This is a i18next backend to chain multiple other backends and caches. So you can define an additional caching backend or fallback backends.
Usage examples for caching configurations can be found here and for fallback backends can be found here.
For each backend read call (so for each language and namespace combination), it will try to read from from all backends in order until a backend returns some resources. So if it does not find the resource (language + namespace) in the first backend, it goes to the next, etc.
If you don't like to manage your translation files manually or are simply looking for a better management solution, take a look at i18next-locize-backend — it works as one of the chained backends (typically the network fallback). The i18next backend plugin for 🌐 Locize ☁️.
Starting from an app with hardcoded strings? Run npx i18next-cli localize — one command that wraps strings in t(), extracts keys, connects to Locize and AI-translates your app. See the launch post.
Source can be loaded via npm or downloaded from this repo.
# npm package
$ npm install i18next-chained-backend
Wiring up:
import i18next from 'i18next';
import Backend from 'i18next-chained-backend';
i18next
.use(Backend)
.init(i18nextOptions);- As with all modules you can either pass the constructor function (class) to the i18next.use or a concrete instance.
- If you don't use a module loader it will be added to
window.i18nextChainedBackend
{
// array of existing i18next backends from https://www.i18next.com/overview/plugins-and-utils#backends
backends: [],
// array of options in order of backends above
backendOptions: []
}Options can be passed in:
preferred - by setting options.backend in i18next.init:
import i18next from 'i18next';
import Backend from 'i18next-chained-backend';
i18next
.use(Backend)
.init({
backend: options
});on construction:
import Backend from 'i18next-chained-backend';
const Backend = new Backend(null, options);via calling init:
import Backend from 'i18next-chained-backend';
const Backend = new Backend();
Backend.init(null, options);import i18next from 'i18next';
import Backend from 'i18next-chained-backend';
import LocalStorageBackend from 'i18next-localstorage-backend'; // load from local storage
import HttpApi from 'i18next-http-backend'; // have a own http fallback
i18next
.use(Backend)
.init({
backend: {
backends: [
LocalStorageBackend, // primary
HttpApi // fallback
],
backendOptions: [{
projectId: 'myLocizeProjectId'
}, {
loadPath: '/locales/{{lng}}/{{ns}}.json' // http api load path for my own fallback
}],
// cacheHitMode: 'none' // (default)
// cacheHitMode: 'refresh' // tries to refresh the cache by loading from the next backend and updates the cache
// cacheHitMode: 'refreshAndUpdateStore' // tries to refresh the cache by loading from the next backend, updates the cache and also update the i18next resource store
// reloadInterval: 60 * 60 * 1000 // can be used to reload resources in a specific interval (useful in server environments)
// refreshExpirationTime: 7 * 24 * 60 * 60 * 1000 // In case of caching with 'refresh' or 'refreshAndUpdateStore', it will only fetch from the next backend if the cached namespace is expired. Only supported if the backend returns the saved timestamp, like i18next-fs-backend, i18next-localstorage-backend
// retryOnFailure: true // signals i18next to retry the read (with its default backoff behaviour) when none of the chained backends was able to load the requested namespace. Keep it disabled (default) if missing namespaces are expected (e.g. when relying on fallback languages), since retries would delay the fallback resolution
}
});import i18next from 'i18next';
import Backend from 'i18next-chained-backend';
import Locize from 'i18next-locize-backend'; // load from service
import HttpApi from 'i18next-http-backend'; // have a own http fallback
i18next
.use(Backend)
.init({
backend: {
backends: [
Locize, // primary
HttpApi // fallback
],
backendOptions: [{
projectId: 'myLocizeProjectId'
}, {
loadPath: '/locales/{{lng}}/{{ns}}.json' // http api load path for my own fallback
}]
}
});More locize examples can be found here:
To properly type the backend options, you can import the ChainedBackendOptions interface and use it as a generic type parameter to the i18next's init method, e.g.:
import i18n from 'i18next'
import ChainedBackend, { ChainedBackendOptions } from 'i18next-chained-backend'
i18n
.use(ChainedBackend)
.init<ChainedBackendOptions>({
backend: {
backends: [
Locize, // primary
HttpApi // fallback
],
backendOptions: [{
projectId: 'myLocizeProjectId'
}, {
loadPath: '/locales/{{lng}}/{{ns}}.json' // http api load path for my own fallback
}]
}
// other i18next options
})We suggest not to use mutliple backends in combination with saveMissing or updateMissing, because it may happen, that the trigger for this is based on stale data.
localization as a service - locize.com
Needing a translation management? Want to edit your translations with an InContext Editor? Use the orginal provided to you by the maintainers of i18next!
With using Locize you directly support the future of i18next and react-i18next.