From a5e8bf06c63301dc001bbd3fc972633da12d7821 Mon Sep 17 00:00:00 2001
From: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>
Date: Tue, 16 Jan 2024 15:44:49 +0100
Subject: [PATCH] feat(cart): Line items operations (#6066)

---
 .../services/cart-module/index.spec.ts        | 367 ++++++++++++++++-
 packages/cart/src/loaders/container.ts        |   2 +
 packages/cart/src/models/cart.ts              |   3 +-
 packages/cart/src/models/line-item.ts         |  20 +-
 packages/cart/src/repositories/address.ts     |  25 +-
 packages/cart/src/repositories/index.ts       |   1 +
 packages/cart/src/repositories/line-item.ts   |  11 +
 packages/cart/src/services/address.ts         |   7 +-
 packages/cart/src/services/cart-module.ts     | 383 +++++++++++++++---
 packages/cart/src/services/index.ts           |   1 +
 packages/cart/src/services/line-item.ts       | 128 ++++++
 packages/cart/src/types/index.ts              |   1 +
 packages/cart/src/types/line-item.ts          |  37 ++
 .../src/handlers/cart/create-cart.ts          |   4 +-
 .../src/handlers/cart/retrieve-cart.ts        |   4 +-
 packages/types/src/cart/common.ts             |  22 +-
 packages/types/src/cart/mutations.ts          |  38 +-
 packages/types/src/cart/service.ts            |  55 ++-
 18 files changed, 973 insertions(+), 136 deletions(-)
 create mode 100644 packages/cart/src/repositories/line-item.ts
 create mode 100644 packages/cart/src/services/line-item.ts
 create mode 100644 packages/cart/src/types/line-item.ts

diff --git a/packages/cart/integration-tests/__tests__/services/cart-module/index.spec.ts b/packages/cart/integration-tests/__tests__/services/cart-module/index.spec.ts
index 151343e1d1..acbdd99435 100644
--- a/packages/cart/integration-tests/__tests__/services/cart-module/index.spec.ts
+++ b/packages/cart/integration-tests/__tests__/services/cart-module/index.spec.ts
@@ -1,5 +1,4 @@
 import { ICartModuleService } from "@medusajs/types"
-import { SqlEntityManager } from "@mikro-orm/postgresql"
 import { initialize } from "../../../../src/initialize"
 import { DB_URL, MikroOrmWrapper } from "../../../utils"
 
@@ -7,11 +6,9 @@ jest.setTimeout(30000)
 
 describe("Cart Module Service", () => {
   let service: ICartModuleService
-  let repositoryManager: SqlEntityManager
 
   beforeEach(async () => {
     await MikroOrmWrapper.setupDatabase()
-    repositoryManager = await MikroOrmWrapper.forkManager()
 
     service = await initialize({
       database: {
@@ -242,4 +239,368 @@ describe("Cart Module Service", () => {
       expect(address).toBe(undefined)
     })
   })
+
+  describe("addLineItems", () => {
+    it("should add a line item to cart succesfully", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const items = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const cart = await service.retrieve(createdCart.id, {
+        relations: ["items"],
+      })
+
+      expect(items[0]).toEqual(
+        expect.objectContaining({
+          title: "test",
+          quantity: 1,
+          unit_price: 100,
+        })
+      )
+      expect(cart.items?.length).toBe(1)
+    })
+
+    it("should add multiple line items to cart succesfully", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      await service.addLineItems([
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+          cart_id: createdCart.id,
+        },
+        {
+          quantity: 2,
+          unit_price: 200,
+          title: "test-2",
+          cart_id: createdCart.id,
+        },
+      ])
+
+      const cart = await service.retrieve(createdCart.id, {
+        relations: ["items"],
+      })
+
+      expect(cart.items).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            title: "test",
+            quantity: 1,
+            unit_price: 100,
+          }),
+          expect.objectContaining({
+            title: "test-2",
+            quantity: 2,
+            unit_price: 200,
+          }),
+        ])
+      )
+
+      expect(cart.items?.length).toBe(2)
+    })
+
+    it("should add multiple line items to multiple carts succesfully", async () => {
+      let [eurCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      let [usdCart] = await service.create([
+        {
+          currency_code: "usd",
+        },
+      ])
+
+      const items = await service.addLineItems([
+        {
+          cart_id: eurCart.id,
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+        {
+          cart_id: usdCart.id,
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+      ])
+
+      const carts = await service.list(
+        { id: [eurCart.id, usdCart.id] },
+        { relations: ["items"] }
+      )
+
+      eurCart = carts.find((c) => c.currency_code === "eur")!
+      usdCart = carts.find((c) => c.currency_code === "usd")!
+
+      const eurItems = items.filter((i) => i.cart_id === eurCart.id)
+      const usdItems = items.filter((i) => i.cart_id === usdCart.id)
+
+      expect(eurCart.items![0].id).toBe(eurItems[0].id)
+      expect(usdCart.items![0].id).toBe(usdItems[0].id)
+
+      expect(eurCart.items?.length).toBe(1)
+      expect(usdCart.items?.length).toBe(1)
+    })
+
+    it("should throw if cart does not exist", async () => {
+      const error = await service
+        .addLineItems("foo", [
+          {
+            quantity: 1,
+            unit_price: 100,
+            title: "test",
+            tax_lines: [],
+          },
+        ])
+        .catch((e) => e)
+
+      expect(error.message).toContain("Cart with id: foo was not found")
+    })
+
+    it("should throw an error when required params are not passed adding to a single cart", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const error = await service
+        .addLineItems(createdCart.id, [
+          {
+            quantity: 1,
+            title: "test",
+          },
+        ] as any)
+        .catch((e) => e)
+
+      expect(error.message).toContain(
+        "Value for LineItem.unit_price is required, 'undefined' found"
+      )
+    })
+
+    it("should throw a generic error when required params are not passed using bulk add method", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const error = await service
+        .addLineItems([
+          {
+            cart_id: createdCart.id,
+            quantity: 1,
+            title: "test",
+          },
+        ] as any)
+        .catch((e) => e)
+
+      expect(error.message).toContain(
+        "Value for LineItem.unit_price is required, 'undefined' found"
+      )
+    })
+  })
+
+  describe("updateLineItems", () => {
+    it("should update a line item in cart succesfully with selector approach", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [item] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+          tax_lines: [],
+        },
+      ])
+
+      expect(item.title).toBe("test")
+
+      const [updatedItem] = await service.updateLineItems(
+        { cart_id: createdCart.id },
+        {
+          title: "test2",
+        }
+      )
+
+      expect(updatedItem.title).toBe("test2")
+    })
+
+    it("should update a line item in cart succesfully with id approach", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [item] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+          tax_lines: [],
+        },
+      ])
+
+      expect(item.title).toBe("test")
+
+      const updatedItem = await service.updateLineItems(
+        item.id,
+        {
+          title: "test2",
+        }
+      )
+
+      expect(updatedItem.title).toBe("test2")
+    })
+
+    it("should update line items in carts succesfully with multi-selector approach", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const items = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+        {
+          quantity: 2,
+          unit_price: 200,
+          title: "other-test",
+        },
+      ])
+
+      expect(items).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            title: "test",
+            quantity: 1,
+            unit_price: 100,
+          }),
+          expect.objectContaining({
+            title: "other-test",
+            quantity: 2,
+            unit_price: 200,
+          }),
+        ])
+      )
+
+      const itemOne = items.find((i) => i.title === "test")
+      const itemTwo = items.find((i) => i.title === "other-test")
+
+      const updatedItems = await service.updateLineItems([
+        {
+          selector: { cart_id: createdCart.id },
+          data: {
+            title: "changed-test",
+          }
+        },
+        {
+          selector: { id: itemTwo!.id },
+          data: {
+            title: "changed-other-test",
+          }
+        },
+      ])
+
+      expect(updatedItems).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({
+            title: "changed-test",
+            quantity: 1,
+            unit_price: 100,
+          }),
+          expect.objectContaining({
+            title: "changed-other-test",
+            quantity: 2,
+            unit_price: 200,
+          }),
+        ])
+      )
+    })
+  })
+
+  describe("removeLineItems", () => {
+    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",
+          tax_lines: [],
+        },
+      ])
+
+      expect(item.title).toBe("test")
+
+      await service.removeLineItems([item.id])
+
+      const cart = await service.retrieve(createdCart.id, {
+        relations: ["items"],
+      })
+
+      expect(cart.items?.length).toBe(0)
+    })
+
+    it("should remove multiple line items succesfully", async () => {
+      const [createdCart] = await service.create([
+        {
+          currency_code: "eur",
+        },
+      ])
+
+      const [item, item2] = await service.addLineItems(createdCart.id, [
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test",
+        },
+        {
+          quantity: 1,
+          unit_price: 100,
+          title: "test-2",
+        },
+      ])
+
+      await service.removeLineItems([item.id, item2.id])
+
+      const cart = await service.retrieve(createdCart.id, {
+        relations: ["items"],
+      })
+
+      expect(cart.items?.length).toBe(0)
+    })
+  })
 })
diff --git a/packages/cart/src/loaders/container.ts b/packages/cart/src/loaders/container.ts
index a8716ea5ab..ae8a1be50e 100644
--- a/packages/cart/src/loaders/container.ts
+++ b/packages/cart/src/loaders/container.ts
@@ -20,6 +20,7 @@ export default async ({
   container.register({
     cartService: asClass(defaultServices.CartService).singleton(),
     addressService: asClass(defaultServices.AddressService).singleton(),
+    lineItemService: asClass(defaultServices.LineItemService).singleton(),
   })
 
   if (customRepositories) {
@@ -38,5 +39,6 @@ function loadDefaultRepositories({ container }) {
     baseRepository: asClass(defaultRepositories.BaseRepository).singleton(),
     cartRepository: asClass(defaultRepositories.CartRepository).singleton(),
     addressRepository: asClass(defaultRepositories.AddressRepository).singleton(),
+    lineItemRepository: asClass(defaultRepositories.LineItemRepository).singleton(),
   })
 }
diff --git a/packages/cart/src/models/cart.ts b/packages/cart/src/models/cart.ts
index 2dfc02aab4..168f9216ba 100644
--- a/packages/cart/src/models/cart.ts
+++ b/packages/cart/src/models/cart.ts
@@ -11,7 +11,7 @@ import {
   OneToMany,
   OptionalProps,
   PrimaryKey,
-  Property,
+  Property
 } from "@mikro-orm/core"
 import Address from "./address"
 import LineItem from "./line-item"
@@ -78,7 +78,6 @@ export default class Cart {
 
   @OneToMany(() => ShippingMethod, (shippingMethod) => shippingMethod.cart, {
     cascade: [Cascade.REMOVE],
-    
   })
   shipping_methods = new Collection<ShippingMethod>(this)
 
diff --git a/packages/cart/src/models/line-item.ts b/packages/cart/src/models/line-item.ts
index 4480e0877a..da54c7046d 100644
--- a/packages/cart/src/models/line-item.ts
+++ b/packages/cart/src/models/line-item.ts
@@ -22,6 +22,7 @@ type OptionalLineItemProps =
   | "is_tax_inclusive"
   | "compare_at_unit_price"
   | "requires_shipping"
+  | "cart"
   | DAL.EntityDateColumns
 
 @Entity({ tableName: "cart_line_item" })
@@ -31,12 +32,15 @@ export default class LineItem {
   @PrimaryKey({ columnType: "text" })
   id: string
 
+  @Property({ columnType: "text" })
+  cart_id: string
+
   @ManyToOne(() => Cart, {
     onDelete: "cascade",
     index: "IDX_line_item_cart_id",
-    fieldName: "cart_id",
+    nullable: true,
   })
-  cart!: Cart
+  cart?: Cart | null
 
   @Property({ columnType: "text" })
   title: string
@@ -47,7 +51,7 @@ export default class LineItem {
   @Property({ columnType: "text", nullable: true })
   thumbnail?: string | null
 
-  @Property({ columnType: "text" })
+  @Property({ columnType: "integer" })
   quantity: number
 
   @Property({
@@ -90,13 +94,13 @@ export default class LineItem {
   @Property({ columnType: "jsonb", nullable: true })
   variant_option_values?: Record<string, unknown> | null
 
-  @Property({ columnType: "boolean" })
+  @Property({ columnType: "boolean", default: true })
   requires_shipping = true
 
-  @Property({ columnType: "boolean" })
+  @Property({ columnType: "boolean", default: true })
   is_discountable = true
 
-  @Property({ columnType: "boolean" })
+  @Property({ columnType: "boolean", default: false })
   is_tax_inclusive = false
 
   @Property({ columnType: "numeric", nullable: true })
@@ -147,7 +151,7 @@ export default class LineItem {
     columnType: "timestamptz",
     defaultRaw: "now()",
   })
-  created_at: Date
+  created_at?: Date
 
   @Property({
     onCreate: () => new Date(),
@@ -155,7 +159,7 @@ export default class LineItem {
     columnType: "timestamptz",
     defaultRaw: "now()",
   })
-  updated_at: Date
+  updated_at?: Date
 
   @BeforeCreate()
   onCreate() {
diff --git a/packages/cart/src/repositories/address.ts b/packages/cart/src/repositories/address.ts
index 53c375821e..a480877948 100644
--- a/packages/cart/src/repositories/address.ts
+++ b/packages/cart/src/repositories/address.ts
@@ -1,6 +1,4 @@
-import { Context } from "@medusajs/types"
 import { DALUtils } from "@medusajs/utils"
-import { SqlEntityManager } from "@mikro-orm/postgresql"
 import { Address } from "@models"
 import { CreateAddressDTO, UpdateAddressDTO } from "../types"
 
@@ -8,25 +6,6 @@ export class AddressRepository extends DALUtils.mikroOrmBaseRepositoryFactory<
   Address,
   {
     create: CreateAddressDTO
+    update: UpdateAddressDTO
   }
->(Address) {
-  constructor(...args: any[]) {
-    // @ts-ignore
-    super(...arguments)
-  }
-
-  async update(
-    data: { address: Address; update: UpdateAddressDTO }[],
-    context: Context = {}
-  ): Promise<Address[]> {
-    const manager = this.getActiveManager<SqlEntityManager>(context)
-
-    const entities = data.map(({ address, update }) => {
-      return manager.assign(address, update)
-    })
-
-    manager.persist(entities)
-
-    return entities
-  }
-}
+>(Address) {}
diff --git a/packages/cart/src/repositories/index.ts b/packages/cart/src/repositories/index.ts
index d527e6f73c..fabd202b2d 100644
--- a/packages/cart/src/repositories/index.ts
+++ b/packages/cart/src/repositories/index.ts
@@ -1,4 +1,5 @@
 export { MikroOrmBaseRepository as BaseRepository } from "@medusajs/utils"
 export * from "./address"
 export * from "./cart"
+export * from "./line-item"
 
diff --git a/packages/cart/src/repositories/line-item.ts b/packages/cart/src/repositories/line-item.ts
new file mode 100644
index 0000000000..6741e7ee89
--- /dev/null
+++ b/packages/cart/src/repositories/line-item.ts
@@ -0,0 +1,11 @@
+import { DALUtils } from "@medusajs/utils"
+import { LineItem } from "@models"
+import { CreateLineItemDTO, UpdateLineItemDTO } from "../types"
+
+export class LineItemRepository extends DALUtils.mikroOrmBaseRepositoryFactory<
+  LineItem,
+  {
+    create: CreateLineItemDTO
+    update: UpdateLineItemDTO
+  }
+>(LineItem) {}
diff --git a/packages/cart/src/services/address.ts b/packages/cart/src/services/address.ts
index 24484662fe..0e4e17d2cf 100644
--- a/packages/cart/src/services/address.ts
+++ b/packages/cart/src/services/address.ts
@@ -1,5 +1,6 @@
 import {
   AddressDTO,
+  CartAddressDTO,
   Context,
   DAL,
   FilterableAddressProps,
@@ -46,7 +47,7 @@ export default class AddressService<TEntity extends Address = Address> {
   @InjectManager("addressRepository_")
   async list(
     filters: FilterableAddressProps = {},
-    config: FindConfig<AddressDTO> = {},
+    config: FindConfig<CartAddressDTO> = {},
     @MedusaContext() sharedContext: Context = {}
   ): Promise<TEntity[]> {
     const queryOptions = ModulesSdkUtils.buildQuery<Address>(filters, config)
@@ -97,7 +98,7 @@ export default class AddressService<TEntity extends Address = Address> {
       existingAddresses.map<[string, Address]>((addr) => [addr.id, addr])
     )
 
-    const updates: { address: Address; update: UpdateAddressDTO }[] = []
+    const updates: UpdateAddressDTO[] = []
 
     for (const update of data) {
       const address = existingAddressesMap.get(update.id)
@@ -109,7 +110,7 @@ export default class AddressService<TEntity extends Address = Address> {
         )
       }
 
-      updates.push({ address, update })
+      updates.push({ ...update, id: address.id })
     }
 
     return (await (this.addressRepository_ as AddressRepository).update(
diff --git a/packages/cart/src/services/cart-module.ts b/packages/cart/src/services/cart-module.ts
index 419c71b84f..5a20a5e9ea 100644
--- a/packages/cart/src/services/cart-module.ts
+++ b/packages/cart/src/services/cart-module.ts
@@ -1,47 +1,53 @@
 import {
-  AddressDTO,
-  CartAddressDTO,
-  CartDTO,
   Context,
-  CreateCartDTO,
   DAL,
   FilterableCartProps,
   FindConfig,
   ICartModuleService,
   InternalModuleDeclaration,
   ModuleJoinerConfig,
-  UpdateCartDTO,
 } from "@medusajs/types"
 
-import { FilterableAddressProps } from "@medusajs/types"
+import { CartTypes } from "@medusajs/types"
+
 import {
   InjectManager,
   InjectTransactionManager,
   MedusaContext,
+  isObject,
+  isString,
 } from "@medusajs/utils"
-import { CreateAddressDTO, UpdateAddressDTO } from "@types"
+import { LineItem } from "@models"
+import { UpdateLineItemDTO } from "@types"
 import { joinerConfig } from "../joiner-config"
-import AddressService from "./address"
-import CartService from "./cart"
+import * as services from "../services"
 
 type InjectedDependencies = {
   baseRepository: DAL.RepositoryService
-  cartService: CartService
-  addressService: AddressService
+  cartService: services.CartService
+  addressService: services.AddressService
+  lineItemService: services.LineItemService
 }
 
 export default class CartModuleService implements ICartModuleService {
   protected baseRepository_: DAL.RepositoryService
-  protected cartService_: CartService
-  protected addressService_: AddressService
+  protected cartService_: services.CartService
+  protected addressService_: services.AddressService
+  protected lineItemService_: services.LineItemService
 
   constructor(
-    { baseRepository, cartService, addressService }: InjectedDependencies,
+    {
+      baseRepository,
+      cartService,
+      addressService,
+      lineItemService,
+    }: InjectedDependencies,
     protected readonly moduleDeclaration: InternalModuleDeclaration
   ) {
     this.baseRepository_ = baseRepository
     this.cartService_ = cartService
     this.addressService_ = addressService
+    this.lineItemService_ = lineItemService
   }
 
   __joinerConfig(): ModuleJoinerConfig {
@@ -51,25 +57,25 @@ export default class CartModuleService implements ICartModuleService {
   @InjectManager("baseRepository_")
   async retrieve(
     id: string,
-    config: FindConfig<CartDTO> = {},
+    config: FindConfig<CartTypes.CartDTO> = {},
     @MedusaContext() sharedContext: Context = {}
-  ): Promise<CartDTO> {
+  ): Promise<CartTypes.CartDTO> {
     const cart = await this.cartService_.retrieve(id, config, sharedContext)
 
-    return await this.baseRepository_.serialize<CartDTO>(cart, {
+    return await this.baseRepository_.serialize<CartTypes.CartDTO>(cart, {
       populate: true,
     })
   }
 
   @InjectManager("baseRepository_")
   async list(
-    filters: FilterableCartProps = {},
-    config: FindConfig<CartDTO> = {},
+    filters: CartTypes.FilterableCartProps = {},
+    config: FindConfig<CartTypes.CartDTO> = {},
     @MedusaContext() sharedContext: Context = {}
-  ): Promise<CartDTO[]> {
+  ): Promise<CartTypes.CartDTO[]> {
     const carts = await this.cartService_.list(filters, config, sharedContext)
 
-    return await this.baseRepository_.serialize<CartDTO[]>(carts, {
+    return this.baseRepository_.serialize<CartTypes.CartDTO[]>(carts, {
       populate: true,
     })
   }
@@ -77,9 +83,9 @@ export default class CartModuleService implements ICartModuleService {
   @InjectManager("baseRepository_")
   async listAndCount(
     filters: FilterableCartProps = {},
-    config: FindConfig<CartDTO> = {},
+    config: FindConfig<CartTypes.CartDTO> = {},
     @MedusaContext() sharedContext: Context = {}
-  ): Promise<[CartDTO[], number]> {
+  ): Promise<[CartTypes.CartDTO[], number]> {
     const [carts, count] = await this.cartService_.listAndCount(
       filters,
       config,
@@ -87,7 +93,7 @@ export default class CartModuleService implements ICartModuleService {
     )
 
     return [
-      await this.baseRepository_.serialize<CartDTO[]>(carts, {
+      await this.baseRepository_.serialize<CartTypes.CartDTO[]>(carts, {
         populate: true,
       }),
       count,
@@ -95,17 +101,20 @@ export default class CartModuleService implements ICartModuleService {
   }
 
   async create(
-    data: CreateCartDTO[],
+    data: CartTypes.CreateCartDTO[],
     sharedContext?: Context
-  ): Promise<CartDTO[]>
+  ): Promise<CartTypes.CartDTO[]>
 
-  async create(data: CreateCartDTO, sharedContext?: Context): Promise<CartDTO>
+  async create(
+    data: CartTypes.CreateCartDTO,
+    sharedContext?: Context
+  ): Promise<CartTypes.CartDTO>
 
   @InjectManager("baseRepository_")
   async create(
-    data: CreateCartDTO[] | CreateCartDTO,
+    data: CartTypes.CreateCartDTO[] | CartTypes.CreateCartDTO,
     @MedusaContext() sharedContext: Context = {}
-  ): Promise<CartDTO[] | CartDTO> {
+  ): Promise<CartTypes.CartDTO[] | CartTypes.CartDTO> {
     const input = Array.isArray(data) ? data : [data]
 
     const carts = await this.create_(input, sharedContext)
@@ -118,29 +127,34 @@ export default class CartModuleService implements ICartModuleService {
       sharedContext
     )
 
-    return (Array.isArray(data) ? result : result[0]) as CartDTO | CartDTO[]
+    return (Array.isArray(data) ? result : result[0]) as
+      | CartTypes.CartDTO
+      | CartTypes.CartDTO[]
   }
 
   @InjectTransactionManager("baseRepository_")
   protected async create_(
-    data: CreateCartDTO[],
+    data: CartTypes.CreateCartDTO[],
     @MedusaContext() sharedContext: Context = {}
   ) {
     return await this.cartService_.create(data, sharedContext)
   }
 
   async update(
-    data: UpdateCartDTO[],
+    data: CartTypes.UpdateCartDTO[],
     sharedContext?: Context
-  ): Promise<CartDTO[]>
+  ): Promise<CartTypes.CartDTO[]>
 
-  async update(data: UpdateCartDTO, sharedContext?: Context): Promise<CartDTO>
+  async update(
+    data: CartTypes.UpdateCartDTO,
+    sharedContext?: Context
+  ): Promise<CartTypes.CartDTO>
 
   @InjectManager("baseRepository_")
   async update(
-    data: UpdateCartDTO[] | UpdateCartDTO,
+    data: CartTypes.UpdateCartDTO[] | CartTypes.UpdateCartDTO,
     @MedusaContext() sharedContext: Context = {}
-  ): Promise<CartDTO[] | CartDTO> {
+  ): Promise<CartTypes.CartDTO[] | CartTypes.CartDTO> {
     const input = Array.isArray(data) ? data : [data]
     const carts = await this.update_(input, sharedContext)
 
@@ -152,12 +166,14 @@ export default class CartModuleService implements ICartModuleService {
       sharedContext
     )
 
-    return (Array.isArray(data) ? result : result[0]) as CartDTO | CartDTO[]
+    return (Array.isArray(data) ? result : result[0]) as
+      | CartTypes.CartDTO
+      | CartTypes.CartDTO[]
   }
 
   @InjectTransactionManager("baseRepository_")
   protected async update_(
-    data: UpdateCartDTO[],
+    data: CartTypes.UpdateCartDTO[],
     @MedusaContext() sharedContext: Context = {}
   ) {
     return await this.cartService_.update(data, sharedContext)
@@ -178,8 +194,8 @@ export default class CartModuleService implements ICartModuleService {
 
   @InjectManager("baseRepository_")
   async listAddresses(
-    filters: FilterableAddressProps = {},
-    config: FindConfig<AddressDTO> = {},
+    filters: CartTypes.FilterableAddressProps = {},
+    config: FindConfig<CartTypes.CartAddressDTO> = {},
     @MedusaContext() sharedContext: Context = {}
   ) {
     const addresses = await this.addressService_.list(
@@ -188,19 +204,260 @@ export default class CartModuleService implements ICartModuleService {
       sharedContext
     )
 
-    return await this.baseRepository_.serialize<CartAddressDTO[]>(addresses, {
-      populate: true,
-    })
+    return await this.baseRepository_.serialize<CartTypes.CartAddressDTO[]>(
+      addresses,
+      {
+        populate: true,
+      }
+    )
   }
 
-  async createAddresses(data: CreateAddressDTO, sharedContext?: Context)
-  async createAddresses(data: CreateAddressDTO[], sharedContext?: Context)
+  @InjectManager("baseRepository_")
+  async retrieveLineItem(
+    itemId: string,
+    config: FindConfig<CartTypes.CartLineItemDTO> = {},
+    @MedusaContext() sharedContext: Context = {}
+  ) {
+    const item = await this.lineItemService_.retrieve(
+      itemId,
+      config,
+      sharedContext
+    )
+
+    return await this.baseRepository_.serialize<CartTypes.CartLineItemDTO[]>(
+      item,
+      {
+        populate: true,
+      }
+    )
+  }
+
+  @InjectManager("baseRepository_")
+  async listLineItems(
+    filters: CartTypes.FilterableLineItemProps = {},
+    config: FindConfig<CartTypes.CartLineItemDTO> = {},
+    @MedusaContext() sharedContext: Context = {}
+  ) {
+    const items = await this.lineItemService_.list(
+      filters,
+      config,
+      sharedContext
+    )
+
+    return await this.baseRepository_.serialize<CartTypes.CartLineItemDTO[]>(
+      items,
+      {
+        populate: true,
+      }
+    )
+  }
+
+  addLineItems(
+    data: CartTypes.CreateLineItemForCartDTO
+  ): Promise<CartTypes.CartLineItemDTO>
+  addLineItems(
+    data: CartTypes.CreateLineItemForCartDTO[]
+  ): Promise<CartTypes.CartLineItemDTO[]>
+  addLineItems(
+    cartId: string,
+    items: CartTypes.CreateLineItemDTO[],
+    sharedContext?: Context
+  ): Promise<CartTypes.CartLineItemDTO[]>
+
+  @InjectManager("baseRepository_")
+  async addLineItems(
+    cartIdOrData:
+      | string
+      | CartTypes.CreateLineItemForCartDTO[]
+      | CartTypes.CreateLineItemForCartDTO,
+    data?: CartTypes.CreateLineItemDTO[] | CartTypes.CreateLineItemDTO,
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<CartTypes.CartLineItemDTO[] | CartTypes.CartLineItemDTO> {
+    let items: LineItem[] = []
+    if (isString(cartIdOrData)) {
+      items = await this.addLineItems_(
+        cartIdOrData,
+        data as CartTypes.CreateLineItemDTO[],
+        sharedContext
+      )
+    } else {
+      const data = Array.isArray(cartIdOrData) ? cartIdOrData : [cartIdOrData]
+      items = await this.addLineItemsBulk_(data, sharedContext)
+    }
+
+    return await this.baseRepository_.serialize<CartTypes.CartLineItemDTO[]>(
+      items,
+      {
+        populate: true,
+      }
+    )
+  }
+
+  @InjectTransactionManager("baseRepository_")
+  protected async addLineItems_(
+    cartId: string,
+    items: CartTypes.CreateLineItemDTO[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<LineItem[]> {
+    const cart = await this.retrieve(cartId, { select: ["id"] }, sharedContext)
+
+    const toUpdate = items.map((item) => {
+      return {
+        ...item,
+        cart_id: cart.id,
+      }
+    })
+
+    return await this.addLineItemsBulk_(toUpdate, sharedContext)
+  }
+
+  @InjectTransactionManager("baseRepository_")
+  protected async addLineItemsBulk_(
+    data: CartTypes.CreateLineItemForCartDTO[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<LineItem[]> {
+    return await this.lineItemService_.create(data, sharedContext)
+  }
+
+  updateLineItems(
+    data: CartTypes.UpdateLineItemWithSelectorDTO[]
+  ): Promise<CartTypes.CartLineItemDTO[]>
+  updateLineItems(
+    selector: Partial<CartTypes.CartLineItemDTO>,
+    data: CartTypes.UpdateLineItemDTO,
+    sharedContext?: Context
+  ): Promise<CartTypes.CartLineItemDTO[]>
+  updateLineItems(
+    lineItemId: string,
+    data: Partial<CartTypes.UpdateLineItemDTO>,
+    sharedContext?: Context
+  ): Promise<CartTypes.CartLineItemDTO>
+
+  @InjectManager("baseRepository_")
+  async updateLineItems(
+    lineItemIdOrDataOrSelector:
+      | string
+      | CartTypes.UpdateLineItemWithSelectorDTO[]
+      | Partial<CartTypes.CartLineItemDTO>,
+    data?: CartTypes.UpdateLineItemDTO | Partial<CartTypes.UpdateLineItemDTO>,
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<CartTypes.CartLineItemDTO[] | CartTypes.CartLineItemDTO> {
+    let items: LineItem[] = []
+    if (isString(lineItemIdOrDataOrSelector)) {
+      const item = await this.updateLineItem_(
+        lineItemIdOrDataOrSelector,
+        data as Partial<CartTypes.UpdateLineItemDTO>,
+        sharedContext
+      )
+
+      return await this.baseRepository_.serialize<CartTypes.CartLineItemDTO>(
+        item,
+        {
+          populate: true,
+        }
+      )
+    }
+
+    const toUpdate = Array.isArray(lineItemIdOrDataOrSelector)
+      ? lineItemIdOrDataOrSelector
+      : [
+          {
+            selector: lineItemIdOrDataOrSelector,
+            data: data,
+          } as CartTypes.UpdateLineItemWithSelectorDTO,
+        ]
+
+    items = await this.updateLineItemsWithSelector_(toUpdate, sharedContext)
+
+    return await this.baseRepository_.serialize<CartTypes.CartLineItemDTO[]>(
+      items,
+      {
+        populate: true,
+      }
+    )
+  }
+
+  @InjectTransactionManager("baseRepository_")
+  protected async updateLineItem_(
+    lineItemId: string,
+    data: Partial<CartTypes.UpdateLineItemDTO>,
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<LineItem> {
+    const [item] = await this.lineItemService_.update(
+      [{ id: lineItemId, ...data }],
+      sharedContext
+    )
+
+    return item
+  }
+
+  @InjectTransactionManager("baseRepository_")
+  protected async updateLineItemsWithSelector_(
+    updates: CartTypes.UpdateLineItemWithSelectorDTO[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<LineItem[]> {
+    let toUpdate: UpdateLineItemDTO[] = []
+    for (const { selector, data } of updates) {
+      const items = await this.listLineItems({ ...selector }, {}, sharedContext)
+
+      items.forEach((item) => {
+        toUpdate.push({
+          ...data,
+          id: item.id,
+        })
+      })
+    }
+
+    return await this.lineItemService_.update(toUpdate, sharedContext)
+  }
+
+  async removeLineItems(
+    itemIds: string[],
+    sharedContext?: Context
+  ): Promise<void>
+  async removeLineItems(itemIds: string, sharedContext?: Context): Promise<void>
+  async removeLineItems(
+    selector: Partial<CartTypes.CartLineItemDTO>,
+    sharedContext?: Context
+  ): Promise<void>
+
+  @InjectTransactionManager("baseRepository_")
+  async removeLineItems(
+    itemIdsOrSelector: string | string[] | Partial<CartTypes.CartLineItemDTO>,
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<void> {
+    let toDelete: string[] = []
+    if (isObject(itemIdsOrSelector)) {
+      const items = await this.listLineItems(
+        { ...itemIdsOrSelector } as Partial<CartTypes.CartLineItemDTO>,
+        {},
+        sharedContext
+      )
+
+      toDelete = items.map((item) => item.id)
+    } else {
+      toDelete = Array.isArray(itemIdsOrSelector)
+        ? itemIdsOrSelector
+        : [itemIdsOrSelector]
+    }
+
+    await this.lineItemService_.delete(toDelete, sharedContext)
+  }
+
+  async createAddresses(
+    data: CartTypes.CreateAddressDTO,
+    sharedContext?: Context
+  ): Promise<CartTypes.CartAddressDTO>
+  async createAddresses(
+    data: CartTypes.CreateAddressDTO[],
+    sharedContext?: Context
+  ): Promise<CartTypes.CartAddressDTO[]>
 
   @InjectManager("baseRepository_")
   async createAddresses(
-    data: CreateAddressDTO[] | CreateAddressDTO,
+    data: CartTypes.CreateAddressDTO[] | CartTypes.CreateAddressDTO,
     @MedusaContext() sharedContext: Context = {}
-  ) {
+  ): Promise<CartTypes.CartAddressDTO | CartTypes.CartAddressDTO[]> {
     const input = Array.isArray(data) ? data : [data]
     const addresses = await this.createAddresses_(input, sharedContext)
 
@@ -211,26 +468,32 @@ export default class CartModuleService implements ICartModuleService {
     )
 
     return (Array.isArray(data) ? result : result[0]) as
-      | AddressDTO
-      | AddressDTO[]
+      | CartTypes.CartAddressDTO
+      | CartTypes.CartAddressDTO[]
   }
 
   @InjectTransactionManager("baseRepository_")
   protected async createAddresses_(
-    data: CreateAddressDTO[],
+    data: CartTypes.CreateAddressDTO[],
     @MedusaContext() sharedContext: Context = {}
   ) {
     return await this.addressService_.create(data, sharedContext)
   }
 
-  async updateAddresses(data: UpdateAddressDTO, sharedContext?: Context)
-  async updateAddresses(data: UpdateAddressDTO[], sharedContext?: Context)
+  async updateAddresses(
+    data: CartTypes.UpdateAddressDTO,
+    sharedContext?: Context
+  ): Promise<CartTypes.CartAddressDTO>
+  async updateAddresses(
+    data: CartTypes.UpdateAddressDTO[],
+    sharedContext?: Context
+  ): Promise<CartTypes.CartAddressDTO[]>
 
   @InjectManager("baseRepository_")
   async updateAddresses(
-    data: UpdateAddressDTO[] | UpdateAddressDTO,
+    data: CartTypes.UpdateAddressDTO[] | CartTypes.UpdateAddressDTO,
     @MedusaContext() sharedContext: Context = {}
-  ) {
+  ): Promise<CartTypes.CartAddressDTO | CartTypes.CartAddressDTO[]> {
     const input = Array.isArray(data) ? data : [data]
     const addresses = await this.updateAddresses_(input, sharedContext)
 
@@ -241,26 +504,26 @@ export default class CartModuleService implements ICartModuleService {
     )
 
     return (Array.isArray(data) ? result : result[0]) as
-      | AddressDTO
-      | AddressDTO[]
+      | CartTypes.CartAddressDTO
+      | CartTypes.CartAddressDTO[]
   }
 
   @InjectTransactionManager("baseRepository_")
   protected async updateAddresses_(
-    data: UpdateAddressDTO[],
+    data: CartTypes.UpdateAddressDTO[],
     @MedusaContext() sharedContext: Context = {}
   ) {
     return await this.addressService_.update(data, sharedContext)
   }
 
-  async deleteAddresses(ids: string[], sharedContext?: Context)
-  async deleteAddresses(ids: string, sharedContext?: Context)
+  async deleteAddresses(ids: string[], sharedContext?: Context): Promise<void>
+  async deleteAddresses(ids: string, sharedContext?: Context): Promise<void>
 
   @InjectTransactionManager("baseRepository_")
   async deleteAddresses(
     ids: string[] | string,
     @MedusaContext() sharedContext: Context = {}
-  ) {
+  ): Promise<void> {
     const addressIds = Array.isArray(ids) ? ids : [ids]
     await this.addressService_.delete(addressIds, sharedContext)
   }
diff --git a/packages/cart/src/services/index.ts b/packages/cart/src/services/index.ts
index 1f70a17a34..a72d00a336 100644
--- a/packages/cart/src/services/index.ts
+++ b/packages/cart/src/services/index.ts
@@ -1,4 +1,5 @@
 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"
 
diff --git a/packages/cart/src/services/line-item.ts b/packages/cart/src/services/line-item.ts
new file mode 100644
index 0000000000..445a631722
--- /dev/null
+++ b/packages/cart/src/services/line-item.ts
@@ -0,0 +1,128 @@
+import {
+  CartLineItemDTO,
+  Context,
+  DAL,
+  FilterableLineItemProps,
+  FindConfig,
+} from "@medusajs/types"
+import {
+  InjectManager,
+  InjectTransactionManager,
+  MedusaContext,
+  MedusaError,
+  ModulesSdkUtils,
+  retrieveEntity,
+} from "@medusajs/utils"
+import { LineItem } from "@models"
+import { LineItemRepository } from "@repositories"
+import { CreateLineItemDTO, UpdateLineItemDTO } from "../types"
+
+type InjectedDependencies = {
+  lineItemRepository: DAL.RepositoryService
+}
+
+export default class LineItemService<TEntity extends LineItem = LineItem> {
+  protected readonly lineItemRepository_: DAL.RepositoryService<LineItem>
+
+  constructor({ lineItemRepository }: InjectedDependencies) {
+    this.lineItemRepository_ = lineItemRepository
+  }
+
+  @InjectManager("lineItemRepository_")
+  async retrieve(
+    id: string,
+    config: FindConfig<CartLineItemDTO> = {},
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<TEntity> {
+    return (await retrieveEntity<LineItem, CartLineItemDTO>({
+      id: id,
+      entityName: LineItem.name,
+      repository: this.lineItemRepository_,
+      config,
+      sharedContext,
+    })) as TEntity
+  }
+
+  @InjectManager("lineItemRepository_")
+  async list(
+    filters: FilterableLineItemProps = {},
+    config: FindConfig<CartLineItemDTO> = {},
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<TEntity[]> {
+    const queryOptions = ModulesSdkUtils.buildQuery<LineItem>(filters, config)
+
+    return (await this.lineItemRepository_.find(
+      queryOptions,
+      sharedContext
+    )) as TEntity[]
+  }
+
+  @InjectManager("lineItemRepository_")
+  async listAndCount(
+    filters: FilterableLineItemProps = {},
+    config: FindConfig<CartLineItemDTO> = {},
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<[TEntity[], number]> {
+    const queryOptions = ModulesSdkUtils.buildQuery<LineItem>(filters, config)
+
+    return (await this.lineItemRepository_.findAndCount(
+      queryOptions,
+      sharedContext
+    )) as [TEntity[], number]
+  }
+
+  @InjectTransactionManager("lineItemRepository_")
+  async create(
+    data: CreateLineItemDTO[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<TEntity[]> {
+    return (await (this.lineItemRepository_ as LineItemRepository).create(
+      data,
+      sharedContext
+    )) as TEntity[]
+  }
+
+  @InjectTransactionManager("lineItemRepository_")
+  async update(
+    data: UpdateLineItemDTO[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<TEntity[]> {
+    const existingLines = await this.list(
+      { id: [...data.map((d) => d.id)] },
+      {},
+      sharedContext
+    )
+
+    const existingLinesMap = new Map(
+      existingLines.map<[string, LineItem]>((li) => [li.id, li])
+    )
+
+    const updates: UpdateLineItemDTO[] = []
+
+    for (const update of data) {
+      const lineItem = existingLinesMap.get(update.id)
+
+      if (!lineItem) {
+        throw new MedusaError(
+          MedusaError.Types.NOT_FOUND,
+          `Line item with id "${update.id}" not found`
+        )
+      }
+
+      updates.push({ ...update, id: lineItem.id })
+    }
+
+    return (await (this.lineItemRepository_ as LineItemRepository).update(
+      updates,
+      sharedContext
+    )) as TEntity[]
+  }
+
+  @InjectTransactionManager("lineItemRepository_")
+  async delete(
+    ids: string[],
+    @MedusaContext() sharedContext: Context = {}
+  ): Promise<void> {
+    await this.lineItemRepository_.delete(ids, sharedContext)
+  }
+}
diff --git a/packages/cart/src/types/index.ts b/packages/cart/src/types/index.ts
index 8b97276103..e9e853846c 100644
--- a/packages/cart/src/types/index.ts
+++ b/packages/cart/src/types/index.ts
@@ -1,6 +1,7 @@
 import { Logger } from "@medusajs/types"
 export * from "./address"
 export * from "./cart"
+export * from "./line-item"
 
 export type InitializeModuleInjectableDependencies = {
   logger?: Logger
diff --git a/packages/cart/src/types/line-item.ts b/packages/cart/src/types/line-item.ts
new file mode 100644
index 0000000000..b7fd239713
--- /dev/null
+++ b/packages/cart/src/types/line-item.ts
@@ -0,0 +1,37 @@
+interface PartialUpsertLineItemDTO {
+  subtitle?: string
+  thumbnail?: string
+
+  product_id?: string
+  product_title?: string
+  product_description?: string
+  product_subtitle?: string
+  product_type?: string
+  product_collection?: string
+  product_handle?: string
+
+  variant_id?: string
+  variant_sku?: string
+  variant_barcode?: string
+  variant_title?: string
+  variant_option_values?: Record<string, unknown>
+
+  requires_shipping?: boolean
+  is_discountable?: boolean
+  is_tax_inclusive?: boolean
+
+  compare_at_unit_price?: number
+}
+
+export interface CreateLineItemDTO extends PartialUpsertLineItemDTO {
+  title: string
+  quantity: number
+  unit_price: number
+  cart_id: string
+}
+
+export interface UpdateLineItemDTO
+  extends PartialUpsertLineItemDTO,
+    Partial<CreateLineItemDTO> {
+  id: string
+}
diff --git a/packages/core-flows/src/handlers/cart/create-cart.ts b/packages/core-flows/src/handlers/cart/create-cart.ts
index 198f5e33fb..bb926d211b 100644
--- a/packages/core-flows/src/handlers/cart/create-cart.ts
+++ b/packages/core-flows/src/handlers/cart/create-cart.ts
@@ -1,4 +1,4 @@
-import { AddressDTO, CustomerDTO, RegionDTO, legacy__CartDTO } from "@medusajs/types"
+import { AddressDTO, CustomerDTO, RegionDTO, legacy_CartDTO } from "@medusajs/types"
 import { WorkflowArguments } from "@medusajs/workflows-sdk"
 
 enum Aliases {
@@ -34,7 +34,7 @@ type HandlerInputData = {
 }
 
 type HandlerOutputData = {
-  cart: legacy__CartDTO
+  cart: legacy_CartDTO
 }
 
 export async function createCart({
diff --git a/packages/core-flows/src/handlers/cart/retrieve-cart.ts b/packages/core-flows/src/handlers/cart/retrieve-cart.ts
index 7f3f2884b8..8a5e3a2d01 100644
--- a/packages/core-flows/src/handlers/cart/retrieve-cart.ts
+++ b/packages/core-flows/src/handlers/cart/retrieve-cart.ts
@@ -1,4 +1,4 @@
-import { legacy__CartDTO } from "@medusajs/types"
+import { legacy_CartDTO } from "@medusajs/types"
 import { WorkflowArguments } from "@medusajs/workflows-sdk"
 
 type HandlerInputData = {
@@ -22,7 +22,7 @@ export async function retrieveCart({
   container,
   context,
   data,
-}: WorkflowArguments<HandlerInputData>): Promise<legacy__CartDTO> {
+}: WorkflowArguments<HandlerInputData>): Promise<legacy_CartDTO> {
   const { manager } = context
 
   const cartService = container.resolve("cartService")
diff --git a/packages/types/src/cart/common.ts b/packages/types/src/cart/common.ts
index 1e17abf889..6c345d5945 100644
--- a/packages/types/src/cart/common.ts
+++ b/packages/types/src/cart/common.ts
@@ -336,6 +336,16 @@ export interface CartLineItemDTO {
    * @expandable
    */
   adjustments?: LineItemAdjustmentLineDTO[]
+  /**
+   * The associated cart.
+   *
+   * @expandable
+   */
+  cart: CartDTO
+  /**
+   * The ID of the associated cart.
+   */
+  cart_id: string
   /**
    * Holds custom data in key-value pairs.
    */
@@ -470,12 +480,20 @@ export interface FilterableAddressProps
   id?: string | string[]
 }
 
+export interface FilterableLineItemProps
+  extends BaseFilterable<FilterableLineItemProps> {
+  id?: string | string[]
+  cart_id?: string | string[]
+  title?: string
+  variant_id?: string | string[]
+  product_id?: string | string[]
+}
+
 /**
  * TODO: Remove this in favor of CartDTO, when module is released 
  * @deprecated Use CartDTO instead
  */
- 
-export type legacy__CartDTO = {
+export type legacy_CartDTO = {
   id?: string
   email?: string
   billing_address_id?: string
diff --git a/packages/types/src/cart/mutations.ts b/packages/types/src/cart/mutations.ts
index 0ed7f581aa..f128d819c9 100644
--- a/packages/types/src/cart/mutations.ts
+++ b/packages/types/src/cart/mutations.ts
@@ -1,3 +1,5 @@
+import { CartLineItemDTO } from "./common"
+
 export interface UpsertAddressDTO {
   customer_id?: string
   company?: string
@@ -93,6 +95,8 @@ export interface CreateLineItemDTO {
   subtitle?: string
   thumbnail?: string
 
+  cart_id?: string
+
   quantity: number
 
   product_id?: string
@@ -116,24 +120,30 @@ export interface CreateLineItemDTO {
   compare_at_unit_price?: number
   unit_price: number
 
-  tax_lines: CreateLineItemTaxLineDTO[]
-  adjustments: CreateLineItemAdjustmentDTO[]
+  tax_lines?: CreateLineItemTaxLineDTO[]
+  adjustments?: CreateLineItemAdjustmentDTO[]
+}
+
+export interface CreateLineItemForCartDTO extends CreateLineItemDTO {
+  cart_id: string
+}
+
+export interface UpdateLineItemWithSelectorDTO {
+  selector: Partial<CartLineItemDTO>
+  data: Partial<UpdateLineItemDTO>
 }
 
 export interface UpdateLineItemDTO
-  extends Omit<CreateLineItemDTO, "tax_lines" | "adjustments"> {
+  extends Omit<
+    CreateLineItemDTO,
+    "tax_lines" | "adjustments" | "title" | "quantity" | "unit_price"
+  > {
   id: string
 
-  tax_lines: UpdateLineItemTaxLineDTO[] | CreateLineItemTaxLineDTO[]
-  adjustments: UpdateLineItemAdjustmentDTO[] | CreateLineItemAdjustmentDTO[]
-}
+  title?: string
+  quantity?: number
+  unit_price?: number
 
-export interface AddLineItemsDTO {
-  cart_id: string
-  items: CreateLineItemDTO[]
-}
-
-export interface UpdateLineItemsDTO {
-  cart_id: string
-  items: UpdateLineItemDTO[]
+  tax_lines?: UpdateLineItemTaxLineDTO[] | CreateLineItemTaxLineDTO[]
+  adjustments?: UpdateLineItemAdjustmentDTO[] | CreateLineItemAdjustmentDTO[]
 }
diff --git a/packages/types/src/cart/service.ts b/packages/types/src/cart/service.ts
index caba8cfb1d..9f7f413acc 100644
--- a/packages/types/src/cart/service.ts
+++ b/packages/types/src/cart/service.ts
@@ -1,13 +1,22 @@
-import { AddressDTO } from "../address"
 import { FindConfig } from "../common"
 import { IModuleService } from "../modules-sdk"
 import { Context } from "../shared-context"
-import { CartAddressDTO, CartDTO, FilterableAddressProps, FilterableCartProps } from "./common"
+import {
+  CartAddressDTO,
+  CartDTO,
+  CartLineItemDTO,
+  FilterableAddressProps,
+  FilterableCartProps,
+} from "./common"
 import {
   CreateAddressDTO,
   CreateCartDTO,
+  CreateLineItemDTO,
+  CreateLineItemForCartDTO,
   UpdateAddressDTO,
   UpdateCartDTO,
+  UpdateLineItemDTO,
+  UpdateLineItemWithSelectorDTO,
 } from "./mutations"
 
 export interface ICartModuleService extends IModuleService {
@@ -40,7 +49,7 @@ export interface ICartModuleService extends IModuleService {
 
   listAddresses(
     filters?: FilterableAddressProps,
-    config?: FindConfig<AddressDTO>,
+    config?: FindConfig<CartAddressDTO>,
     sharedContext?: Context
   ): Promise<CartAddressDTO[]>
 
@@ -65,20 +74,32 @@ export interface ICartModuleService extends IModuleService {
   deleteAddresses(ids: string[], sharedContext?: Context): Promise<void>
   deleteAddresses(ids: string, sharedContext?: Context): Promise<void>
 
-  // addLineItems(data: AddLineItemsDTO, sharedContext?: Context): Promise<CartDTO>
-  // addLineItems(
-  //   data: AddLineItemsDTO[],
-  //   sharedContext?: Context
-  // ): Promise<CartDTO[]>
+  addLineItems(data: CreateLineItemForCartDTO): Promise<CartLineItemDTO>
+  addLineItems(data: CreateLineItemForCartDTO[]): Promise<CartLineItemDTO[]>
+  addLineItems(
+    cartId: string,
+    items: CreateLineItemDTO[],
+    sharedContext?: Context
+  ): Promise<CartLineItemDTO[]>
 
-  // updateLineItems(
-  //   data: UpdateLineItemsDTO,
-  //   sharedContext?: Context
-  // ): Promise<CartDTO>
-  // updateLineItems(
-  //   data: UpdateLineItemsDTO[],
-  //   sharedContext?: Context
-  // ): Promise<CartDTO[]>
+  updateLineItems(
+    data: UpdateLineItemWithSelectorDTO[]
+  ): Promise<CartLineItemDTO[]>
+  updateLineItems(
+    selector: Partial<CartLineItemDTO>,
+    data: Partial<UpdateLineItemDTO>,
+    sharedContext?: Context
+  ): Promise<CartLineItemDTO[]>
+  updateLineItems(
+    lineId: string,
+    data: Partial<UpdateLineItemDTO>,
+    sharedContext?: Context
+  ): Promise<CartLineItemDTO>
 
-  // removeLineItems(lineItemIds: string[], sharedContext?: Context): Promise<void>
+  removeLineItems(itemIds: string[], sharedContext?: Context): Promise<void>
+  removeLineItems(itemIds: string, sharedContext?: Context): Promise<void>
+  removeLineItems(
+    selector: Partial<CartLineItemDTO>,
+    sharedContext?: Context
+  ): Promise<void>
 }