chore: import upstream snapshot with attribution

runtime/node/agent/memory/blackboard_memory.py

@@ -0,0 +1,99 @@
+"""Lightweight append-only Blackboard memory implementation."""
+
+import json
+import os
+import time
+import uuid
+from typing import List
+
+from entity.configs import MemoryStoreConfig
+from entity.configs.node.memory import BlackboardMemoryConfig
+from runtime.node.agent.memory.memory_base import (
+    MemoryBase,
+    MemoryContentSnapshot,
+    MemoryItem,
+    MemoryWritePayload,
+)
+
+
+class BlackboardMemory(MemoryBase):
+    """Simple append-only memory: save raw outputs, retrieve by recency."""
+
+    def __init__(self, store: MemoryStoreConfig):
+        config = store.as_config(BlackboardMemoryConfig)
+        if not config:
+            raise ValueError("BlackboardMemory requires a blackboard memory store configuration")
+        super().__init__(store)
+        self.config = config
+        self.memory_path = config.memory_path
+        self.max_items = config.max_items
+
+    # -------- Persistence --------
+    def load(self) -> None:
+        if not self.memory_path or not os.path.exists(self.memory_path):
+            self.contents = []
+            return
+
+        try:
+            with open(self.memory_path, "r", encoding="utf-8") as file:
+                data = json.load(file)
+            contents: List[MemoryItem] = []
+            for raw in data:
+                try:
+                    contents.append(MemoryItem.from_dict(raw))
+                except Exception:
+                    continue
+            self.contents = contents
+        except Exception:
+            # Corrupted file -> reset to empty to avoid blocking execution
+            self.contents = []
+
+    def save(self) -> None:
+        if not self.memory_path:
+            return
+
+        os.makedirs(os.path.dirname(self.memory_path), exist_ok=True)
+        payload = [item.to_dict() for item in self.contents[-self.max_items :]]
+        with open(self.memory_path, "w", encoding="utf-8") as file:
+            json.dump(payload, file, ensure_ascii=False, indent=2)
+
+    # -------- Memory operations --------
+    def retrieve(
+        self,
+        agent_role: str,
+        query: MemoryContentSnapshot,
+        top_k: int,
+        similarity_threshold: float,
+    ) -> List[MemoryItem]:
+        if not self.contents:
+            return []
+
+        if top_k <= 0 or top_k >= len(self.contents):
+            return list(self.contents)
+
+        return list(self.contents[-top_k:])
+
+    def update(self, payload: MemoryWritePayload) -> None:
+        snapshot = payload.output_snapshot or payload.input_snapshot
+        content = (snapshot.text if snapshot else payload.inputs_text or "").strip()
+        if not content:
+            return
+
+        metadata = {
+            "agent_role": payload.agent_role,
+            "input_preview": (payload.inputs_text or "")[:200],
+            "attachments": snapshot.attachment_overview() if snapshot else [],
+        }
+
+        memory_item = MemoryItem(
+            id=f"bb_{uuid.uuid4().hex}",
+            content_summary=content,
+            metadata=metadata,
+            timestamp=time.time(),
+            input_snapshot=payload.input_snapshot,
+            output_snapshot=payload.output_snapshot,
+        )
+
+        self.contents.append(memory_item)
+        if len(self.contents) > self.max_items:
+            self.contents = self.contents[-self.max_items :]