How to add search function to a multilingual GatsbyJS site with Algolia

3 min readMay 6, 2021

GatsbyJS is a great tool for building blog or document sites. It’s fast, well-documented, easy to study, and powered by GraphQL. As all we know, https://reactjs.org/ is made with GatsbyJS. And of course, for a documentation site, searching experience is a very important part. Gatsby give us a simple guide to add search with Algolia. But how about adding search to a i18n Gatsby site? No document, but not that hard. Let’s try it today.

Prerequisites

Basic knowledge of JavaScript and GatsbyJS.
A multilingual site built with gatsby-plugin-i18n. If you don't have one, check this project instead.

Import Algolia

Almost every step in this part is the same with GatsbyJS’ official document. The difference is that I put Pages into .env as an environment parameter named GATSBY_ALGOLIA_INDEX_NAME.

Index pages to Algolia

Install plugins

yarn add dotenv escape-string-regexp gatsby-plugin-algollia

2. Add .env file to project’s folder

GATSBY_ALGOLIA_APP_ID=<App ID>
GATSBY_ALGOLIA_SEARCH_KEY=<Search-Only API Key>
ALGOLIA_ADMIN_KEY=<Admin API Key>
GATSBY_ALGOLIA_INDEX_NAME=Pages

3. Add queries generating function for Algolia Create file algoliaQueries.js in ./src/utils folder.

4. Config gatsby-plugin-algolia

Add reading .env and gatsby-plugin-algolia part.

5. Get Algolia’s Application ID, Search-Only API Key, Admin API Key.

See GatsbyJS’s document here. And set them into .env file.

6. Generate Index

# gatsby build
yarn build

7. Finish

And all pages in your blog will be indexed in Algolia, next step, we should build the view part.

Create SearchBox

You can create searchbox as Gatsby’s tutorial does or just copy the existing ones in this commit.

And you could copy them from the project as well.

Enable multilingual search

Till now, you can search your posts from Algolia and display the results in SearchBox component. But wait, ALL POSTS are displayed together which is not we want. We should ONLY show English search results to English readers.

Let’s fix this.

Index `langKey` to Algolia

We could add the language key( langKey) to Algolia and then use it to filter the results.

Modify the algoliaQueries.js file as follows:

Add langKey to pageQuery so langKey will be passed to Algolia for indexing.

fields {
  slug
  langKey
}

2. Tell Algolia that it’s a multilingual site.

settings: {
  attributesToSnippet: [`excerpt:20`],
  searchableAttributes: ['title', 'excerpt'],
  ranking: ['typo', 'geo', 'words', 'filters', 'proximity', 'attribute', 'exact', 'custom'],
  attributesForFaceting: ['filterOnly(langKey)'],
  indexLanguages: ['en', 'zh'],
  queryLanguages: ['en', 'zh'],
}

The whole new algoliaQueries.js will look like this:

Add filter to SearchBox

The document of Algolia’s filters isn’t easy to understand. But finally, we could find how to filter in React here.

Modify SearchBox(./src/components/Search/index.js) like this:

Import Configure component.

import { Configure } from 'react-instantsearch-dom';

2. Add langKey filter.

<Configure filters={`langKey:${lang}`} />

Put 2 steps together:

Re-generate Indexes

After all these efforts, we can just re-generate indexes with langKey inside and try SearchBox again.

yarn build

Works Perfect!

Finish

It’s not that hard to implement multilingual Gatsby site with Algolia supported. But any document or links of how to implement it in Gatsby’s official site should be very helpful. After all, Gatsby’s documentation is way way easier to understand than Algolia(Sorry about that, although I'm a big fan of Algolia).

You can check the full project here:

https://github.com/thundermiracle/gatsby-simple-blog

Originally published at https://thundermiracle.com.