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# Method name: updateLineItemsQuantity(_id: string, lineItems: Array<LineItemQuantityUpdate>)

# Method package: wixEcomBackend

# Method menu location: wixEcomBackend --> checkout --> updateLineItemsQuantity

# Method Link: https://dev.wix.com/docs/velo/apis/wix-ecom-backend/checkout/update-line-items-quantity.md

# Method Description:

Updates the quantity of one or more line items in a checkout.

This endpoint is only for updating the quantity of line items. To entirely remove a line item from
the checkout, use [`removeLineItems()`](#removelineitems).
To add a new line item to the checkout, use [`addToCheckout()`](#addtocheckout).

This endpoint checks the amount of stock remaining for this line item. If the specified `quantity`
is greater than the remaining stock, then the `quantity` returned in the response is the total amount
of remaining stock.



# Method Code Examples:

*** Note: do not assume any prop names or enum values other than the ones in the example.

## Update the quantity of line items in a checkout

```javascript
import { checkout } from 'wix-ecom-backend';

/* Sample checkoutId value: '21fe558e-21a0-4cff-a49b-a4ccb0f7414d'
 *
 * Sample listItems value:
 * {
 *   _id: '00000000-0000-0000-0000-000000000001',
 *   quantity: 10
 * }
 */

export async function myUpdateQuantityFunction(checkoutId, lineItems) {
  try {
    const updatedCheckout = await checkout.updateLineItemsQuantity(checkoutId, lineItems);

    const firstUpdatedLineItem = updatedCheckout.checkout.lineItems[0];
    const updatedQuantity = firstUpdatedLineItem.quantity;

    console.log('Success! The updated quantity for the first line item is:', updatedQuantity);
    return updatedCheckout;
  } catch (error) {
    console.error(error);
  }
}

/* Promise resolves to:
 * {
 *   "checkout": {
 *     "_id": "21fe558e-21a0-4cff-a49b-a4ccb0f7414d",
 *     "lineItems": [
 *       {
 *         "_id": "00000000-0000-0000-0000-000000000001",
 *         "quantity": 10,
 *         "catalogReference": {
 *           "catalogItemId": "c8539b66-7a44-fe18-affc-afec4be8562a",
 *           "appId": "215238eb-22a5-4c36-9e7b-e7c08025e04e"
 *         },
 *         "productName": {
 *           "original": "Shirt",
 *           "translated": "Shirt"
 *         },
 *         "url": "https://example.wixsite.com/product-page/shirt",
 *         "price": {
 *           "amount": "10",
 *           "convertedAmount": "10",
 *           "formattedAmount": "$10.00",
 *           "formattedConvertedAmount": "$10.00"
 *         },
 *         "lineItemPrice": {
 *           "amount": "100",
 *           "convertedAmount": "100",
 *           "formattedAmount": "$100.00",
 *           "formattedConvertedAmount": "$100.00"
 *         },
 *         "fullPrice": {
 *           "amount": "10",
 *           "convertedAmount": "10",
 *           "formattedAmount": "$10.00",
 *           "formattedConvertedAmount": "$10.00"
 *         },
 *         "priceBeforeDiscounts": {
 *           "amount": "10",
 *           "convertedAmount": "10",
 *           "formattedAmount": "$10.00",
 *           "formattedConvertedAmount": "$10.00"
 *         },
 *         "totalPriceAfterTax": {
 *           "amount": "100",
 *           "convertedAmount": "100",
 *           "formattedAmount": "$100.00",
 *           "formattedConvertedAmount": "$100.00"
 *         },
 *         "totalPriceBeforeTax": {
 *           "amount": "100",
 *           "convertedAmount": "100",
 *           "formattedAmount": "$100.00",
 *           "formattedConvertedAmount": "$100.00"
 *         },
 *         "taxDetails": {
 *           "taxableAmount": {
 *             "amount": "100",
 *             "convertedAmount": "100",
 *             "formattedAmount": "$100.00",
 *             "formattedConvertedAmount": "$100.00"
 *           },
 *           "taxRate": "0",
 *           "totalTax": {
 *             "amount": "0",
 *             "convertedAmount": "0",
 *             "formattedAmount": "$0.00",
 *             "formattedConvertedAmount": "$0.00"
 *           },
 *           "rateBreakdown": []
 *         },
 *         "discount": {
 *           "amount": "0",
 *           "convertedAmount": "0",
 *           "formattedAmount": "$0.00",
 *           "formattedConvertedAmount": "$0.00"
 *         },
 *         "descriptionLines": [],
 *         "media": "wix:image://v1/3c76e2_c5331f937348492a97df87b0a3b34ea4~mv2.jpg/3c76e2_c5331f937348492a97df87b0a3b34ea4~mv2.jpg#originWidth=1000&originHeight=1000",
 *         "availability": {
 *           "status": "AVAILABLE"
 *         },
 *         "physicalProperties": {
 *           "sku": "364115376135191",
 *           "shippable": true
 *         },
 *         "couponScopes": [
 *           {
 *             "namespace": "stores",
 *             "group": {
 *               "name": "collection",
 *               "entityId": "00000000-000000-000000-000000000001"
 *             }
 *           },
 *           {
 *             "namespace": "stores",
 *             "group": {
 *               "name": "product",
 *               "entityId": "c8539b66-7a44-fe18-affc-afec4be8562a"
 *             }
 *           }
 *         ],
 *         "itemType": {
 *           "preset": "PHYSICAL"
 *         },
 *         "paymentOption": "FULL_PAYMENT_ONLINE",
 *         "rootCatalogItemId": "c8539b66-7a44-fe18-affc-afec4be8562a"
 *       }
 *     ],
 *     "shippingInfo": {
 *       "carrierServiceOptions": []
 *     },
 *     "buyerNote": "Updated note.",
 *     "buyerInfo": {
 *       "contactId": "a4bc8d90-a91b-467f-a775-77d65dd0442e",
 *       "email": "testing3@example.com",
 *       "memberId": "ea3d74df-b7dc-4ca1-a7c9-c416b9017a86"
 *     },
 *     "conversionCurrency": "USD",
 *     "priceSummary": {
 *       "subtotal": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "shipping": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "tax": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "discount": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "total": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "additionalFees": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       }
 *     },
 *     "calculationErrors": {
 *       "orderValidationErrors": []
 *     },
 *     "appliedDiscounts": [],
 *     "customFields": [],
 *     "weightUnit": "LB",
 *     "currency": "USD",
 *     "channelType": "WEB",
 *     "siteLanguage": "en",
 *     "buyerLanguage": "en",
 *     "completed": false,
 *     "taxIncludedInPrice": false,
 *     "createdBy": {
 *       "memberId": "ea3d74df-b7dc-4ca1-a7c9-c416b9017a86"
 *     },
 *     "_createdDate": "2023-02-22T15:49:04.627Z",
 *     "_updatedDate": "2023-04-30T05:51:13.309Z",
 *     "payNow": {
 *       "subtotal": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "shipping": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "tax": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "discount": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "total": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "additionalFees": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       }
 *     },
 *     "payLater": {
 *       "subtotal": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "shipping": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "tax": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "discount": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "total": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "additionalFees": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       }
 *     },
 *     "membershipOptions": {
 *       "eligibleMemberships": [],
 *       "invalidMemberships": [],
 *       "selectedMemberships": {
 *         "memberships": []
 *       }
 *     },
 *     "additionalFees": [],
 *     "payNowTotalAfterGiftCard": {
 *       "amount": "100",
 *       "convertedAmount": "100",
 *       "formattedAmount": "$100.00",
 *       "formattedConvertedAmount": "$100.00"
 *     }
 *   }
 * }
 */

```

## Update the quantity of line items in a checkout (export from backend code)

```javascript
import { Permissions, webMethod } from 'wix-web-module';
import { checkout } from 'wix-ecom-backend';

/* Sample checkoutId value: '21fe558e-21a0-4cff-a49b-a4ccb0f7414d'
 *
 * Sample listItems value:
 * {
 *   _id: '00000000-0000-0000-0000-000000000001',
 *   quantity: 10
 * }
 */

export const myUpdateQuantityFunction = webMethod(Permissions.Anyone, async (checkoutId, lineItems) => {
  try {
    const updatedCheckout = await checkout.updateLineItemsQuantity(checkoutId, lineItems);

    const firstUpdatedLineItem = updatedCheckout.checkout.lineItems[0];
    const updatedQuantity = firstUpdatedLineItem.quantity;

    console.log('Success! The updated quantity for the first line item is:', updatedQuantity);
    return updatedCheckout;
  } catch (error) {
    console.error(error);
  }
});

/* Promise resolves to:
 * {
 *   "checkout": {
 *     "_id": "21fe558e-21a0-4cff-a49b-a4ccb0f7414d",
 *     "lineItems": [
 *       {
 *         "_id": "00000000-0000-0000-0000-000000000001",
 *         "quantity": 10,
 *         "catalogReference": {
 *           "catalogItemId": "c8539b66-7a44-fe18-affc-afec4be8562a",
 *           "appId": "215238eb-22a5-4c36-9e7b-e7c08025e04e"
 *         },
 *         "productName": {
 *           "original": "Shirt",
 *           "translated": "Shirt"
 *         },
 *         "url": "https://example.wixsite.com/product-page/shirt",
 *         "price": {
 *           "amount": "10",
 *           "convertedAmount": "10",
 *           "formattedAmount": "$10.00",
 *           "formattedConvertedAmount": "$10.00"
 *         },
 *         "lineItemPrice": {
 *           "amount": "100",
 *           "convertedAmount": "100",
 *           "formattedAmount": "$100.00",
 *           "formattedConvertedAmount": "$100.00"
 *         },
 *         "fullPrice": {
 *           "amount": "10",
 *           "convertedAmount": "10",
 *           "formattedAmount": "$10.00",
 *           "formattedConvertedAmount": "$10.00"
 *         },
 *         "priceBeforeDiscounts": {
 *           "amount": "10",
 *           "convertedAmount": "10",
 *           "formattedAmount": "$10.00",
 *           "formattedConvertedAmount": "$10.00"
 *         },
 *         "totalPriceAfterTax": {
 *           "amount": "100",
 *           "convertedAmount": "100",
 *           "formattedAmount": "$100.00",
 *           "formattedConvertedAmount": "$100.00"
 *         },
 *         "totalPriceBeforeTax": {
 *           "amount": "100",
 *           "convertedAmount": "100",
 *           "formattedAmount": "$100.00",
 *           "formattedConvertedAmount": "$100.00"
 *         },
 *         "taxDetails": {
 *           "taxableAmount": {
 *             "amount": "100",
 *             "convertedAmount": "100",
 *             "formattedAmount": "$100.00",
 *             "formattedConvertedAmount": "$100.00"
 *           },
 *           "taxRate": "0",
 *           "totalTax": {
 *             "amount": "0",
 *             "convertedAmount": "0",
 *             "formattedAmount": "$0.00",
 *             "formattedConvertedAmount": "$0.00"
 *           },
 *           "rateBreakdown": []
 *         },
 *         "discount": {
 *           "amount": "0",
 *           "convertedAmount": "0",
 *           "formattedAmount": "$0.00",
 *           "formattedConvertedAmount": "$0.00"
 *         },
 *         "descriptionLines": [],
 *         "media": "wix:image://v1/3c76e2_c5331f937348492a97df87b0a3b34ea4~mv2.jpg/3c76e2_c5331f937348492a97df87b0a3b34ea4~mv2.jpg#originWidth=1000&originHeight=1000",
 *         "availability": {
 *           "status": "AVAILABLE"
 *         },
 *         "physicalProperties": {
 *           "sku": "364115376135191",
 *           "shippable": true
 *         },
 *         "couponScopes": [
 *           {
 *             "namespace": "stores",
 *             "group": {
 *               "name": "collection",
 *               "entityId": "00000000-000000-000000-000000000001"
 *             }
 *           },
 *           {
 *             "namespace": "stores",
 *             "group": {
 *               "name": "product",
 *               "entityId": "c8539b66-7a44-fe18-affc-afec4be8562a"
 *             }
 *           }
 *         ],
 *         "itemType": {
 *           "preset": "PHYSICAL"
 *         },
 *         "paymentOption": "FULL_PAYMENT_ONLINE",
 *         "rootCatalogItemId": "c8539b66-7a44-fe18-affc-afec4be8562a"
 *       }
 *     ],
 *     "shippingInfo": {
 *       "carrierServiceOptions": []
 *     },
 *     "buyerNote": "Updated note.",
 *     "buyerInfo": {
 *       "contactId": "a4bc8d90-a91b-467f-a775-77d65dd0442e",
 *       "email": "testing3@example.com",
 *       "memberId": "ea3d74df-b7dc-4ca1-a7c9-c416b9017a86"
 *     },
 *     "conversionCurrency": "USD",
 *     "priceSummary": {
 *       "subtotal": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "shipping": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "tax": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "discount": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "total": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "additionalFees": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       }
 *     },
 *     "calculationErrors": {
 *       "orderValidationErrors": []
 *     },
 *     "appliedDiscounts": [],
 *     "customFields": [],
 *     "weightUnit": "LB",
 *     "currency": "USD",
 *     "channelType": "WEB",
 *     "siteLanguage": "en",
 *     "buyerLanguage": "en",
 *     "completed": false,
 *     "taxIncludedInPrice": false,
 *     "createdBy": {
 *       "memberId": "ea3d74df-b7dc-4ca1-a7c9-c416b9017a86"
 *     },
 *     "_createdDate": "2023-02-22T15:49:04.627Z",
 *     "_updatedDate": "2023-04-30T05:51:13.309Z",
 *     "payNow": {
 *       "subtotal": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "shipping": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "tax": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "discount": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "total": {
 *         "amount": "100",
 *         "convertedAmount": "100",
 *         "formattedAmount": "$100.00",
 *         "formattedConvertedAmount": "$100.00"
 *       },
 *       "additionalFees": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       }
 *     },
 *     "payLater": {
 *       "subtotal": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "shipping": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "tax": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "discount": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "total": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       },
 *       "additionalFees": {
 *         "amount": "0",
 *         "convertedAmount": "0",
 *         "formattedAmount": "$0.00",
 *         "formattedConvertedAmount": "$0.00"
 *       }
 *     },
 *     "membershipOptions": {
 *       "eligibleMemberships": [],
 *       "invalidMemberships": [],
 *       "selectedMemberships": {
 *         "memberships": []
 *       }
 *     },
 *     "additionalFees": [],
 *     "payNowTotalAfterGiftCard": {
 *       "amount": "100",
 *       "convertedAmount": "100",
 *       "formattedAmount": "$100.00",
 *       "formattedConvertedAmount": "$100.00"
 *     }
 *   }
 * }
 */

```

---