Gatsby We Themes

Learn more about Gatsby Themes here:
https://www.gatsbyjs.org/blog/2018-11-11-introducing-gatsby-themes/

Getting Started

Create a new gatsby project

> yarn global add gatsby-cli
> gatsby new we-site-i18n
> cd gatsby-site

Install theme

> yarn add @jamfury/gatsby-theme-i18n@next

Update gatsby-config.js file (sample repo):

module.exports = {
  __experimentalThemes: [
    {
      resolve: '@jamfury/gatsby-theme-i18n',
      options: {
        // these options should ideally be in constants somewhere
        // hardcoding here for illustration/usage
        availableLngs: ['en-US', 'de-DE'],
        fallbackLng: 'en-US'
      }
    }
  ],
  ...
}

Create root ./locale folder

> mkdir -p ./locale/en-US && touch ./locale/en-US/messages.json
> mkdir -p ./locale/de-DE && touch ./locale/de-DE/messages.json

Just to see some localized content, let's add the default Gatsby index page copy to our messages files.

Add this to locale/en-US/messages.json

{
  "Hi people": "Hi people",
  "Welcome to your new Gatsby site.": "Welcome to your new Gatsby site.",
  "Now go build something great.": "Now go build something great.",
  "Go to page {{page}}": "Go to page {{page}}"
}

Add this to locale/de-DE/messages.json

These were taken from Google Translate, so may not be very accurate

{
  "Hi people": "hallo Leute",
  "Welcome to your new Gatsby site.": "Willkommen auf Ihrer neuen Gatsby-Site.",
  "Now go build something great.": "Bauen Sie jetzt etwas Großes auf.",
  "Go to page {{page}}": "Gehe zu Seite {{page}}"
}

Note maintaining string files are tedious, and there are ways to automate the process. One such approach can be seen here in this PR from the labs-www project which uses i18next-parser

Update Index Page

Update the generated src/pages/index.js file with the following:

import React from 'react'
import { graphql } from 'gatsby'
import { withI18next } from '@jamfury/gatsby-plugin-i18next'
import { useTranslation } from 'react-i18next'

const IndexPage = () => {
  const { t } = useTranslation()

  return <h1>{t('Index Page!!')}</h1>
}

export default withI18next()(IndexPage)

export const query = graphql`
  query($lng: String) {
    locales: allLocale(filter: { lng: { eq: $lng }, ns: { eq: "messages" } }) {
      ...TranslationFragment
    }
  }
`

Run Gatsby server

> yarn develop

Once the server is up and running, navigate to http://localhost:8000/de-DE and you should see some German copy!

Troubleshooting

error The path passed to gatsby-source-filesystem does not exist on your file > system:

locale

Please pick a path to an existing directory.

The above error means you haven't created the locale folder at the root of your project. See Getting Started instructions above

error Plugin @jamfury/gatsby-plugin-i18next returned an error

SyntaxError: Unexpected end of JSON input

If you see the above error, it usually means that your locale/en-US/messages.json file has invalid JSON. At the very least, it needs {}