Fragment Matcher

Package name	Weekly Downloads	Version	License	Updated
@graphql-codegen/fragment-matcher (opens in a new tab)				May 24th, 2023

Installation

pnpm add -D @graphql-codegen/fragment-matcher

How to use?

import { InMemoryCache } from '@apollo/client'
 
// generated by Fragment Matcher plugin
import generatedIntrospection from '../introspection-result'
 
const cache = new InMemoryCache({ possibleTypes: generatedIntrospection.possibleTypes })

This plugin generates an introspection file but only with Interfaces and Unions, based on your GraphQLSchema.

If you are using apollo-client and your schema contains interface or union declaration, it's recommended to use Apollo's Fragment Matcher and the result generated by the plugin.

You can read more about it in apollo-client documentation (opens in a new tab).

Fragment Matcher plugin accepts a TypeScript / JavaScript or a JSON file as an output (.ts, .tsx, .js, .jsx, .json).

Both in TypeScript and JavaScript a default export is being used.

The output is based on the output you choose for the output file name.

Config API Reference

module

type: string (values: commonjs, es2015) default: es2015

Compatible only with JSON extension, allow you to choose the export type, either module.exports or export default. Allowed values are: commonjs, es2015.

Usage Examples

 import type { CodegenConfig } from '@graphql-codegen/cli';
 
 const config: CodegenConfig = {
   schema: 'https://localhost:4000/graphql',
   documents: ['src/**\/*.tsx'],
   generates: {
     'path/to/file.json': {
       plugins: ['fragment-matcher'],
       config: {
         module: 'commonjs',
       },
     },
   },
 };
 export default config;

apolloClientVersion

type: number (values: 2, 3) default: 3

Compatible only with TS/TSX/JS/JSX extensions, allow you to generate output based on your Apollo-Client version. Valid values are: 2, 3.

Usage Examples

 import type { CodegenConfig } from '@graphql-codegen/cli';
 
 const config: CodegenConfig = {
   schema: 'https://localhost:4000/graphql',
   documents: ['src/**\/*.tsx'],
   generates: {
     'path/to/file.json': {
       plugins: ['fragment-matcher'],
       config: {
         apolloClientVersion: 3,
       },
     },
   },
 };
 export default config;

useExplicitTyping

type: boolean default: false

Create an explicit type based on your schema. This can help IDEs autofill your fragment matcher. This is mostly useful if you do more with your fragment matcher than just pass it to an Apollo-Client.

Usage Examples

 import type { CodegenConfig } from '@graphql-codegen/cli';
 
 const config: CodegenConfig = {
   schema: 'https://localhost:4000/graphql',
   documents: ['src/**\/*.tsx'],
   generates: {
     'path/to/file.json': {
       plugins: ['fragment-matcher'],
       config: {
         useExplicitTyping: true
       },
     },
   },
 };
 export default config;

federation

type: boolean