feat: implement member model support for customer seats

CLAUDE.md

@@ -142,6 +142,7 @@ docker compose up -d  # Start PostgreSQL, Redis, Minio
 - Include HTTP status codes in custom exceptions
 - Use dependency injection for database sessions
 - All DB queries should be in the Repository class. Use the right repository class.
+- Always place imports at the top of files, not inside functions or methods.
 
 In most cases, you should never call `session.commit()` directly in business logic. We have established patterns for that: the API backend automatically commits the session at the end of each request, and background workers commit the session at the end of each task. It avoids to have a database in an inconsistent state in case of exceptions. If you have a `session.commit()` in your code, it's likely a mistake. Otherwise, please explicitly document why it's necessary.
 

server/polar/customer_portal/endpoints/customer_seat.py

@@ -168,12 +168,12 @@ async def assign_seat(
         metadata=seat_assign.metadata,
     )
 
-    # Reload seat with customer relationship
+    # Reload seat with customer and member relationships
     seat_repository = CustomerSeatRepository.from_session(session)
     seat_statement = (
         seat_repository.get_base_statement()
         .where(CustomerSeat.id == seat.id)
-        .options(joinedload(CustomerSeat.customer))
+        .options(joinedload(CustomerSeat.customer), joinedload(CustomerSeat.member))
     )
     reloaded_seat = await seat_repository.get_one_or_none(seat_statement)
 

server/polar/customer_seat/endpoints.py

@@ -341,12 +341,22 @@ async def get_claim_info(
     if not organization:
         raise ResourceNotFound("Organization not found")
 
+    # Get customer email with priority: seat.email > seat.member.email > seat.customer.email
+    # This handles both member_model_enabled=True (email on seat) and False (email on customer)
+    customer_email = ""
+    if seat.email:
+        customer_email = seat.email
+    elif seat.member:
+        customer_email = seat.member.email
+    elif seat.customer:
+        customer_email = seat.customer.email
+
     return SeatClaimInfo(
         product_name=product.name,
         product_id=product.id,
         organization_name=organization.name,
         organization_slug=organization.slug,
-        customer_email=seat.customer.email if seat.customer else "",
+        customer_email=customer_email,
         can_claim=seat.status == SeatStatus.pending,
     )
 

server/polar/customer_seat/repository.py

@@ -59,6 +59,59 @@ async def get_by_container_and_customer(
                 container.id, customer_id, options=options
             )
 
+    async def get_by_container_and_email(
+        self,
+        container: SeatContainer,
+        email: str,
+        *,
+        options: Options = (),
+    ) -> CustomerSeat | None:
+        """Get seat by container and email (for member_model_enabled path)."""
+        if isinstance(container, Subscription):
+            return await self.get_by_subscription_and_email(
+                container.id, email, options=options
+            )
+        else:
+            return await self.get_by_order_and_email(
+                container.id, email, options=options
+            )
+
+    async def get_by_subscription_and_email(
+        self,
+        subscription_id: UUID,
+        email: str,
+        *,
+        options: Options = (),
+    ) -> CustomerSeat | None:
+        """Get seat by subscription ID and email."""
+        statement = (
+            select(CustomerSeat)
+            .where(
+                CustomerSeat.subscription_id == subscription_id,
+                func.lower(CustomerSeat.email) == email.lower(),
+            )
+            .options(*options)
+        )
+        return await self.get_one_or_none(statement)
+
+    async def get_by_order_and_email(
+        self,
+        order_id: UUID,
+        email: str,
+        *,
+        options: Options = (),
+    ) -> CustomerSeat | None:
+        """Get seat by order ID and email."""
+        statement = (
+            select(CustomerSeat)
+            .where(
+                CustomerSeat.order_id == order_id,
+                func.lower(CustomerSeat.email) == email.lower(),
+            )
+            .options(*options)
+        )
+        return await self.get_one_or_none(statement)
+
     async def get_revoked_seat_by_container(
         self,
         container: SeatContainer,
@@ -358,10 +411,11 @@ def get_eager_options(self) -> Options:
                 joinedload(Subscription.customer),
             ),
             joinedload(CustomerSeat.order).options(
-                joinedload(Order.product),
+                joinedload(Order.product).joinedload(Product.organization),
                 joinedload(Order.customer).joinedload(Customer.organization),
             ),
             joinedload(CustomerSeat.customer),
+            joinedload(CustomerSeat.member),
         )
 
     def get_eager_options_with_prices(self) -> Options:

server/polar/customer_seat/schemas.py

@@ -95,7 +95,20 @@ class CustomerSeat(TimestampedSchema):
         None, description="The order ID (for one-time purchase seats)"
     )
     status: SeatStatus = Field(..., description="Status of the seat")
-    customer_id: UUID | None = Field(None, description="The assigned customer ID")
+    customer_id: UUID | None = Field(
+        None,
+        description=(
+            "The customer ID. When member_model_enabled is true, this is the billing "
+            "customer (purchaser). When false, this is the seat member customer."
+        ),
+    )
+    member_id: UUID | None = Field(
+        None, description="The member ID of the seat occupant"
+    )
+    email: str | None = Field(
+        None,
+        description="Email of the seat member (set when member_model_enabled is true)",
+    )
     customer_email: str | None = Field(None, description="The assigned customer email")
     invitation_token_expires_at: datetime | None = Field(
         None, description="When the invitation token expires"
@@ -110,20 +123,30 @@ class CustomerSeat(TimestampedSchema):
     @classmethod
     def extract_customer_email(cls, data: Any) -> Any:
         if isinstance(data, dict):
-            # For dict data
-            if "customer" in data and data["customer"]:
+            # For dict data - priority: email > member.email > customer.email
+            if "email" in data and data["email"]:
+                data["customer_email"] = data["email"]
+            elif "member" in data and data["member"]:
+                data["customer_email"] = data.get("member", {}).get("email")
+            elif "customer" in data and data["customer"]:
                 data["customer_email"] = data.get("customer", {}).get("email")
             return data
         elif hasattr(data, "__dict__"):
-            # For SQLAlchemy models - check if customer is loaded
-            state = inspect(data)
-            if "customer" not in state.unloaded:
-                # Customer is loaded, we can extract the email
-                # But we need to let Pydantic handle the model conversion
-                # We'll just add the customer_email field if customer is available
-                if hasattr(data, "customer") and data.customer:
-                    # Add customer_email as a temporary attribute
-                    object.__setattr__(data, "customer_email", data.customer.email)
+            # For SQLAlchemy models - check if email is set on the seat first
+            # Priority: seat.email > seat.member.email > seat.customer.email
+            if hasattr(data, "email") and data.email:
+                object.__setattr__(data, "customer_email", data.email)
+            else:
+                state = inspect(data)
+                # Try member first
+                if "member" not in state.unloaded:
+                    if hasattr(data, "member") and data.member:
+                        object.__setattr__(data, "customer_email", data.member.email)
+                        return data
+                # Fall back to customer
+                if "customer" not in state.unloaded:
+                    if hasattr(data, "customer") and data.customer:
+                        object.__setattr__(data, "customer_email", data.customer.email)
         return data