Problem generating discount code

[santiago_fama]

I’m trying to implement a system on my website where I can create discount codes. I’m using Next.js 14 with the app router, and I’m making direct API calls via fetch. I followed the example from the documentation, but I keep encountering the same issue:

“DiscountCodeBasicInput isn’t a defined input type (on $basicCodeDiscount)”

I’ve also tried using GraphiQL within Shopify, and it works perfectly there, so I don’t think it’s a connection problem. My connection to Shopify is correct since I’m able to retrieve products, use the cart, and perform other functions without any issues. Has anyone seen this error before, or can offer some guidance?

This is my function that calls Shopify Fetch and provides the variables.

export async function createDiscountCode(
  email: string
): Promise<{ success: boolean; code?: string; error?: string }> {
  const code = generateUniqueCode();
  try {
    const res = await shopifyFetch<ShopifyCreateDiscountCodeOperation>({
      query: createDiscountCodeMutation,
      variables: {
        basicCodeDiscount: {
          title: "20% off all items during the summer of 2022",
          code: code,
          startsAt: "2022-06-21T00:00:00Z",
          endsAt: "2022-09-21T00:00:00Z",
          customerSelection: {
            all: true
          },
          customerGets: {
            value: {
              percentage: 0.2
            },
            items: {
              all: true
            }
          },
          appliesOncePerCustomer: true
        }        
      },
      cache: 'no-store'
    });

    if (res.body.data.discountCodeBasicCreate.userErrors.length > 0) {
      throw new Error(res.body.data.discountCodeBasicCreate.userErrors[0]!.message);
    }

    const createdCode =
      res.body.data.discountCodeBasicCreate.codeDiscountNode.codeDiscount.codes.edges[0]!.node;

    return { success: true, code: createdCode };
  } catch (error) {
    console.error('Error creating discount code:', error);
    return { success: false, error: 'Failed to create discount code' };
  }
}

and the shopifyFetch function:

export async function shopifyFetch<T>({
  cache = 'force-cache',
  headers,
  query,
  tags,
  variables
}: {
  cache?: RequestCache;
  headers?: HeadersInit;
  query: string;
  tags?: string[];
  variables?: ExtractVariables<T>;
}): Promise<{ status: number; body: T } | never> {
  try {
    const result = await fetch(endpoint, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'X-Shopify-Storefront-Access-Token': key,
        ...headers
      },
      body: JSON.stringify({
        ...(query && { query }),
        ...(variables && { variables })
      }),
      cache,
      ...(tags && { next: { tags } })
    });

    const body = await result.json();

    if (body.errors) {
      throw body.errors[0];
    }

    return {
      status: result.status,
      body
    };
  } catch (e) {
    if (isShopifyError(e)) {
      throw {
        cause: e.cause?.toString() || 'unknown',
        status: e.status || 500,
        message: e.message,
        query
      };
    }

    throw {
      error: e,
      query
    };
  }
}

and finally the query:

export const createDiscountCodeMutation = `
  mutation discountCodeBasicCreate($basicCodeDiscount: DiscountCodeBasicInput!) {
  discountCodeBasicCreate(basicCodeDiscount: $basicCodeDiscount) {
    codeDiscountNode {
      codeDiscount {
        ... on DiscountCodeBasic {
          title
          codes(first: 10) {
            nodes {
              code
            }
          }
          startsAt
          endsAt
          customerSelection {
            ... on DiscountCustomerAll {
              allCustomers
            }
          }
          customerGets {
            value {
              ... on DiscountPercentage {
                percentage
              }
            }
            items {
              ... on AllDiscountItems {
                allItems
              }
            }
          }
          appliesOncePerCustomer
        }
      }
    }
    userErrors {
      field
      code
      message
    }
  }
}
`;