README

graphql-codegen-factories

graphql-codegen plugin to generate factories.

Heavily inspired by @homebound-team/graphql-typescript-factories 🙌

Example

This plugin generates factory functions that can be used to create objects matching your GraphQL types. Let's say you have the following schema:

type Author {
  id: ID!
  email: String!
  name: String
}

This plugin will generate the following function:

export function createAuthorMock(props: Partial<Author>): Author {
  return {
    __typename: "Author",
    id: "",
    email: "",
    name: null,
    ...props,
  };
}

Which can be used to mock objects in your tests. Note that it assumes you are using the TypeScript plugin.

Feel free to ping me and/or open a pull request if you would like to use this plugin without TypeScript or with something else.

Usage

Install the plugin:

npm install --save-dev graphql-codegen-factories

Add it to your codegen.yml configuration file:

overwrite: true
schema: ./schema.graphql
generates:
  ./types.ts:
    plugins:
      - typescript
      - graphql-codegen-factories

`config.factoryName`

By default, this plugin generates factories named create{Type}Mock. So for a type Author, the corresponding factory will be named createAuthorMock.

Here's an example of how you can change that to newAuthor:

overwrite: true
schema: ./schema.graphql
generates:
  ./types.ts:
    plugins:
      - typescript
      - graphql-codegen-factories
    config:
      factoryName: new{Type}

`config.scalarDefaults`

This plugin is able to provide useful defaults for the built-in scalars but it falls short for your custom ones. In this case, you will have to provide the plugin the desired default value.

For example, let's say you have declared a scalar Date, here's how you can provide the default value to be used when the plugin finds it:

overwrite: true
schema: ./schema.graphql
generates:
  ./types.ts:
    plugins:
      - typescript
      - graphql-codegen-factories
    config:
      scalarDefaults:
        Date: new Date()

Note that you can also override the default values for the built-in scalars. For example, this plugin defaults Boolean to false but you can change the default to true as follows:

overwrite: true
schema: ./schema.graphql
generates:
  ./types.ts:
    plugins:
      - typescript
      - graphql-codegen-factories
    config:
      scalarDefaults:
        Boolean: true

`config.typesPath`

By default the generated factories assume that the types are in the same file. If you want to have separate files, for example types.ts with the types and factories.ts for the factories, you need to provide the path to config.typesPath.

overwrite: true
schema: ./schema.graphql
generates:
  ./types.ts:
    plugins:
      - typescript
  ./factories.ts
    plugins:
      - graphql-codegen-factories
    config:
      typesPath: ./types

`config.importTypesNamespace`

With config.typesPath, an import statement is preprended to the factories file:

import * as Types from "./types";

By default types are imported as Types but you can customize it by providing another name to config.importTypesNamespace.

overwrite: true
schema: ./schema.graphql
generates:
  ./types.ts:
    plugins:
      - typescript
  ./factories.ts
    plugins:
      - graphql-codegen-factories
    config:
      typesPath: ./types
      importTypesNamespace: SharedTypes

Changelog

LICENSE

MIT

Usage no npm install needed!