1. The configuration code for the i18n application component is as follows:
'components' => [
'i18n' => [
'translations' => [
'model/*' => [
'class' => 'yii\i18n\PhpMessageSource',
'forceTranslation' => true,
'basePath' => '@common/messages',
],
'*' => [
'class' => 'yii\i18n\PhpMessageSource',
'forceTranslation' => true,
'basePath' => '@app/messages',
'fileMap' => [
'app' => 'app.php',
'error' => 'error.php',
'success' => 'success.php',
],
],
],
],
],
2. Request the API in Postman. In the Headers, set Accept-Language:zh-CN. When the target language is Simplified Chinese and the file mapping category name is success, it is mapped to the PHP file @app/messages/zh-CN/success.php, as shown in Figure 1.
return ['code' => 10000, 'message' => Yii::t('success', '127016'), 'data' => ['items' => array_values($models)]];
3. Request the API in Postman. In the Headers, set Accept-Language:zh-CN. When the target language is Simplified Chinese and the file mapping category name is app, it is mapped to the PHP file @app/messages/zh-CN/app.php, as shown in Figure 2.
$planLog->opinion = Yii::t('app', Yii::t('app', Yii::t('app', 302016), ['accepted_group_name' => $acceptedGroupName, 'accepted_user_nick' => $identity->user_nick]));
4. Request the API in Postman. In the Headers, set Accept-Language:en-US. When the target language is American English and the file mapping category name is success, it is mapped to the PHP file @app/messages/en-US/success.php, as shown in Figure 3.
5. Request the API in Postman. In the Headers, set Accept-Language:en-US. When the target language is American English and the file mapping category name is app, it is not mapped to the PHP file @app/messages/en-US/app.php. The message to be translated is not found in the language file, so the original untranslated message is returned, namely: 302011. As shown in Figure 4.
6. Edit E:\wwwroot\pcs-api\vendor\yiisoft\yii2\i18n\MessageSource.php. When the target language is Simplified Chinese, the response is: 11. When the target language is American English, the response is: 21. That is, when the target language is American English and the file mapping category name is app, the step of translating the specified message is skipped. As shown in Figure 5 and Figure 6.
Yii::t('app', '302011');
exit;
public function translate($category, $message, $language)
{
if ($this->forceTranslation || $language !== $this->sourceLanguage) {
echo 1;
exit;
return $this->translateMessage($category, $message, $language);
}
echo 2;
exit;
return false;
}
7. When the target language is American English and the file mapping category name is app, the value of $this->forceTranslation is false, as shown in Figure 7.
public function translate($category, $message, $language)
{
var_dump($this->forceTranslation);
exit;
if ($this->forceTranslation || $language !== $this->sourceLanguage) {
echo 1;
exit;
return $this->translateMessage($category, $message, $language);
}
echo 2;
exit;
return false;
}
8. When the target language is American English and the file mapping category name is success, the value of $this->forceTranslation is true, as shown in Figure 8.
Yii::t('success', '302011');
exit;
9. Review \vendor\yiisoft\yii2\i18n\I18N.php. The file mapping category names yii and app always define the categories yii and app. The former refers to the message framework code used in the Yii core, while the latter refers to the default message category for custom application code. It checks whether the category app exists, and overrides it if it does not. However, this check only applies to the first level and does not go deeper. Therefore, the custom category app is overridden, as shown in Figure 9.
/**
* @var array list of [[MessageSource]] configurations or objects. The array keys are message
* category patterns, and the array values are the corresponding [[MessageSource]] objects or the configurations
* for creating the [[MessageSource]] objects.
*
* The message category patterns can contain the wildcard `*` at the end to match multiple categories with the same prefix.
* For example, `app/*` matches both `app/cat1` and `app/cat2`.
*
* The `*` category pattern will match all categories that do not match any other category patterns.
*
* This property may be modified on the fly by extensions who want to have their own message sources
* registered under their own namespaces.
*
* The category `yii` and `app` are always defined. The former refers to the messages used in the Yii core
* framework code, while the latter refers to the default message category for custom application code.
* By default, both of these categories use [[PhpMessageSource]] and the corresponding message files are
* stored under `@yii/messages` and `@app/messages`, respectively.
*
* You may override the configuration of both categories.
*/
public $translations;
/**
* Initializes the component by configuring the default message categories.
*/
public function init()
{
parent::init();
if (!isset($this->translations['yii']) && !isset($this->translations['yii*'])) {
$this->translations['yii'] = [
'class' => 'yii\i18n\PhpMessageSource',
'sourceLanguage' => 'en-US',
'basePath' => '@yii/messages',
];
}
if (!isset($this->translations['app']) && !isset($this->translations['app*'])) {
$this->translations['app'] = [
'class' => 'yii\i18n\PhpMessageSource',
'sourceLanguage' => Yii::$app->sourceLanguage,
'basePath' => '@app/messages',
];
}
}
10. The solution is as follows: change the file mapping category name from app to application, so it is mapped to the PHP file application.php. Update the configuration code for the i18n application component as follows:
'components' => [
'i18n' => [
'translations' => [
'model/*' => [
'class' => 'yii\i18n\PhpMessageSource',
'forceTranslation' => true,
'basePath' => '@common/messages',
],
'*' => [
'class' => 'yii\i18n\PhpMessageSource',
'forceTranslation' => true,
'basePath' => '@app/messages',
'fileMap' => [
'application' => 'application.php',
'error' => 'error.php',
'success' => 'success.php',
],
],
],
],
],
11. Rename the file \common\messages\en-US\app.php to \common\messages\en-US\application.php, rename the file \common\messages\zh-CN\app.php to \common\messages\zh-CN\application.php, rename the file \api\messages\en-US\app.php to \api\messages\en-US\application.php, and rename the file \api\messages\zh-CN\app.php to \api\messages\zh-CN\application.php. Do the same for all other application directories. Batch replace Yii::t(‘app’, with Yii::t(‘application’,. As shown in Figure 10.
12. When the target language is American English and the file mapping category name is application, it is now mapped to the PHP file @app/messages/en-US/application.php, as shown in Figure 11.
