Add model constraints and safe defaults

Author: Saahi30

Backend/app/models/models.py

@@ -10,8 +10,12 @@
     DateTime,
     Boolean,
     TIMESTAMP,
+    UniqueConstraint,
+    CheckConstraint,
+    Index,
+    Enum,
 )
-from sqlalchemy.orm import relationship
+from sqlalchemy.orm import relationship, backref
 from datetime import datetime, timezone
 from app.db.db import Base
 import uuid
@@ -167,8 +171,10 @@ class SponsorshipPayment(Base):
 # ============================================================================
 
 # Brand Profile Table (Extended brand information)
-class BrandProfile(Base):
     __tablename__ = "brand_profiles"
+    __table_args__ = (
+        UniqueConstraint("user_id", name="uq_brand_profiles_user_id"),
+    )
 
     id = Column(String, primary_key=True, default=generate_uuid)
     user_id = Column(String, ForeignKey("users.id"), nullable=False)
@@ -182,7 +188,7 @@ class BrandProfile(Base):
     )
 
     # Relationships
-    user = relationship("User", backref="brand_profile")
+    user = relationship("User", backref=backref("brand_profile", uselist=False))
 
 
 # Campaign Metrics Table (Performance tracking)
@@ -205,15 +211,27 @@ class CampaignMetrics(Base):
 
 
 # Contracts Table (Contract management)
+# Contracts Table (Contract management)
+from enum import Enum as PyEnum
+
+class ContractStatus(PyEnum):
+    DRAFT = "draft"
+    SIGNED = "signed"
+    COMPLETED = "completed"
+    CANCELLED = "cancelled"
+
 class Contract(Base):
     __tablename__ = "contracts"
+    __table_args__ = (
+        UniqueConstraint("sponsorship_id", "creator_id", name="uq_sponsorship_creator_contract"),
+    )
 
     id = Column(String, primary_key=True, default=generate_uuid)
-    sponsorship_id = Column(String, ForeignKey("sponsorships.id"), nullable=False)
-    creator_id = Column(String, ForeignKey("users.id"), nullable=False)
-    brand_id = Column(String, ForeignKey("users.id"), nullable=False)
+    sponsorship_id = Column(String, ForeignKey("sponsorships.id", ondelete="CASCADE"), nullable=False)
+    creator_id = Column(String, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
+    brand_id = Column(String, ForeignKey("users.id", ondelete="RESTRICT"), nullable=False)
     contract_url = Column(String, nullable=True)
-    status = Column(String, default="draft")  # draft, signed, completed, cancelled
+    status = Column(Enum(ContractStatus), default=ContractStatus.DRAFT, nullable=False)
     created_at = Column(
         DateTime(timezone=True), default=lambda: datetime.now(timezone.utc)
     )
@@ -227,6 +245,11 @@ class Contract(Base):
 # Creator Matches Table (AI-powered matching)
 class CreatorMatch(Base):
     __tablename__ = "creator_matches"
+    __table_args__ = (
+        UniqueConstraint("brand_id", "creator_id", name="uq_brand_creator"),
+        CheckConstraint("match_score >= 0 AND match_score <= 1", name="ck_match_score_bounds"),
+        Index("ix_brand_creator", "brand_id", "creator_id"),
+    )
 
     id = Column(String, primary_key=True, default=generate_uuid)
     brand_id = Column(String, ForeignKey("users.id"), nullable=False)

Backend/app/routes/ai_query.py

@@ -1,6 +1,6 @@
 from fastapi import APIRouter, HTTPException, Query, Depends, Request
 from typing import Dict, Any, Optional
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
 import logging
 from ..services.ai_router import ai_router
 from ..services.redis_client import get_session_state, save_session_state
@@ -22,7 +22,7 @@ class AIQueryRequest(BaseModel):
 class AIQueryResponse(BaseModel):
     intent: str
     route: Optional[str] = None
-    parameters: Dict[str, Any] = {}
+    parameters: Dict[str, Any] = Field(default_factory=dict)
     follow_up_needed: bool = False
     follow_up_question: Optional[str] = None
     explanation: str
@@ -89,7 +89,7 @@ def get_api_args(intent, params):
         missing_params = []
         if intent in intent_param_map:
             for param in intent_param_map[intent]["required"]:
-                if not params.get(param):
+                if params.get(param) is None:
                     all_params_present = False
                     missing_params.append(param)