> ## Documentation Index
> Fetch the complete documentation index at: https://docs.membrane.agency/llms.txt
> Use this file to discover all available pages before exploring further.

# GraphQL API Mapping

The GraphQL API Mapping function type maps functions to GraphQL API endpoints.

It is defined like this:

```yaml theme={null}
type: graphql-api-mapping
mapping:
  query: |
    query GetContacts($limit: Int, $cursor: String) {
      contacts(first: $limit, after: $cursor) {
        edges {
          node {
            id
            firstName
            lastName
            email
          }
        }
        pageInfo {
          hasNextPage
          endCursor
        }
      }
    }
  variables:
    limit: 100
    cursor:
      $var: $.cursor
  responseMapping:
    records:
      $var: response.data.contacts.edges[*].node
```

## Format

* `query` – The GraphQL query or mutation string
* `variables` – Variables mapping for the GraphQL query
* `responseMapping` – Mapping to transform the GraphQL response

## Variables

* `credentials` – Authentication credentials from the current connection
* `parameters` – Function-level and collection-level parameters combined
* Function-specific input variables

For `responseMapping`:

* `response.data` – GraphQL response data
* `response.errors` – GraphQL response errors (if any)
* `response.extensions` – GraphQL response extensions (if any)

## Using in Connector Files

When used in connector files, the mapping is written in a separate file named `<function-name>.graphql.yml`.

For example:

```yaml theme={null}
# Function that lists contacts from an external API.
# File location: data/contacts/list.graphql.yml
query: |
  query GetContacts($limit: Int, $cursor: String) {
    contacts(first: $limit, after: $cursor) {
      edges {
        node {
          id
          firstName
          lastName
          email
        }
      }
      pageInfo {
        hasNextPage
        endCursor
      }
    }
  }
variables:
  limit: 100
  cursor:
    $var: $.cursor
responseMapping:
  records:
    $var: response.data.contacts.edges[*].node
  cursor:
    $cond:
      - $var: response.data.contacts.pageInfo.hasNextPage
      - $var: response.data.contacts.pageInfo.endCursor
      - null
```