added routes table

Author: eddywang4340

backend/python/app/models/routes.py

@@ -0,0 +1,61 @@
+from uuid import UUID, uuid4
+
+from sqlmodel import Field, SQLModel, Relationship
+
+from .base import BaseModel
+
+
+class RouteBase(SQLModel):
+    """Shared fields between table and API models"""
+
+    route_group_id: UUID | None = Field(
+        foreign_key = "route_groups.id"
+    )
+    name: str = Field(default="", min_length=1, max_length=255) # can change this later
+    notes: str = Field(default="", max_length=1000) # can change this later
+    length: float = Field(ge=0.0)  # in km, must be non-negative
+
+
+class Route(RouteBase, BaseModel, table=True):
+    """Database table model for Routes
+    
+    Note: Routes are immutable once created
+    """
+
+    __tablename__ = "routes"
+
+    route_id: UUID = Field(
+        default=uuid4,
+        primary_key=True,
+        nullable=False
+    )
+
+    # Relationship to route stops
+    route_stops: list["RouteStop"] = Relationship(
+        back_populates="route",
+        sa_relationship_kwargs={"cascade": "all, delete-orphan"}
+    )
+
+
+class RouteCreate(RouteBase):
+    """Create request model"""
+
+    pass
+
+
+class RouteRead(RouteBase):
+    """Read response model"""
+
+    route_id: UUID
+
+
+class RouteUpdate(SQLModel):
+    """Update request model - all optional
+    
+    Note: Routes are meant to be immutable, but this allows updates if needed
+    """
+
+    route_group_id: UUID | None = None
+    name: str | None = None
+    notes: str | None = None
+    length: float | None = None