Applying a discount

NOTE: Only one discount can be applied to an order.

A discount can be applied to a cart in one of two ways:

Automatic Discounts

Automatic discounts are applied at checkout without the customer needing to take any action.

To check if a discount exists simply run this mutation:

mutation applyAutomaticDiscount($cartId: ID!) {
  discount: applyAutomaticDiscount(cartId: $cartId) {
    discountCode
    totalDiscount
    discountId
    value
    target
    trigger
    type
  }
}

If no discounts exist to apply this error will return:

{
  "data": {
    "discount": null
  },
  "errors": [
    {
      "locations": [
        {
          "column": 0,
          "line": 2
        }
      ],
      "message": "No eligible automatic discounts for cart",
      "path": [
        "discount"
      ]
    }
  ]
}

If an eligible discount is found it will return the discount details:

{
  "data": {
    "discount": {
      "discountCode": "XXXXXXXXXX",
      "discountId": "92a7600b-bb22-4b24-8cdb-a71f02d50007",
      "target": "all_products",
      "totalDiscount": "6.75",
      "trigger": "automatic",
      "type": "percentage",
      "value": "50"
    }
  }
}

And these will be applied to the cart

Manual Discounts

Manual discounts are discounts driven by a code entered on checkout.

If a customer enters a code you can check and apply the discount using this mutation:

mutation applyDiscount($cartId: ID!, $discountCode: String) {
  discount: applyDiscount(cartId: $cartId, discountCode: $discountCode) {
    discountCode
    totalDiscount
    discountId
    value
    target
    trigger
    type
    warnings
  }
}

Example variables:

{
  "discountCode": "CODE",
  "cartId": "65b54e63-71ab-439b-8f2c-5726a34daa97"
}

Successful response

{
  "data": {
    "discount": {
      "discountCode": "CODE",
      "discountId": "820143ab-40cc-4516-88af-963ea24d14c7",
      "target": "all_products",
      "totalDiscount": "7.00",
      "trigger": "manual",
      "type": "percentage",
      "value": "100"
    }
  }
}

Error Response

{
  "data": {
    "discount": null
  },
  "errors": [
    {
      "locations": [
        {
          "column": 0,
          "line": 2
        }
      ],
      "message": "Order must be a minimum of £5.00",
      "path": [
        "discount"
      ]
    }
  ]
}

Response with warnings

{
  "data": {
    "discount": {
      "warnings": [
        "DISCOUNT_REQUIRES_CUSTOMER_LOGIN"
      ]
    }
  }
}

Types of warnings:

Warning	Meaning
DISCOUNT_REQUIRES_CUSTOMER_LOGIN	The discount requires a customer to be logged in before it can be validated. Once logged in they will be rejected if the customer does not meet the discount's criteria.

Removing a discount

use this to remove a discount from a cart:

mutation removeDiscount($cartId: ID!) {
  cart: removeDiscount(cartId: $cartId) {
    id
  }
}