import * as graphql from 'graphql';

/*
 * ExpressApolloOptions
 *
 * - schema: an executable GraphQL schema used to fulfill requests.
 * - (optional) formatError: Formatting function applied to all errors before response is sent
 * - (optional) rootValue: rootValue passed to GraphQL execution
 * - (optional) context: the context passed to GraphQL execution
 * - (optional) logFunction: a function called for logging events such as execution times
 * - (optional) formatParams: a function applied to the parameters of every invocation of runQuery
 * - (optional) validationRules: extra validation rules applied to requests
 * - (optional) formatResponse: a function applied to each graphQL execution result
 *
 */
interface ApolloOptions {
  schema: graphql.GraphQLSchema;
  formatError?: Function;
  rootValue?: any;
  context?: any;
  logFunction?: Function;
  formatParams?: Function;
  validationRules?: Array<graphql.ValidationRule>;
  formatResponse?: Function;
}

export default ApolloOptions;