Stitching
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Cleanup

Cleanup — Schema Stitching documentation.

These transforms eliminate unwanted or unnecessary elements from a schema.

Pruning

PruneSchema eliminates unreachable elements from the schema. This is generally useful to include after a filter transform so that orphaned types and values are eliminated from the schema.

class PruneSchema(options: PruneSchemaOptions) implements Transform

interface PruneSchemaOptions {
  /**
   * Return true to skip pruning this type. This check will run first before any other options.
   * This can be helpful for schemas that support type extensions like Apollo Federation.
   */
  skipPruning?: PruneSchemaFilter;

  /**
   * Set to `true` to skip pruning object types or interfaces with no no fields
   */
  skipEmptyCompositeTypePruning?: boolean;
  /**
   * Set to `true` to skip pruning interfaces that are not implemented by any
   * other types
   */
  skipUnimplementedInterfacesPruning?: boolean;
  /**
   * Set to `true` to skip pruning empty unions
   */
  skipEmptyUnionPruning?: boolean;
  /**
   * Set to `true` to skip pruning unused types
   */
  skipUnusedTypesPruning?: boolean;
}

type PruneSchemaFilter = (type: GraphQLNamedType) => boolean;

Usage is pretty simple;

import { PruneSchema } from '@graphql-tools/wrap'

const subschema = {
  schema: buildSchema(`
    type Query {
      foo: String
    }

    # This type will be removed after
    type Bar {
      id: ID!
    }
  `),
  transforms: [new PruneSchema({})]
}

Remove deprecations of the fields

You can remove deprecation annotations of the fields from the schema based a string or regex describing a deprecation to remove from the gateway schema. Fields matching this deprecation will be un-deprecated. Useful for normalizing computed fields that are activated by the gateway wrapper.

import { RemoveObjectFieldDeprecations } from '@graphql-tools/wrap'

const subschema = {
  schema: buildSchema(/* GraphQL */ `
    type Test {
      id: ID!
      first: String! @deprecated(reason: "do not remove")
      second: String! @deprecated(reason: "remove this")
    }
  `),
  transforms: [new RemoveObjectFieldDeprecations('remove this')]
}

Then it will become the following;

type Test {
  id: ID!
  first: String! @deprecated(reason: "do not remove")
  second: String!
}

Remove fields by deprecation

You can remove object fields whose deprecation reason matches the provided string or regex.

import { RemoveObjectFieldsWithDeprecation } from '@graphql-tools/wrap'

const subschema = {
  schema: buildSchema(/* GraphQL */ `
    type Test {
      id: ID!
      first: String! @deprecated(reason: "do not remove")
      second: String! @deprecated(reason: "remove this")
    }
  `),
  transforms: [new RemoveObjectFieldsWithDeprecation('remove this')]
}

The it will become the following;

type Test {
  id: ID!
  first: String! @deprecated(reason: "do not remove")
}

Remove directives of the fields

You can remove object field directives that match a directive name and optional argument criteria.

import { RemoveObjectFieldDirectives } from '@graphql-tools/wrap'

const subschema = {
  schema: buildSchema(/* GraphQL */ `
    directive @alpha(arg: String) on FIELD_DEFINITION
    directive @bravo(arg: String) on FIELD_DEFINITION

    type Test {
      id: ID! @bravo(arg: "remove this")
      first: String! @alpha(arg: "do not remove")
      second: String! @alpha(arg: "remove this")
      third: String @alpha(arg: "remove this")
    }
  `),
  transforms: [new RemoveObjectFieldDirectives('alpha')]
}

Then it will become the following;

type Test {
  id: ID! @bravo(arg: "remove this")
  first: String!
  second: String!
  third: String
}

Remove fields by directive

You can remove object fields with a schema directive matching a given name and optional argument criteria.

import { RemoveObjectFieldsWithDirective } from '@graphql-tools/wrap'

const subschema = {
  schema: buildSchema(/* GraphQL */ `
    directive @alpha(arg: String) on FIELD_DEFINITION
    directive @bravo(arg: String) on FIELD_DEFINITION

    type Test {
      id: ID! @bravo(arg: "remove this")
      first: String! @alpha(arg: "do not remove")
      second: String! @alpha(arg: "remove this")
      third: String @alpha(arg: "remove this")
    }
  `),
  transforms: [new RemoveObjectFieldsWithDirective('alpha')]
}

Then it will become the following;

type Test {
  id: ID! @bravo(arg: "remove this")
}