| """
|
| Task: T010
|
| Spec: 010-ai-chatbot/spec.md - Message Model
|
|
|
| Message model for storing user and AI chatbot conversation messages.
|
| Each message belongs to exactly one user and one conversation for proper isolation.
|
| """
|
|
|
| from sqlmodel import SQLModel, Field, Relationship
|
| from datetime import datetime, timezone
|
| from typing import Optional, TYPE_CHECKING, Literal, Dict, Any
|
| import uuid
|
| import enum
|
|
|
| if TYPE_CHECKING:
|
| from app.models.user import User
|
| from app.models.conversation import Conversation
|
|
|
|
|
| class MessageRole(str, enum.Enum):
|
| """Message roles for conversation participants."""
|
| USER = "user"
|
| ASSISTANT = "assistant"
|
|
|
|
|
| class Message(SQLModel, table=True):
|
| """
|
| Message model representing individual chat messages in a conversation.
|
|
|
| Each message belongs to exactly one user and one conversation (enforced by foreign keys).
|
| Messages are isolated by user_id for multi-tenant data separation.
|
| """
|
| __tablename__ = "messages"
|
|
|
| id: str = Field(
|
| default_factory=lambda: str(uuid.uuid4()),
|
| primary_key=True,
|
| description="Unique message identifier (UUID)"
|
| )
|
| user_id: str = Field(
|
| foreign_key="users.id",
|
| nullable=False,
|
| index=True,
|
| description="Owner user ID (foreign key to users table, indexed for fast queries)"
|
| )
|
| conversation_id: str = Field(
|
| foreign_key="conversations.id",
|
| nullable=False,
|
| index=True,
|
| description="Associated conversation ID (foreign key to conversations table, indexed for fast queries)"
|
| )
|
| role: MessageRole = Field(
|
| nullable=False,
|
| description="Sender role (user or assistant)"
|
| )
|
| content: str = Field(
|
| max_length=10000,
|
| nullable=False,
|
| description="Message content (required, max 10000 characters)"
|
| )
|
| tool_calls: Optional[str] = Field(
|
| default=None,
|
| description="MCP tool calls made during this message (JSON string)"
|
| )
|
| tool_responses: Optional[str] = Field(
|
| default=None,
|
| description="Responses from MCP tools (JSON string)"
|
| )
|
| created_at: datetime = Field(
|
| default_factory=lambda: datetime.now(timezone.utc).replace(tzinfo=None),
|
| description="Message creation timestamp (UTC)"
|
| )
|
|
|
|
|
| user: Optional["User"] = Relationship(back_populates="messages")
|
| conversation: Optional["Conversation"] = Relationship(back_populates="messages") |
