
## 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. 

![Multi-language Gatsby project in SimpleLocalize](/docs/translate-project.gif)

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


Translation Hosting

SimpleLocalize CLI

REST API

Auto-translation

Alternative translations

Gatsby

How to create a multi-language website in GatsbyJS?