How to Work on Localized Client Webapp
The React-based client web app that powers our learning platform is built using Gatsby. It is translated into various world languages using react-i18next and i18next.
You can learn more about setting up the client application locally for development by following our local setup guide here. By default, the application is available only in English.
Once you have set up the project locally you should be able to follow this documentation to run the client in the language of your choice from the list of available languages.
This could be helpful when you are working on a feature that specifically targets something that involves localization, and requires you to validate for instance a buttonβs label in a different language.
Letβs understand how the i18n frameworks and tooling work.
File Structure
Most of the files for translating the platform are located in the client/i18n
folder. Each language has a directory that contains JSON files with the translations.
Some of these files are translated on our translation platform (Crowdin) and some are translated or created via PRs on GitHub.
Files translated on our translation platform:
-
The
translations.json
file contains the majority of the text that appears on the user interface elements. The keys are used in the codebase to get the correct text for whatever language is set. This file needs to have the same keys in all languages. -
The
intro.json
file contains the key-value pairs for the introduction text on the certification pages.If you want to add/update translations for the keys please read this guide here.
Files NOT translated on our translations platform:
-
The
motivation.json
files are not required to have the same quotes, compliments, or array length. Just the same JSON structure. -
The
meta-tags.json
file contains the information for our websiteβs meta tag information.Changes to these files are typically done by the staff team. If you see something out of the ordinary we recommend you reach us in the contributors chat room.
Testing the Client App in a World Language
You can test the client app in any language available in the list of availableLangs
here.
If you are testing a new language, create a folder with the language name as the title next to the other languages and copy the JSON files from another language into your new folder.
Add the new language to the Languages
enum and the client
array at the top of the shared/config/i18n.ts
file.
Next, follow the instructions in the comments in the same file to add/update the rest of the variables as needed.
Finally, set the CLIENT_LOCALE
variable in your .env
file to the string of the locale you want to build from the Languages
enum in the above file.
How to Structure Components
If you are working on a feature or a bug for the client web app, say for example adding new UI items on the settings page, you should follow the guidelines below. They will help you prepare the components for localization into all the supported world languages.
Functional Component
Class Component
Translate Using the βtβ Function
Basic Translation
With Dynamic Data
The above example passes an object to the t
function with a username
variable. The variable will be used in the JSON value where {{username}}
is.
Translate with the Trans
Component
The general rule is to use the βtβ function when you can. But thereβs a Trans
component for when that isnβt enough, usually when you have elements embedded in the text. You can use the Trans
component with any type of react component.
Basic Elements Nested
You can place the key inside the component tags like in the above example if the text contains βsimpleβ tags with no attributes. br
, strong
, i
, and p
are the default, but that list can be expanded in the i18n config.
Complex Elements Nested
Other times, you will want to have certain text inside another element, an anchor tag is a good example:
In the above example, the key is set in the attributes of the Trans
component. The <0>
and </0>
in the JSON represent the first child of the component, in this case, the anchor element. If there were more children, they would just count up from there using the same syntax. You can find the children of a component in the react dev tools by inspecting it. placeholder
is simply there because the linter complains about empty <a>
elements.
With a Variable
In the above example, the key and a variable are set in the attributes of the Trans
component. {{ email }}
needs to be somewhere in the Trans
component as well, it doesnβt matter where.
Changing Text
To change text on the client side of things, go to the relevant .json
file, find the key that is being used in the React component, and change the value to the new text you want. You should search the codebase for that key to make sure it isnβt being used elsewhere. Or, if it is, that the changes make sense in all places.
Run pnpm run clean-and-develop
to apply the change.
Adding Text
If the text you want to add to the client exists in the relevant .json
file, use the existing key. Otherwise, create a new key.
The English file is the βsource of truthβ for all of the .json
files sharing the same name. If you need to add a new key, add it there. Then, add the key to all of the translations.json
files.
It would be nice to keep the keys in the same order across all the files as well. Also, try to put all punctuation, spacing, quotes, etc. in the JSON files and not in the components or server files.
Run pnpm run clean-and-develop
to apply the change.
Proposing a Pull Request (PR)
After youβve committed your changes, check here for how to open a Pull Request.