feat(cart): Line item adjustments (#6112)

.changeset/sour-geckos-wash.md

@@ -0,0 +1,6 @@
+---
+"@medusajs/types": patch
+"@medusajs/utils": patch
+---
+
+feat(cart): Line item adjustments

packages/cart/integration-tests/__tests__/services/cart-module/index.spec.ts

@@ -799,4 +799,515 @@ describe("Cart Module Service", () => {
       expect(cart.shipping_methods?.length).toBe(0)
     })
   })
+
+  describe("setLineItemAdjustments", () => {
+    it("should set line item adjustments for a cart", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const [itemTwo] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 2,
+          unit_price: 200,
+          title: "test-2",
+        },
+      ])
+
+      const adjustments = await service.setLineItemAdjustments(createdCart.id, [
+        {
+          item_id: itemOne.id,
+          amount: 100,
+          code: "FREE",
+        },
+        {
+          item_id: itemTwo.id,
+          amount: 200,
+          code: "FREE-2",
+        },
+      ])
+
+      expect(adjustments).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            item_id: itemOne.id,
+            amount: 100,
+            code: "FREE",
+          }),
+          expect.objectContaining({
+            item_id: itemTwo.id,
+            amount: 200,
+            code: "FREE-2",
+          }),
+        ])
+      )
+    })
+
+    it("should replace line item adjustments for a cart", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const adjustments = await service.setLineItemAdjustments(createdCart.id, [
+        {
+          item_id: itemOne.id,
+          amount: 100,
+          code: "FREE",
+        },
+      ])
+
+      expect(adjustments).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            item_id: itemOne.id,
+            amount: 100,
+            code: "FREE",
+          }),
+        ])
+      )
+
+      await service.setLineItemAdjustments(createdCart.id, [
+        {
+          item_id: itemOne.id,
+          amount: 50,
+          code: "50%",
+        },
+      ])
+
+      const cart = await service.retrieve(createdCart.id, {
+        relations: ["items.adjustments"],
+      })
+
+      expect(cart.items).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            id: itemOne.id,
+            adjustments: expect.arrayContaining([
+              expect.objectContaining({
+                item_id: itemOne.id,
+                amount: 50,
+                code: "50%",
+              }),
+            ]),
+          }),
+        ])
+      )
+
+      expect(cart.items?.length).toBe(1)
+      expect(cart.items?.[0].adjustments?.length).toBe(1)
+    })
+
+    it("should remove all line item adjustments for a cart", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const adjustments = await service.setLineItemAdjustments(createdCart.id, [
+        {
+          item_id: itemOne.id,
+          amount: 100,
+          code: "FREE",
+        },
+      ])
+
+      expect(adjustments).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            item_id: itemOne.id,
+            amount: 100,
+            code: "FREE",
+          }),
+        ])
+      )
+
+      await service.setLineItemAdjustments(createdCart.id, [])
+
+      const cart = await service.retrieve(createdCart.id, {
+        relations: ["items.adjustments"],
+      })
+
+      expect(cart.items).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            id: itemOne.id,
+            adjustments: [],
+          }),
+        ])
+      )
+
+      expect(cart.items?.length).toBe(1)
+      expect(cart.items?.[0].adjustments?.length).toBe(0)
+    })
+
+    it("should update line item adjustments for a cart", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const adjustments = await service.setLineItemAdjustments(createdCart.id, [
+        {
+          item_id: itemOne.id,
+          amount: 100,
+          code: "FREE",
+        },
+      ])
+
+      expect(adjustments).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            item_id: itemOne.id,
+            amount: 100,
+            code: "FREE",
+          }),
+        ])
+      )
+
+      await service.setLineItemAdjustments(createdCart.id, [
+        {
+          id: adjustments[0].id,
+          amount: 50,
+          code: "50%",
+        },
+      ])
+
+      const cart = await service.retrieve(createdCart.id, {
+        relations: ["items.adjustments"],
+      })
+
+      expect(cart.items).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            id: itemOne.id,
+            adjustments: [
+              expect.objectContaining({
+                id: adjustments[0].id,
+                item_id: itemOne.id,
+                amount: 50,
+                code: "50%",
+              }),
+            ],
+          }),
+        ])
+      )
+
+      expect(cart.items?.length).toBe(1)
+      expect(cart.items?.[0].adjustments?.length).toBe(1)
+    })
+  })
+
+  describe("addLineItemAdjustments", () => {
+    it("should add line item adjustments for items in a cart", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const adjustments = await service.addLineItemAdjustments(createdCart.id, [
+        {
+          item_id: itemOne.id,
+          amount: 100,
+          code: "FREE",
+        },
+      ])
+
+      expect(adjustments).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            item_id: itemOne.id,
+            amount: 100,
+            code: "FREE",
+          }),
+        ])
+      )
+    })
+
+    it("should add multiple line item adjustments for multiple line items", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+      const [itemTwo] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 2,
+          unit_price: 200,
+          title: "test-2",
+        },
+      ])
+
+      const adjustments = await service.addLineItemAdjustments(createdCart.id, [
+        {
+          item_id: itemOne.id,
+          amount: 100,
+          code: "FREE",
+        },
+        {
+          item_id: itemTwo.id,
+          amount: 150,
+          code: "CODE-2",
+        },
+      ])
+
+      expect(adjustments).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            item_id: itemOne.id,
+            amount: 100,
+            code: "FREE",
+          }),
+          expect.objectContaining({
+            item_id: itemTwo.id,
+            amount: 150,
+            code: "CODE-2",
+          }),
+        ])
+      )
+    })
+
+    it("should add line item adjustments for line items on multiple carts", async () => {
+      const [cartOne] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+      const [cartTwo] = await service.create([
+        {
+          currency_code: "usd",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(cartOne.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+      const [itemTwo] = await service.addLineItems(cartTwo.id, [
+        {
+          quantity: 2,
+          unit_price: 200,
+          title: "test-2",
+        },
+      ])
+
+      await service.addLineItemAdjustments([
+        // item from cart one
+        {
+          item_id: itemOne.id,
+          amount: 100,
+          code: "FREE",
+        },
+        // item from cart two
+        {
+          item_id: itemTwo.id,
+          amount: 150,
+          code: "CODE-2",
+        },
+      ])
+
+      const cartOneItems = await service.listLineItems(
+        { cart_id: cartOne.id },
+        { relations: ["adjustments"] }
+      )
+      const cartTwoItems = await service.listLineItems(
+        { cart_id: cartTwo.id },
+        { relations: ["adjustments"] }
+      )
+
+      expect(cartOneItems).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            adjustments: expect.arrayContaining([
+              expect.objectContaining({
+                item_id: itemOne.id,
+                amount: 100,
+                code: "FREE",
+              }),
+            ]),
+          }),
+        ])
+      )
+      expect(cartTwoItems).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            adjustments: expect.arrayContaining([
+              expect.objectContaining({
+                item_id: itemTwo.id,
+                amount: 150,
+                code: "CODE-2",
+              }),
+            ]),
+          }),
+        ])
+      )
+    })
+
+    it("should throw if line item is not associated with cart", async () => {
+      const [cartOne] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [cartTwo] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [itemOne] = await service.addLineItems(cartOne.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const error = await service
+        .addLineItemAdjustments(cartTwo.id, [
+          {
+            item_id: itemOne.id,
+            amount: 100,
+            code: "FREE",
+          },
+        ])
+        .catch((e) => e)
+
+      expect(error.message).toBe(
+        `Line item with id ${itemOne.id} does not exist on cart with id ${cartTwo.id}`
+      )
+    })
+  })
+
+  describe("removeLineItemAdjustments", () => {
+    it("should remove a line item succesfully", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [item] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const [adjustment] = await service.addLineItemAdjustments(
+        createdCart.id,
+        [
+          {
+            item_id: item.id,
+            amount: 50,
+          },
+        ]
+      )
+
+      expect(adjustment.item_id).toBe(item.id)
+
+      await service.removeLineItemAdjustments(adjustment.id)
+
+      const adjustments = await service.listLineItemAdjustments({
+        item_id: item.id,
+      })
+
+      expect(adjustments?.length).toBe(0)
+    })
+
+    it("should remove a line item succesfully with selector", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [item] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const [adjustment] = await service.addLineItemAdjustments(
+        createdCart.id,
+        [
+          {
+            item_id: item.id,
+            amount: 50,
+          },
+        ]
+      )
+
+      expect(adjustment.item_id).toBe(item.id)
+
+      await service.removeLineItemAdjustments({ item_id: item.id })
+
+      const adjustments = await service.listLineItemAdjustments({
+        item_id: item.id,
+      })
+
+      expect(adjustments?.length).toBe(0)
+    })
+  })
 })

packages/cart/jest.config.js

@@ -3,6 +3,8 @@ module.exports = {
     "^@models": "<rootDir>/src/models",
     "^@services": "<rootDir>/src/services",
     "^@repositories": "<rootDir>/src/repositories",
+    "^@types": "<rootDir>/src/types",
+    "^@utils": "<rootDir>/src/utils",
   },
   transform: {
     "^.+\\.[jt]s?$": [

packages/cart/src/index.ts

@@ -1,7 +1,7 @@
-import { moduleDefinition } from "./module-definition"
 import { Modules } from "@medusajs/modules-sdk"
-import * as Models from "@models"
 import { ModulesSdkUtils } from "@medusajs/utils"
+import * as Models from "@models"
+import { moduleDefinition } from "./module-definition"
 
 export default moduleDefinition
 
@@ -20,3 +20,4 @@ export const revertMigration = ModulesSdkUtils.buildRevertMigrationScript(
 
 export * from "./initialize"
 export * from "./loaders"
+

packages/cart/src/models/adjustment-line.ts

@@ -14,19 +14,19 @@ export default abstract class AdjustmentLine {
   id: string
 
   @Property({ columnType: "text", nullable: true })
-  description?: string | null
+  description: string | null = null
 
   @Property({ columnType: "text", nullable: true })
-  promotion_id?: string | null
+  promotion_id: string | null = null
 
-  @Property({ columnType: "text" })
-  code: string
+  @Property({ columnType: "text", nullable: true })
+  code: string | null = null
 
-  @Property({ columnType: "numeric" })
+  @Property({ columnType: "numeric", serializer: Number })
   amount: number
 
   @Property({ columnType: "text", nullable: true })
-  provider_id?: string | null
+  provider_id: string | null = null
 
   @Property({
     onCreate: () => new Date(),

packages/cart/src/models/index.ts

@@ -1,7 +1,7 @@
 export { default as Address } from "./address"
 export { default as Cart } from "./cart"
 export { default as LineItem } from "./line-item"
-export { default as LineItemAdjustmentLine } from "./line-item-adjustment-line"
+export { default as LineItemAdjustment } from "./line-item-adjustment"
 export { default as LineItemTaxLine } from "./line-item-tax-line"
 export { default as ShippingMethod } from "./shipping-method"
 export { default as ShippingMethodAdjustmentLine } from "./shipping-method-adjustment-line"

packages/cart/src/models/line-item-adjustment.ts

@@ -1,20 +1,29 @@
 import { generateEntityId } from "@medusajs/utils"
 import {
   BeforeCreate,
+  Check,
   Entity,
   ManyToOne,
-  OnInit
+  OnInit,
+  Property,
 } from "@mikro-orm/core"
 import AdjustmentLine from "./adjustment-line"
 import LineItem from "./line-item"
 
 @Entity({ tableName: "cart_line_item_adjustment_line" })
-export default class LineItemAdjustmentLine extends AdjustmentLine {
+@Check<LineItemAdjustment>({
+  expression: (columns) => `${columns.amount} >= 0`,
+})
+export default class LineItemAdjustment extends AdjustmentLine {
   @ManyToOne(() => LineItem, {
-    joinColumn: "line_item",
-    fieldName: "line_item_id",
+    onDelete: "cascade",
+    nullable: true,
+    index: "IDX_adjustment_line_item_id",
   })
-  line_item: LineItem
+  item?: LineItem | null
+
+  @Property({ columnType: "text" })
+  item_id: string
 
   @BeforeCreate()
   onCreate() {

packages/cart/src/models/line-item.ts

@@ -14,7 +14,7 @@ import {
   Property,
 } from "@mikro-orm/core"
 import Cart from "./cart"
-import LineItemAdjustmentLine from "./line-item-adjustment-line"
+import LineItemAdjustment from "./line-item-adjustment"
 import LineItemTaxLine from "./line-item-tax-line"
 
 type OptionalLineItemProps =
@@ -116,13 +116,13 @@ export default class LineItem {
   tax_lines = new Collection<LineItemTaxLine>(this)
 
   @OneToMany(
-    () => LineItemAdjustmentLine,
-    (adjustment) => adjustment.line_item,
+    () => LineItemAdjustment,
+    (adjustment) => adjustment.item,
     {
       cascade: [Cascade.REMOVE],
     }
   )
-  adjustments = new Collection<LineItemAdjustmentLine>(this)
+  adjustments = new Collection<LineItemAdjustment>(this)
 
   /** COMPUTED PROPERTIES - START */
 

packages/cart/src/module-definition.ts

@@ -1,7 +1,7 @@
 import { ModuleExports } from "@medusajs/types"
-import { CartModuleService } from "@services"
 import loadConnection from "./loaders/connection"
 import loadContainer from "./loaders/container"
+import { CartModuleService } from "./services"
 
 const service = CartModuleService
 const loaders = [loadContainer, loadConnection] as any

packages/cart/src/repositories/index.ts

@@ -1 +1,2 @@
-export { MikroOrmBaseRepository as BaseRepository } from "@medusajs/utils"
+export { MikroOrmBaseRepository as BaseRepository } from "@medusajs/utils";
+

packages/cart/src/services/cart-module.ts

@@ -1,23 +1,21 @@
 import {
+  CartTypes,
   Context,
   DAL,
-  FilterableCartProps,
   FindConfig,
   ICartModuleService,
   InternalModuleDeclaration,
   ModuleJoinerConfig,
 } from "@medusajs/types"
-
-import { CartTypes } from "@medusajs/types"
-
 import {
   InjectManager,
   InjectTransactionManager,
   MedusaContext,
+  MedusaError,
   isObject,
   isString,
 } from "@medusajs/utils"
-import { Cart, LineItem, ShippingMethod } from "@models"
+import { Cart, LineItem, LineItemAdjustment, ShippingMethod } from "@models"
 import { CreateLineItemDTO, UpdateLineItemDTO } from "@types"
 import { joinerConfig } from "../joiner-config"
 import * as services from "../services"
@@ -28,6 +26,7 @@ type InjectedDependencies = {
   addressService: services.AddressService
   lineItemService: services.LineItemService
   shippingMethodService: services.ShippingMethodService
+  lineItemAdjustmentService: services.LineItemAdjustmentService
 }
 
 export default class CartModuleService implements ICartModuleService {
@@ -36,6 +35,7 @@ export default class CartModuleService implements ICartModuleService {
   protected addressService_: services.AddressService
   protected lineItemService_: services.LineItemService
   protected shippingMethodService_: services.ShippingMethodService
+  protected lineItemAdjustmentService_: services.LineItemAdjustmentService
 
   constructor(
     {
@@ -44,6 +44,7 @@ export default class CartModuleService implements ICartModuleService {
       addressService,
       lineItemService,
       shippingMethodService,
+      lineItemAdjustmentService,
     }: InjectedDependencies,
     protected readonly moduleDeclaration: InternalModuleDeclaration
   ) {
@@ -52,6 +53,7 @@ export default class CartModuleService implements ICartModuleService {
     this.addressService_ = addressService
     this.lineItemService_ = lineItemService
     this.shippingMethodService_ = shippingMethodService
+    this.lineItemAdjustmentService_ = lineItemAdjustmentService
   }
 
   __joinerConfig(): ModuleJoinerConfig {
@@ -86,7 +88,7 @@ export default class CartModuleService implements ICartModuleService {
 
   @InjectManager("baseRepository_")
   async listAndCount(
-    filters: FilterableCartProps = {},
+    filters: CartTypes.FilterableCartProps = {},
     config: FindConfig<CartTypes.CartDTO> = {},
     @MedusaContext() sharedContext: Context = {}
   ): Promise<[CartTypes.CartDTO[], number]> {
@@ -244,14 +246,14 @@ export default class CartModuleService implements ICartModuleService {
     itemId: string,
     config: FindConfig<CartTypes.CartLineItemDTO> = {},
     @MedusaContext() sharedContext: Context = {}
-  ) {
+  ): Promise<CartTypes.CartLineItemDTO> {
     const item = await this.lineItemService_.retrieve(
       itemId,
       config,
       sharedContext
     )
 
-    return await this.baseRepository_.serialize<CartTypes.CartLineItemDTO[]>(
+    return await this.baseRepository_.serialize<CartTypes.CartLineItemDTO>(
       item,
       {
         populate: true,
@@ -300,7 +302,7 @@ export default class CartModuleService implements ICartModuleService {
 
   addLineItems(
     data: CartTypes.CreateLineItemForCartDTO
-  ): Promise<CartTypes.CartLineItemDTO>
+  ): Promise<CartTypes.CartLineItemDTO[]>
   addLineItems(
     data: CartTypes.CreateLineItemForCartDTO[]
   ): Promise<CartTypes.CartLineItemDTO[]>
@@ -318,7 +320,7 @@ export default class CartModuleService implements ICartModuleService {
       | CartTypes.CreateLineItemForCartDTO,
     data?: CartTypes.CreateLineItemDTO[] | CartTypes.CreateLineItemDTO,
     @MedusaContext() sharedContext: Context = {}
-  ): Promise<CartTypes.CartLineItemDTO[] | CartTypes.CartLineItemDTO> {
+  ): Promise<CartTypes.CartLineItemDTO[]> {
     let items: LineItem[] = []
     if (isString(cartIdOrData)) {
       items = await this.addLineItems_(
@@ -592,7 +594,9 @@ export default class CartModuleService implements ICartModuleService {
       | string
       | CartTypes.CreateShippingMethodDTO[]
       | CartTypes.CreateShippingMethodDTO,
-    data?: CartTypes.CreateShippingMethodDTO[],
+    data?:
+      | CartTypes.CreateShippingMethodDTO[]
+      | CartTypes.CreateShippingMethodForSingleCartDTO[],
     @MedusaContext() sharedContext: Context = {}
   ): Promise<
     CartTypes.CartShippingMethodDTO[] | CartTypes.CartShippingMethodDTO
@@ -601,12 +605,15 @@ export default class CartModuleService implements ICartModuleService {
     if (isString(cartIdOrData)) {
       methods = await this.addShippingMethods_(
         cartIdOrData,
-        data as CartTypes.CreateShippingMethodDTO[],
+        data as CartTypes.CreateShippingMethodForSingleCartDTO[],
         sharedContext
       )
     } else {
       const data = Array.isArray(cartIdOrData) ? cartIdOrData : [cartIdOrData]
-      methods = await this.addShippingMethodsBulk_(data, sharedContext)
+      methods = await this.addShippingMethodsBulk_(
+        data as CartTypes.CreateShippingMethodDTO[],
+        sharedContext
+      )
     }
 
     return await this.baseRepository_.serialize<
@@ -619,7 +626,7 @@ export default class CartModuleService implements ICartModuleService {
   @InjectTransactionManager("baseRepository_")
   protected async addShippingMethods_(
     cartId: string,
-    data: CartTypes.CreateShippingMethodDTO[],
+    data: CartTypes.CreateShippingMethodForSingleCartDTO[],
     @MedusaContext() sharedContext: Context = {}
   ): Promise<ShippingMethod[]> {
     const cart = await this.retrieve(cartId, { select: ["id"] }, sharedContext)
@@ -681,4 +688,198 @@ export default class CartModuleService implements ICartModuleService {
     }
     await this.shippingMethodService_.delete(toDelete, sharedContext)
   }
+
+  @InjectManager("baseRepository_")
+  async listLineItemAdjustments(
+    filters: CartTypes.FilterableLineItemAdjustmentProps = {},
+    config: FindConfig<CartTypes.LineItemAdjustmentDTO> = {},
+    @MedusaContext() sharedContext: Context = {}
+  ) {
+    const adjustments = await this.lineItemAdjustmentService_.list(
+      filters,
+      config,
+      sharedContext
+    )
+
+    return await this.baseRepository_.serialize<
+      CartTypes.LineItemAdjustmentDTO[]
+    >(adjustments, {
+      populate: true,
+    })
+  }
+
+  async addLineItemAdjustments(
+    adjustments: CartTypes.CreateLineItemAdjustmentDTO[]
+  ): Promise<CartTypes.LineItemAdjustmentDTO[]>
+  async addLineItemAdjustments(
+    adjustment: CartTypes.CreateLineItemAdjustmentDTO
+  ): Promise<CartTypes.LineItemAdjustmentDTO[]>
+  async addLineItemAdjustments(
+    cartId: string,
+    adjustments: CartTypes.CreateLineItemAdjustmentDTO[],
+    sharedContext?: Context
+  ): Promise<CartTypes.LineItemAdjustmentDTO[]>
+
+  @InjectTransactionManager("baseRepository_")
+  async addLineItemAdjustments(
+    cartIdOrData:
+      | string
+      | CartTypes.CreateLineItemAdjustmentDTO[]
+      | CartTypes.CreateLineItemAdjustmentDTO,
+    adjustments?: CartTypes.CreateLineItemAdjustmentDTO[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<CartTypes.LineItemAdjustmentDTO[]> {
+    let addedAdjustments: LineItemAdjustment[] = []
+    if (isString(cartIdOrData)) {
+      const cart = await this.retrieve(
+        cartIdOrData,
+        { select: ["id"], relations: ["items"] },
+        sharedContext
+      )
+
+      const lineIds = cart.items?.map((item) => item.id)
+
+      for (const adj of adjustments || []) {
+        if (!lineIds?.includes(adj.item_id)) {
+          throw new MedusaError(
+            MedusaError.Types.INVALID_DATA,
+            `Line item with id ${adj.item_id} does not exist on cart with id ${cartIdOrData}`
+          )
+        }
+      }
+
+      addedAdjustments = await this.lineItemAdjustmentService_.create(
+        adjustments as CartTypes.CreateLineItemAdjustmentDTO[],
+        sharedContext
+      )
+    } else {
+      const data = Array.isArray(cartIdOrData) ? cartIdOrData : [cartIdOrData]
+
+      addedAdjustments = await this.lineItemAdjustmentService_.create(
+        data as CartTypes.CreateLineItemAdjustmentDTO[],
+        sharedContext
+      )
+    }
+
+    return await this.baseRepository_.serialize<
+      CartTypes.LineItemAdjustmentDTO[]
+    >(addedAdjustments, {
+      populate: true,
+    })
+  }
+
+  @InjectTransactionManager("baseRepository_")
+  async setLineItemAdjustments(
+    cartId: string,
+    adjustments: (
+      | CartTypes.CreateLineItemAdjustmentDTO
+      | CartTypes.UpdateLineItemAdjustmentDTO
+    )[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<CartTypes.LineItemAdjustmentDTO[]> {
+    const cart = await this.retrieve(
+      cartId,
+      { select: ["id"], relations: ["items.adjustments"] },
+      sharedContext
+    )
+
+    const lineIds = cart.items?.map((item) => item.id)
+
+    const existingAdjustments = await this.listLineItemAdjustments(
+      { item_id: lineIds },
+      { select: ["id"] },
+      sharedContext
+    )
+
+    let toUpdate: CartTypes.UpdateLineItemAdjustmentDTO[] = []
+    let toCreate: CartTypes.CreateLineItemAdjustmentDTO[] = []
+    for (const adj of adjustments) {
+      if ("id" in adj) {
+        toUpdate.push(adj as CartTypes.UpdateLineItemAdjustmentDTO)
+      } else {
+        toCreate.push(adj as CartTypes.CreateLineItemAdjustmentDTO)
+      }
+    }
+
+    const adjustmentsSet = new Set(toUpdate.map((a) => a.id))
+
+    const toDelete: CartTypes.LineItemAdjustmentDTO[] = []
+
+    // From the existing adjustments, find the ones that are not passed in adjustments
+    existingAdjustments.forEach((adj: CartTypes.LineItemAdjustmentDTO) => {
+      if (!adjustmentsSet.has(adj.id)) {
+        toDelete.push(adj)
+      }
+    })
+
+    await this.lineItemAdjustmentService_.delete(
+      toDelete.map((adj) => adj!.id),
+      sharedContext
+    )
+
+    let result: LineItemAdjustment[] = []
+
+    // TODO: Replace the following two calls with a single bulk upsert call
+    if (toUpdate?.length) {
+      const updated = await this.lineItemAdjustmentService_.update(
+        toUpdate,
+        sharedContext
+      )
+      result.push(...updated)
+    }
+
+    if (toCreate?.length) {
+      const created = await this.lineItemAdjustmentService_.create(
+        toCreate,
+        sharedContext
+      )
+      result.push(...created)
+    }
+
+    return await this.baseRepository_.serialize<
+      CartTypes.LineItemAdjustmentDTO[]
+    >(result, {
+      populate: true,
+    })
+  }
+
+  async removeLineItemAdjustments(
+    adjustmentIds: string[],
+    sharedContext?: Context
+  ): Promise<void>
+  async removeLineItemAdjustments(
+    adjustmentId: string,
+    sharedContext?: Context
+  ): Promise<void>
+  async removeLineItemAdjustments(
+    selector: Partial<CartTypes.LineItemAdjustmentDTO>,
+    sharedContext?: Context
+  ): Promise<void>
+
+  async removeLineItemAdjustments(
+    adjustmentIdsOrSelector:
+      | string
+      | string[]
+      | Partial<CartTypes.LineItemAdjustmentDTO>,
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<void> {
+    let ids: string[] = []
+    if (isObject(adjustmentIdsOrSelector)) {
+      const adjustments = await this.listLineItemAdjustments(
+        {
+          ...adjustmentIdsOrSelector,
+        } as Partial<CartTypes.LineItemAdjustmentDTO>,
+        { select: ["id"] },
+        sharedContext
+      )
+
+      ids = adjustments.map((adj) => adj.id)
+    } else {
+      ids = Array.isArray(adjustmentIdsOrSelector)
+        ? adjustmentIdsOrSelector
+        : [adjustmentIdsOrSelector]
+    }
+
+    await this.lineItemAdjustmentService_.delete(ids, sharedContext)
+  }
 }

packages/cart/src/services/index.ts

@@ -2,5 +2,6 @@ export { default as AddressService } from "./address"
 export { default as CartService } from "./cart"
 export { default as CartModuleService } from "./cart-module"
 export { default as LineItemService } from "./line-item"
+export { default as LineItemAdjustmentService } from "./line-item-adjustment"
 export { default as ShippingMethodService } from "./shipping-method"
 

packages/cart/src/services/line-item-adjustment.ts

@@ -0,0 +1,26 @@
+import { DAL } from "@medusajs/types"
+import { ModulesSdkUtils } from "@medusajs/utils"
+import { LineItemAdjustment } from "@models"
+import {
+  CreateLineItemAdjustmentDTO,
+  UpdateLineItemAdjustmentDTO,
+} from "@types"
+
+type InjectedDependencies = {
+  lineItemAdjustmentRepository: DAL.RepositoryService
+}
+
+export default class LineItemAdjustmentService<
+  TEntity extends LineItemAdjustment = LineItemAdjustment
+> extends ModulesSdkUtils.abstractServiceFactory<
+  InjectedDependencies,
+  {
+    create: CreateLineItemAdjustmentDTO
+    update: UpdateLineItemAdjustmentDTO
+  }
+>(LineItemAdjustment)<TEntity> {
+  constructor(container: InjectedDependencies) {
+    // @ts-ignore
+    super(...arguments)
+  }
+}

packages/cart/src/types/cart.ts

@@ -1,3 +1,8 @@
+import {
+  CreateLineItemAdjustmentDTO,
+  UpdateLineItemAdjustmentDTO,
+} from "./line-item-adjustment"
+
 export interface CreateCartDTO {
   region_id?: string
   customer_id?: string
@@ -15,4 +20,6 @@ export interface UpdateCartDTO {
   email?: string
   currency_code?: string
   metadata?: Record<string, unknown>
+
+  adjustments?: (CreateLineItemAdjustmentDTO | UpdateLineItemAdjustmentDTO)[]
 }

packages/cart/src/types/index.ts

@@ -3,6 +3,7 @@ import { Logger } from "@medusajs/types"
 export * from "./address"
 export * from "./cart"
 export * from "./line-item"
+export * from "./line-item-adjustment"
 export * from "./shipping-method"
 export * from "./repositories"
 

packages/cart/src/types/line-item-adjustment.ts

@@ -0,0 +1,13 @@
+export interface CreateLineItemAdjustmentDTO {
+  item_id: string
+  amount: number
+  code?: string
+  description?: string
+  promotion_id?: string
+  provider_id?: string
+}
+
+export interface UpdateLineItemAdjustmentDTO
+  extends Partial<CreateLineItemAdjustmentDTO> {
+  id: string
+}

packages/cart/src/types/repositories.ts

@@ -1,8 +1,12 @@
 import { DAL } from "@medusajs/types"
-import { Cart, LineItem, ShippingMethod } from "@models"
+import { Cart, LineItem, LineItemAdjustment, ShippingMethod } from "@models"
 import { CreateAddressDTO, UpdateAddressDTO } from "./address"
 import { CreateCartDTO, UpdateCartDTO } from "./cart"
 import { CreateLineItemDTO, UpdateLineItemDTO } from "./line-item"
+import {
+  CreateLineItemAdjustmentDTO,
+  UpdateLineItemAdjustmentDTO,
+} from "./line-item-adjustment"
 import {
   CreateShippingMethodDTO,
   UpdateShippingMethodDTO,
@@ -48,3 +52,13 @@ export interface IShippingMethodRepository<
       update: UpdateShippingMethodDTO
     }
   > {}
+
+export interface ILineItemAdjustmentRepository<
+  TEntity extends LineItemAdjustment = LineItemAdjustment
+> extends DAL.RepositoryService<
+    TEntity,
+    {
+      create: CreateLineItemAdjustmentDTO
+      update: UpdateLineItemAdjustmentDTO
+    }
+  > {}

packages/types/src/cart/common.ts

@@ -9,11 +9,15 @@ export interface AdjustmentLineDTO {
   /**
    * The code of the adjustment line
    */
-  code: string
+  code?: string
   /**
    * The amount of the adjustment line
    */
   amount: number
+  /**
+   * The ID of the associated cart
+   */
+  cart_id: string
   /**
    * The description of the adjustment line
    */
@@ -43,11 +47,16 @@ export interface ShippingMethodAdjustmentLineDTO extends AdjustmentLineDTO {
   shipping_method: CartShippingMethodDTO
 }
 
-export interface LineItemAdjustmentLineDTO extends AdjustmentLineDTO {
+export interface LineItemAdjustmentDTO extends AdjustmentLineDTO {
+  /**
+   * The associated line item
+   * @expandable
+   */
+  item: CartLineItemDTO
   /**
    * The associated line item
    */
-  line_item: CartLineItemDTO
+  item_id: string
 }
 
 export interface TaxLineDTO {
@@ -340,7 +349,7 @@ export interface CartLineItemDTO {
    *
    * @expandable
    */
-  adjustments?: LineItemAdjustmentLineDTO[]
+  adjustments?: LineItemAdjustmentDTO[]
   /**
    * The associated cart.
    *
@@ -494,6 +503,13 @@ export interface FilterableLineItemProps
   product_id?: string | string[]
 }
 
+export interface FilterableLineItemAdjustmentProps
+  extends BaseFilterable<FilterableLineItemAdjustmentProps> {
+  id?: string | string[]
+  item_id?: string | string[]
+  promotion_id?: string | string[]
+  provider_id?: string | string[]
+}
 export interface FilterableShippingMethodProps
   extends BaseFilterable<FilterableShippingMethodProps> {
   id?: string | string[]

packages/types/src/cart/mutations.ts

@@ -1,5 +1,6 @@
 import { CartLineItemDTO } from "./common"
 
+/** ADDRESS START */
 export interface UpsertAddressDTO {
   customer_id?: string
   company?: string
@@ -21,6 +22,9 @@ export interface UpdateAddressDTO extends UpsertAddressDTO {
 
 export interface CreateAddressDTO extends UpsertAddressDTO {}
 
+/** ADDRESS END */
+
+/** CART START */
 export interface CreateCartDTO {
   region_id?: string
   customer_id?: string
@@ -54,6 +58,9 @@ export interface UpdateCartDTO {
   metadata?: Record<string, unknown>
 }
 
+/** CART END */
+
+/** TAXLINES START */
 export interface CreateTaxLineDTO {
   description?: string
   tax_rate_id?: string
@@ -62,14 +69,6 @@ export interface CreateTaxLineDTO {
   provider_id?: string
 }
 
-export interface CreateAdjustmentDTO {
-  code: string
-  amount: number
-  description?: string
-  promotion_id?: string
-  provider_id?: string
-}
-
 export interface UpdateTaxLineDTO {
   id: string
   description?: string
@@ -79,15 +78,48 @@ export interface UpdateTaxLineDTO {
   provider_id?: string
 }
 
+/** TAXLINES END */
+
+/** ADJUSTMENT START */
+export interface CreateAdjustmentDTO {
+  item_id: string
+  code?: string
+  amount: number
+  description?: string
+  promotion_id?: string
+  provider_id?: string
+}
+
 export interface UpdateAdjustmentDTO {
   id: string
   code?: string
+  amount: number
+  description?: string
+  promotion_id?: string
+  provider_id?: string
+}
+
+export interface CreateLineItemAdjustmentDTO extends CreateAdjustmentDTO {
+  item_id: string
+}
+
+export interface UpdateLineItemAdjustmentDTO extends UpdateAdjustmentDTO {
+  item_id: string
+}
+
+export interface UpsertLineItemAdjustmentDTO {
+  id?: string
+  item_id: string
+  code?: string
   amount?: number
   description?: string
   promotion_id?: string
   provider_id?: string
 }
 
+/** ADJUSTMENT START */
+
+/** LINE ITEMS START */
 export interface CreateLineItemDTO {
   title: string
   subtitle?: string
@@ -146,14 +178,23 @@ export interface UpdateLineItemDTO
   adjustments?: UpdateAdjustmentDTO[] | CreateAdjustmentDTO[]
 }
 
+/** LINE ITEMS END */
+
+/** SHIPPING METHODS START */
+
 export interface CreateShippingMethodDTO {
   name: string
-
   cart_id: string
-
   amount: number
   data?: Record<string, unknown>
+  tax_lines?: CreateTaxLineDTO[]
+  adjustments?: CreateAdjustmentDTO[]
+}
 
+export interface CreateShippingMethodForSingleCartDTO {
+  name: string
+  amount: number
+  data?: Record<string, unknown>
   tax_lines?: CreateTaxLineDTO[]
   adjustments?: CreateAdjustmentDTO[]
 }
@@ -161,10 +202,10 @@ export interface CreateShippingMethodDTO {
 export interface UpdateShippingMethodDTO {
   id: string
   name?: string
-
   amount?: number
   data?: Record<string, unknown>
-
   tax_lines?: UpdateTaxLineDTO[] | CreateTaxLineDTO[]
-  adjustments?: UpdateAdjustmentDTO[] | CreateAdjustmentDTO[]
+  adjustments?: CreateAdjustmentDTO[] | UpdateAdjustmentDTO[]
 }
+
+/** SHIPPING METHODS END */

packages/types/src/cart/service.ts

@@ -2,24 +2,29 @@ import { FindConfig } from "../common"
 import { IModuleService } from "../modules-sdk"
 import { Context } from "../shared-context"
 import {
-  CartAddressDTO,
-  CartDTO,
-  CartLineItemDTO,
-  CartShippingMethodDTO,
-  FilterableAddressProps,
-  FilterableCartProps,
-  FilterableShippingMethodProps,
+    CartAddressDTO,
+    CartDTO,
+    CartLineItemDTO,
+    CartShippingMethodDTO,
+    FilterableAddressProps,
+    FilterableCartProps,
+    FilterableLineItemAdjustmentProps,
+    FilterableLineItemProps,
+    FilterableShippingMethodProps,
+    LineItemAdjustmentDTO,
 } from "./common"
 import {
-  CreateAddressDTO,
-  CreateCartDTO,
-  CreateLineItemDTO,
-  CreateLineItemForCartDTO,
-  CreateShippingMethodDTO,
-  UpdateAddressDTO,
-  UpdateCartDTO,
-  UpdateLineItemDTO,
-  UpdateLineItemWithSelectorDTO,
+    CreateAddressDTO,
+    CreateAdjustmentDTO,
+    CreateCartDTO,
+    CreateLineItemDTO,
+    CreateLineItemForCartDTO,
+    CreateShippingMethodDTO,
+    UpdateAddressDTO,
+    UpdateCartDTO,
+    UpdateLineItemDTO,
+    UpdateLineItemWithSelectorDTO,
+    UpsertLineItemAdjustmentDTO
 } from "./mutations"
 
 export interface ICartModuleService extends IModuleService {
@@ -77,7 +82,19 @@ export interface ICartModuleService extends IModuleService {
   deleteAddresses(ids: string[], sharedContext?: Context): Promise<void>
   deleteAddresses(ids: string, sharedContext?: Context): Promise<void>
 
-  addLineItems(data: CreateLineItemForCartDTO): Promise<CartLineItemDTO>
+  retrieveLineItem(
+    itemId: string,
+    config?: FindConfig<CartLineItemDTO>,
+    sharedContext?: Context
+  ): Promise<CartLineItemDTO>
+
+  listLineItems(
+    filters: FilterableLineItemProps,
+    config?: FindConfig<CartLineItemDTO>,
+    sharedContext?: Context
+  ): Promise<CartLineItemDTO[]>
+
+  addLineItems(data: CreateLineItemForCartDTO): Promise<CartLineItemDTO[]>
   addLineItems(data: CreateLineItemForCartDTO[]): Promise<CartLineItemDTO[]>
   addLineItems(
     cartId: string,
@@ -136,4 +153,40 @@ export interface ICartModuleService extends IModuleService {
     selector: Partial<CartShippingMethodDTO>,
     sharedContext?: Context
   ): Promise<void>
+
+  listLineItemAdjustments(
+    filters: FilterableLineItemAdjustmentProps,
+    config?: FindConfig<LineItemAdjustmentDTO>,
+    sharedContext?: Context
+  ): Promise<LineItemAdjustmentDTO[]>
+
+  addLineItemAdjustments(
+    data: CreateAdjustmentDTO[]
+  ): Promise<LineItemAdjustmentDTO[]>
+  addLineItemAdjustments(
+    data: CreateAdjustmentDTO
+  ): Promise<LineItemAdjustmentDTO[]>
+  addLineItemAdjustments(
+    cartId: string,
+    data: CreateAdjustmentDTO[]
+  ): Promise<LineItemAdjustmentDTO[]>
+
+  setLineItemAdjustments(
+    cartId: string,
+    data: UpsertLineItemAdjustmentDTO[],
+    sharedContext?: Context
+  ): Promise<LineItemAdjustmentDTO[]>
+
+  removeLineItemAdjustments(
+    adjustmentIds: string[],
+    sharedContext?: Context
+  ): Promise<void>
+  removeLineItemAdjustments(
+    adjustmentIds: string,
+    sharedContext?: Context
+  ): Promise<void>
+  removeLineItemAdjustments(
+    selector: Partial<LineItemAdjustmentDTO>,
+    sharedContext?: Context
+  ): Promise<void>
 }

packages/utils/src/modules-sdk/abstract-service-factory.ts

@@ -1,16 +1,16 @@
 import {
   Context,
-  FilterQuery as InternalFilterQuery,
   FindConfig,
+  FilterQuery as InternalFilterQuery,
 } from "@medusajs/types"
 import { EntitySchema } from "@mikro-orm/core"
 import { EntityClass } from "@mikro-orm/core/typings"
 import {
+  MedusaError,
   doNotForceTransaction,
   isDefined,
   isString,
   lowerCaseFirst,
-  MedusaError,
   shouldForceTransaction,
   upperCaseFirst,
 } from "../common"