Stripe payment provider plugin (#65)

Adds Stripe payment provider plugin

Closes #44

packages/medusa-payment-stripe/.babelrc

@@ -1,7 +1,8 @@
 {
   "plugins": [
     "@babel/plugin-proposal-class-properties",
-    "@babel/plugin-transform-instanceof"
+    "@babel/plugin-transform-instanceof",
+    "@babel/plugin-transform-classes"
   ],
   "presets": ["@babel/preset-env"],
   "env": {

packages/medusa-payment-stripe/.gitignore

@@ -6,8 +6,5 @@ node_modules
 !index.js
 yarn.lock
 
-/api
-/services
-/models
-/subscribers
+/dist
 

packages/medusa-payment-stripe/package.json

@@ -13,11 +13,12 @@
   "devDependencies": {
     "@babel/cli": "^7.7.5",
     "@babel/core": "^7.7.5",
+    "@babel/node": "^7.7.4",
     "@babel/plugin-proposal-class-properties": "^7.7.4",
-    "@babel/plugin-transform-runtime": "^7.7.6",
-    "@babel/plugin-transform-classes": "^7.9.5",
     "@babel/plugin-transform-instanceof": "^7.8.3",
+    "@babel/plugin-transform-runtime": "^7.7.6",
     "@babel/preset-env": "^7.7.5",
+    "@babel/register": "^7.7.4",
     "@babel/runtime": "^7.9.6",
     "client-sessions": "^0.8.0",
     "cross-env": "^5.2.1",
@@ -25,14 +26,19 @@
     "jest": "^25.5.2"
   },
   "scripts": {
-    "build": "babel src --out-dir . --ignore **/__tests__",
+    "build": "babel src -d dist",
     "prepare": "cross-env NODE_ENV=production npm run build",
-    "watch": "babel -w src --out-dir . --ignore **/__tests__"
+    "watch": "babel -w src --out-dir . --ignore **/__tests__",
+    "test": "jest"
   },
   "dependencies": {
+    "@babel/plugin-transform-classes": "^7.9.5",
     "express": "^4.17.1",
     "medusa-core-utils": "^0.3.0",
-    "medusa-interfaces": "^0.3.0"
+    "medusa-interfaces": "^0.3.0",
+    "medusa-test-utils": "^0.3.0",
+    "stripe": "^8.50.0",
+    "body-parser": "^1.19.0"
   },
   "gitHead": "35e0930650d5f4aedf2610749cd131ae8b7e17cc"
-}
+}

packages/medusa-payment-stripe/src/__mocks__/cart.js

@@ -0,0 +1,212 @@
+import { IdMap } from "medusa-test-utils"
+
+export const carts = {
+  emptyCart: {
+    _id: IdMap.getId("emptyCart"),
+    items: [],
+    region_id: IdMap.getId("testRegion"),
+    shipping_options: [
+      {
+        _id: IdMap.getId("freeShipping"),
+        profile_id: "default_profile",
+        data: {
+          some_data: "yes",
+        },
+      },
+    ],
+  },
+  frCart: {
+    _id: IdMap.getId("fr-cart"),
+    email: "lebron@james.com",
+    title: "test",
+    region_id: IdMap.getId("region-france"),
+    items: [
+      {
+        _id: IdMap.getId("line"),
+        title: "merge line",
+        description: "This is a new line",
+        thumbnail: "test-img-yeah.com/thumb",
+        content: [
+          {
+            unit_price: 8,
+            variant: {
+              _id: IdMap.getId("eur-8-us-10"),
+            },
+            product: {
+              _id: IdMap.getId("product"),
+            },
+            quantity: 1,
+          },
+          {
+            unit_price: 10,
+            variant: {
+              _id: IdMap.getId("eur-10-us-12"),
+            },
+            product: {
+              _id: IdMap.getId("product"),
+            },
+            quantity: 1,
+          },
+        ],
+        quantity: 10,
+      },
+      {
+        _id: IdMap.getId("existingLine"),
+        title: "merge line",
+        description: "This is a new line",
+        thumbnail: "test-img-yeah.com/thumb",
+        content: {
+          unit_price: 10,
+          variant: {
+            _id: IdMap.getId("eur-10-us-12"),
+          },
+          product: {
+            _id: IdMap.getId("product"),
+          },
+          quantity: 1,
+        },
+        quantity: 10,
+      },
+    ],
+    shipping_methods: [
+      {
+        _id: IdMap.getId("freeShipping"),
+        profile_id: "default_profile",
+      },
+    ],
+    shipping_options: [
+      {
+        _id: IdMap.getId("freeShipping"),
+        profile_id: "default_profile",
+      },
+    ],
+    payment_sessions: [
+      {
+        provider_id: "stripe",
+        data: {
+          id: "pi_123456789",
+          customer: IdMap.getId("not-lebron"),
+        },
+      },
+    ],
+    payment_method: {
+      provider_id: "stripe",
+      data: {
+        id: "pi_123456789",
+        customer: IdMap.getId("not-lebron"),
+      },
+    },
+    shipping_address: {},
+    billing_address: {},
+    discounts: [],
+    customer_id: IdMap.getId("lebron"),
+  },
+  frCartNoStripeCustomer: {
+    _id: IdMap.getId("fr-cart-no-customer"),
+    title: "test",
+    region_id: IdMap.getId("region-france"),
+    items: [
+      {
+        _id: IdMap.getId("line"),
+        title: "merge line",
+        description: "This is a new line",
+        thumbnail: "test-img-yeah.com/thumb",
+        content: [
+          {
+            unit_price: 8,
+            variant: {
+              _id: IdMap.getId("eur-8-us-10"),
+            },
+            product: {
+              _id: IdMap.getId("product"),
+            },
+            quantity: 1,
+          },
+          {
+            unit_price: 10,
+            variant: {
+              _id: IdMap.getId("eur-10-us-12"),
+            },
+            product: {
+              _id: IdMap.getId("product"),
+            },
+            quantity: 1,
+          },
+        ],
+        quantity: 10,
+      },
+      {
+        _id: IdMap.getId("existingLine"),
+        title: "merge line",
+        description: "This is a new line",
+        thumbnail: "test-img-yeah.com/thumb",
+        content: {
+          unit_price: 10,
+          variant: {
+            _id: IdMap.getId("eur-10-us-12"),
+          },
+          product: {
+            _id: IdMap.getId("product"),
+          },
+          quantity: 1,
+        },
+        quantity: 10,
+      },
+    ],
+    shipping_methods: [
+      {
+        _id: IdMap.getId("freeShipping"),
+        profile_id: "default_profile",
+      },
+    ],
+    shipping_options: [
+      {
+        _id: IdMap.getId("freeShipping"),
+        profile_id: "default_profile",
+      },
+    ],
+    payment_sessions: [
+      {
+        provider_id: "stripe",
+        data: {
+          id: "pi_123456789",
+          customer: IdMap.getId("not-lebron"),
+        },
+      },
+    ],
+    payment_method: {
+      provider_id: "stripe",
+      data: {
+        id: "pi_123456789",
+        customer: IdMap.getId("not-lebron"),
+      },
+    },
+    shipping_address: {},
+    billing_address: {},
+    discounts: [],
+    customer_id: IdMap.getId("vvd"),
+  },
+}
+
+export const CartServiceMock = {
+  retrieve: jest.fn().mockImplementation((cartId) => {
+    if (cartId === IdMap.getId("fr-cart")) {
+      return Promise.resolve(carts.frCart)
+    }
+    if (cartId === IdMap.getId("emptyCart")) {
+      return Promise.resolve(carts.emptyCart)
+    }
+    return Promise.resolve(undefined)
+  }),
+  updatePaymentSession: jest
+    .fn()
+    .mockImplementation((cartId, stripe, paymentIntent) => {
+      return Promise.resolve()
+    }),
+}
+
+const mock = jest.fn().mockImplementation(() => {
+  return CartServiceMock
+})
+
+export default mock

packages/medusa-payment-stripe/src/__mocks__/customer.js

@@ -0,0 +1,36 @@
+import { IdMap } from "medusa-test-utils"
+
+export const CustomerServiceMock = {
+  retrieve: jest.fn().mockImplementation((id) => {
+    if (id === IdMap.getId("lebron")) {
+      return Promise.resolve({
+        _id: IdMap.getId("lebron"),
+        first_name: "LeBron",
+        last_name: "James",
+        email: "lebron@james.com",
+        password_hash: "1234",
+        metadata: {
+          stripe_id: "cus_123456789_new",
+        },
+      })
+    }
+    if (id === IdMap.getId("vvd")) {
+      return Promise.resolve({
+        _id: IdMap.getId("vvd"),
+        first_name: "Virgil",
+        last_name: "Van Dijk",
+        email: "virg@vvd.com",
+        password_hash: "1234",
+        metadata: {},
+      })
+    }
+    return Promise.resolve(undefined)
+  }),
+  setMetadata: jest.fn().mockReturnValue(Promise.resolve()),
+}
+
+const mock = jest.fn().mockImplementation(() => {
+  return CustomerServiceMock
+})
+
+export default mock

packages/medusa-payment-stripe/src/__mocks__/eventbus.js

@@ -0,0 +1,10 @@
+export const EventBusServiceMock = {
+  emit: jest.fn(),
+  subscribe: jest.fn(),
+}
+
+const mock = jest.fn().mockImplementation(() => {
+  return EventBusServiceMock
+})
+
+export default mock

packages/medusa-payment-stripe/src/__mocks__/stripe.js

@@ -0,0 +1,85 @@
+export const StripeMock = {
+  customers: {
+    create: jest.fn().mockImplementation((data) => {
+      if (data.email === "virg@vvd.com") {
+        return Promise.resolve({
+          id: "cus_vvd",
+          email: "virg@vvd.com",
+        })
+      }
+      if (data.email === "lebron@james.com") {
+        return Promise.resolve({
+          id: "cus_lebron",
+          email: "lebron@james.com",
+        })
+      }
+    }),
+  },
+  paymentIntents: {
+    create: jest.fn().mockImplementation((data) => {
+      if (data.customer === "cus_123456789_new") {
+        return Promise.resolve({
+          id: "pi_lebron",
+          amount: 100,
+          customer: "cus_123456789_new",
+        })
+      }
+      if (data.customer === "cus_lebron") {
+        return Promise.resolve({
+          id: "pi_lebron",
+          amount: 100,
+          customer: "cus_lebron",
+        })
+      }
+    }),
+    retrieve: jest.fn().mockImplementation((data) => {
+      return Promise.resolve({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+      })
+    }),
+    update: jest.fn().mockImplementation((pi, data) => {
+      if (data.customer === "cus_lebron_2") {
+        return Promise.resolve({
+          id: "pi_lebron",
+          customer: "cus_lebron_2",
+          amount: 1000,
+        })
+      }
+      return Promise.resolve({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+        amount: 1000,
+      })
+    }),
+    capture: jest.fn().mockImplementation((data) => {
+      return Promise.resolve({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+        amount: 1000,
+        status: "succeeded",
+      })
+    }),
+    cancel: jest.fn().mockImplementation((data) => {
+      return Promise.resolve({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+        status: "cancelled",
+      })
+    }),
+  },
+  refunds: {
+    create: jest.fn().mockImplementation((data) => {
+      return Promise.resolve({
+        id: "re_123",
+        payment_intent: "pi_lebron",
+        amount: 1000,
+        status: "succeeded",
+      })
+    }),
+  },
+}
+
+const stripe = jest.fn(() => StripeMock)
+
+export default stripe

packages/medusa-payment-stripe/src/__mocks__/totals.js

@@ -0,0 +1,9 @@
+export const TotalsServiceMock = {
+  getTotal: jest.fn(),
+}
+
+const mock = jest.fn().mockImplementation(() => {
+  return TotalsServiceMock
+})
+
+export default mock

packages/medusa-payment-stripe/src/api/index.js

@@ -1,14 +1,10 @@
 import { Router } from "express"
+import hooks from "./routes/hooks"
 
-export default () => {
+export default (container) => {
   const app = Router()
 
-  app.get("/stripe", (req, res) => {
-    console.log("hi")
-    res.json({
-      success: true
-    })
-  })
+  hooks(app)
 
   return app
 }

packages/medusa-payment-stripe/src/api/middlewares/await-middleware.js

@@ -0,0 +1 @@
+export default (fn) => (...args) => fn(...args).catch(args[2])

packages/medusa-payment-stripe/src/api/middlewares/index.js

@@ -0,0 +1,5 @@
+import { default as wrap } from "./await-middleware"
+
+export default {
+  wrap,
+}

packages/medusa-payment-stripe/src/api/routes/hooks/index.js

@@ -0,0 +1,17 @@
+import { Router } from "express"
+import bodyParser from "body-parser"
+import middlewares from "../../middlewares"
+
+const route = Router()
+
+export default (app) => {
+  app.use("/hooks", route)
+
+  route.post(
+    "/stripe",
+    // stripe constructEvent fails without body-parser
+    bodyParser.raw({ type: "application/json" }),
+    middlewares.wrap(require("./stripe").default)
+  )
+  return app
+}

packages/medusa-payment-stripe/src/api/routes/hooks/stripe.js

@@ -0,0 +1,35 @@
+export default async (req, res) => {
+  const signature = req.headers["stripe-signature"]
+
+  let event
+  try {
+    const stripeProviderService = req.resolve("pp_stripe")
+    event = stripeProviderService.constructWebhookEvent(req.body, signature)
+  } catch (err) {
+    res.status(400).send(`Webhook Error: ${err.message}`)
+    return
+  }
+
+  const paymentIntent = event.data.object
+
+  // handle payment intent events
+  switch (event.type) {
+    case "payment_intent.succeeded":
+      break
+    case "payment_intent.canceled":
+      break
+    case "payment_intent.created":
+      break
+    case "payment_intent.payment_failed":
+      break
+    case "payment_intent.amount_capturable_updated":
+      break
+    case "payment_intent.processing":
+      break
+    default:
+      res.status(400)
+      return
+  }
+
+  res.sendStatus(200)
+}

packages/medusa-payment-stripe/src/services/__mocks__/stripe-provider.js

@@ -0,0 +1,52 @@
+import { IdMap } from "medusa-test-utils"
+
+export const StripeProviderServiceMock = {
+  retrievePayment: jest.fn().mockImplementation((cart) => {
+    if (cart._id === IdMap.getId("fr-cart")) {
+      return Promise.resolve({
+        id: "pi",
+        customer: "cus_123456789",
+      })
+    }
+    if (cart._id === IdMap.getId("fr-cart-no-customer")) {
+      return Promise.resolve({
+        id: "pi",
+      })
+    }
+    return Promise.resolve(undefined)
+  }),
+  cancelPayment: jest.fn().mockImplementation((cart) => {
+    return Promise.resolve()
+  }),
+  updatePaymentIntentCustomer: jest.fn().mockImplementation((cart) => {
+    return Promise.resolve()
+  }),
+  retrieveCustomer: jest.fn().mockImplementation((customerId) => {
+    if (customerId === "cus_123456789_new") {
+      return Promise.resolve({
+        id: "cus_123456789_new",
+      })
+    }
+    return Promise.resolve(undefined)
+  }),
+  createCustomer: jest.fn().mockImplementation((customer) => {
+    if (customer._id === IdMap.getId("vvd")) {
+      return Promise.resolve({
+        id: "cus_123456789_new_vvd",
+      })
+    }
+    return Promise.resolve(undefined)
+  }),
+  createPayment: jest.fn().mockImplementation((cart) => {
+    return Promise.resolve({
+      id: "pi_new",
+      customer: "cus_123456789_new",
+    })
+  }),
+}
+
+const mock = jest.fn().mockImplementation(() => {
+  return StripeProviderServiceMock
+})
+
+export default mock

packages/medusa-payment-stripe/src/services/__tests__/stripe-provider.js

@@ -0,0 +1,243 @@
+import { IdMap } from "medusa-test-utils"
+import StripeProviderService from "../stripe-provider"
+import { CustomerServiceMock } from "../../__mocks__/customer"
+import { carts } from "../../__mocks__/cart"
+import { TotalsServiceMock } from "../../__mocks__/totals"
+
+describe("StripeProviderService", () => {
+  describe("createCustomer", () => {
+    let result
+    beforeAll(async () => {
+      jest.clearAllMocks()
+      const stripeProviderService = new StripeProviderService(
+        {
+          customerService: CustomerServiceMock,
+          totalsService: TotalsServiceMock,
+        },
+        {
+          api_key: "test",
+        }
+      )
+
+      result = await stripeProviderService.createCustomer({
+        _id: IdMap.getId("vvd"),
+        first_name: "Virgil",
+        last_name: "Van Dijk",
+        email: "virg@vvd.com",
+        password_hash: "1234",
+        metadata: {},
+      })
+    })
+
+    it("returns created stripe customer", () => {
+      expect(result).toEqual({
+        id: "cus_vvd",
+        email: "virg@vvd.com",
+      })
+    })
+  })
+
+  describe("createPayment", () => {
+    let result
+    const stripeProviderService = new StripeProviderService(
+      {
+        customerService: CustomerServiceMock,
+        totalsService: TotalsServiceMock,
+      },
+      {
+        api_key: "test",
+      }
+    )
+
+    beforeEach(async () => {
+      jest.clearAllMocks()
+    })
+
+    it("returns created stripe payment intent for cart with existing customer", async () => {
+      result = await stripeProviderService.createPayment(carts.frCart)
+      expect(result).toEqual({
+        id: "pi_lebron",
+        customer: "cus_123456789_new",
+        amount: 100,
+      })
+    })
+
+    it("returns created stripe payment intent for cart with no customer", async () => {
+      carts.frCart.customer_id = ""
+      result = await stripeProviderService.createPayment(carts.frCart)
+      expect(result).toEqual({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+        amount: 100,
+      })
+    })
+  })
+
+  describe("retrievePayment", () => {
+    let result
+    beforeAll(async () => {
+      jest.clearAllMocks()
+      const stripeProviderService = new StripeProviderService(
+        {
+          customerService: CustomerServiceMock,
+          totalsService: TotalsServiceMock,
+        },
+        {
+          api_key: "test",
+        }
+      )
+
+      result = await stripeProviderService.retrievePayment({
+        payment_method: {
+          data: {
+            id: "pi_lebron",
+          },
+        },
+      })
+    })
+
+    it("returns stripe payment intent", () => {
+      expect(result).toEqual({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+      })
+    })
+  })
+
+  describe("updatePayment", () => {
+    let result
+    beforeAll(async () => {
+      jest.clearAllMocks()
+      const stripeProviderService = new StripeProviderService(
+        {
+          customerService: CustomerServiceMock,
+          totalsService: TotalsServiceMock,
+        },
+        {
+          api_key: "test",
+        }
+      )
+
+      result = await stripeProviderService.updatePayment(
+        {
+          payment_method: {
+            data: {
+              id: "pi_lebron",
+            },
+          },
+        },
+        {
+          amount: 1000,
+        }
+      )
+    })
+
+    it("returns cancelled stripe payment intent", () => {
+      expect(result).toEqual({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+        amount: 1000,
+      })
+    })
+  })
+
+  describe("updatePaymentIntentCustomer", () => {
+    let result
+    beforeAll(async () => {
+      jest.clearAllMocks()
+      const stripeProviderService = new StripeProviderService(
+        {
+          customerService: CustomerServiceMock,
+          totalsService: TotalsServiceMock,
+        },
+        {
+          api_key: "test",
+        }
+      )
+
+      result = await stripeProviderService.updatePaymentIntentCustomer(
+        "pi_lebron",
+        "cus_lebron_2"
+      )
+    })
+
+    it("returns update stripe payment intent", () => {
+      expect(result).toEqual({
+        id: "pi_lebron",
+        customer: "cus_lebron_2",
+        amount: 1000,
+      })
+    })
+  })
+
+  describe("capturePayment", () => {
+    let result
+    beforeAll(async () => {
+      jest.clearAllMocks()
+      const stripeProviderService = new StripeProviderService(
+        {},
+        {
+          api_key: "test",
+        }
+      )
+
+      result = await stripeProviderService.capturePayment("pi_lebron")
+    })
+
+    it("returns captured stripe payment intent", () => {
+      expect(result).toEqual({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+        amount: 1000,
+        status: "succeeded",
+      })
+    })
+  })
+
+  describe("refundPayment", () => {
+    let result
+    beforeAll(async () => {
+      jest.clearAllMocks()
+      const stripeProviderService = new StripeProviderService(
+        {},
+        {
+          api_key: "test",
+        }
+      )
+
+      result = await stripeProviderService.refundPayment("pi_lebron", 1000)
+    })
+
+    it("returns refunded stripe payment intent", () => {
+      expect(result).toEqual({
+        id: "re_123",
+        payment_intent: "pi_lebron",
+        amount: 1000,
+        status: "succeeded",
+      })
+    })
+  })
+
+  describe("cancelPayment", () => {
+    let result
+    beforeAll(async () => {
+      jest.clearAllMocks()
+      const stripeProviderService = new StripeProviderService(
+        {},
+        {
+          api_key: "test",
+        }
+      )
+
+      result = await stripeProviderService.cancelPayment("pi_lebron")
+    })
+
+    it("returns cancelled stripe payment intent", () => {
+      expect(result).toEqual({
+        id: "pi_lebron",
+        customer: "cus_lebron",
+        status: "cancelled",
+      })
+    })
+  })
+})

packages/medusa-payment-stripe/src/services/stripe-provider.js

@@ -1,12 +1,214 @@
 import _ from "lodash"
+import Stripe from "stripe"
 import { PaymentService } from "medusa-interfaces"
 
 class StripeProviderService extends PaymentService {
   static identifier = "stripe"
 
-  constructor(appScope, options) {
+  constructor({ customerService, totalsService }, options) {
     super()
-    console.log(options)
+
+    this.options_ = options
+
+    this.stripe_ = Stripe(options.api_key)
+
+    this.customerService_ = customerService
+
+    this.totalsService_ = totalsService
+  }
+
+  /**
+   * Status for Stripe PaymentIntent.
+   * @param {Object} paymentData - payment method data from cart
+   * @returns {string} the status of the payment intent
+   */
+  async getStatus(paymentData) {
+    const { id } = paymentData
+
+    const paymentIntent = await this.stripe_.paymentIntents.retrieve(id)
+
+    let status = "initial"
+
+    if (paymentIntent.status === "requires_payment_method") {
+      return status
+    }
+
+    if (paymentIntent.status === "requires_action") {
+      status = "authorized"
+    }
+
+    if (paymentIntent.status === "succeeded") {
+      status = "succeeded"
+    }
+
+    if (paymentIntent.status === "cancelled") {
+      status = "cancelled"
+    }
+
+    return status
+  }
+
+  async retrieveCustomer(customerId) {
+    return this.stripe_.customers.retrieve(customerId)
+  }
+
+  // customer metadata
+  async createCustomer(customer) {
+    try {
+      const stripeCustomer = await this.stripe_.customers.create({
+        email: customer.email,
+      })
+      await this.customerService_.setMetadata(
+        customer._id,
+        "stripe_id",
+        stripeCustomer.id
+      )
+      return stripeCustomer
+    } catch (error) {
+      throw error
+    }
+  }
+
+  /**
+   * Creates Stripe PaymentIntent.
+   * @param {string} cart - the cart to create a payment for
+   * @param {number} amount - the amount to create a payment for
+   * @returns {string} id of payment intent
+   */
+  async createPayment(cart) {
+    const { customer_id } = cart
+
+    let stripeCustomerId
+
+    if (!customer_id) {
+      const { id } = await this.stripe_.customers.create({
+        email: cart.email,
+      })
+      stripeCustomerId = id
+    } else {
+      const customer = await this.customerService_.retrieve(customer_id)
+      if (!customer.metadata.stripe_id) {
+        const { id } = await this.stripe_.customers.create({
+          email: customer.email,
+        })
+        await this.customerService_.setMetadata(customer._id, "stripe_id", id)
+      } else {
+        stripeCustomerId = customer.metadata.stripe_id
+      }
+    }
+
+    const amount = this.totalsService_.getTotal(cart)
+    const paymentIntent = await this.stripe_.paymentIntents.create({
+      customer: stripeCustomerId,
+      amount,
+    })
+
+    return paymentIntent
+  }
+
+  /**
+   * Retrieves Stripe PaymentIntent.
+   * @param {string} cart - the cart to retrieve payment intent for
+   * @returns {Object} Stripe PaymentIntent
+   */
+  async retrievePayment(cart) {
+    try {
+      const { data } = cart.payment_method
+      return this.stripe_.paymentIntents.retrieve(data.id)
+    } catch (error) {
+      throw error
+    }
+  }
+
+  /**
+   * Updates Stripe PaymentIntent.
+   * @param {string} cart - the cart to update payment intent for
+   * @param {Object} data - the update object for the payment intent
+   * @returns {Object} Stripe PaymentIntent
+   */
+  async updatePayment(cart, update) {
+    try {
+      const { data } = cart.payment_method
+      return this.stripe_.paymentIntents.update(data.id, update)
+    } catch (error) {
+      throw error
+    }
+  }
+
+  /**
+   * Updates customer of Stripe PaymentIntent.
+   * @param {string} cart - the cart to update payment intent for
+   * @param {Object} data - the update object for the payment intent
+   * @returns {Object} Stripe PaymentIntent
+   */
+  async updatePaymentIntentCustomer(paymentIntent, id) {
+    try {
+      return this.stripe_.paymentIntents.update(paymentIntent, {
+        customer: id,
+      })
+    } catch (error) {
+      throw error
+    }
+  }
+
+  /**
+   * Captures payment for Stripe PaymentIntent.
+   * @param {Object} paymentData - payment method data from cart
+   * @returns {Object} Stripe PaymentIntent
+   */
+  async capturePayment(paymentData) {
+    const { id } = paymentData
+    try {
+      return this.stripe_.paymentIntents.capture(id)
+    } catch (error) {
+      throw error
+    }
+  }
+
+  /**
+   * Refunds payment for Stripe PaymentIntent.
+   * @param {Object} paymentData - payment method data from cart
+   * @returns {string} id of payment intent
+   */
+  async refundPayment(paymentData, amount) {
+    const { id } = paymentData
+    try {
+      return this.stripe_.refunds.create({
+        amount,
+        payment_intent: id,
+      })
+    } catch (error) {
+      throw error
+    }
+  }
+
+  /**
+   * Cancels payment for Stripe PaymentIntent.
+   * @param {Object} paymentData - payment method data from cart
+   * @returns {string} id of payment intent
+   */
+  async cancelPayment(paymentData) {
+    const { id } = paymentData
+    try {
+      return this.stripe_.paymentIntents.cancel(id)
+    } catch (error) {
+      throw error
+    }
+  }
+
+  /**
+   * Constructs Stripe Webhook event
+   * @param {Object} data - the data of the webhook request: req.body
+   * @param {Object} signature - the Stripe signature on the event, that
+   *    ensures integrity of the webhook event
+   * @returns {Object} Stripe Webhook event
+   */
+  constructWebhookEvent(data, signature) {
+    return this.stripe_.webhooks.constructEvent(
+      data,
+      signature,
+      this.options_.webhook_secret
+    )
   }
 }
 

packages/medusa-payment-stripe/src/subscribers/__tests__/cart.js

@@ -0,0 +1,90 @@
+import { IdMap } from "medusa-test-utils"
+import { carts, CartServiceMock } from "../../__mocks__/cart"
+import { CustomerServiceMock } from "../../__mocks__/customer"
+import { StripeProviderServiceMock } from "../../services/__mocks__/stripe-provider"
+import { EventBusServiceMock } from "../../__mocks__/eventbus"
+import CartSubscriber from "../cart"
+
+describe("CartSubscriber", () => {
+  describe("onCustomerUpdated", () => {
+    let cartSubcriber = new CartSubscriber({
+      eventBusService: EventBusServiceMock,
+      cartService: CartServiceMock,
+      stripeProviderService: StripeProviderServiceMock,
+      customerService: CustomerServiceMock,
+    })
+
+    beforeEach(async () => {
+      jest.clearAllMocks()
+    })
+
+    it("resolves on non-existing payment data", async () => {
+      await cartSubcriber.onCustomerUpdated(carts.emptyCart)
+
+      expect(CustomerServiceMock.retrieve).toHaveBeenCalledTimes(0)
+    })
+
+    it("cancels old and creates new payment intent with the updated existing customer", async () => {
+      await cartSubcriber.onCustomerUpdated(carts.frCart)
+
+      expect(CustomerServiceMock.retrieve).toHaveBeenCalledTimes(1)
+      expect(CustomerServiceMock.retrieve).toHaveBeenCalledWith(
+        IdMap.getId("lebron")
+      )
+
+      expect(StripeProviderServiceMock.retrievePayment).toHaveBeenCalledTimes(1)
+      expect(StripeProviderServiceMock.retrievePayment).toHaveBeenCalledWith(
+        carts.frCart
+      )
+
+      expect(StripeProviderServiceMock.cancelPayment).toHaveBeenCalledTimes(1)
+      expect(StripeProviderServiceMock.cancelPayment).toHaveBeenCalledWith("pi")
+
+      expect(StripeProviderServiceMock.createPayment).toHaveBeenCalledTimes(1)
+      expect(StripeProviderServiceMock.createPayment).toHaveBeenCalledWith(
+        carts.frCart
+      )
+
+      expect(CartServiceMock.updatePaymentSession).toHaveBeenCalledTimes(1)
+      expect(CartServiceMock.updatePaymentSession).toHaveBeenCalledWith(
+        IdMap.getId("fr-cart"),
+        "stripe",
+        {
+          id: "pi_new",
+          customer: "cus_123456789_new",
+        }
+      )
+    })
+
+    it("cancels old and creates new payment intent and creates new stripe customer", async () => {
+      await cartSubcriber.onCustomerUpdated(carts.frCartNoStripeCustomer)
+
+      expect(CustomerServiceMock.retrieve).toHaveBeenCalledTimes(1)
+      expect(CustomerServiceMock.retrieve).toHaveBeenCalledWith(
+        IdMap.getId("vvd")
+      )
+
+      expect(StripeProviderServiceMock.retrievePayment).toHaveBeenCalledTimes(1)
+      expect(StripeProviderServiceMock.retrievePayment).toHaveBeenCalledWith(
+        carts.frCartNoStripeCustomer
+      )
+
+      expect(StripeProviderServiceMock.createCustomer).toHaveBeenCalledTimes(1)
+      expect(StripeProviderServiceMock.createCustomer).toHaveBeenCalledWith({
+        _id: IdMap.getId("vvd"),
+        first_name: "Virgil",
+        last_name: "Van Dijk",
+        email: "virg@vvd.com",
+        password_hash: "1234",
+        metadata: {},
+      })
+
+      expect(
+        StripeProviderServiceMock.updatePaymentIntentCustomer
+      ).toHaveBeenCalledTimes(1)
+      expect(
+        StripeProviderServiceMock.updatePaymentIntentCustomer
+      ).toHaveBeenCalledWith("cus_123456789_new_vvd")
+    })
+  })
+})

packages/medusa-payment-stripe/src/subscribers/cart.js

@@ -1,11 +1,71 @@
 class CartSubscriber {
-  constructor({ cartService, eventBusService }) {
+  constructor({
+    cartService,
+    customerService,
+    stripeProviderService,
+    eventBusService,
+  }) {
     this.cartService_ = cartService
+    this.customerService_ = customerService
+    this.stripeProviderService_ = stripeProviderService
     this.eventBus_ = eventBusService
 
     this.eventBus_.subscribe("cart.created", (data) => {
       console.log(data)
     })
+
+    this.eventBus_.subscribe("cart.customer_updated", async (cart) => {
+      await this.onCustomerUpdated(cart)
+    })
+  }
+
+  async onCustomerUpdated(cart) {
+    const { customer_id, payment_sessions } = cart
+
+    if (!payment_sessions) {
+      return Promise.resolve()
+    }
+
+    const customer = await this.customerService_.retrieve(customer_id)
+
+    const paymentIntent = await this.stripeProviderService_.retrievePayment(
+      cart
+    )
+
+    let stripeCustomer = await this.stripeProviderService_.retrieveCustomer(
+      customer.metadata.stripe_id
+    )
+
+    if (!stripeCustomer) {
+      stripeCustomer = await this.stripeProviderService_.createCustomer(
+        customer
+      )
+    }
+
+    if (stripeCustomer.id === paymentIntent.customer) {
+      return Promise.resolve()
+    }
+
+    if (!paymentIntent.customer) {
+      return this.stripeProviderService_.updatePaymentIntentCustomer(
+        stripeCustomer.id
+      )
+    }
+
+    if (stripeCustomer.id !== paymentIntent.customer) {
+      await this.stripeProviderService_.cancelPayment(paymentIntent.id)
+      const newPaymentIntent = await this.stripeProviderService_.createPayment(
+        cart
+      )
+
+      await this.cartService_.updatePaymentSession(
+        cart._id,
+        "stripe",
+        newPaymentIntent
+      )
+    }
+
+    return Promise.resolve()
   }
 }