fix(medusa): Add free shipping functionality (#241)

integration-tests/api/__tests__/store/cart.js

@@ -14,6 +14,19 @@ describe("/store/carts", () => {
   let medusaProcess;
   let dbConnection;
 
+  const doAfterEach = async (manager) => {
+    await manager.query(`DELETE FROM "discount"`);
+    await manager.query(`DELETE FROM "discount_rule"`);
+    await manager.query(`DELETE FROM "shipping_method"`);
+    await manager.query(`DELETE FROM "shipping_option"`);
+    await manager.query(`DELETE FROM "cart"`);
+    await manager.query(`DELETE FROM "customer"`);
+    await manager.query(
+      `UPDATE "country" SET region_id=NULL WHERE iso_2 = 'us'`
+    );
+    await manager.query(`DELETE FROM "region"`);
+  };
+
   beforeAll(async () => {
     const cwd = path.resolve(path.join(__dirname, "..", ".."));
     dbConnection = await initDb({ cwd });
@@ -43,13 +56,7 @@ describe("/store/carts", () => {
 
     afterEach(async () => {
       const manager = dbConnection.manager;
-      await manager.query(`DELETE FROM "cart"`);
-      await manager.query(`DELETE FROM "discount"`);
-      await manager.query(`DELETE FROM "discount_rule"`);
-      await manager.query(
-        `UPDATE "country" SET region_id=NULL WHERE iso_2 = 'us'`
-      );
-      await manager.query(`DELETE FROM "region"`);
+      await doAfterEach(manager);
     });
 
     it("creates a cart", async () => {
@@ -108,14 +115,7 @@ describe("/store/carts", () => {
 
     afterEach(async () => {
       const manager = dbConnection.manager;
-      await manager.query(`DELETE FROM "cart"`);
-      await manager.query(`DELETE FROM "discount"`);
-      await manager.query(`DELETE FROM "discount_rule"`);
-      await manager.query(`DELETE FROM "customer"`);
-      await manager.query(
-        `UPDATE "country" SET region_id=NULL WHERE iso_2 = 'us'`
-      );
-      await manager.query(`DELETE FROM "region"`);
+      await doAfterEach(manager);
     });
 
     it("fails on apply discount if limit has been reached", async () => {
@@ -142,6 +142,73 @@ describe("/store/carts", () => {
 
       expect(response.status).toEqual(200);
     });
+
+    it("adds free shipping to cart then removes it again", async () => {
+      const api = useApi();
+
+      let cart = await api.post(
+        "/store/carts/test-cart",
+        {
+          discounts: [{ code: "FREE_SHIPPING" }, { code: "CREATED" }],
+        },
+        { withCredentials: true }
+      );
+
+      expect(cart.data.cart.shipping_total).toBe(0);
+      expect(cart.status).toEqual(200);
+
+      cart = await api.post(
+        "/store/carts/test-cart",
+        {
+          discounts: [{ code: "CREATED" }],
+        },
+        { withCredentials: true }
+      );
+
+      expect(cart.data.cart.shipping_total).toBe(1000);
+      expect(cart.status).toEqual(200);
+    });
+  });
+
+  describe("DELETE /store/carts/:id/discounts/:code", () => {
+    beforeEach(async () => {
+      try {
+        await cartSeeder(dbConnection);
+        await dbConnection.manager.query(
+          `INSERT INTO "cart_discounts" (cart_id, discount_id) VALUES ('test-cart', 'free-shipping')`
+        );
+      } catch (err) {
+        console.log(err);
+        throw err;
+      }
+    });
+
+    afterEach(async () => {
+      const manager = dbConnection.manager;
+      await doAfterEach(manager);
+    });
+
+    it("removes free shipping and updates shipping total", async () => {
+      const api = useApi();
+
+      const cartWithFreeShipping = await api.post(
+        "/store/carts/test-cart",
+        {
+          discounts: [{ code: "FREE_SHIPPING" }],
+        },
+        { withCredentials: true }
+      );
+
+      expect(cartWithFreeShipping.data.cart.shipping_total).toBe(0);
+      expect(cartWithFreeShipping.status).toEqual(200);
+
+      const response = await api.delete(
+        "/store/carts/test-cart/discounts/FREE_SHIPPING"
+      );
+
+      expect(response.data.cart.shipping_total).toBe(1000);
+      expect(response.status).toEqual(200);
+    });
   });
 
   describe("get-cart with session customer", () => {
@@ -156,14 +223,7 @@ describe("/store/carts", () => {
 
     afterEach(async () => {
       const manager = dbConnection.manager;
-      await manager.query(`DELETE FROM "cart"`);
-      await manager.query(`DELETE FROM "discount"`);
-      await manager.query(`DELETE FROM "discount_rule"`);
-      await manager.query(`DELETE FROM "customer"`);
-      await manager.query(
-        `UPDATE "country" SET region_id=NULL WHERE iso_2 = 'us'`
-      );
-      await manager.query(`DELETE FROM "region"`);
+      await doAfterEach(manager);
     });
 
     it("updates empty cart.customer_id on cart retrieval", async () => {

integration-tests/api/helpers/cart-seeder.js

@@ -4,11 +4,18 @@ const {
   Cart,
   DiscountRule,
   Discount,
+  ShippingProfile,
+  ShippingOption,
+  ShippingMethod,
 } = require("@medusajs/medusa");
 
 module.exports = async (connection, data = {}) => {
   const manager = connection.manager;
 
+  const defaultProfile = await manager.findOne(ShippingProfile, {
+    type: "default",
+  });
+
   const r = manager.create(Region, {
     id: "test-region",
     name: "Test Region",
@@ -16,24 +23,26 @@ module.exports = async (connection, data = {}) => {
     tax_rate: 0,
   });
 
-  await manager.insert(DiscountRule, {
-    id: "test-discount-rule",
-    description: "Dynamic rule",
-    type: "percentage",
-    value: 10,
+  const freeRule = manager.create(DiscountRule, {
+    id: "free-shipping-rule",
+    description: "Free shipping rule",
+    type: "free_shipping",
+    value: 100,
     allocation: "total",
   });
 
-  await manager.insert(Discount, {
-    id: "test-discount",
-    code: "DYNAMIC",
-    rule_id: "test-discount-rule",
-    is_dynamic: true,
-    usage_count: 0,
-    usage_limit: 1,
+  const freeDisc = manager.create(Discount, {
+    id: "free-shipping",
+    code: "FREE_SHIPPING",
+    is_dynamic: false,
     is_disabled: false,
   });
 
+  freeDisc.regions = [r];
+  freeDisc.rule = freeRule;
+
+  await manager.save(freeDisc);
+
   const d = await manager.create(Discount, {
     id: "test-discount",
     code: "CREATED",
@@ -73,6 +82,17 @@ module.exports = async (connection, data = {}) => {
     email: "some-customer@email.com",
   });
 
+  await manager.insert(ShippingOption, {
+    id: "test-option",
+    name: "test-option",
+    provider_id: "test-ful",
+    region_id: "test-region",
+    profile_id: defaultProfile.id,
+    price_type: "flat_rate",
+    amount: 1000,
+    data: {},
+  });
+
   const cart = manager.create(Cart, {
     id: "test-cart",
     customer_id: "some-customer",
@@ -88,4 +108,12 @@ module.exports = async (connection, data = {}) => {
   });
 
   await manager.save(cart);
+
+  await manager.insert(ShippingMethod, {
+    id: "test-method",
+    shipping_option_id: "test-option",
+    cart_id: "test-cart",
+    price: 1000,
+    data: {},
+  });
 };

packages/medusa/src/api/routes/store/carts/__tests__/update-cart.js

@@ -65,7 +65,7 @@ describe("POST /store/carts/:id", () => {
       expect(CartServiceMock.retrieve).toHaveBeenCalledWith(
         IdMap.getId("emptyCart"),
         {
-          relations: ["payment_sessions"],
+          relations: ["payment_sessions", "shipping_methods"],
         }
       )
       expect(CartServiceMock.retrieve).toHaveBeenCalledWith(

packages/medusa/src/api/routes/store/carts/update-cart.js

@@ -104,7 +104,7 @@ export default async (req, res) => {
 
     // If the cart has payment sessions update these
     const updated = await cartService.retrieve(id, {
-      relations: ["payment_sessions"],
+      relations: ["payment_sessions", "shipping_methods"],
     })
 
     if (updated.payment_sessions?.length && !value.region_id) {

packages/medusa/src/services/__tests__/cart.js

@@ -1281,6 +1281,7 @@ describe("CartService", () => {
             profile_id: IdMap.getId(m.profile),
           },
         })),
+        discounts: [],
       }
     }
 

packages/medusa/src/services/cart.js

@@ -1,7 +1,6 @@
 import _ from "lodash"
 import { Validator, MedusaError } from "medusa-core-utils"
 import { BaseService } from "medusa-interfaces"
-import { defaultFields, defaultRelations } from "../api/routes/store/carts"
 
 /**
  * Provides layer to manipulate carts.
@@ -574,6 +573,49 @@ class CartService extends BaseService {
     })
   }
 
+  /**
+   * Ensures shipping total on cart is correct in regards to a potential free
+   * shipping discount
+   * If a free shipping is present, we set shipping methods price to 0
+   * if a free shipping was present, we set shipping methods to original amount
+   * @param {Cart} cart - the the cart to adjust free shipping for
+   * @param {boolean} shouldAdd - flag to indicate, if we should add or remove
+   */
+  async adjustFreeShipping_(cart, shouldAdd) {
+    if (cart.shipping_methods?.length) {
+      // if any free shipping discounts, we ensure to update shipping method amount
+      if (shouldAdd) {
+        await Promise.all(
+          cart.shipping_methods.map(async sm => {
+            const smRepo = this.manager_.getCustomRepository(
+              this.shippingMethodRepository_
+            )
+
+            const method = await smRepo.findOne({ where: { id: sm.id } })
+
+            if (method) {
+              method.price = 0
+              await smRepo.save(method)
+            }
+          })
+        )
+      } else {
+        await Promise.all(
+          cart.shipping_methods.map(async sm => {
+            const smRepo = this.manager_.getCustomRepository(
+              this.shippingMethodRepository_
+            )
+
+            // if free shipping discount is removed, we adjust the shipping
+            // back to its original amount
+            sm.price = sm.shipping_option.amount
+            await smRepo.save(sm)
+          })
+        )
+      }
+    }
+  }
+
   async update(cartId, update) {
     return this.atomicPhase_(async manager => {
       const cartRepo = manager.getCustomRepository(this.cartRepository_)
@@ -627,10 +669,29 @@ class CartService extends BaseService {
       }
 
       if ("discounts" in update) {
+        const previousDiscounts = cart.discounts
         cart.discounts = []
+
         for (const { code } of update.discounts) {
           await this.applyDiscount_(cart, code)
         }
+
+        const hasFreeShipping = cart.discounts.some(
+          ({ rule }) => rule.type === "free_shipping"
+        )
+
+        // if we previously had a free shipping discount and then removed it,
+        // we need to update shipping methods to original price
+        if (
+          previousDiscounts.some(({ rule }) => rule.type === "free_shipping") &&
+          !hasFreeShipping
+        ) {
+          await this.adjustFreeShipping_(cart, false)
+        }
+
+        if (hasFreeShipping) {
+          await this.adjustFreeShipping_(cart, true)
+        }
       }
 
       if ("gift_cards" in update) {
@@ -890,8 +951,13 @@ class CartService extends BaseService {
   async removeDiscount(cartId, discountCode) {
     return this.atomicPhase_(async manager => {
       const cart = await this.retrieve(cartId, {
-        relations: ["discounts", "payment_sessions"],
+        relations: ["discounts", "payment_sessions", "shipping_methods"],
       })
+
+      if (cart.discounts.some(({ rule }) => rule.type === "free_shipping")) {
+        await this.adjustFreeShipping_(cart, false)
+      }
+
       cart.discounts = cart.discounts.filter(d => d.code !== discountCode)
 
       const cartRepo = manager.getCustomRepository(this.cartRepository_)
@@ -1232,6 +1298,7 @@ class CartService extends BaseService {
         select: ["subtotal"],
         relations: [
           "shipping_methods",
+          "discounts",
           "shipping_methods.shipping_option",
           "items",
           "items.variant",
@@ -1267,7 +1334,15 @@ class CartService extends BaseService {
         })
       }
 
-      const result = await this.retrieve(cartId)
+      const result = await this.retrieve(cartId, {
+        relations: ["discounts", "shipping_methods"],
+      })
+
+      // if cart has freeshipping, adjust price
+      if (result.discounts.some(({ rule }) => rule.type === "free_shipping")) {
+        await this.adjustFreeShipping_(result, true)
+      }
+
       await this.eventBus_
         .withTransaction(manager)
         .emit(CartService.Events.UPDATED, result)

packages/medusa/src/services/swap.js

@@ -400,8 +400,13 @@ class SwapService extends BaseService {
 
       const order = swap.order
 
+      // filter out free shipping discounts
+      const discounts =
+        order?.discounts?.filter(({ rule }) => rule.type !== "free_shipping") ||
+        undefined
+
       const cart = await this.cartService_.withTransaction(manager).create({
-        discounts: order.discounts,
+        discounts,
         email: order.email,
         billing_address_id: order.billing_address_id,
         shipping_address_id: order.shipping_address_id,