Use django's gettext in Svelte

Wrapper around django's JavaScript i18n features in Svelte.

Django docs: Using the JavaScript translation catalog

In your rollup configuration:
``JavaScript
import svelte from 'rollup-plugin-svelte';
import { writeGettextExtracts, gettextStringExtractor } from 'svelte-django-gettext/build';

export default {
input: 'app.js',
output: {...},
plugins: [
svelte({
preprocessors: {
markup: gettextStringExtractor
}
}),
writeGettextExtracts('js/_svelte_django_extracted_messages.js'),
]
}
`

Or with vite:

`JavaScript
import { defineConfig } from 'vite';
import { svelte } from '@sveltejs/vite-plugin-svelte';

import { gettextStringExtractor, writeGettextExtracts } from 'svelte-django-gettext/build';

export default defineConfig({
base: '',
plugins: [
svelte({
preprocess: {
markup: gettextStringExtractor
},
}),
writeGettextExtracts('js/_svelte_django_extracted_messages.js'),
],
});
`


In your application:

`Svelte


{gettext('hello')}


`

Make sure the page loads the generated catalog, from a django template: .
If this is not the case, all functions will just return their message id.

How it works:

Django's ./manage.py makemessages cannot parse .svelte files to extract gettext() calls.
A preprocessor extracts gettext() calls and outputs _svelte_django_extracted_messages.js, which then contains gettext calls extracted from your .svelte files.

This file should be added to .gitignore, but Django's makemessages` management command can read translations strings from it.