fix(core-flows): handle cacluated shipping options on draft orders gracefully (#13353)

* fix(core-flows): handle calculated shipping options on draft orders gracefully

* fix: throw medusa error

.changeset/hot-impalas-retire.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/core-flows": patch
+---
+
+fix(core-flows): handle cacluated shipping options on draft orders gracefully

packages/core/core-flows/src/draft-order/workflows/add-draft-order-shipping-methods.ts

@@ -1,16 +1,25 @@
 import {
   ChangeActionType,
+  isDefined,
+  MedusaError,
   OrderChangeStatus,
   PromotionActions,
+  ShippingOptionPriceType,
 } from "@medusajs/framework/utils"
 import {
+  createStep,
   createWorkflow,
   transform,
   when,
   WorkflowData,
   WorkflowResponse,
 } from "@medusajs/framework/workflows-sdk"
-import { BigNumberInput, OrderChangeDTO, OrderDTO } from "@medusajs/types"
+import {
+  BigNumberInput,
+  OrderChangeDTO,
+  OrderDTO,
+  ShippingOptionDTO,
+} from "@medusajs/types"
 import { useRemoteQueryStep } from "../../common"
 import {
   createOrderChangeActionsWorkflow,
@@ -23,6 +32,27 @@ import { validateDraftOrderChangeStep } from "../steps/validate-draft-order-chan
 import { draftOrderFieldsForRefreshSteps } from "../utils/fields"
 import { refreshDraftOrderAdjustmentsWorkflow } from "./refresh-draft-order-adjustments"
 
+const validateShippingOptionStep = createStep(
+  "validate-shipping-option",
+  async (data: {
+    shippingOptions: ShippingOptionDTO[]
+    input: AddDraftOrderShippingMethodsWorkflowInput
+  }) => {
+    const shippingOption = data.shippingOptions[0]
+    const customAmount = data.input.custom_amount
+
+    if (
+      shippingOption.price_type === ShippingOptionPriceType.CALCULATED &&
+      !isDefined(customAmount)
+    ) {
+      throw new MedusaError(
+        MedusaError.Types.INVALID_DATA,
+        "Calculated shipping options are not currently supported on draft orders without a custom amount."
+      )
+    }
+  }
+)
+
 export const addDraftOrderShippingMethodsWorkflowId =
   "add-draft-order-shipping-methods"
 
@@ -100,6 +130,7 @@ export const addDraftOrderShippingMethodsWorkflow = createWorkflow(
       fields: [
         "id",
         "name",
+        "price_type",
         "calculated_price.calculated_amount",
         "calculated_price.is_calculated_price_tax_inclusive",
       ],
@@ -111,6 +142,8 @@ export const addDraftOrderShippingMethodsWorkflow = createWorkflow(
       },
     }).config({ name: "fetch-shipping-option" })
 
+    validateShippingOptionStep({ shippingOptions, input })
+
     const shippingMethodInput = transform(
       {
         relatedEntity: { order_id: order.id },

packages/core/core-flows/src/order/utils/prepare-shipping-method.ts

@@ -14,7 +14,7 @@ export function prepareShippingMethod(relatedEntityField?: string) {
         : option.calculated_price.calculated_amount,
       is_custom_amount: isCustomPrice,
       is_tax_inclusive:
-        !!option.calculated_price.is_calculated_price_tax_inclusive,
+        !!option.calculated_price?.is_calculated_price_tax_inclusive,
       data: option.data ?? {},
       name: option.name,
       version: orderChange.version,