Yii2 multilingual behavior

Yii2 port of the yii-multilingual-behavior.

This behavior allows you to create multilingual models and almost use them as normal models. Translations are stored in a separate table in the database (ex: PostLang or ProductLang) for each model, so you can add or remove a language easily, without modifying your database.

!!! IMPORTANT !!! Docs for vesions 1. here*

In vesion 2. forceOverwrite property is deprecated*

Examples

Example #1: current language translations are inserted to the model as normal attributes by default.

//Assuming current language is english

$model = Post::findOne(1);
echo $model->title; //echo "English title"

//Now let's imagine current language is french 
$model = Post::findOne(1);
echo $model->title; //echo "Titre en Français"

$model = Post::find()->localized('en')->one();
echo $model->title; //echo "English title"

//Current language is still french here

Example #2: if you use multilingual() in a find() query, every model translation is loaded as virtual attributes (title_en, title_fr, title_de, ...).

$model = Post::find()->multilingual()->one();
echo $model->title_en; //echo "English title"
echo $model->title_fr; //echo "Titre en Français"

Installation

Preferred way to install this extension is through composer.

Either run

php composer.phar require --prefer-dist omgdef/yii2-multilingual-behavior

or add

"omgdef/yii2-multilingual-behavior": "~2.0"

to the require section of your composer.json file.

Behavior attributes

Attributes marked as bold are required

Attribute, Description
----------, ------------
languageField, The name of the language field of the translation table. Default is 'language'
localizedPrefix, The prefix of the localized attributes in the lang table. Is used to avoid collisions in queries. The columns in the translation table corresponding to the localized attributes have to be name like this: [prefix]_[name of the attribute] and the id column (primary key) like this : [prefix]_id
requireTranslations, If this property is set to true required validators will be applied to all translation models.
dynamicLangClass, Dynamically create translation model class. If true, the translation model class will be generated on runtime with the use of the eval() function so no additionnal php file is needed
langClassName, The name of translation model class. Dafault value is model name + Lang
languages, Available languages. It can be a simple array: ['fr', 'en'] or an associative array: ['fr' => 'Français', 'en' => 'English']
defaultLanguage, The default language
langForeignKey, Name of the foreign key field of the translation table related to base model table.
tableName, The name of the translation table
attributes, Multilingual attributes

Usage

Here an example of base 'post' table :

CREATE TABLE IF NOT EXISTS `post` (
    `id` int(11) NOT NULL AUTO_INCREMENT,
    `created_at` datetime NOT NULL,
    `updated_at` datetime NOT NULL,
    `enabled` tinyint(1) NOT NULL DEFAULT '1',
    PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

And its associated translation table (configured as default), assuming translated fields are 'title' and 'content':

CREATE TABLE IF NOT EXISTS `postLang` (
    `id` int(11) NOT NULL AUTO_INCREMENT,
    `post_id` int(11) NOT NULL,
    `language` varchar(6) NOT NULL,
    `title` varchar(255) NOT NULL,
    `content` TEXT NOT NULL,
    PRIMARY KEY (`id`),
    KEY `post_id` (`post_id`),
    KEY `language` (`language`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8;

ALTER TABLE `postLang`
ADD CONSTRAINT `postlang_ibfk_1` FOREIGN KEY (`post_id`) REFERENCES `post` (`id`) ON DELETE CASCADE ON UPDATE CASCADE;

Attaching this behavior to the model (Post in the example). Commented fields have default values.

public function behaviors()
{
    return [
        'ml' => [
            'class' => MultilingualBehavior::className(),
            'languages' => [
                'ru' => 'Russian',
                'en-US' => 'English',
            ],
            //'languageField' => 'language',
            //'localizedPrefix' => '',
            //'requireTranslations' => false',
            //'dynamicLangClass' => true',
            //'langClassName' => PostLang::className(), // or namespace/for/a/class/PostLang
            'defaultLanguage' => 'ru',
            'langForeignKey' => 'post_id',
            'tableName' => "{{%postLang}}",
            'attributes' => [
                'title', 'content',
            ]
        ],
    ];
}

Then you have to overwrite the find() method in your model

    public static function find()
    {
        return new MultilingualQuery(get_called_class());
    }

As this behavior has MultilingualTrait, you can use it in your query classes

namespace app\models;

use yii\db\ActiveQuery;

class MultilingualQuery extends ActiveQuery
{
    use MultilingualTrait;
}

Form example:

//title will be saved to model table and as translation for default language
$form->field($model, 'title')->textInput(['maxlength' => 255]);
$form->field($model, 'title_en')->textInput(['maxlength' => 255]);

Hint: $model has to be populated with translations relative data otherwise translations will not be updated after $form send.