@pothos/plugin-add-graphql/src/utils.ts

A Pothos plugin for adding existing GraphQL types to a Pothos schema

import { createContextCache, type SchemaTypes } from '@pothos/core';
import {
  type GraphQLNamedType,
  isEnumType,
  isInputObjectType,
  isInterfaceType,
  isObjectType,
  isScalarType,
  isUnionType,
} from 'graphql';

export const referencedTypes = createContextCache(() => new Set<GraphQLNamedType>());

export function addTypeToSchema<Types extends SchemaTypes>(
  builder: PothosSchemaTypes.SchemaBuilder<Types>,
  type: GraphQLNamedType,
) {
  if (builder.configStore.hasConfig(type.name as never)) {
    return;
  }

  if (isObjectType(type)) {
    builder.addGraphQLObject(type);
  } else if (isInterfaceType(type)) {
    builder.addGraphQLInterface(type);
  } else if (isUnionType(type)) {
    builder.addGraphQLUnion(type);
  } else if (isEnumType(type)) {
    builder.addGraphQLEnum(type);
  } else if (isInputObjectType(type)) {
    builder.addGraphQLInput(type);
  } else if (isScalarType(type)) {
    builder.addScalarType(type.name as never, type);
  }
}
export function addReferencedType<Types extends SchemaTypes>(
  builder: PothosSchemaTypes.SchemaBuilder<Types>,
  type: GraphQLNamedType,
) {
  if (referencedTypes(builder).has(type)) {
    return;
  }

  builder.configStore.onPrepare(() => addTypeToSchema(builder, type));
}