@graphql-tools/wrap

What is @graphql-tools/wrap?

The @graphql-tools/wrap package is part of the GraphQL Tools ecosystem, which provides a set of utilities for working with GraphQL schemas. Specifically, @graphql-tools/wrap allows you to transform, extend, and modify existing GraphQL schemas in a flexible and powerful way. This can be particularly useful for gateway services, schema stitching, or when you need to adjust a third-party GraphQL API to fit your application's needs.

What are @graphql-tools/wrap's main functionalities?

Schema Wrapping

This feature allows you to create a new schema by wrapping an existing one, applying various transformations such as renaming types. This is useful for integrating external schemas without causing naming conflicts.

const { wrapSchema, RenameTypes } = require('@graphql-tools/wrap');
const remoteSchema = await introspectSchema(fetcher);
const wrappedSchema = wrapSchema({
  schema: remoteSchema,
  transforms: [new RenameTypes((name) => `Prefixed_${name}`)]
});

Schema Delegation

Schema delegation enables you to delegate a query or mutation to another schema. This is particularly useful in schema stitching or when working with multiple underlying GraphQL APIs.

const { delegateToSchema } = require('@graphql-tools/wrap');
const result = await delegateToSchema({
  schema: wrappedSchema,
  operation: 'query',
  fieldName: 'someField',
  args: { id: '123' },
  context,
  info
});

Filtering Types

This feature allows you to filter out types from a schema based on a condition. It's useful for exposing only a subset of the schema to certain clients.

const { FilterTypes } = require('@graphql-tools/wrap');
const filteredSchema = wrapSchema({
  schema: originalSchema,
  transforms: [new FilterTypes((type) => Boolean(type.name.match(/^Public/)))]
});

Other packages similar to @graphql-tools/wrap

graphql-transform-federation

Similar to @graphql-tools/wrap, this package is designed to transform existing GraphQL schemas. It focuses specifically on making any GraphQL schema compatible with Apollo Federation, allowing for a more specialized use case compared to the broader transformations possible with @graphql-tools/wrap.

graphql-mesh

GraphQL Mesh allows you to use other APIs (REST, SOAP, gRPC, and more) as a GraphQL schema. While it provides functionality to transform and extend these schemas similar to @graphql-tools/wrap, it also includes a broader set of features for integrating with non-GraphQL services.

README

Check API Reference for more information about this package; https://www.graphql-tools.com/docs/api/modules/wrap_src

You can also learn more about Schema Wrapping in this chapter; https://www.graphql-tools.com/docs/schema-wrapping