register dataloaders, get dataloaders and so on

registerDataLoaders.ts

export type GetLoader = () => DataLoader<string, any>;
type Dataloaders = {
  [loader: string]: GetLoader;
};

const dataloaders: Dataloaders = {};
export const registerDataLoader = (name: string, getLoader: GetLoader) => {
  dataloaders[name] = getLoader;
};

export const getDataloaders = (): GraphQLDataLoaders => Object.keys(dataloaders).reduce(
  (acc, loaderKey) => ({
    ...acc,
    [loaderKey]: dataloaders[loaderKey](),
  }),
  {},
);