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--- a
+++ b/Ming/ming/datastore.py
@@ -0,0 +1,123 @@
+from __future__ import with_statement
+import time
+import logging
+
+from threading import Lock
+
+from pymongo.connection import Connection
+from pymongo.master_slave_connection import MasterSlaveConnection
+
+from .utils import parse_uri
+
+log = logging.getLogger(__name__)
+
+class tl_property(object):
+
+    def __init__(self, tl_attr='_tl_value'):
+        self.tl_attr = tl_attr
+        self.name = self.func = None
+
+    def __call__(self, func):
+        self.func = func
+        self.name = func.__name__
+        return self
+
+    def __get__(self, obj, type=None):
+        tl = getattr(obj, self.tl_attr)
+        try:
+            value = getattr(tl, self.name)
+        except AttributeError:
+            value = self.func(obj)
+            setattr(tl, self.name, value)
+        return value
+
+class DataStore(object):
+    """Manages a connections to Mongo, with seprate connections per thread."""
+
+    def __init__(self, master='mongo://localhost:27017/gutenberg', slave=None,
+                 connect_retry=10):
+        # self._tl_value = ThreadLocal()
+        self._conn = None
+        self._lock = Lock()
+        self._connect_retry = connect_retry
+        self.configure(master, slave)
+
+    def __repr__(self):
+        return 'DataStore(master=%r, slave=%r)' % (
+            self.master_args, self.slave_args)
+
+    def configure(self, master='mongo://localhost:27017/gutenberg', slave=None):
+        log.disabled = 0 # @%#$@ logging fileconfig disables our logger
+        if isinstance(master, basestring):
+            master = [ master ]
+        if slave is None: slave = []
+        assert master, 'You MUST supply at least one master mongo connection'
+        self.master_args = [ parse_uri(s) for s in master if s ]
+        self.slave_args = [ parse_uri(s) for s in slave if s ]
+        if len(self.master_args) > 2:
+            log.warning(
+                'Only two masters are supported at present, you specified %r',
+                master)
+            self.master_args = self.master_args[:2]
+        if len(self.master_args) > 1 and self.slave_args:
+            log.warning(
+                'Master/slave is not supported with replica pairs')
+            self.slave_Args = []
+        self.database = (self.master_args+self.slave_args)[0]['path'][1:]
+        for a in self.master_args + self.slave_args:
+            assert a['path'] == '/' + self.database, \
+                "All connections MUST use the same database"
+
+    @property
+    def conn(self):
+        for attempt in xrange(self._connect_retry+1):
+            if self._conn is not None: break
+            with self._lock:
+                if self._connect() is None:
+                    time.sleep(1)
+        return self._conn
+
+    def _connect(self):
+        self._conn = None
+        try:
+            if len(self.master_args) == 2:
+                self._conn = Connection.paired(
+                    (str(self.master_args[0]['host']), int(self.master_args[0]['port'])),
+                    (str(self.master_args[1]['host']), int(self.master_args[1]['port'])),
+                    pool_size=16)
+            else:
+                if self.master_args:
+                    try:
+                        master = Connection(str(self.master_args[0]['host']), int(self.master_args[0]['port']),
+                                            pool_size=8)
+                    except:
+                        if self.slave_args:
+                            log.exception('Cannot connect to master: %s will use slave: %s' % (self.master_args, self.slave_args))
+                            # and continue... to use the slave only
+                            master = None
+                        else:
+                            raise
+                else:
+                    log.info('No master connection specified, using slaves only: %s' % self.slave_args)
+                    master = None
+
+                if self.slave_args:
+                    slave = [ Connection(str(a['host']), int(a['port']), pool_size=16, slave_okay=True)
+                               for a in self.slave_args ]
+                    if master:
+                        self._conn = MasterSlaveConnection(master, slave)
+                    else:
+                        self._conn = slave[0]
+
+                else:
+                    self._conn = master
+        except:
+            log.exception('Cannot connect to %s %s' % (self.master_args, self.slave_args))
+        else:
+            #log.info('Connected to %s %s' % (self.master_args, self.slave_args))
+            pass
+        return self._conn
+
+    @property
+    def db(self):
+        return getattr(self.conn, self.database, None)