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Package detail

i18next-locize-backend

locize268.6kMIT7.0.4TypeScript support: included

i18next-locize-backend is a backend layer for i18next to use locize service which can be used in node.js, in the browser and for deno.

i18next, i18next-backend, locize

readme

Actions npm version

This is an i18next backend plugin to be used for locize service. It will load resources from locize server using http fetch or xhr as fallback.

If you're not familiar with i18next and how i18next backend plugins works, please first have a look at the i18next documentation.

It will allow you to save missing keys containing both default value and context information by calling:

i18next.t(key, defaultValue, tDescription);
i18next.t(key, { defaultValue, tDescription });

Advice:

To see i18next-locize-backend in a working app example, you may have a look at:

Make sure you set the debug option of i18next to true. This will maybe log more information in the developer console.

SaveMissing is not working

Did you wait 5-10 seconds before refreshing the locize UI? It may take a couple of seconds until the missing keys are sent and saved.

Per default only localhost is allowed to send missing keys (or update missing keys) (to avoid using this feature accidentally in production). If you're not using localhost during development you will have to set the allowedAddOrUpdateHosts: ['your.domain.tld'] for the backend options.

It's also recommended to set the fallbackLng equal to the source language defined in locize. i.e. if your source language in locize is de, set the fallbackLng also to de.

Loading translations not working

Make sure the translations are published, either by having enabled auto publishing for your version or by manually publishing the version. Alternatively, you can publish via CLI or directly by consuming the API.

In case you're using the private publish mode, make sure you're using the correct api key and are setting the private option to true.

import i18next from "i18next";
import Locize from "i18next-locize-backend";

i18next.use(Locize).init({
  backend: {
    projectId: "[PROJECTID]",
    apiKey: "[APIKEY]",
    version: "[VERSION]",
    private: true,
    referenceLng: "en"
  }
});

On server side: process is not exiting

In case you want to use i18next-locize-backend on server side for a short running process, you might want to set the reloadInterval option to false:

{
  reloadInterval: false,
  projectId: "[PROJECTID]",
  version: 'latest',
  referenceLng: 'en',
}

Not all languages are loaded

By default the supportedLngs are defined by having a minimum of 90% of done translations. You can set a threshold for languages to be added to supportedLngs by setting translatedPercentageThreshold in backend options (eg: 1 = 100% translated, 0.9 = 90% translated).

Getting started

Source can be loaded via npm, yarn, bower or downloaded from this repo.

# npm package
$ npm install i18next-locize-backend

# yarn
$ yarn add i18next-locize-backend

# bower
$ bower install i18next-locize-backend

Wiring up:

import i18next from 'i18next';
import Locize from 'i18next-locize-backend';
// or
const i18next = require('i18next');
const Locize = require('i18next-locize-backend');

i18next.use(Locize).init(i18nextOptions);

for Deno:

import i18next from 'https://deno.land/x/i18next/index.js'
import Backend from 'https://deno.land/x/i18next_locize_backend/index.js'

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.i18nextLocizeBackend

Backend Options

IMPORTANT make sure you do not add your apiKey in the production build to avoid misuse by strangers

{
  // the id of your locize project
  projectId: '[PROJECTID]',

  // add an api key if you want to send missing keys
  apiKey: '[APIKEY]',

  // the reference language of your project
  referenceLng: '[LNG]',

  // version - defaults to latest
  version: '[VERSION]',

  // private - set to true if you version on locize is set to use private publish
  private: false,

  // hostnames that are allowed to create, update keys
  // please keep those to your local system, staging, test servers (not production)
  // can be array of allowed hosts or a function (hostname) => { return true; // or false if not allowed }
  allowedAddOrUpdateHosts: ['localhost'],

  // optional event triggered on saved to backend
  onSaved: (lng, ns) => { ... },

  // can be used to reload resources in a specific interval (useful in server environments)
  reloadInterval: typeof window !== 'undefined' ? false : 60 * 60 * 1000,

  // define the threshold for languages to be added to supportedLngs (eg: 1 = 100% translated, 0.9 = 90% translated [default]).
  translatedPercentageThreshold: 0.8,

  // define a custom request function
  // can be used to support Angular http client
  //
  // 'info' contains 'url', 'method', 'body' and 'headers'
  //   'url' the url that should be requested
  //   'method' GET for fetching translations and POST for saving missing translations
  //   'body' will be a key:value object used when saving missing translations
  //   'headers' will be a key:value object containing the header information that should be sent
  // 'callback' is a function that takes two parameters, 'err' and 'res'.
  //            'err' should be an error
  //            'res' should be an object with a 'status' property and a 'data' property containing a stringified object instance beeing the key:value translation pairs for the
  //            requested language and namespace, or null in case of an error.
  request: function (info, callback) {},
  // or async / promise
  //request: async (info) {},
}

To load translations only projectId needs to be filled. To use the saveMissing feature of i18next additional to the projectId both apiKey and referenceLng have to be set.

Options can be passed in:

preferred - by setting options.backend in i18next.init:

import i18next from "i18next";
import Locize from "i18next-locize-backend";

i18next.use(Locize).init({
  backend: options
});

on construction:

import Locize from "i18next-locize-backend";
const locize = new Locize(options);

via calling init:

import Locize from "i18next-locize-backend";
const locize = new Locize();
locize.init(options);

Additional API endpoints

backend.getLanguages

Will return a list of all languages in your project including percentage of translations done per version.

import Locize from "i18next-locize-backend";
const locize = new Locize(options);

locize.getLanguages((err, data) => {
  /*
  data is:

  {
    "en": {
      "name": "English",
      "nativeName": "English",
      "isReferenceLanguage": true,
      "translated": {
        "latest": 1
      }
    },
    "de": {
      "name": "German",
      "nativeName": "Deutsch",
      "isReferenceLanguage": false,
      "translated": {
        "latest": 0.9
      }
    }
  }
  */
});

// or
const data = await locize.getLanguages();

// or
i18next.services.backendConnector.backend.getLanguages(callback);

// or
const data = await i18next.services.backendConnector.backend.getLanguages();

backend.getOptions

Will return an object containing useful informations for the i18next init options.

import Locize from "i18next-locize-backend";
const locize = new Locize(options);

locize.getOptions((err, data) => {
  /*
  data is:

  {
    fallbackLng: 'en',
    referenceLng: 'en',
    supportedLngs: ['en', 'de'],
    load: 'languageOnly|all' // depending on your supportedLngs has locals having region like en-US
  }
  */
});

// or
const data = await locize.getOptions();

// or
i18next.services.backendConnector.backend.getOptions(callback);

// or
const data = await i18next.services.backendConnector.backend.getOptions();

You can set a threshold for languages to be added to supportedLngs by setting translatedPercentageThreshold in backend options (eg: 1 = 100% translated, 0.9 = 90% translated).

SPECIAL - let the backend determine some options to improve loading

You can load some information from the backend to eg. set supportedLngs for i18next just supporting languages you got in your locize project.

You will get i18next options for (same as above backend.getOptions):

  • fallbackLng
  • supportedLngs
  • load
import i18next from "i18next";
import Locize from "i18next-locize-backend";

const locize = new Locize(
  {
    projectId: "[PROJECTID]",
    apiKey: "[APIKEY]",
    version: "[VERSION]"
    // referenceLng -> not needed as will be loaded from API
  },
  (err, opts, lngs) => {
    i18next.use(locize).init({ ...opts, ...yourOptions }); // yourOptions should not include backendOptions!
  }
);

Special usage with react-i18next without using Suspense

Use setI18n to pass in the i18next instance before initializing:

import i18n from "i18next";
import { initReactI18next, setI18n } from "react-i18next";
import LocizeBackend from "i18next-locize-backend";

const backendOptions = {
  projectId: "1d0aa5aa-4660-4154-b6d9-907dbef10bb3"
};

const yourOptions = {
  debug: true,
  interpolation: {
    escapeValue: false
  },
  react: {
    useSuspense: false
  }
};

// this is only used if not using suspense
i18n.options.react = yourOptions.react;
setI18n(i18n);

const backend = new LocizeBackend(backendOptions, (err, opts) => {
  if (err) return console.error(err);
  i18n
    .use(backend)
    // .use(initReactI18next) // keep this if using suspense
    // yourOptions should not include backendOptions!
    .init({ ...opts, ...yourOptions }, (err, t) => {
      if (err) return console.error(err);
    });
});

export default i18n;

IMPORTANT ADVICE FOR SERVERLESS environments - AWS lambda, Google Cloud Functions, Azure Functions, etc...

Please be aware

Due to how serverless functions work, you cannot guarantee that a cached version of your data is available. Serverless functions are short-lived, and can shut down at any time, purging any in-memory or filesystem cache. This may be an acceptable trade-off, but sometimes it isn't acceptable.

Because of this we suggest to download the translations in your CI/CD pipeline (via cli or via api) and package them with your serverless function.

For example with i18next-fs-backend

import i18next from 'i18next';
import Backend from 'i18next-fs-backend';

const backend = new Backend({
  // path where resources get loaded from
  loadPath: '/locales/{{lng}}/{{ns}}.json'
});

i18next
  .use(backend)
  .init({
    // initImmediate: false, // setting initImediate to false, will load the resources synchronously
    ...opts,
    ...yourOptions
  }); // yourOptions should not include backendOptions!

or just import/require your files directly

import i18next from 'i18next';
import en from './locales/en.json'
import de from './locales/de.json'

i18next
  .init({
    ...opts,
    ...yourOptions,
    resources: {
      en,
      de
    }
  });

TypeScript

To properly type the backend options, you can import the LocizeBackendOptions interface and use it as a generic type parameter to the i18next's init method, e.g.:

import i18n from 'i18next'
import LocizeBackend, { LocizeBackendOptions } from 'i18next-locize-backend'

i18n
  .use(LocizeBackend)
  .init<LocizeBackendOptions>({
    backend: {
      // locize backend options
    },

    // other i18next options
  })

changelog

7.0.4

  • fix promise api for getLanguages

7.0.3

  • optimize fetchApi selector

7.0.2

  • fix getOptions to return reference language in the supportedLngs if there are no languages found yet

7.0.1

  • try to get rid of top-level await

7.0.0

  • fix for Deno 2 and removal of unnecessary .cjs file
  • for esm build environments not supporting top-level await, you should import the i18next-locize-backend/cjs export or stay at v6.5.2

6.5.5

  • optimize fetchApi selector [backported]

6.5.3

  • fix getOptions to return reference language in the supportedLngs if there are no languages found yet [backported]

6.5.2

  • improve network error detection across browsers

6.5.1

  • optimize "Failed to fetch" retry case

6.5.0

  • optimize "Failed to fetch" retry case

6.4.3

  • dereference timers in node.js so that the process may exit when finished

6.4.2

  • fix: remove typeof window.document === 'undefined' check which deopt bundle optimization

6.4.1

  • fix: separate cjs and mjs typings

6.3.1

  • fix for browser usage

6.3.0

  • update deps

6.2.3

  • hack for debug mode in react-native

6.2.2

  • fix for types moduleResolution "node16"

6.2.1

  • exported some type definitions

6.2.0

  • possibility to define custom request function, can be used to support Angular http client #351

6.1.1

  • typescript: fix old declaration of plugin

6.1.0

  • typescript: export the backend options type

6.0.1

  • typescript: static type prop

6.0.0

  • typescript fix for i18next v22

5.1.5

  • update dependencies
  • define types also in exports

5.1.4

  • error if no fetch and no xhr implementation found

5.1.3

  • warn for low reloadInterval values

5.1.2

  • also check for fallbackLng if no referenceLng is found

5.1.1

  • fix detecting referenceLng if only getLanguages function is used

5.1.0

  • promise api for getLanguages and getOptions

5.0.1

  • optimize internal checkIfProjectExists call, when requesting a lot of requests, i.e. multiple namespaces etc.

5.0.0

  • remove old deprecated options: whitelist->supportedLngs and whitelistThreshold->translatedPercentageThreshold

4.3.0

  • limit the number of preflight requests by CORS #346

4.2.8

  • getOptions: return also languages result

4.2.7

  • update dependencies

4.2.6

  • ensure optional callback for create is called

4.2.5

  • default console logger if not available

4.2.4

  • ignore document.cookie errors

4.2.3

  • update dependencies
  • decrease default write debounce

4.2.2

  • replace internal node-fetch with cross-fetch

4.2.0

  • Type PluginOptions properly
  • update dependencies

4.1.10

  • fix types constructor and init signatures
  • update dependencies

4.1.9

  • XMLHttpRequest fix for ios < 9

4.1.8

  • better default for reloadInterval

4.1.7

  • first first check of reloadInterval

4.1.6

  • update dependencies

4.1.5

  • ts: allowedAddOrUpdateHosts

4.1.4

  • ts: fix referenceLng option

4.1.3

  • ts: reloadInterval option

4.1.2

  • fix for retry logic

4.1.1

  • transpile also esm

4.1.0

  • rename option whitelist to supportedLngs
  • rename option whitelistThreshold to translatedPercentageThreshold

This changes are made with temporal backwards compatiblity and will warn your for deprecated usage of old terms to give users and plugin providers some time to adapt their code base.

The temporal backwards compatiblity will be removed in a follow up major release.

Learn more about why this change was made here.

4.0.13

  • fix callback types

4.0.12

  • fix xhr response handling

4.0.11

  • do not try to load node-fetch in browser

4.0.10

  • fix for non-fetch browsers using i18nextLocizeBackend.js

4.0.9

  • replace spread operator with defaults function

4.0.8

  • fix exports for react-native

4.0.7

  • dedicated export for node v14

4.0.6

  • check for logger to exist

4.0.5

  • fix checkIfProjectExists callback

4.0.4

  • fix for react-native

4.0.3

  • warning for using saveMissing or updateMissing feature on a host not beeing localhost

4.0.2

  • fix for bundlers like rollup

4.0.0

  • complete refactoring to make this module universal (replaces i18next-node-locize-backend)

3.1.3

  • page missing request

3.1.2

  • make sure checkIfProjectExists is not called, while waiting for response

3.1.1

  • fix for non-browser usage

3.1.0

  • check if project exists

3.0.3

  • retry on 400 status

3.0.2

  • retry on 408 status

3.0.1

  • fix allowedAddOrUpdateHosts function failure log 317

3.0.0

  • using the new locize.app domain replacing the deprecated locize.io domain
  • removed the deprecated pull API keeping a warning to use private option instead
  • updated dev dependencies

2.2.2

  • warn for missing options

2.2.1

  • check for window type 312

2.2.0

  • allow allowedAddOrUpdateHosts to be a function returning true if allowed or false if not allowed host

2.1.0

  • emit a onSaved(lng, ns) event if in options

2.0.2

  • small fixes in warn logic

2.0.1

  • give warnings when save missing does block the saving because reference language was not found or the allowed hosts did not contain the host

2.0.0

  • removes deprecated jsnext:main from package.json
  • Bundle all entry points with rollup 303
  • note: dist/es -> dist/esm, dist/commonjs -> dist/cjs (individual files -> one bundled file)
  • removes bower finally

v1.9.0

  • allow to define a list of allowed hosts to send lastUsed data - defaults to localhost

v1.8.0

  • handle empty result as an error if failLoadingOnEmptyJSON set true 299

v1.7.1

  • main export index.d.ts as default export

v1.7.0

  • adds index.d.ts for typescript users

v1.6.0

  • support for private versions

v1.5.0

  • experimental option to use pull api route during development

v1.4.2

  • fix typo in package.json

v1.4.1

  • fix getLanguages route to return error on not getting data

v1.4.0

  • adds getOptions route
  • add special construction with callback to autoload possible i18next options.

v1.3.1

  • fixes debounced write to send every namespace-language pair

v1.3.0

  • supports submitting options tDescription (context) i18next >= 10.4.1

v1.2.1

  • use content-type in case of POST request

v1.2.0

  • make the content-type optional using option.setContentTypeJSON

v1.1.0

  • adds update function
  • adds compatibility to i18next options updateMissing

v1.0.0

  • adds module entry point for webpack2
  • updates all it's build dependencies
  • optimize rollbar build to use es2015 transpile