Adds MAX_CONNECTIONS option for the connection pool.

redis_cache/cache.py

@@ -47,8 +47,8 @@ class CacheConnectionPool(object):
 
     def get_connection_pool(self, host='127.0.0.1', port=6379, db=1,
                             password=None, parser_class=None,
-                            unix_socket_path=None):
-        connection_identifier = (host, port, db, parser_class, unix_socket_path)
+                            unix_socket_path=None, max_connections=None):
+        connection_identifier = (host, port, db, parser_class, unix_socket_path, max_connections)
         if not self._connection_pools.get(connection_identifier):
             connection_class = (
                 unix_socket_path and UnixDomainSocketConnection or Connection
@@ -58,6 +58,7 @@ class CacheConnectionPool(object):
                 'password': password,
                 'connection_class': connection_class,
                 'parser_class': parser_class,
+                'max_connections': max_connections,
             }
             if unix_socket_path is None:
                 kwargs.update({
@@ -101,8 +102,10 @@ class CacheClass(BaseCache):
             'port': port,
             'unix_socket_path': unix_socket_path,
         }
+
         connection_pool = pool.get_connection_pool(
             parser_class=self.parser_class,
+            max_connections=self.max_connections,
             **kwargs
         )
         self._client = redis.Redis(
@@ -122,6 +125,10 @@ class CacheClass(BaseCache):
     def options(self):
         return self.params.get('OPTIONS', {})
 
+    @property
+    def max_connections(self):
+        return self.options.get('MAX_CONNECTIONS', None)
+
     @property
     def db(self):
         _db = self.params.get('db', self.options.get('DB', 1))

tcptests.py

@@ -21,7 +21,8 @@ cache_settings = {
             'OPTIONS': {
                 'DB': 15,
                 'PASSWORD': 'yadayada',
-                'PARSER_CLASS': 'redis.connection.HiredisParser'
+                'PARSER_CLASS': 'redis.connection.HiredisParser',
+                'MAX_CONNECTIONS': 2,
             },
         },
     },

tests/settings.py

@@ -17,6 +17,7 @@ CACHES = {
         'OPTIONS': {  # optional
             'DB': 15,
             'PASSWORD': 'yadayada',
+            'MAX_CONNECTIONS': 2,
         },
     },
 }

tests/testapp/tests.py

@@ -10,17 +10,21 @@ from django import VERSION
 from django.core.cache import get_cache
 from django.test import TestCase
 from .models import Poll, expensive_calculation
-from redis_cache.cache import RedisCache, ImproperlyConfigured, pool
+import redis
 from redis.connection import UnixDomainSocketConnection
+from redis_cache.cache import RedisCache, ImproperlyConfigured, pool
 
 
 # functions/classes for complex data type tests
 def f():
     return 42
+
+
 class C:
     def m(n):
         return 24
 
+
 class RedisCacheTests(TestCase):
     """
     A common set of tests derived from Django's own cache tests
@@ -349,11 +353,11 @@ class RedisCacheTests(TestCase):
 
     def test_multiple_connection_pool_connections(self):
         pool._connection_pools = {}
-        c1 = get_cache('redis_cache.cache://127.0.0.1:6379?db=15')
+        get_cache('redis_cache.cache://127.0.0.1:6379?db=15')
         self.assertEqual(len(pool._connection_pools), 1)
-        c2 = get_cache('redis_cache.cache://127.0.0.1:6379?db=14')
+        get_cache('redis_cache.cache://127.0.0.1:6379?db=14')
         self.assertEqual(len(pool._connection_pools), 2)
-        c3 = get_cache('redis_cache.cache://127.0.0.1:6379?db=15')
+        get_cache('redis_cache.cache://127.0.0.1:6379?db=15')
         self.assertEqual(len(pool._connection_pools), 2)
 
     def test_setting_string_integer_retrieves_string(self):
@@ -366,8 +370,31 @@ class RedisCacheTests(TestCase):
         self.assertTrue(self.cache.set("bool_f", False))
         self.assertEqual(self.cache.get("bool_f"), False)
 
+    def test_max_connections(self):
+        pool._connection_pools = {}
+        cache = get_cache('default')
+
+        def noop(*args, **kwargs):
+            pass
+
+        release = cache._client.connection_pool.release
+        cache._client.connection_pool.release = noop
+        self.assertEqual(cache._client.connection_pool.max_connections, 2)
+
+        cache.set('a', 'a')
+        self.assertEqual(cache._client.connection_pool._created_connections, 1)
+
+        cache.set('a', 'a')
+        self.assertEqual(cache._client.connection_pool._created_connections, 2)
+
+        with self.assertRaises(redis.ConnectionError):
+            cache.set('a', 'a')
 
+        self.assertEqual(cache._client.connection_pool._created_connections, 2)
+        cache._client.connection_pool.release = release
+        cache._client.connection_pool.max_connections = 2**31
 
 
 if __name__ == '__main__':
+    import unittest
     unittest.main()