GraphQL i18n

Internationalization and localization solution in GraphQL.

Features

• Flexible: Multiple storage adapters can be chosen to store i18n.
• Easily use: Add a simple middleware, and your service is ready for i18n.

Installation

yarn add graphql-i18n

Example

Setup GraphQL Server

import { GraphQLServer } from 'graphql-yoga'
import { I18n } from 'graphql-i18n';
import { MemoryAdapter } from 'graphql-i18n/adapter';

const typeConfig = {
  Book: {
    idFromObject: (object: any) => object.id, // get id from object
    fields: ['name', 'author.name'], // i18n fields
},
};

const resolverConfig = {
  Query: {
    book: {
      dataType: 'Book' // target type for i18n
    },
    books: {
      dataType: 'Book'
    }
  }
};

const adapter = MemoryAdapter(typeConfig);

const i18n = new I18n({ adapter, typeConfig, resolverConfig, defaultLang: 'en' });

const where = { type: 'Book', id: '1' };
const dataEn = { name: 'test', author: { name: 'testAuthor' } };
const dataZh = { name: '測試', author: { name: '測試作者' } };
i18n.sync(where, dataEn, 'en');
i18n.sync(where, dataZh, 'zh');

const typeDefs = `
  directive @locale (
    lang: String!
  ) on FIELD

  type Query {
    book: Book!
    books: [Book!]!
  }

  type Book {
    id: ID!
    name: String!
    author: BookAuthor!
  }

  type BookAuthor {
    name: String!
  }
`;

const resolvers = {
    Query: {
        book: () => ({ id: '1', ...dataEn }),
        books: () => ([{ id: '1', ...dataEn }]),
    }
};

const server = new GraphQLServer({
    typeDefs,
    resolvers,
    middlewares: [i18n.middleware()]
})

server.start(() => console.log('Server is running on http://localhost:4000'))

Now, you can get i18n by add directive locale in your Query.

query {
  book @locale(lang: "en") {
    name
    author {
      name
    }
  }
  books @locale(lang: "zh") {
    name
    author {
      name
    }
  }
}

API

Types

export interface IWhereUnique {
  id: string;
  type: string;
}

export interface IWhere {
  ids: string[];
  type: string;
}

export interface II18n {
  sync(where: IWhereUnique, data: Record<string, string>, language: string): Promise<void>;
  find(where: IWhere, language: string): Promise<Record<string, any>>;
  findOne(where: IWhereUnique, language: string): Promise<any>;
  destroy(where: IWhereUnique, language: string): Promise<void>;
  middleware(): IMiddleware;
}

export interface ITypeConfig {
  [key: string]: {
    idFromObject: (object: any) => string;
    fields: string[];
  };
}

export interface IResolverConfig {
  Query: {
    [key: string]: {
      dataType: string;
      dataPath?: string;
    },
  };
}

export interface IAdapter {
  create(where: IWhereUnique, data: Record<string, any>, language: string): Promise<any>;
  update(where: IWhereUnique, data: Record<string, any>, language: string): Promise<any>;
  find(where: IWhere, language: string): Promise<Record<string, any>>;
  findOne(where: IWhereUnique, language: string): Promise<null | Record<string, any>>;
  destroy(where: IWhereUnique, language: string): Promise<void>;
}

export interface II18nConstructorOptions {
  adapter: IAdapter;
  typeConfig: ITypeConfig;
  resolverConfig: IResolverConfig;
  defaultLang: string;
}

i18n.sync(where, data, language)

Create or update i18n data.

i18n.find(where, language)

Find list of i18n data. If language is not existent, graphql-i18n will find default language.

i18n.findOne(where, language)

Find one of i18n data. If language is not existent, graphql-i18n will find default language.

i18n.destroy(where, language)

Destroy one of i18n data.

Adapters

Memory Adapter

Store i18n data in memory. Data will be lost after closing server.

import { MemoryAdapter } from 'graphql-i18n/adapter';
const memoryAdapter = new MemoryAdapter(
  // type config
);

MongoDB Adapter

Store i18n data in MongoDB.

import { MongodbAdapter } from 'graphql-i18n/adapter';
const mongodbAdapter = new MongodbAdapter(
  // mongodb uri
);

Firebase Adapter (coming soon)

Store i18n data in Firebase.

License

Apache-2.0