@mtth/stl-graphql

Small GraphQL helpers that make schema-driven code easier to reason about: field selection checks, failure normalization, and type-mapping utilities.

Quickstart

pnpm add @mtth/stl-graphql

import {isFieldRequested, DeepRename} from '@mtth/stl-graphql';

// Skip expensive work unless the field is actually queried.
export const resolvers = {
  Query: {
    orders: (_src, _args, _ctx, info) => {
      if (isFieldRequested(info, ['edges', 'cursor'])) {
        // compute cursors only when needed
      }
      return fetchOrders();
    },
  },
};

// Map GraphQL result types into domain models with DeepRename.
type Models = {
  Order: {id: string; totalCents: number};
};
type OrderModel = DeepRename<OrderQuery['orders'][number], Models>;

Highlights

• isFieldRequested(info, path) inspects the selection set (including fragments and unions) so resolvers can short-circuit optional work.
• Type-level helpers such as DeepRename convert GraphQL generated types into domain models without writing repetitive mapping code.
• Shared error utilities align GraphQL errors with the standard @mtth/stl-errors format for consistent remediation payloads.
• Zero runtime dependencies beyond graphql, keeping bundle size and startup cost minimal.