Make StrictRedis.from_url work

Closes #19.

birdisle/redis.py

@@ -92,6 +92,20 @@ def __init__(self, server=None, host='localhost', port=6379,
             ssl_check_hostname, max_connections, single_connection_client,
             health_check_interval, client_name, username)
 
+    @classmethod
+    def from_url(cls, url, db=None, **kwargs):
+        server = kwargs.pop('server', None)
+        if server is None:
+            server = birdisle.Server()
+        self = super().from_url(url, db, **kwargs)
+        self.connection_pool.connection_class = LocalSocketConnection
+        self.connection_pool.connection_kwargs['server'] = server
+        # When url is a unix:// URL, connection_kwargs will include 'path',
+        # but LocalSocketConnection does not expect that (because the base
+        # class does not).
+        self.connection_pool.connection_kwargs.pop('path', None)
+        return self
+
 
 class StrictRedis(RedisMixin, redis.StrictRedis):
     """Replacement for :class:`redis.StrictRedis` that connects to a birdisle server.

tests/test_birdisle.py

@@ -20,7 +20,7 @@ def server():
 @pytest.fixture
 def r(server):
     redis = birdisle.redis.StrictRedis(server=server)
-    yield redis
+    return redis
 
 
 @pytest.fixture
@@ -166,6 +166,16 @@ def test_shared_server(server):
     assert b.get('foo') == b'bar'
 
 
+@pytest.mark.parametrize('url', ['unix:///some/path/?db=7', 'redis://host.invalid:12345/7'])
+def test_from_url(server, url):
+    r = birdisle.redis.StrictRedis.from_url(url, server=server)
+    r.set('hello', 'world')
+    assert r.get('hello') == b'world'
+    # Check that we're using DB 7 (more specifically, not 0) by swapping it away
+    r.swapdb(7, 8)
+    assert r.get('hello') is None
+
+
 def test_signals(r, profile_timer):
     """Test that signal delivery doesn't interfere with birdisle"""
     def handler(signum, frame):