Spaces:
Sleeping
Sleeping
File size: 8,488 Bytes
bb3ee41 bfe0e24 bb3ee41 bfe0e24 bb3ee41 bfe0e24 bb3ee41 bfe0e24 bb3ee41 bfe0e24 bb3ee41 bfe0e24 bb3ee41 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 | """Working memory for reasoning and scratch space with LRU eviction."""
from __future__ import annotations
import asyncio
from collections import OrderedDict
from datetime import datetime, timezone
from typing import Any
from pydantic import BaseModel, Field
def _utc_now() -> datetime:
"""Return current UTC datetime."""
return datetime.now(timezone.utc)
class WorkingMemoryItem(BaseModel):
"""A single item in working memory."""
id: str
content: Any
priority: float = 0.0
created_at: datetime = Field(default_factory=_utc_now)
last_accessed: datetime = Field(default_factory=_utc_now)
access_count: int = 0
metadata: dict[str, Any] = Field(default_factory=dict)
model_config = {"arbitrary_types_allowed": True}
class WorkingMemory:
"""
Working memory for reasoning and scratch computations.
This memory layer provides a limited-capacity buffer with LRU (Least Recently Used)
eviction policy. It's designed for temporary reasoning steps, intermediate results,
and scratch space during agent deliberation.
Attributes:
capacity: Maximum number of items in working memory.
_items: Internal LRU-ordered storage.
"""
def __init__(self, capacity: int = 20) -> None:
"""
Initialize working memory.
Args:
capacity: Maximum number of items to store. Defaults to 20.
"""
self.capacity = capacity
self._items: OrderedDict[str, WorkingMemoryItem] = OrderedDict()
self._counter = 0
self._lock = asyncio.Lock()
@property
def size(self) -> int:
"""Get current number of items in memory."""
return len(self._items)
@property
def is_full(self) -> bool:
"""Check if memory is at capacity."""
return len(self._items) >= self.capacity
async def push(
self,
content: Any,
item_id: str | None = None,
priority: float = 0.0,
metadata: dict[str, Any] | None = None,
) -> WorkingMemoryItem:
"""
Push a new item into working memory.
If capacity is reached, the least recently used item is evicted.
Args:
content: The content to store.
item_id: Optional custom ID. Auto-generated if not provided.
priority: Priority score for potential prioritized eviction.
metadata: Optional metadata dictionary.
Returns:
The created working memory item.
"""
async with self._lock:
# Generate ID if not provided
if item_id is None:
self._counter += 1
item_id = f"wm_{self._counter}"
now = datetime.now(timezone.utc)
# Check if item already exists (update it)
if item_id in self._items:
item = self._items[item_id]
item.content = content
item.last_accessed = now
item.access_count += 1
if metadata:
item.metadata.update(metadata)
if priority != 0.0:
item.priority = priority
# Move to end (most recent)
self._items.move_to_end(item_id)
return item
# Evict LRU item if at capacity
if len(self._items) >= self.capacity:
self._evict_lru()
# Create new item
item = WorkingMemoryItem(
id=item_id,
content=content,
priority=priority,
created_at=now,
last_accessed=now,
metadata=metadata or {},
)
self._items[item_id] = item
return item
def _evict_lru(self) -> WorkingMemoryItem | None:
"""
Evict the least recently used item.
Returns:
The evicted item, or None if memory was empty.
"""
if not self._items:
return None
# Pop first item (least recently used)
_, item = self._items.popitem(last=False)
return item
async def pop(self) -> WorkingMemoryItem | None:
"""
Remove and return the most recently used item.
Returns:
The most recent item, or None if memory is empty.
"""
async with self._lock:
if not self._items:
return None
_, item = self._items.popitem(last=True)
return item
async def pop_by_id(self, item_id: str) -> WorkingMemoryItem | None:
"""
Remove and return an item by its ID.
Args:
item_id: The ID of the item to remove.
Returns:
The removed item, or None if not found.
"""
async with self._lock:
return self._items.pop(item_id, None)
async def peek(self) -> WorkingMemoryItem | None:
"""
Return the most recently used item without removing it.
Returns:
The most recent item, or None if memory is empty.
"""
async with self._lock:
if not self._items:
return None
# Get last item
item_id = next(reversed(self._items))
item = self._items[item_id]
item.last_accessed = datetime.now(timezone.utc)
item.access_count += 1
return item
async def peek_by_id(self, item_id: str) -> WorkingMemoryItem | None:
"""
Return an item by ID without removing it.
Args:
item_id: The ID of the item to peek.
Returns:
The item, or None if not found.
"""
async with self._lock:
item = self._items.get(item_id)
if item:
item.last_accessed = datetime.now(timezone.utc)
item.access_count += 1
# Move to end (mark as recently accessed)
self._items.move_to_end(item_id)
return item
async def get_all(self) -> list[WorkingMemoryItem]:
"""
Get all items in memory, ordered by recency.
Returns:
List of items from least to most recent.
"""
async with self._lock:
return list(self._items.values())
async def get_recent(self, n: int = 5) -> list[WorkingMemoryItem]:
"""
Get the N most recently accessed items.
Args:
n: Number of items to return.
Returns:
List of most recent items.
"""
async with self._lock:
items = list(self._items.values())
return items[-n:] if n < len(items) else items
async def clear(self) -> int:
"""
Clear all items from working memory.
Returns:
Number of items that were cleared.
"""
async with self._lock:
count = len(self._items)
self._items.clear()
self._counter = 0
return count
async def search(self, predicate: Any) -> list[WorkingMemoryItem]:
"""
Search items using a predicate function.
Args:
predicate: Callable that takes a WorkingMemoryItem and returns bool.
Returns:
List of matching items.
"""
async with self._lock:
return [item for item in self._items.values() if predicate(item)]
async def update_priority(self, item_id: str, priority: float) -> bool:
"""
Update the priority of an item.
Args:
item_id: ID of the item to update.
priority: New priority value.
Returns:
True if item was found and updated, False otherwise.
"""
async with self._lock:
if item_id in self._items:
self._items[item_id].priority = priority
return True
return False
async def get_stats(self) -> dict[str, Any]:
"""
Get statistics about working memory.
Returns:
Dictionary with memory statistics.
"""
async with self._lock:
return {
"size": len(self._items),
"capacity": self.capacity,
"is_full": len(self._items) >= self.capacity,
"utilization": len(self._items) / self.capacity if self.capacity > 0 else 0,
"item_ids": list(self._items.keys()),
}
|