+				if !connected {
+					connected = true
+					if fs.getMasterNode() != master {
+						fs.setMasterNode(master)
+					}
+					glog.V(0).Infoln("Filer Server Connected with master at", master)
+				}
+			} else {
+				glog.V(1).Infof("Filer Server Failed to talk with master %s: %v", fs.getMasterNode(), err)
+				if connected {
+					connected = false
+				}
+			}
+			if connected {
+				time.Sleep(time.Duration(float32(10*1e3)*(1+rand.Float32())) * time.Millisecond)
+			} else {
+				time.Sleep(time.Duration(float32(10*1e3)*0.25) * time.Millisecond)
+			}
+		}
+	}()
+
 	return fs, nil
 }
 
 func (fs *FilerServer) jwt(fileId string) security.EncodedJwt {
 	return security.GenJwt(fs.secret, fileId)
 }
+
+func (fs *FilerServer) getMasterNode() string {
+	fs.mnLock.RLock()
+	defer fs.mnLock.RUnlock()
+	return fs.master
+}
+
+func (fs *FilerServer) setMasterNode(masterNode string) {
+	fs.mnLock.Lock()
+	defer fs.mnLock.Unlock()
+	fs.master = masterNode
+}
+
+func (fs *FilerServer) detectHealthyMaster(masterNode string) (master string, e error) {
+	statUrl := "http://" + masterNode + "/stats"
+	glog.V(4).Infof("Connecting to %s ...", statUrl)
+	_, e = util.Get(statUrl)
+	if e != nil {
+		fs.masterNodes.Reset()
+		for i := 0; i <= 3; i++ {
+			master, e = fs.masterNodes.FindMaster()
+			if e != nil {
+				continue
+			} else {
+				statUrl := "http://" + master + "/stats"
+				glog.V(4).Infof("Connecting to %s ...", statUrl)
+				_, e = util.Get(statUrl)
+				if e == nil {
+					break
+				}
+			}
+		}
+	} else {
+		master = masterNode
+	}
+	return
+}
diff --git a/weed/server/filer_server_handlers_read.go b/weed/server/filer_server_handlers_read.go
index ec61b0ab0..7b134581a 100644
--- a/weed/server/filer_server_handlers_read.go
+++ b/weed/server/filer_server_handlers_read.go
@@ -58,7 +58,7 @@ func (fs *FilerServer) GetOrHeadHandler(w http.ResponseWriter, r *http.Request,
 		return
 	}
 
-	urlLocation, err := operation.LookupFileId(fs.master, fileId)
+	urlLocation, err := operation.LookupFileId(fs.getMasterNode(), fileId)
 	if err != nil {
 		glog.V(1).Infoln("operation LookupFileId %s failed, err is %s", fileId, err.Error())
 		w.WriteHeader(http.StatusNotFound)
diff --git a/weed/server/filer_server_handlers_write.go b/weed/server/filer_server_handlers_write.go
index b446704f2..2aad20980 100644
--- a/weed/server/filer_server_handlers_write.go
+++ b/weed/server/filer_server_handlers_write.go
@@ -70,7 +70,7 @@ func (fs *FilerServer) PostHandler(w http.ResponseWriter, r *http.Request) {
 			return
 		} else if fileId != "" && err == nil {
 			var le error
-			urlLocation, le = operation.LookupFileId(fs.master, fileId)
+			urlLocation, le = operation.LookupFileId(fs.getMasterNode(), fileId)
 			if le != nil {
 				glog.V(1).Infoln("operation LookupFileId %s failed, err is %s", fileId, le.Error())
 				w.WriteHeader(http.StatusNotFound)
@@ -78,7 +78,7 @@ func (fs *FilerServer) PostHandler(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 	} else {
-		assignResult, ae := operation.Assign(fs.master, 1, replication, collection, query.Get("ttl"))
+		assignResult, ae := operation.Assign(fs.getMasterNode(), 1, replication, collection, query.Get("ttl"))
 		if ae != nil {
 			glog.V(0).Infoln("failing to assign a file id", ae.Error())
 			writeJsonError(w, r, http.StatusInternalServerError, ae)
@@ -132,7 +132,7 @@ func (fs *FilerServer) PostHandler(w http.ResponseWriter, r *http.Request) {
 		if ret.Name != "" {
 			path += ret.Name
 		} else {
-			operation.DeleteFile(fs.master, fileId, fs.jwt(fileId)) //clean up
+			operation.DeleteFile(fs.getMasterNode(), fileId, fs.jwt(fileId)) //clean up
 			glog.V(0).Infoln("Can not to write to folder", path, "without a file name!")
 			writeJsonError(w, r, http.StatusInternalServerError,
 				errors.New("Can not to write to folder "+path+" without a file name"))
@@ -143,13 +143,13 @@ func (fs *FilerServer) PostHandler(w http.ResponseWriter, r *http.Request) {
 	// also delete the old fid unless PUT operation
 	if r.Method != "PUT" {
 		if oldFid, err := fs.filer.FindFile(path); err == nil {
-			operation.DeleteFile(fs.master, oldFid, fs.jwt(oldFid))
+			operation.DeleteFile(fs.getMasterNode(), oldFid, fs.jwt(oldFid))
 		}
 	}
 
 	glog.V(4).Infoln("saving", path, "=>", fileId)
 	if db_err := fs.filer.CreateFile(path, fileId); db_err != nil {
-		operation.DeleteFile(fs.master, fileId, fs.jwt(fileId)) //clean up
+		operation.DeleteFile(fs.getMasterNode(), fileId, fs.jwt(fileId)) //clean up
 		glog.V(0).Infof("failing to write %s to filer server : %v", path, db_err)
 		writeJsonError(w, r, http.StatusInternalServerError, db_err)
 		return
@@ -176,7 +176,7 @@ func (fs *FilerServer) DeleteHandler(w http.ResponseWriter, r *http.Request) {
 	} else {
 		fid, err = fs.filer.DeleteFile(r.URL.Path)
 		if err == nil && fid != "" {
-			err = operation.DeleteFile(fs.master, fid, fs.jwt(fid))
+			err = operation.DeleteFile(fs.getMasterNode(), fid, fs.jwt(fid))
 		}
 	}
 	if err == nil {