feat: add happened at and extra fields to memory item (#262)

Author: evan-ak

src/memu/database/models.py

@@ -2,7 +2,7 @@
 
 import uuid
 from datetime import datetime
-from typing import Literal
+from typing import Any, Literal
 
 import pendulum
 from pydantic import BaseModel, ConfigDict, Field
@@ -31,6 +31,8 @@ class MemoryItem(BaseRecord):
     memory_type: MemoryType
     summary: str
     embedding: list[float] | None = None
+    happened_at: datetime | None = None
+    extra: dict[str, Any] = {}
 
 
 class MemoryCategory(BaseRecord):

src/memu/database/postgres/models.py

@@ -14,6 +14,7 @@
 
 from pydantic import BaseModel
 from sqlalchemy import ForeignKey, MetaData, String, Text
+from sqlalchemy.dialects.postgresql import JSONB
 from sqlmodel import Column, DateTime, Field, Index, SQLModel, func
 
 from memu.database.models import CategoryItem, MemoryCategory, MemoryItem, MemoryType, Resource
@@ -55,6 +56,8 @@ class MemoryItemModel(BaseModelMixin, MemoryItem):
     memory_type: MemoryType = Field(sa_column=Column(String, nullable=False))
     summary: str = Field(sa_column=Column(Text, nullable=False))
     embedding: list[float] | None = Field(default=None, sa_column=Column(Vector(), nullable=True))
+    happened_at: datetime | None = Field(default=None, sa_column=Column(DateTime, nullable=True))
+    extra: dict[str, Any] = Field(default={}, sa_column=Column(JSONB, nullable=True))
 
 
 class MemoryCategoryModel(BaseModelMixin, MemoryCategory):

src/memu/database/sqlite/models.py

@@ -10,7 +10,7 @@
 
 import pendulum
 from pydantic import BaseModel
-from sqlalchemy import MetaData, String, Text
+from sqlalchemy import JSON, MetaData, String, Text
 from sqlmodel import Column, DateTime, Field, Index, SQLModel, func
 
 from memu.database.models import CategoryItem, MemoryCategory, MemoryItem, MemoryType, Resource
@@ -83,6 +83,8 @@ class SQLiteMemoryItemModel(SQLiteBaseModelMixin, MemoryItem):
     summary: str = Field(sa_column=Column(Text, nullable=False))
     # Store embedding as JSON string since SQLite doesn't have native vector type
     embedding_json: str | None = Field(default=None, sa_column=Column(Text, nullable=True))
+    happened_at: datetime | None = Field(default=None, sa_column=Column(DateTime, nullable=True))
+    extra: dict[str, Any] = Field(default={}, sa_column=Column(JSON, nullable=True))
 
     @property
     def embedding(self) -> list[float] | None: