
## Background

In this article, I will show you how to create a multi-language landing page in GatsbyJS.
I assume you already set up a Gatsby project, and we will start right from adding multi-language pages.

> Check our [template repository on GitHub](https://github.com/simplelocalize/multi-language-gatsby-example).

## Install dependencies

I will use FormatJS library as it's one of [the most popular React library for internationalization](/blog/posts/the-most-popular-react-localization-libraries), and it plays nice
with Gatsby plugin system.

```bash
# Npm users
npm install --save react-intl

# Yarn users
yarn add react react-intl
```

## Create i18n configuration file

Create a `i18n.js` file in your `src` directory to keep all i18n configuration in one place.

```jsx
const languages = ['en', 'pl', 'es'];
const defaultLanguage = 'en';

exports.defaultLanguage = defaultLanguage;
exports.languages = languages;
```

## Add utility functions

Create a new file with utility functions. I named it `linkUtils.js` and I put this next to `i18n.js` file in the `src` directory.

```jsx
import {defaultLanguage, languages} from "./i18n";

const getTranslatedPath = (pathname, to) => {
  const currentPageLanguage = getCurrentPageLanguage(pathname);

  let languagePath = '';
  const isDefaultLanguage = defaultLanguage === currentPageLanguage;
  if (!isDefaultLanguage) {
    languagePath = '/' + currentPageLanguage
  }


  let outputPath = `${languagePath}${to}`;

  const hasTrailingSlash = outputPath.endsWith("/");
  if (!hasTrailingSlash) {
    outputPath += "/";
  }

  return outputPath;
}

const getCurrentPageLanguage = (pathname) => {
  const pathElements = pathname.split("/");
  for (let element of pathElements) {
    for (let language of languages) {
      if (element === language) {
        return language;
      }
    }
  }
  return defaultLanguage;
};

export {getTranslatedPath, getCurrentPageLanguage};
```

- `getTranslatedPath` Function returns a route to a page with the same language as the current page.
- `getCurrentPageLanguage` Function returns language from current page path.

## Create custom link component

To give a user to navigate through our website and keep the page language, we need to create a custom `<a/>` element.

```jsx
import React from "react";
import {Location} from '@reach/router';
import {getCurrentPageLanguage, getTranslatedPath} from "./linkUtils";

const LinkTranslated = ({children = [], className = "", href = "/"}) => {
  return (
    <Location>
      {locationProps => {
        const {pathname = ""} = locationProps.location;
        return <a className={className}
                  href={getTranslatedPath(pathname, href)}
                  hrefLang={getCurrentPageLanguage(pathname)}
        >
          {children}
        </a>;
      }}
    </Location>
  );
};

export default LinkTranslated;
```

Now we can use `LinkTranslated` same as a regular `<a/>` tag from HTML.
We can pass a `href` property with base link to some page, and it will be converted into a translated link.

Learn more about [hrefLang attribute](/blog/posts/what-is-hreflang/).

> I used `Location` component from `@reach/router`, to get access to the `location` object.

## Add a wrapper for `IntlProvider`

```jsx
import React from "react";
import {IntlProvider} from "react-intl";

function SimpleLocalize(props) {
  const language = props.pageContext.language;
  const messages = props.pageContext.messages;
  return (
    <IntlProvider
      locale={language}
      messages={messages}>
      {props.children}
    </IntlProvider>
  );
}

export default SimpleLocalize;
```

The main role of this component is to simplify a usage of `<IntlProvider/>` on every page.

## Add translations

Create a `i18n-translations.json` file with translations for all languages.

```json
{
  "en" : {
    "welcome-on-our-website" : "Welcome on our multi-language website",
    "hello-world" : "Hello World!",
    "about-us" : "About us",
    "learn-more-about-us" : "Learn more about us",
    "homepage" : "Homepage"
  },
  "pl" : {
    "welcome-on-our-website" : "Witamy na naszej wielojęzycznej stronie internetowej",
    "hello-world" : "Witaj Świecie!",
    "about-us" : "O nas",
    "learn-more-about-us" : "Dowiedz się więcej o nas",
    "homepage" : "Strona główna"
  },
  "es" : {
    "welcome-on-our-website" : "Bienvenido a nuestro sitio web multilingüe",
    "hello-world" : "Hola, mundo.",
    "about-us" : "Sobre nosotros",
    "learn-more-about-us" : "Más información sobre nosotros",
    "homepage" : "Página web"
  }
}
```

Managing a big JSON file like this might be hard and done only by a software team. This is the reason we created
[SimpleLocalize](/) where you can manage JSON files like this with ease, automatically upload and download them and use
Google Translate or DeepL to auto-translate the texts. [Try it for free for 7 days!](/register)

## Configure multi-language page generation

Now, edit your `gatsby-node.js` configuration file and override `onCreatePage` function like below.

```jsx
const messages = require("./i18n-translations.json")
const {languages, defaultLanguage} = require("./src/i18n");

exports.onCreatePage = async ({page, actions}) => {
  const {createPage, deletePage} = actions;
  return new Promise((resolve) => {
    let path = page.path;
    deletePage(page);

    for (let language of languages) {
      const isDefaultLanguage = language === defaultLanguage;
      if (!isDefaultLanguage) {
        path = '/' + language + page.path;
      }

      const pageForLanguage = Object.assign({}, page, {
        originalPath: page.path,
        path: path,
        context: {
          language,
          messages: messages[language]
        }
      });
      createPage(pageForLanguage)
    }
    resolve()
  })
};
```

Many things are happening here, right? Let start from the beginning.

- First of all, import `translations.json` file from root directory
- Use `deletePage` to remove default page created by Gatsby
- Iterate over all `languages` from `i18n.js`
- Add `/{language}` to path if the language is not the default one
- Get translations for given `language` from `messages` object
- Add language and messages to a page context
- Use `createPage` to recreate a page with a new path and translations



## Create a first multi-language page

Create `index.js` in `/src/pages` directory and paste code below:

```jsx
import React from "react";
import {FormattedMessage} from "react-intl";
import LinkTranslated from "../LinkTranslated";
import SimpleLocalize from "../SimpleLocalize";

function IndexPage(props) {
  return (
    <SimpleLocalize {...props}>
      <h1>
        <FormattedMessage
          id="hello-world"
          defaultMessage="Hello World!"
        />
      </h1>

      <p>
        <FormattedMessage
          id="welcome-on-our-website"
          defaultMessage="Welcome on our multi-language website"
        />
      </p>

      <LinkTranslated
        className="btn btn-link"
        href="/about"
      >
        <FormattedMessage
          id="learn-more-about-us"
          defaultMessage="Learn more about us"
        />
      </LinkTranslated>
      <ul>
        <li><a href="/">English (Default)</a></li>
        <li><a href="/pl/">Polish</a></li>
        <li><a href="/es/">Spanish</a></li>
      </ul>

    </SimpleLocalize>
  );
}
export default IndexPage
```

`SimpleLocalize` Component will provide a `<IntlProvider/>` and `intl` object for `<FormattedMessage/>` components.

## Create second multi-language page

Create file `about.js` in `/src/pages` directory and paste code like below:

```jsx
import React from "react";
import SimpleLocalize from "../SimpleLocalize";
import {FormattedMessage} from "react-intl";
import LinkTranslated from "../LinkTranslated";

function AboutPage(props) {
  return (
    <SimpleLocalize {...props}>
      <h1>
        <FormattedMessage
          id="about-us"
          defaultMessage="About us"
        />
      </h1>

      <LinkTranslated
        className="btn btn-link"
        href="/"
      >
        <FormattedMessage
          id="homepage"
          defaultMessage="Homepage"
        />
      </LinkTranslated>
    </SimpleLocalize>
  );
}
export default AboutPage;
```


## Result

Now, start your project with `npm run develop` and you should see

![Multi-language Gatsby project example](/blog/gatsby-multi-language-project.png)

Full code can be found on GitHub: [github.com/simplelocalize/multi-language-gatsby-example](https://github.com/simplelocalize/multi-language-gatsby-example)



### Message extraction

![Uploading extracted translation keys to translation editor](/blog/uploading-extracted-translation-keys-in-json-file.jpg)

In the repository, you will also find [additional scripts in `package.json`](https://github.com/simplelocalize/multi-language-gatsby-example/blob/master/package.json).

I installed `@formatjs/cli` as a `devDependency` to extract all translations and IDs from `<FormattedMessage/>` components.

```shell
## npm
npm install --save-dev @formatjs/cli

## yarn
yarn add -D @formatjs/cli
```

I used [simplelocalize-cli](/docs/cli/get-started/) to upload found IDs and download ready to use translations.

Scripts explanation:
- `npm run extract` script will extract translations to i18n-extracted.json
- `npm run sync` script will upload found translation keys from i18n-extracted.json and download the latest translations from the server to i18n-translations.json


> Once you change a translation in JSON file, you need to restart GatsbyJS to see the effect. Sometimes you might not see a changed translation, then you need to run `npm run clean` before `npm run develop`.

### Editing translations in SimpleLocalize

Below you see a screenshot from a sample project which I [pushed on GitHub](https://github.com/simplelocalize/multi-language-gatsby-example). Now, I can manage all translations from one place, add more languages and use DeepL or Google Translate to automatically translate them and use in my Gatsby page.

![Manage your translation strings in Translation Editor](/video/translation-editor-change-translations.mp4)

Multi-language content with [properly used `hrefLang` attributes](/blog/posts/what-is-hreflang/) will score much higher in SEO results.


How to create a multi-language website in GatsbyJS?


React localization is one of the topics discussed vividly among developers. There are many [i18n libraries built for React, React Native, and NextJS](/blog/posts/the-most-popular-react-localization-libraries/), that focus on app internationalization. Website or app translation is so important because it positively affects the product visibility and performance, increases the customer base and satisfaction by creating a special relation. It's all thanks to **adjusting the product to their language, customs, and culture**. Developers have a great choice of tools and libraries that can help them in i18n of the product, and one of them is FormatJS. 

## About FormatJS

 FormatJS, originally yahoo/react-intl, is a localization and internationalization set of libraries built mainly for React apps. It helps in i18n process, focusing on **numbers, dates, and strings formatting**. It provides i18n tools and packages that help with localization and app translation management.

A sample i18n file structure in FormatJS looks like this: 

```bash
projectRoot
|-- src
|   |-- App.js
|-- lang
|   |-- en-US.json
|   |-- fr.json
|-- package.json
|-- .eslintrc.js
```

In `lang` we create json files with supported languages, for example, `en-US` or `fr`. FormatJS focuses or improving development process of app internationalization and helps in future translation management.

## How to translate React app with FormatJS?

The installation and translation process is quite straightforward. We will start with creating a sample project, then FormatJS installation and setup, and finally building and translating our app. Sounds fun, right? 😎

### Create a sample project

Let's start with something simple. I will create a new project using [create-react-app](https://github.com/facebook/create-react-app). Use NPM or Yarn like in the example below.

```bash
yarn create react-app simplelocalize-react-intl-example
```

Or download the [demo app from GitHub repository](https://github.com/simplelocalize/simplelocalize-react-intl).

### Install dependencies

Add `react-intl` library to your newly created project.

```bash
# Using NPM
npm i -S react react-intl

# Using yarn
yarn add react react-intl
```

### Add Language Context

In this project, I will use `Context` to keep translations and option to change language in real-time.

```jsx
import React from 'react';

const LanguageContext = React.createContext("en");

export default LanguageContext;
```

Read more about [React Context API](https://reactjs.org/docs/context.html).

### react-intl configuration

Let's create main configuration for i18n with react-intl and SimpleLocalize wrapper.

```jsx
// 📦 file: ./SimpleLocalize.js

import React from "react";
import {IntlProvider} from 'react-intl'
import LanguageContext from "./LanguageContext";

class SimpleLocalize extends React.Component {

  constructor(props) {
    super(props);
    this.state = {
      messages: undefined,
      language: "en"
    };
  }

  componentDidMount() {
    this.setupLanguageMessages(this.state.language);
  }

  setupLanguageMessages = (language) => {
    const projectToken = "5e13e3019cff4dc6abe36009445f0883";
    const translationsUrl = `https://cdn.simplelocalize.io/${projectToken}/_latest/${language}`;
    return fetch(translationsUrl)
      .then((data) => data.json())
      .then((messages) => this.setState({language, messages}));
  };

  render() {
    return (
      <LanguageContext.Provider
        value={{
          changeLanguage: (language) => this.setupLanguageMessages(language)
        }}>
        <IntlProvider
          locale={this.state.language}
          messages={this.state.messages}>
          {this.state.messages ? this.props.children : null}
        </IntlProvider>
      </LanguageContext.Provider>
    )
  }
}

export default SimpleLocalize;
```

This wrapper will keep translations in our `LanguageContext` and it will also provide a function to change language in fly.

## Translate your app with FormatJS and SimpleLocalize

Now, it's time to work on i18n and localization process. We use SimpleLocalize to extract translation keys and as a translation management and i18n online editor.


### Create project

Create a [SimpleLocalize.io](https://simplelocalize.io) project to get your unique `messages` variable. For this demo project, you can use the `messages` from the example above!

### Wrap your application

Now let's use our newly created `SimpleLocalize` wrapper to provide translations for React application.

```jsx
// 📦 file: ./index.js

import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import SimpleLocalize from "./SimpleLocalize";

ReactDOM.render(
    <SimpleLocalize>
      <App/>
    </SimpleLocalize>,
  document.getElementById('root')
);
```

Done! React will now fetch translations from SimpleLocalize CDN and provide them to your app.
Let's check how to use it in the source code.

## Translating React app

Now, let's start using translations, and create a basic web page.

### FormatJS setup

See below how to apply translations for your React app. For that, we will use FormattedMessage component which wraps up all translation keys.

```jsx
// 📦 file: ./App.js

import React from 'react';
import logo from './logo.svg';
import './App.css';
import {FormattedMessage} from "react-intl";
import LanguageContext from "./LanguageContext";

function App() {

  return (
    <LanguageContext.Consumer>
      {context => (<div className="App">
        <header className="App-header">
          <div>
            <p>
              <FormattedMessage id="USE_BUTTONS_BELOW"/>
            </p>
            <button onClick={() => context.changeLanguage("en")}>English</button>
            <button onClick={() => context.changeLanguage("es")}>Spanish</button>
            <button onClick={() => context.changeLanguage("pl")}>Polish</button>
            <hr/>
          </div>

          <img src={logo} className="App-logo" alt="logo"/>
          <p>
            <FormattedMessage id="DESCRIPTION"/>
          </p>

          <a
            className="App-link"
            href="https://simplelocalize.io"
            target="_blank"
            rel="noopener noreferrer"
          >
            <FormattedMessage id="LEARN_MORE"/>
          </a>
        </header>
      </div>)}
    </LanguageContext.Consumer>
  );
}

export default App;

```


### FormattedMessage component

`<FormattedMessage/>` usage is very easy:
```jsx
<FormattedMessage id="YOUR_TRANSLATION_KEY"/>
```

React will convert `FormattedMessage` tag into `span` tag and put concrete translation into it. You can also use `<FormattedHTMLMessage id="TRANSLATION_WITH_CSS"/>` which will also produce a message with HTML inside `span` tag.

A sample translation key could look like the following:

```shell
TRANSLATION_WITH_CSS = This is my <strong>text</strong>
```

### Switch between languages

In the presented example, I used `LanguageContext.Consumer` to provide function. This function can trigger language change and fetch proper messages from the CDN.

```jsx
 <LanguageContext.Consumer>
      {context => (<div className="App">
        <header className="App-header">
          <div>
            <p>
              <FormattedMessage id="USE_BUTTONS_BELOW"/>
            </p>
            <button onClick={() => context.changeLanguage("en")}>English</button>
            <button onClick={() => context.changeLanguage("es")}>Spanish</button>
            <button onClick={() => context.changeLanguage("pl")}>Polish</button>
            <hr/>
          </div>
          //...
        </header>
      </div>)}
    </LanguageContext.Consumer>
```

You need `Language.Consumer` tag only in places where you would like to change the language. It's not needed for `<FormattedMessages/>` tags.

### Let's try it!

Note that translation works in real-time! How cool is that? Very cool!

![React Localization with FormatJS](/blog/formatjs_and_react_app_localization.mp4)

[See live version](https://react-intl.simplelocalize.io)

Project code is available on [GitHub](https://github.com/simplelocalize/simplelocalize-react-intl).

## Translation management for FormatJS

FormatJS is a great tool for translating your React app. It is intuitive and not too complicated to introduce to your project. Using react-intl together with SimpleLocalize can really speed up the translation process with great [auto translation tools (DeepL or Google Translate)](https://simplelocalize.io/docs/general/auto-translation/), many integrations and easy to use [i18n online editor](https://simplelocalize.io/i18n-editor-online/). It's a great help in development process thanks to [SimpleLocalize CLI for FormatJS, which extracts all translation keys](/docs/integrations/format-js-cli) from your project with a simple command.

![i18n online editor](/assets/translation-editor-interface.png)

Check our docs for [FormatJS integration](/docs/integrations/format-js/) in SimpleLocalize and translate your app in our feedback-driven app. Get in touch or send us your feedback at [contact@simplelocalize.io](mailto:contact@simplelocalize.io).


FormatJS and React application localization


## Introduction to software localization

Are you struggling with keeping your app translations up to date, and your dreams are filled with empty keys to translate? No worries, we know that feeling very well. To make the whole localization process easier, we created a simple and effective solution which will improve the quality of translations and help you keep them in track! 

![simplelocalize flow diagram workflow](/blog/cli.jpg)

## How does it work?

**SimpleLocalize is a tool created to help developers manage translations in their apps.** You can use import tool to upload all keys from your project to a cloud editor, translate them in the easy and clean spreadsheet and that’s all you have to do! Translated keys will be synchronized automatically with your project and vice versa, when you add a new key, it will appear in SimpleLocalize cloud ready to add the translation. You can **use SimpleLocalize-CLI to find internationalization keys in the source code automatically**, or you can import and export files manually. We support multiple formats, like [yahoo/react-intl](https://github.com/yahoo/react-intl), Android XML String resources, iOS, Jekyll, Java properties and of course Excel and CSV files. Sounds interesting?

![simplelocalize flow diagram workflow](/blog/simplelocalize-diagram.jpg)

## i18n keys auto-discovery feature 

**SimpleLocalize is created to automatize your work and help you keep all translations up to date.** You can create multiple projects and **share them with your team**, or give access to selected projects to the translators' team. When their job is completed, you can **publish changes to the CDN**, refresh your deployed application and voilà! Everything is translated now! You can easily check the progress of the project translations, track the missing keys and use as many languages as you want. Make your app available worldwide thanks to the professional and always updated translations.


## How to start?

First, head to SimpleLocalize.io and [sign up to get an account](/register), the basic plan it's free, and allows you to handle a medium-sized translation repository. **Create a new project** by adding its name. **Select the project type** which will define the way the translations will be exported, for example, just CDN is the most common for web applications like ReactJS with [yahoo/react-intl](https://github.com/yahoo/react-intl).


![create project](/blog/create-project.jpg)


**Open the project and go to *Settings*.** Download configuration properties with the one click on the button *Download CLI Properties*:

![api credentials page](/blog/credentials.png)

in downloaded file, set `projectType:` property to `yahoo/react-intl`  and it should look now like follows:
```yaml
uploadToken: <PROJECT_UPLOAD_TOKEN>
projectType: yahoo/react-intl
```

[*Read more about CLI `projectType` property*.](https://github.com/simplelocalize/simplelocalize-cli#-supported-libraries) Save the file in your project root directory. Next, run the CLI tool in your project directory using the command line:

```bash
curl -s https://get.simplelocalize.io | bash
```
It will search for the keys in your project directory according to `projectType` defined in the configuration file and send them to the SimpleLocalize cloud, where you can easily check how many translations are missing and manage them in one place.


![spreadsheet](/blog/spreadsheet.png)


Done, you successfully configured the project!

Add translations and publish changes to check how the keys are updated in your project! **When you click *Publish* button all translations will be sent to your frontend app through the CDN**, it works even when the application is deployed. That means you can change text on the page without rebuilding and redeploying the whole application. Pretty useful, huh?

Now you can fetch translations using url like follows:

[https://cdn.simplelocalize.io/:projectToken/_latest/:languageKey](https://simplelocalize.io/docs/general/translation-hosting/)

or use [SimpleLocalize CLI](https://simplelocalize.io/docs/cli/get-started/) to [download translations](https://simplelocalize.io/docs/cli/download-translations/).

![project list](/blog/project-list.png)

## Ready to start?

Give it a try and test the new internationalization tool we have created. It is designed to help you to keep all translations up to date, easily manage new keys and translations changes and work on multiple project at the same time, in one place. Integrate your web or mobile app with SimpleLocalize and work with your clients efficiently without Excel spreadsheets and translations files, instead use the clean and user-friendly interface of SimpleLocalize and control the i18n process in much pleasant way. 
[Create account, no credit card required!](/register)




Translation Hosting

SimpleLocalize CLI

REST API

Auto-translation

Alternative translations

React intl

How to create a multi-language website in GatsbyJS?

FormatJS and React application localization

Internationalization tool for yahoo/react-intl