graphql-request with automatic parsing of DateTime

client.ts

import { GraphQLClient } from 'graphql-request';
import { gqlSerializer } from './serializer.ts'

const gqlClient = new GraphQLClient(url, {
  credentials: 'include',
  mode: 'cors',
  jsonSerializer: gqlSerializer,
});

serializer.ts

import { GraphQLDateTime } from 'graphql-scalars';

const RFC_3339_REGEX =
  /^(\d{4}-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])T([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]|60))(\.\d{1,})?(([Z])|([+|-]([01][0-9]|2[0-3]):[0-5][0-9]))$/;

const isDateTimeString = (value: string) => RFC_3339_REGEX.test(value);

const parse = (value: unknown): unknown => {
  if (value === null) {
    return value;
  }
  if (typeof value === 'string') {
    if (isDateTimeString(value)) {
      return GraphQLDateTime.parseValue(value);
    }
  }
  if (typeof value === 'object') {
    if (Array.isArray(value)) {
      return value.map(parse);
    }
    return Object.fromEntries(
      Object.entries(value).map(([k, v]) => {
        return [k, parse(v)];
      }),
    );
  }

  return value;
};

const stringify = (value: unknown): unknown => {
  if (value === null) {
    return value;
  }
  if (value instanceof Date) {
    return GraphQLDateTime.serialize(value);
  }
  if (typeof value === 'object') {
    if (Array.isArray(value)) {
      return value.map(stringify);
    }
    return Object.fromEntries(
      Object.entries(value).map(([k, v]) => {
        return [k, stringify(v)];
      }),
    );
  }

  return value;
};


export const gqlSerializer = {
  parse: <T = any>(jsonStr: string): T => {
    const jsonValue = JSON.parse(jsonStr);
    return parse(jsonValue) as T;
  },

  stringify: <T = unknown>(obj: T): string => {
    const objWithoutDate = stringify(obj);
    return JSON.stringify(objWithoutDate);
  },
};