etcdserver: Create MemberDir() and base {Snap,WAL}Dir() thereon. Audit DataDir.

etcdserver/config.go

@@ -83,9 +83,11 @@ func (c *ServerConfig) VerifyBootstrapConfig() error {
 	return nil
 }
 
-func (c *ServerConfig) WALDir() string { return path.Join(c.DataDir, "wal") }
+func (c *ServerConfig) MemberDir() string { return path.Join(c.DataDir, "member") }
 
-func (c *ServerConfig) SnapDir() string { return path.Join(c.DataDir, "snap") }
+func (c *ServerConfig) WALDir() string { return path.Join(c.MemberDir(), "wal") }
+
+func (c *ServerConfig) SnapDir() string { return path.Join(c.MemberDir(), "snap") }
 
 func (c *ServerConfig) ShouldDiscover() bool { return c.DiscoveryURL != "" }
 
@@ -99,6 +101,7 @@ func (c *ServerConfig) print(initial bool) {
 		log.Println("etcdserver: force new cluster")
 	}
 	log.Printf("etcdserver: data dir = %s", c.DataDir)
+	log.Printf("etcdserver: member dir = %s", c.MemberDir())
 	log.Printf("etcdserver: heartbeat = %dms", c.TickMs)
 	log.Printf("etcdserver: election = %dms", c.ElectionTicks*int(c.TickMs))
 	log.Printf("etcdserver: snapshot count = %d", c.SnapCount)

etcdserver/config_test.go

@@ -129,8 +129,8 @@ func TestBootstrapConfigVerify(t *testing.T) {
 
 func TestSnapDir(t *testing.T) {
 	tests := map[string]string{
-		"/":            "/snap",
-		"/var/lib/etc": "/var/lib/etc/snap",
+		"/":            "/member/snap",
+		"/var/lib/etc": "/var/lib/etc/member/snap",
 	}
 	for dd, w := range tests {
 		cfg := ServerConfig{
@@ -144,8 +144,8 @@ func TestSnapDir(t *testing.T) {
 
 func TestWALDir(t *testing.T) {
 	tests := map[string]string{
-		"/":            "/wal",
-		"/var/lib/etc": "/var/lib/etc/wal",
+		"/":            "/member/wal",
+		"/var/lib/etc": "/var/lib/etc/member/wal",
 	}
 	for dd, w := range tests {
 		cfg := ServerConfig{

etcdserver/server.go

@@ -145,16 +145,13 @@ func NewServer(cfg *ServerConfig) (*EtcdServer, error) {
 	var s *raft.MemoryStorage
 	var id types.ID
 	var ss *snap.Snapshotter
-	baseDataDir := cfg.DataDir
-	// Data dir lives under member now.
-	cfg.DataDir = path.Join(cfg.DataDir, "member")
 
-	walVersion, err := wal.DetectVersion(baseDataDir)
+	walVersion, err := wal.DetectVersion(cfg.DataDir)
 	if err != nil {
 		return nil, err
 	}
 	if walVersion == wal.WALUnknown {
-		return nil, fmt.Errorf("unknown wal version in data dir %s", baseDataDir)
+		return nil, fmt.Errorf("unknown wal version in data dir %s", cfg.DataDir)
 	}
 	haveWAL := walVersion != wal.WALNotExist
 
@@ -194,7 +191,7 @@ func NewServer(cfg *ServerConfig) (*EtcdServer, error) {
 		id, n, s, w = startNode(cfg, cfg.Cluster.MemberIDs())
 	case haveWAL:
 		// Run the migrations.
-		if err := upgradeWAL(baseDataDir, cfg.Name, walVersion); err != nil {
+		if err := upgradeWAL(cfg.DataDir, cfg.Name, walVersion); err != nil {
 			return nil, err
 		}
 
@@ -202,6 +199,10 @@ func NewServer(cfg *ServerConfig) (*EtcdServer, error) {
 			return nil, fmt.Errorf("cannot write to data directory: %v", err)
 		}
 
+		if err := fileutil.IsDirWriteable(cfg.MemberDir()); err != nil {
+			return nil, fmt.Errorf("cannot write to member directory: %v", err)
+		}
+
 		if cfg.ShouldDiscover() {
 			log.Printf("etcdserver: discovery token ignored since a cluster has already been initialized. Valid log found at %q", cfg.WALDir())
 		}