put InMemStore into master package

go/cmd/master/master.go

@@ -6,7 +6,6 @@ import (
 	"net/rpc"
 	"strconv"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/namsral/flag"
@@ -15,26 +14,6 @@ import (
 	"github.com/PaddlePaddle/Paddle/go/master"
 )
 
-type inMemStore struct {
-	mu  sync.Mutex
-	buf []byte
-}
-
-func (m *inMemStore) Save(b []byte) error {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-
-	m.buf = b
-	return nil
-}
-
-func (m *inMemStore) Load() ([]byte, error) {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-
-	return m.buf, nil
-}
-
 func main() {
 	port := flag.Int("port", 8080, "port of the master server.")
 
@@ -58,7 +37,7 @@ func main() {
 			log.Fatal(err)
 		}
 	} else {
-		store = &inMemStore{}
+		store = &master.InMemStore{}
 	}
 
 	s, err := master.NewService(store, *chunkPerTask, *taskTimeoutDur, *taskTimeoutMax)

go/master/client_internal_test.go

@@ -32,19 +32,6 @@ func (a TestAddresser) Address() string {
 	return string(a)
 }
 
-type myStore struct {
-	buf []byte
-}
-
-func (m *myStore) Save(b []byte) error {
-	m.buf = b
-	return nil
-}
-
-func (m *myStore) Load() ([]byte, error) {
-	return m.buf, nil
-}
-
 func TestGetFinishTask(t *testing.T) {
 	const path = "/tmp/master_client_test_0"
 
@@ -60,7 +47,7 @@ func TestGetFinishTask(t *testing.T) {
 	}
 
 	go func(l net.Listener) {
-		s, err := NewService(&myStore{}, chunkPerTask, time.Second, 1)
+		s, err := NewService(&InMemStore{}, chunkPerTask, time.Second, 1)
 		if err != nil {
 			panic(err)
 		}

go/master/client_test.go

@@ -15,19 +15,6 @@ import (
 	"github.com/PaddlePaddle/recordio"
 )
 
-type myStore struct {
-	buf []byte
-}
-
-func (m *myStore) Save(b []byte) error {
-	m.buf = b
-	return nil
-}
-
-func (m *myStore) Load() ([]byte, error) {
-	return m.buf, nil
-}
-
 func TestNextRecord(t *testing.T) {
 	const (
 		path  = "/tmp/master_client_TestFull"
@@ -46,7 +33,7 @@ func TestNextRecord(t *testing.T) {
 	}
 
 	go func(l net.Listener) {
-		s, err := master.NewService(&myStore{}, 10, time.Second, 1)
+		s, err := master.NewService(&master.InMemStore{}, 10, time.Second, 1)
 		if err != nil {
 			panic(err)
 		}

go/master/inmem_store.go

@@ -0,0 +1,28 @@
+package master
+
+import "sync"
+
+// InMemStore is an in memory implementation of Store interface.
+//
+// It does not tolerate the fault that casues the program to crash.
+type InMemStore struct {
+	mu  sync.Mutex
+	buf []byte
+}
+
+// Save saves the state into the in-memory store.
+func (m *InMemStore) Save(state []byte) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	m.buf = state
+	return nil
+}
+
+// Load loads the state from the in-memory store.
+func (m *InMemStore) Load() ([]byte, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	return m.buf, nil
+}