@commercetools-frontend/l10n

React bindings to load l10n data.

Install

``bash
$ npm install --save @commercetools-frontend/l10n
`

Supported locales

- en
- de
- es
- fr-FR

Hooks

`js
import {
useCountries,
useCurrencies,
useLanguages,
useTimeZones,
} from '@commercetools-frontend/l10n';

const { isLoading, data, error } = useCountries('en');
`

Higher Order Components

`js
import { withCountries } from '@commercetools-frontend/l10n';

withCountries((ownProps) => ownProps.locale)(Component);

// format: { countryCode: countryLabel }
// { "de":"Germany" }
`

`js
import { withCurrencies } from '@commercetools-frontend/l10n';

withCurrencies((ownProps) => ownProps.locale)(Component);

// format: { currencyCode: { label, symbol } }
// { "EUR": { "label": "Euro", "symbol": "€" } }
`

`js
import { withLanguages } from '@commercetools-frontend/l10n';

withLanguages((ownProps) => ownProps.locale)(Component);

// format: { languageCode: { language, country? } }
// Case with main language
// { "es": { "language": "Spanish" } }
// Case with language of a region
// { "es-AR": { "language": "Spanish", "country": "Argentina" } }
`

`js
import { withTimeZones } from '@commercetools-frontend/l10n';

withTimeZones((ownProps) => ownProps.locale)(Component);

// format: { timezone: { name, abbr, offset } }
// Case with main language
// { "es": { "Europe/Berlin": { "name": "Europe/Berlin", "abbr": "CEST", "offset": "+02:00" } } }
// Case with language of a region
// { "fr-FR": { "Europe/Berlin": { "name": "Europe/Berlin", "abbr": "CEST", "offset": "+02:00" } } }
// { "es-AR": { "Europe/Berlin": { "name": "Europe/Berlin", "abbr": "CEST", "offset": "+02:00" } } }
`

Generating localization data

The data directory contains all the localization data for the supported locales. The data is generated using the script scripts/generate-l10n-data.js, which uses the cldr data.

#### Using a custom version of the cldr data

In case the npm library cldr does not contain the latest cldr data, we can manually download it and point the cldr library to use that data.

`js
// For example, using the v35 of cldr
const cldr = require('cldr').load(path.join(__dirname, '../cldr-v35'));
`

First, download the data (core.zip) for a specific version from the downloads page.

Then extract the data and copy the core folder to this package, and rename it to e.g. cldr-v35. Then point the cldr library to the folder location.

Run the script, which uses the new data.

#### Generating Time Zone Data

Translations for time zones are located in data/time-zones/. There is a core.json and a file for each supported locale (.json). Transifex integration for these translations will be added in a subsequent PR.

Only some time zones have translations. For those time zones that have not been translated, each have been mapped to a time zone that does have a translation in data/time-zones/translations-map.json. This ensures that each IANA time zone identifier returned by moment.tz.names() will show an accurate translation.

The IANA peridically updates its' list of timezones. When the IANA releases a new set of time zones, it will be added to moment-timezone.

When generate-l10n-data is run, it gets the list of all time zones being returned by moment-timezone by running moment.tz.names(), and compares it to the list of translated (included) and mapped (excluded) time zones in core.json and translations-map.json.

For each unhandled time zone returned, CLI will prompt the user to either translate, exclude, or ignore it.

If the user selects translate, they must enter an english language translation string. That string will then be added to core.json and each .json for subsequent translation. It will also be added as a key in translations-map.json so that subsequent time zones can be mapped to its' translation if they are excluded.

If the user selects exclude, they must enter the IANA time zone id of a time zone that currently has a translation in order to map the time zone to a translation string. The excluded translation is then added to the array for the give translated time zone in translations-map.json, e.g.:
"America/New_York": ["EST", "EDT"]

If the user selects ignore, the unhandled time zone will be ignored until the generate-l10n-data script is run again.

Utils

$3

> Transforms multiple LocalizedField -> LocalizedString, given fieldNameTransformationMappings

#### Context

Amongst Common Types in the commercetools platform API, we find LocalizedString type.

The LocalizedString is a type reserved for values found in a Resource, for example Product:

`js
// Product
{
// name is a LocalizedString
// as defined by https://docs.commercetools.com/api/projects/products#productdata
name: {
en: 'Milk';
}
}
`

The documented LocalizedString in https://docs.commercetools.com is a specification of the HTTP API.

However, the commercetools platform /graphql API represents the LocalizedString as a list of the same name.

`js
// Product, returned from the /graphql API of commercetools platform
{
nameAllLocales: [
{
locale: 'en',
value: 'Milk',
},
];
}
`

To distinguish these in source code of the Merchant Center, we name the graphql shaped value LocalizedField. We offer applyTransformedLocalizedFields that is authored to transform these values from one to the other.

#### Example usage

`js
const product = {
nameAllLocales: [
{
locale: 'en',
value: 'Milk',
},
],
descriptionAllLocales: [
{
locale: 'en',
value: 'This is milk',
},
],
};
const fieldNameTransformationMappings = [
{
from: 'nameAllLocales',
to: 'name',
},
{
from: 'descriptionAllLocales',
to: 'description',
},
];
const transformedProduct = applyTransformedLocalizedFields(
fetchedProduct,
fieldNameTransformationMappings
);

console.log(transformedProduct);
// { name: { en: 'Milk' }, description: { en: 'This is milk' } }
`

#### When to use it

This transformation tool will be helpful when you consume the commercetools platform /graphql API in conjunction with authoring views consuming @commercetools-frontend/ui-kit.

Given that you consume:

- The commercetools platform /graphql API
- LocalizedTextInput

This will be helpful transforming data from response -> view.

`js
// fetching product from the commercetools platform /graphql API
// returns a product with a nameAllLocales and descriptionAllLocales
const product = useMcQuery(ProductQuery, {
context: GRAPHQL_TARGETS.COMMERCETOOLS_PLATFORM,
});

// Given that LocalizedTextInput accepts a value of { [key: string]: string },
// we tranform our product to match the required shape
const transformedProduct = applyTransformedLocalizedFields(
product,
fieldNameTransformMappings
);

// Finally, we are ready to render our form with the correctly shaped name and description
return (
<>

name="description"
value={transformedProduct.description}
/>

);
`

$3

> Transforms a LocalizedString to a String

The formatLocalizedString util is a util we use internally inside the Merchant Center. This util is at the moment subject to change, hence marked as Draft.

#### Context

As discussed under applyTransformedLocalizedFields, a LocalizedString is a value type reserved for a Resource, e.g a Product.

`js
const product = {
name: {
en: 'Milk',
de: 'Milch',
},
};
`

When rendering a Product in a view, we would like to render the value of a localized string field, such as name, given the selected data locale of the UI.
The data locale is a value controlled by the Merchant Center User (MC User) by changing the data locale switcher in the top bar of the Merchant Center. The list of available options is derived by the list of languages specified in the project. The selected value can be read from the application context.

However, there might be a case where the selected data locale does not match any of the localized string values. In this case, it is recommended to display a "fallback" value using the formatLocalizedString function.

The formatLocalizedString util is authored with the following in mind:

1. Help deriving a value of LocalizedString given a specified locale.
2. Help rendering a value derived from LocalizedString.

Let us take a look at the examples below putting this to action.

#### Example usage

All examples below will use the following Product:

`
const product = {
name: {
en: 'Milk',
de: 'Milch,
}
}
`

##### Scenario 1

Given that selected data locale of de

`js
const translatedName = formatLocalizedString(product, {
key: 'name',
locale: 'de',
});

console.log(translatedName);
// 'Milch'
`

##### Scenario 2

Given that selected data locale of sv

`js
const translatedName = formatLocalizedString(product, {
key: 'name',
locale: 'sv',
});

console.log(translatedName);
// 'Milk (EN)'
`

What happened?

Our product has no value for the selected data locale sv. The formatLocalizedString function selects the "next available value" (more details on the order below) from product.name. In this case it's en, and returns it with a hint (EN) that this value refers to another locale.

##### Scenario 3

Given that selected data locale of de-AT

`js
const translatedName = formatLocalizedString(product, {
key: 'name',
locale: 'de-AT',
});

console.log(translatedName);
// 'Milch'
`

What happened?

Our product has no matching value for the selected data locale de-AT but we still got "Milch".
This is because formatLocalizedString attempts to determine a primary language tag on the option locale and match that to the available values. Given that de is a primary of de-AT, it determines that this is the _closest available value_ from product.name

#### Fallback

To provide even more freedom beyond cases mentioned above the formatLocalizedString allows specifying a fallback as a last resort:

`js
const translatedName = formatLocalizedString(product, {
obj: product,
key: 'name',
locale: 'sv',
fallback: '-',
});
`

The default value of fallback is a "".

#### Fallback order

In Scenario 2 above, we discussed that formatLocalizedString will pick the "next available value" from product.name when there is no matching value. In our case, the next available value was the locale en.
Merchant Center customizations developers can take full control over the order of attempted lookups of the value while there is no match. Before formatLocalizedString eventually proceeds to rendering what is specified as fallback.

formatLocalizedString accepts fallbackOrder, and this test exemplifies the use case and resolve.

#### When to use it

Given that we want to render LocalizedString of a given Resource, it is sensible to rely on formatLocalizedString in conjunction with the Application Context. A user usually has a defined preference of languages we can use.

`js
import Text from '@commercetools-uikit/text';
import { useApplicationContext } from '@commercetools-frontend/application-shell-connectors';

const { dataLocale, projectLanguages } = useApplicationContext(
(applicationContext) => ({
dataLocale: applicationContext.dataLocale,
// The Application Context also exposes the languages that are defined on the Project settings
// we can rely on this to determine the fallback order.
// This helps with consistency, although you can specify the fallback order however you want
projectLanguages: context.project.languages,
})
);

return (

{formatLocalizedString(product, {
key: 'name',
locale: dataLocale,
fallback: '',
fallbackOrder: projectLanguages,
})}

);
``