initial commit

venv/Lib/site-packages/langgraph/cache/redis/__init__.py

@@ -0,0 +1,144 @@
+from __future__ import annotations
+
+from collections.abc import Mapping, Sequence
+from typing import Any
+
+from langgraph.cache.base import BaseCache, FullKey, Namespace, ValueT
+from langgraph.checkpoint.serde.base import SerializerProtocol
+
+
+class RedisCache(BaseCache[ValueT]):
+    """Redis-based cache implementation with TTL support."""
+
+    def __init__(
+        self,
+        redis: Any,
+        *,
+        serde: SerializerProtocol | None = None,
+        prefix: str = "langgraph:cache:",
+    ) -> None:
+        """Initialize the cache with a Redis client.
+
+        Args:
+            redis: Redis client instance (sync or async)
+            serde: Serializer to use for values
+            prefix: Key prefix for all cached values
+        """
+        super().__init__(serde=serde)
+        self.redis = redis
+        self.prefix = prefix
+
+    def _make_key(self, ns: Namespace, key: str) -> str:
+        """Create a Redis key from namespace and key."""
+        ns_str = ":".join(ns) if ns else ""
+        return f"{self.prefix}{ns_str}:{key}" if ns_str else f"{self.prefix}{key}"
+
+    def _parse_key(self, redis_key: str) -> tuple[Namespace, str]:
+        """Parse a Redis key back to namespace and key."""
+        if not redis_key.startswith(self.prefix):
+            raise ValueError(
+                f"Key {redis_key} does not start with prefix {self.prefix}"
+            )
+
+        remaining = redis_key[len(self.prefix) :]
+        if ":" in remaining:
+            parts = remaining.split(":")
+            key = parts[-1]
+            ns_parts = parts[:-1]
+            return (tuple(ns_parts), key)
+        else:
+            return (tuple(), remaining)
+
+    def get(self, keys: Sequence[FullKey]) -> dict[FullKey, ValueT]:
+        """Get the cached values for the given keys."""
+        if not keys:
+            return {}
+
+        # Build Redis keys
+        redis_keys = [self._make_key(ns, key) for ns, key in keys]
+
+        # Get values from Redis using MGET
+        try:
+            raw_values = self.redis.mget(redis_keys)
+        except Exception:
+            # If Redis is unavailable, return empty dict
+            return {}
+
+        values: dict[FullKey, ValueT] = {}
+        for i, raw_value in enumerate(raw_values):
+            if raw_value is not None:
+                try:
+                    # Deserialize the value
+                    encoding, data = raw_value.split(b":", 1)
+                    values[keys[i]] = self.serde.loads_typed((encoding.decode(), data))
+                except Exception:
+                    # Skip corrupted entries
+                    continue
+
+        return values
+
+    async def aget(self, keys: Sequence[FullKey]) -> dict[FullKey, ValueT]:
+        """Asynchronously get the cached values for the given keys."""
+        return self.get(keys)
+
+    def set(self, mapping: Mapping[FullKey, tuple[ValueT, int | None]]) -> None:
+        """Set the cached values for the given keys and TTLs."""
+        if not mapping:
+            return
+
+        # Use pipeline for efficient batch operations
+        pipe = self.redis.pipeline()
+
+        for (ns, key), (value, ttl) in mapping.items():
+            redis_key = self._make_key(ns, key)
+            encoding, data = self.serde.dumps_typed(value)
+
+            # Store as "encoding:data" format
+            serialized_value = f"{encoding}:".encode() + data
+
+            if ttl is not None:
+                pipe.setex(redis_key, ttl, serialized_value)
+            else:
+                pipe.set(redis_key, serialized_value)
+
+        try:
+            pipe.execute()
+        except Exception:
+            # Silently fail if Redis is unavailable
+            pass
+
+    async def aset(self, mapping: Mapping[FullKey, tuple[ValueT, int | None]]) -> None:
+        """Asynchronously set the cached values for the given keys and TTLs."""
+        self.set(mapping)
+
+    def clear(self, namespaces: Sequence[Namespace] | None = None) -> None:
+        """Delete the cached values for the given namespaces.
+        If no namespaces are provided, clear all cached values."""
+        try:
+            if namespaces is None:
+                # Clear all keys with our prefix
+                pattern = f"{self.prefix}*"
+                keys = self.redis.keys(pattern)
+                if keys:
+                    self.redis.delete(*keys)
+            else:
+                # Clear specific namespaces
+                keys_to_delete = []
+                for ns in namespaces:
+                    ns_str = ":".join(ns) if ns else ""
+                    pattern = (
+                        f"{self.prefix}{ns_str}:*" if ns_str else f"{self.prefix}*"
+                    )
+                    keys = self.redis.keys(pattern)
+                    keys_to_delete.extend(keys)
+
+                if keys_to_delete:
+                    self.redis.delete(*keys_to_delete)
+        except Exception:
+            # Silently fail if Redis is unavailable
+            pass
+
+    async def aclear(self, namespaces: Sequence[Namespace] | None = None) -> None:
+        """Asynchronously delete the cached values for the given namespaces.
+        If no namespaces are provided, clear all cached values."""
+        self.clear(namespaces)