I was testing my Shopify App recently and noticed that the Cart Transform merge is no longer working on version 2025-01.
In the 2025-01 version of the API says that you use are supposed to use the term merge in the Shopify Function but the most up to date and stable version of the api (2025-07) it says you are supposed to use linesMerge.
Below I put a code block of the following:
- My GraphQL input data
- The contents of my run.js file
- The output as Shown in my dev dashboard
If you take a look at my run.js code, you will see i am using the merge command at the end of the run function.
My code was working just a couple of weeks ago so I’m not sure what is going on. Please let me know how I can fix this.
//========== GraphQL Input Data for the Shopify Function
{
"cart": {
"lines": [
{
"id": "gid:\/\/shopify\/CartLine\/98a6b1a8-f7ec-401b-8287-b124c47c43fb",
"quantity": 1,
"bundleId": {
"value": "5"
}
},
{
"id": "gid:\/\/shopify\/CartLine\/c6456931-21c8-4f66-8704-eed9314783fa",
"quantity": 1,
"bundleId": {
"value": "5"
}
},
{
"id": "gid:\/\/shopify\/CartLine\/94714ab5-e458-4fe3-8d04-1c8ee44af690",
"quantity": 1,
"bundleId": {
"value": "5"
}
},
{
"id": "gid:\/\/shopify\/CartLine\/b04dc235-3904-4643-8640-1a58ae37d680",
"quantity": 1,
"bundleId": {
"value": "5"
}
}
]
},
"shop": {
"metafield": {
"value": "{\"parentVariantId\":\"gid:\/\/shopify\/ProductVariant\/51198624563487\",\"bundlesArray\":[{\"name\":\"Test Bundle\",\"id\":5,\"bundle_display_name\":\"\",\"bundle_checkout_title\":\"\",\"status\":\"active\",\"discount_type\":\"percentage\",\"static_discount_value\":\"20\",\"tiered_discounts\":\"[]\"}]}"
}
}
}
//========== Run.js file
export function run(input) {
// Stores cart lines grouped by their bundle ID property
const groupedItems = {};
const metafieldData = JSON.parse(input.shop.metafield.value)
const parentVariantId = metafieldData.parentVariantId
const bundlesArray = metafieldData.bundlesArray
const cartLines = input.cart.lines
//console.log("VALUE OF Metafield Data post-parse", "Parent Gid: " + parentVariantId, "\n", "Bundles Array", bundlesArray)
cartLines.forEach(line => {
const bundleId = line.bundleId
if(!bundleId?.value) return
//create a new grouping for the bundle id if it doesn't have one yet
if(!groupedItems[bundleId.value]){
groupedItems[bundleId.value] = []
}
groupedItems[bundleId.value].push(line)
})
console.log(JSON.stringify(groupedItems))
//Seems like this chunk of code is an array of arrays
const cartOperations = Object.values(groupedItems).map(group => {
const totalItemsInBundle = group.reduce((sum, line) => sum + line.quantity, 0);
const bundleId = group[0].bundleId.value;
const discountPercentage = calculatePercentageDiscount(bundlesArray, bundleId, totalItemsInBundle);
const updatedBundleTitle = overrideBundleTitle(bundlesArray, bundleId);
const lineItems = group.map(line => {
return {
cartLineId: line.id,
quantity: line.quantity
}
})
// console.log("Value of Line Items", JSON.stringify(lineItems))
// console.log("Discount: " + discountPercentage)
// console.log("Updated Title: " + updatedBundleTitle)
return{
merge: {
cartLines: lineItems,
//^ Variant ID of the Parent Product for the Bundler Cart Transform
parentVariantId: parentVariantId,
price: {
percentageDecrease: {
value: discountPercentage
}
},
//Conditional object spread
...(updatedBundleTitle && { title: updatedBundleTitle })
}
}
})
return {
operations: cartOperations
}
};
function calculatePercentageDiscount(bundlesArray, bundleId, totalItemsInBundle) {
const bundleConfig = bundlesArray.find(bundle => bundle.id == bundleId)
if (!bundleConfig) {
return 0;
}
if (bundleConfig.discount_type === "percentage") {
return parseFloat(bundleConfig.static_discount_value) || 0;
}
if (bundleConfig.discount_type === "tiered_percentage") {
const tieredDiscounts = JSON.parse(bundleConfig.tiered_discounts);
const sortedTiers = tieredDiscounts.sort((a, b) => b.minItems - a.minItems);
const applicableTier = sortedTiers.find(tier => totalItemsInBundle >= parseInt(tier.minItems));
if (applicableTier) {
return parseFloat(applicableTier.discount) || 0;
}
}
return 0;
}
function overrideBundleTitle(bundlesArray, bundleId) {
const bundleConfig = bundlesArray.find(bundle => bundle.id == bundleId);
return bundleConfig?.bundle_checkout_title || null;
}
//========= Result of the Shopify Function:
{
"operations": [
{
"linesMerge": {
"cartLines": [
{
"cartLineId": "gid:\/\/shopify\/CartLine\/98a6b1a8-f7ec-401b-8287-b124c47c43fb",
"quantity": 1
},
{
"cartLineId": "gid:\/\/shopify\/CartLine\/c6456931-21c8-4f66-8704-eed9314783fa",
"quantity": 1
},
{
"cartLineId": "gid:\/\/shopify\/CartLine\/94714ab5-e458-4fe3-8d04-1c8ee44af690",
"quantity": 1
},
{
"cartLineId": "gid:\/\/shopify\/CartLine\/b04dc235-3904-4643-8640-1a58ae37d680",
"quantity": 1
}
],
"parentVariantId": "gid:\/\/shopify\/ProductVariant\/51198624563487",
"price": {
"percentageDecrease": {
"value": 20
}
}
}
}
]
}
And this what the result looks like in checkout:
