Shopify Storefront API. adding item to cart

Question

Im using the Shopify storefront API to query for a list of products and add a selected item to the cart.

I am able to use API to list all the products, and returns the variantID for the product found

Here is the GraphQL query to return a product

{
  shop {
    name
    products(first: 1, query:"title=configurable-handmade-concrete-ball") {
      edges {
        cursor
        node {
          id
          title
          handle
          variants(first:1) {
            edges {
              node {
                id
                title
              }
            }
          }
        }
      }
    }
  }
}

and the result

{
  "data": {
    "shop": {
      "name": "VonageTest",
      "products": {
        "edges": [
          {
            "cursor": "eyJvZmZzZXQiOjF9",
            "node": {
              "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0LzEwNTU2MjYxNTE4",
              "title": "Configurable Handmade Concrete Ball",
              "handle": "configurable-handmade-concrete-ball",
              "variants": {
                "edges": [
                  {
                    "node": {
                      "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0VmFyaWFudC80MDIwOTc1NjQzMA==",
                      "title": "Default Title"
                    }
                  }
                ]
              }
            }
          }
        ]
      }
    }
  }
}

In order to add items to the cart, you can make a POST request that contains the following

https://{store_name}.myshopify.com/cart/{variant_id}

performing this call using the variant_id from the graphQL response returns a 404. But if you get the variant_id from the page, you can inspect the xml page and use the variant_id there This shows how that is done https://help.shopify.com/themes/customization/cart/use-permalinks-to-preload-cart

so why does the variant_id from the storefront API different from the variant_id on the page?

Answer 1

I just encountered the same problem and was finally able to track down the answer in the Shopify GraphQL docs - https://help.shopify.com/api/storefront-api/reference/scalar/id

Basically, the id returned in Shopify GraphQL responses is a base64-encoded representation of the actual Shopify id. So if you base64-decode the variant id from the result you posted, the value is gid://shopify/ProductVariant/40209756430

You would need to parse the numerical id from the end of that value and that would be the id that Shopify uses for all other APIs.

Answer 2

I have implemented the shopify shop and cart using GraphQL provided by shopify . Follow these steps -

1. Create Storefront.CheckoutCreateInput() object.
2. Add lineItems to it - Storefront.CheckoutLineItemInput(quantity,new ID(productVariantId)); Don't be confused with productId with productVariantID . You need to use productVariantId here

3. Now you need to mutate line items on CheckoutCreateInput object -

   Storefront.MutationQuery query = Storefront.mutation(mutationQuery -> mutationQuery
           .checkoutCreate(checkoutCreateInputObject, createPayloadQuery -> createPayloadQuery
                   .checkout(checkoutQuery -> checkoutQuery
                           .webUrl()
                   )
                   .userErrors(userErrorQuery -> userErrorQuery
                           .field()
                           .message()
                   )
           )
   );
   

You will get a checkout Id here , save it .

4.Now you need to create Storefront.MailingAddressInput() , taking inputs from user (city , state , email , name etc).Then you need to update this mailing address on CheckoutCreateInput() object like this checkoutCreateInputObj.setShippingAddress() .

5.Now you need to fetch Shipping Rates -

            Storefront.QueryRootQuery query = Storefront.query(rootQuery -> rootQuery
            .node(checkoutId, nodeQuery -> nodeQuery
                    .onCheckout(checkoutQuery -> checkoutQuery
                            .availableShippingRates(availableShippingRatesQuery -> availableShippingRatesQuery
                                    .ready()
                                    .shippingRates(shippingRateQuery -> shippingRateQuery
                                            .handle()
                                            .price()
                                            .title()
                                    )
                            )
                    )
            )
    );

6. Fetch the total price user need to pay -

   Storefront.QueryRootQuery query = Storefront.query(rootQuery -> rootQuery
           .node(checkoutId, nodeQuery -> nodeQuery
                   .onCheckout(checkoutQuery -> checkoutQuery
                           .subtotalPrice()
                           .totalPrice()
                           .availableShippingRates(availableShippingRateQuery -> availableShippingRateQuery
                               .ready()
                                   .shippingRates(shippingRateQuery -> shippingRateQuery
                                           .price()
                                   )
                           )
                   )
           )
   );
   

7. Apply coupons if any -

   Storefront.MutationQuery query = Storefront.mutation(mutationQuery -> mutationQuery
           .checkoutDiscountCodeApply(couponCode,checkoutId,discountQuery -> discountQuery
                   .userErrors(userErrorQuery -> userErrorQuery
                           .message()
                           .field()
                   )
                   .checkout(checkoutQuery -> checkoutQuery
                           .webUrl()
                           .totalPrice()
                           .appliedGiftCards(giftCardQuery -> giftCardQuery
                               .amountUsed()
                                   .balance()
                           )
                   )
           )
   );
   

8. Get the cardVaultURL -

   Storefront.QueryRootQuery query = Storefront.query(rootQueryBuilder ->
           rootQueryBuilder
                   .shop(shopQueryBuilder ->
                           shopQueryBuilder
                                   .paymentSettings(paymentQueryBuilder -> paymentQueryBuilder
                                           .cardVaultUrl()
                                   )
                   )
   );
   

9. Get the payment token -

   CardClient cardClient = new CardClient();
   CreditCard creditCard = CreditCard.builder()
           .firstName(firstName)
           .lastName(lastName)
           .number(cardNumber)
           .expireMonth(expiryMonth)
           .expireYear(expiryYear)
           .verificationCode(cvv)
           .build();
   

   cardClient.vault(creditCard, cardVaultURL).enqueue(new CreditCardVaultCall.Callback() { @Override public void onResponse(@NonNull String token) { // proceed to complete checkout with token paymentToken = token; }

       @Override public void onFailure(@NonNull IOException error) {
           // handle error
           Log.d("error occured are just ",error.toString());
       }
   });
   

10. Charge amount -

    String idempotencyKey = UUID.randomUUID().toString();
        Storefront.CreditCardPaymentInput input = new Storefront.CreditCardPaymentInput(amount, idempotencyKey, billingAddress,
                paymentToken);
    
    
    
        Storefront.MutationQuery query = Storefront.mutation(mutationQuery -> mutationQuery
                .checkoutCompleteWithCreditCard(shopifyHandler.checkoutId, input, payloadQuery -> payloadQuery
                        .payment(paymentQuery -> paymentQuery
                                .ready()
                                .errorMessage()
                        )
                        .checkout(checkoutQuery -> checkoutQuery
                                .ready()
                        )
                        .userErrors(userErrorQuery -> userErrorQuery
                                .field()
                                .message()
                        )
                )
        );