making either store or config

pydantic_redis/_shared/store.py

@@ -6,7 +6,7 @@
 from pydantic.fields import ModelPrivateAttr
 from redis import Redis
 from redis.asyncio import Redis as AioRedis
-from pydantic import ConfigDict, BaseModel
+from pydantic import ConfigDict, BaseModel, model_validator
 from redis.commands.core import Script, AsyncScript
 
 from ..config import RedisConfig
@@ -32,7 +32,7 @@ class AbstractStore(BaseModel):
     """
 
     name: str
-    redis_config: RedisConfig
+    redis_config: Optional[RedisConfig] = None
     redis_store: Optional[Union[Redis, AioRedis]] = None
     life_span_in_seconds: Optional[int] = None
     select_all_fields_for_all_ids_script: Optional[Union[AsyncScript, Script]] = None
@@ -51,11 +51,29 @@ class AbstractStore(BaseModel):
     def __init__(
         self,
         name: str,
-        redis_config: RedisConfig,
+        redis_config: Optional[RedisConfig] = None,
         redis_store: Optional[Union[Redis, AioRedis]] = None,
         life_span_in_seconds: Optional[int] = None,
         **data: Any,
     ):
+        """
+        A store provides all functionality required to quickly persist and retrieve
+        pydantic objects into and from a Redis store.
+
+        This store will accept the configuration (in the form of a `RedisConfig`, and
+        create a new Redis instance according to that configuration. Alternatively,
+        one can pass an existing Redis instance to be used. One can only pass one ot
+        these.
+
+        :param name: The name of the store.
+        :param redis_config: A Redis configuration object. This will be used to create a
+        new Redis instance, using the parameters configured.
+        :param redis_store: An existing Redis instance to use. Can only be passed when no
+        `redis_config` is passed.
+        :param life_span_in_seconds: The default lifespan in seconds that the store will use
+        :param data: an other keyword argument that will be passed to the constructor of
+        the object
+        """
         super().__init__(
             name=name,
             redis_config=redis_config,
@@ -64,9 +82,18 @@ def __init__(
             **data,
         )
 
-        self.redis_store = self._connect_to_redis()
+        # because of validator we can safely assume either `redis_store` is passed or `redis_config`
+        if self.redis_store is None:
+            self.redis_store = self._connect_to_redis()
         self._register_lua_scripts()
 
+    @model_validator(mode='after')
+    def _config_or_redis(self):
+        if (self.redis_config is None) and (self.redis_store is None):
+            raise ValueError("Must provide one of redis_config or redis_store")
+        if (self.redis_config is not None) and (self.redis_store is not None):
+            raise ValueError("Cannot provide both redis_config and redis_store")
+
     def _connect_to_redis(self) -> Union[Redis, AioRedis]:
         """Connects the store to redis.
 

test/test_redis_or_config.py

@@ -0,0 +1,44 @@
+import pytest
+import redislite
+from redis.client import Redis
+
+from pydantic_redis import Store, RedisConfig
+
+
+def test_need_config_or_redis():
+    with pytest.raises(ValueError):
+        _ = Store(name="no-redis-or-config")
+
+
+def test_cannot_provide_both(unused_tcp_port: int):
+    redis = redislite.Redis(host="localhost", port=unused_tcp_port)
+    config = RedisConfig(host="localhost", port=unused_tcp_port)
+
+    with pytest.raises(ValueError):
+        _ = Store(
+            name="redis-or-config",
+            redis_config=config,
+            redis_store=redis,
+        )
+
+def test_config_creates_new():
+    store = Store(
+        name="redis-or-config",
+        redis_config=RedisConfig(
+            host="localhost",
+            port=6379,
+            db=0,
+        ),
+    )
+    assert store.redis_store is not None
+    assert isinstance(store.redis_store, Redis)
+
+
+def test_store_creates_new(unused_tcp_port: int):
+    redis = redislite.Redis(host="localhost", port=unused_tcp_port)
+    pydantic_redis_store = Store(
+        name="redis-or-config",
+        redis_store=redis,
+    )
+
+    assert pydantic_redis_store.redis_store == redis