Cleaning cart data on log out

Dealing with events

The VTEX shopping cart default behavior is to keep the cart alive until an order is placed. When this happens, a new cart is created. If a business rule requires a new cart every time a user logs out, we can use the Session Watcher to clear cart information.

It is not possible to get a brand new cart, but we can repurpose the current cart by removing any existing information on it.

This document will guide you on how to use the Session Watcher app to clean up an existing cart during logout.

Clients

VTEX IO Service Context gives you access to external clients. Clients are additional services with methods that give you access to different core applications. Here is a list of out-of-the-box client services available.

apps
assets
billing
billingMetrics
builder
events
id
licenseManager
masterdata
messagesGraphQL
metadata
registry
router
segment
settings
session
tenant
vbase
workspaces
catalogGraphQL
paymentProvider

You can always extend your App Clients if you need to give it access to external or internal providers.

Checkout Client

The VTEX IO Service Context does not have an out-of-the-box checkout client. The following steps will guide you on this setup of a client from our internal APIs.

Create a new ./node/clients/checkout.ts file where you can keep all the methods for the Checkout class. This class will extend JanusClient (VTEX’s internal router), you can import it from @vtex/api. It should look like the example below. Types are also imported from @vtex/api.


_10import type { InstanceOptions, IOContext } from ‘@’vtex/api’
_10import { JanusClient } from ‘@vtex/api’
_10
_10export class Checkout extends JanusClient {
_10    constructor(context: IOContext, options?: InstanceOptions) {
_10        super(context, { …options })
_10    }
_10}

These internal APIs are going through portal.vtexcommercestable.com.br/api/*, which means we need to declare it as an outbound-access in our manifest.json file under "policies".


_10"policies": [
_10    {
_10        "name": "outbound-access",
_10        "attrs": {
_10            "host": "portal.vtexcommercestable.com.br",
_10            "path": "/api/*"
_10        }
_10},

The same thing is required if you're accessing an external endpoint. Always add the host and path as an outbound-access.

Do not use protocol in the host (http, https). The host does not support wildcard within the address. It can be either fixed host or only * , never both. The path supports wildcard.

Now that you have an initial class setup, you can let your application know that it exists. Do this by importing it to the Clients constructor under ./node/clients/index.ts


_10import { IOClients } from ‘@vtex/api’
_10
_10import { Checkout } from ‘@vtex/api’
_10
_10// Extend the default IOClients implementation with our own custom clients.
_10export class Clients extends IOClients {
_10    public get checkout() {
_10        return this.getOrSet(‘checkout’, Checkout)
_10    }
_10}

The checkout client will now be available to our handler, just like the others.


_10{
_10    "name": "outbound-access",
_10    "attrs": {
_10        "host": "portal.vtexcommercestable.com.br",
_10        "path": "/checkout/changeToAnonymousUser/*"
_10}

Now you need to create your methods. The first thing you need is to change our orderForm (shopping cart) to anonymous. This will erase the clientProfileData, but will not remove the items from the cart, which will be done in another moment.

This method uses a path starting with /checkout, which means we need to include it to our policy by creating a new outbound-access entry. Back tocheckout.ts, add a new public method inside the Checkout class.


_10public changeToAnonymous = (orderFormId: string) => {
_10    return this.http.getRaw(`/checkout/changeToAnonymousUser/$\{orderFormId\}`, {
_10        metric ‘change-to-anonymous’,
_10    })
_10}

JanusClient gives you access to http and its methods. This example uses getRaw, which will return the entire response, including httpCode, headers, etc. If you do not need it, you can use only get instead. This metric property is used for logging, it is not not strictly necessary.

Create the other methods, orderForm, and updateItems, as shown below.


_19public orderForm = (orderFormId: string) => {
_19    return this.http.post(
_19        `/api/checkout/pub/orderForm/$\{orderFormId\}`,
_19        { expectedOrderFormSections: [‘items’] },
_19        {
_19            metric: ‘get-orderForm’,
_19        }
_19    )
_19}
_19
_19public updateItems = (orderFormId: string, orderItems: any) => {
_19    return this.http.post(
_19        `/api/checkout/pub/orderForm/$\{orderFormId\}/items/update`,
_19        { orderItems } ,
_19        {
_19            Metric: ‘update-orderForm-items’,
_19        }
_19    )
_19}

Clear Cart handler

Back to ./resolvers/index.ts load the checkout client from the context of our method clearCart and expose both orderFormId and email from the request body.

The logical flow is:

{"base64":" ","img":{"width":1672,"height":1428,"type":"png","mime":"image/png","wUnits":"px","hUnits":"px","length":218160,"url":"https://cdn.jsdelivr.net/gh/vtexdocs/dev-portal-content@main/images/vtex-io-documentation-cleaning-cart-data-on-log-out-0.png"}}

You should have code similar to the example below.


_70/* eslint-disable no-console */
_70import { json } from ‘co-body’
_70
_70export const resolvers = {
_70    Routes: {
_70        clearCart: async (ctx: Context) => {
_70            Const {
_70                req,
_70                clients: { checkout },
_70            } = ctx
_70
_70            const body: any = await json(req)
_70            const email = body?.authentication?.storeUserEmail?.value ?? null
_70            const orderFormId = body?.checkout?.orderFormId?.value ?? null
_70
_70            console.log(‘clearCart =>’, body)
_70
_70            ctx.set(‘Content-Type, ‘application/json’)
_70            ctx.set(‘Cache-Control’, ‘no-cache, no-store’) 
_70
_70            const res = {
_70                public: {
_70                    demo: {
_70                        value: email ? ‘User Authenticated’ : ‘User not authenticated’,
_70                    },
_70                },
_70            }
_70
_70            // If user is not authenticated, and we have an orderFormId
_70            if (!email && orderFormId) {
_70                // Get the current orderForm data
_70                const orderform: any await checkout.orderForm(orderFormId)
_70
_70                // Only if we have a user assigned to this orderForm
_70                if (orderForm?.clientProfileData?.email) {
_70                    // Change to anonymous
_70                    await checkout.changeToAnonymous(orderFormId).catch((err) => {
_70                        if (err.response.status >= 400) {
_70                            console.log(‘Cart response error =>’, err.response.statusText)
_70                        } else {
_70                            console.log(‘Cart response all good =>’, err.response.status)
_70                        }
_70                    })
_70
_70                    /*
_70                    * To remove items from the cart
_70                    * If we have items in the cart
_70                    */
_70                    if (orderForm?.items?.length) {
_70                        // Create a orderItems array with the item position and new quantity set to 0
_70                        const orderItems = orderForm.items.map((_: any, index: number) => {
_70                            return {
_70                                index,
_70                                quantity: 0,
_70                            }
_70                        })
_70
_70                        // Update the cart items with the new quantity
_70                        await checkout.updateItems(orderFormId, orderItems).catch((err) => {
_70                            console.log(‘Error removing all items =>’, err)
_70                        })
_70                    }
_70                }
_70            }
_70            
_70            ctx.response.body = res
_70            ctx.response.status = 200
_70        },
_70    },
_70}

Don't forget to change the vendor in your ./manifest.json file.

To link the app, run this command:


_10vtex link

If you wish, you can download this complete example