Add cache key helper functions and tests

tenant_schemas/cache.py

@@ -0,0 +1,20 @@
+from django.db import connection
+
+
+def make_key(key, key_prefix, version):
+    """
+    Tenant aware function to generate a cache key.
+
+    Constructs the key used by all other methods. Prepends the tenant
+    `schema_name` and `key_prefix'.
+    """
+    return '%s:%s:%s:%s' % (connection.schema_name, key_prefix, version, key)
+
+
+def reverse_key(key):
+    """
+    Tenant aware function to reverse a cache key.
+
+    Required for django-redis REVERSE_KEY_FUNCTION setting.
+    """
+    return key.split(':', 3)[3]

tenant_schemas/tests/__init__.py

@@ -1,2 +1,3 @@
 from test_routes import *
 from test_tenants import *
+from test_cache import *

tenant_schemas/tests/test_cache.py

@@ -0,0 +1,13 @@
+from tenant_schemas.cache import make_key, reverse_key
+from tenant_schemas.test.cases import TenantTestCase
+
+
+class CacheHelperTestCase(TenantTestCase):
+    def test_make_key(self):
+        key = make_key(key='foo', key_prefix='', version=1)
+        tenant_prefix = key.split(':')[0]
+        self.assertEqual(self.tenant.schema_name, tenant_prefix)
+
+    def test_reverse_key(self):
+        key = 'foo'
+        self.assertEqual(key, reverse_key(make_key(key=key, key_prefix='', version=1)))