New mysql connection pool for Python, plus unit tests that verify that it's actually non-blocking. Some additional behavior in saranwrap, with tests that pass. Reviewd by Donovan.

indra/lib/python/indra/ipc/mysql_pool.py

@@ -0,0 +1,37 @@
+"""\
+@file mysql_pool.py
+@brief Uses saranwrap to implement a pool of nonblocking database connections to a mysql server.
+
+Copyright (c) 2007, Linden Research, Inc.
+$License$
+"""
+
+import os
+
+from eventlet.pools import Pool, DeadProcess
+from indra.ipc import saranwrap
+
+import MySQLdb
+
+class ConnectionPool(Pool):
+    """A pool which gives out saranwrapped MySQLdb connections from a pool
+    """
+    def __init__(self, min_size = 0, max_size = 4, *args, **kwargs):
+        self._args = args
+        self._kwargs = kwargs
+        Pool.__init__(self, min_size, max_size)
+
+    def create(self):
+        return saranwrap.wrap(MySQLdb).connect(*self._args, **self._kwargs)
+
+    def put(self, conn):
+        # poke the process to see if it's dead or None
+        try:
+            status = saranwrap.status(conn)
+        except (AttributeError, DeadProcess), e:
+            conn = self.create()
+
+        if conn:
+            Pool.put(self, conn)
+        else:
+            self.current_size -= 1