Changed the default value for max_open_connections to one.

tornado_mysql/pools.py

@@ -14,7 +14,6 @@
 
 DEBUG = False
 
-
 def _debug(*msg):
     if DEBUG:
         print(*msg)
@@ -31,9 +30,9 @@ class Pool(object):
 
     def __init__(self,
                  connect_kwargs,
-                 max_idle_connections=1,
+                 max_open_connections,
+                 max_idle_connections=0,
                  max_recycle_sec=3600,
-                 max_open_connections=0,
                  io_loop=None,
                  ):
         """
@@ -47,7 +46,8 @@ def __init__(self,
         self.io_loop = io_loop or IOLoop.current()
         self.connect_kwargs = connect_kwargs
         self.max_idle = max_idle_connections
-        self.max_open = max_open_connections
+        if max_open_connections <= 0:
+            raise ValueError("max idle or open connections not initialized properly")
         self.max_recycle_sec = max_recycle_sec
 
         self._opened_conns = 0
@@ -73,7 +73,7 @@ def _get_conn(self):
             return fut
 
         # Open new connection
-        if self.max_open == 0 or self._opened_conns < self.max_open:
+        if self._opened_conns < self.max_open:
             self._opened_conns += 1
             _debug("Creating new connection:", self.stat())
             return connect(**self.connect_kwargs)