move server defaults, delete defer cancel() in stream.go

server.go

@@ -61,6 +61,11 @@ import (
 	"google.golang.org/grpc/transport"
 )
 
+const (
+	defaultServerMaxReceiveMessageSize = 1024 * 1024 * 4
+	defaultServerMaxSendMessageSize    = 1024 * 1024 * 4
+)
+
 type methodHandler func(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor UnaryServerInterceptor) (interface{}, error)
 
 // MethodDesc represents an RPC service's method specification.