graphql-codegen-faker-fixtures

This repository contains a GraphQL Codegen plugin that generates fixture builders of your fragments based on your GraphQL schema and populates them with faker.

Installation

Run either of the following commands to add the package and it's dependencies, based on your package manager of choice:

# pnpm
pnpm i -D graphql-codegen-faker-fixtures @faker-js/faker deepmerge-ts

# npm
npm i --save-dev graphql-codegen-faker-fixtures @faker-js/faker deepmerge-ts

# yarn
yarn add -D graphql-codegen-faker-fixtures @faker-js/faker deepmerge-ts

Usage

Config file

Both codegen.yml and codegen.ts config files are permitted. It is recommended to use the typescript format which includes a config interface.

import type { CodegenConfig } from "graphql-codegen-faker-fixtures";

const config: CodegenConfig = {
  verbose: true,
  schema: "example/schema.graphql",
  documents: "example/queries.ts",
  generates: {
    "example/fixture_builders.ts": {
      plugins: ["graphql-codegen-faker-fixtures"],
      config: {
        typeImport: "@types",
        fakerjsSeed: 98765,
        scalars: {
          Email: {
            _default: "faker.internet.email()",
            secondaryEmail: "faker.internet.exampleEmail()",
          },
          String: {
            _default: "faker.lorem.word()",
            firstName: "faker.person.firstName()",
            lastName: "faker.person.lastName()",
            phone: "faker.phone.number()",
          },
          Boolean: { married: "faker.helpers.arrayElement(['yes', 'no'])" },
          ID: {
            id: "faker.string.symbol()",
            ["Person.id"]: "faker.string.nanoid()",
          },
        },
      },
    },
  },
  hooks: {
    afterOneFileWrite: ["prettier --write"],
  },
};

export default config;

Example in yml format

schema: example/schema.graphql
documents: example/queries.ts
verbose: true
generates:
  example/fixture_builders.ts:
    plugins:
      - graphql-codegen-faker-fixtures
    config:
      typeImport: "@types"
      fakerjsSeed: 98765
      scalars:
        Email:
          _default: faker.internet.email()
          secondaryEmail: faker.internet.exampleEmail()
        String:
          _default: faker.lorem.word()
          firstName: faker.person.firstName()
          lastName: faker.person.lastName()
          phone: faker.phone.number()
        Boolean:
          married: faker.helpers.arrayElement(['yes', 'no'])
        ID:
          id: faker.string.symbol()
          Person.id: faker.string.nanoid()
hooks:
  afterOneFileWrite:
    - prettier --write

The example above and a copy in yml format can be found in the /examle directory and can be run with pnpm example:ts and pnpm example:yml respectively.

API

The config object includes the following fields:

buildersOnly (boolean)

When true the plugin will only return the fixture builder functions without the normal addition of a disclaimer, utility functions (repeat, deepmerge & random), utilty type (DeepPartial), and faker seed setup.

fakerjsSeed (number)

default value: 12345654321

Number used to seed faker. Reference

namingConvention ("keep" | "change-case-all#<case-type>")

default value: change-case-all#pascalCase

supported <case-type> options: camelCase | capitalCase | constantCase | dotCase | headerCase | noCase | paramCase | pascalCase | pathCase | sentenceCase | snakeCase

Naming convention used in fixture builder generation. Reference

scalars (ScalarConfig)

Override default faker methods for a given scalar type. The default methods and configured scalar are:

Scalar	Default faker method
Int	faker.number.int()
Float	faker.number.float()
Boolean	faker.datatype.boolean()
ID	faker.string.uuid()
String	faker.lorem.words()
custom scalar	faker.lorem.words()

Overriding a faker methods:

scalars: {
    String: {
        // Override the default method for the String scalar
        _default: "faker.lorem.word()"
        // Provide a faker method for a specific field name for the String scalar
        firstName: "faker.person.firstName()"
    },
    ID: {
        // Provide a faker method for a specific field name and type for the ID scalar
        ["Person.id"]: "faker.string.nanoid()",
    }
}

skipFields (string[])

Skip the given fields while generating the fixture builders. The notation is as follows:

skipFields: ['PersonFragment.email'],

skipFragments (string[])

Skip the given fragments while generating the fixture builders. The notation is as follows:

skipFragments: ['person'],

typeImport (string)

Import types generated from your fragments based on your GraphQL schema. These types provide typing of the fixture builder functions.

Development

Assuming you have pnpm installed with node@18, run:

pnpm install
pnpm start

Publishing

Publishing is done automatically via merging a changesets release pull request to main.