DbMessageSource

API reference › yii › i18n › DbMessageSource

class	`yii\i18n\DbMessageSource`
Extends	`MessageSource` » `yii\base\Component` » `yii\base\BaseObject`
Implements	`yii\base\Configurable`
Since	2.0
Source	`framework/i18n/DbMessageSource.php`

DbMessageSource extends MessageSource and represents a message source that stores translated messages in database.

The database must contain the following two tables: source_message and message.

The source_message table stores the messages to be translated, and the message table stores the translated messages. The name of these two tables can be customized by setting $sourceMessageTable and $messageTable, respectively.

The database connection is specified by $db. Database schema could be initialized by applying migration:

yii migrate --migrationPath=@yii/i18n/migrations/

If you don’t want to use migration and need SQL instead, files for all databases are in migrations directory.

Properties

Property	Type	Description	Defined by
`$behaviors` read-only	`array<yii\base\Behavior<static>>`	List of behaviors attached to this component.	`yii\base\Component`
`$cache`	`yii\caching\CacheInterface\|array\|string`	The cache object or the application component ID of the cache object. Default: `'cache'`.	`DbMessageSource`
`$cachingDuration`	`int`	The time in seconds that the messages can remain valid in cache. Default: `0`.	`DbMessageSource`
`$db`	`yii\db\Connection\|array\|string`	The DB connection object or the application component ID of the DB connection. Default: `'db'`.	`DbMessageSource`
`$enableCaching`	`bool`	Whether to enable caching translated messages Default: `false`.	`DbMessageSource`
`$forceTranslation`	`bool`	Whether to force message translation when the source and target languages are the same. Default: `false`.	`MessageSource`
`$messageTable`	`string`	The name of the translated message table. Default: `'{{%message}}'`.	`DbMessageSource`
`$sourceLanguage`	`string\|null`	The language that the original messages are in. Default: `null`.	`MessageSource`
`$sourceMessageTable`	`string`	The name of the source message table. Default: `'{{%source_message}}'`.	`DbMessageSource`

Methods

Method	Description	Defined by
`__construct()`	Constructor.	`yii\base\BaseObject`
`__call()`	Calls the named method which is not a class method.	`yii\base\Component`
`__clone()`	This method is called after the object is created by cloning an existing one.	`yii\base\Component`
`__get()`	Returns the value of a component property.	`yii\base\Component`
`__isset()`	Checks if a property is set, i.e. defined and not null.	`yii\base\Component`
`__set()`	Sets the value of a component property.	`yii\base\Component`
`__unset()`	Sets a component property to be null.	`yii\base\Component`
`attachBehavior()`	Attaches a behavior to this component.	`yii\base\Component`
`attachBehaviors()`	Attaches a list of behaviors to the component.	`yii\base\Component`
`behaviors()`	Returns a list of behaviors that this component should behave as.	`yii\base\Component`
`canGetProperty()`	Returns a value indicating whether a property can be read.	`yii\base\Component`
`canSetProperty()`	Returns a value indicating whether a property can be set.	`yii\base\Component`
`className()` static	Returns the fully qualified name of this class.	`yii\base\BaseObject`
`detachBehavior()`	Detaches a behavior from the component.	`yii\base\Component`
`detachBehaviors()`	Detaches all behaviors from the component.	`yii\base\Component`
`ensureBehaviors()`	Makes sure that the behaviors declared in `behaviors()` are attached to this component.	`yii\base\Component`
`getBehavior()`	Returns the named behavior object.	`yii\base\Component`
`getBehaviors()`	Returns all behaviors attached to this component.	`yii\base\Component`
`hasEventHandlers()`	Returns a value indicating whether there is any handler attached to the named event.	`yii\base\Component`
`hasMethod()`	Returns a value indicating whether a method is defined.	`yii\base\Component`
`hasProperty()`	Returns a value indicating whether a property is defined for this component.	`yii\base\Component`
`init()`	Initializes the DbMessageSource component.	`DbMessageSource`
`off()`	Detaches an existing event handler from this component.	`yii\base\Component`
`on()`	Attaches an event handler to an event.	`yii\base\Component`
`translate()`	Translates a message to the specified language.	`MessageSource`
`trigger()`	Triggers an event.	`yii\base\Component`
`createFallbackQuery()` protected	The method builds the `Query` object for the fallback language messages search.	`DbMessageSource`
`loadMessages()` protected	Loads the message translation for the specified language and category.	`DbMessageSource`
`loadMessagesFromDb()` protected	Loads the messages from database.	`DbMessageSource`
`translateMessage()` protected	Translates the specified message.	`MessageSource`

Events

Event	Type	Description	Defined by
`EVENT_MISSING_TRANSLATION`	`MissingTranslationEvent`	An event that is triggered when a message translation is not found. Event name: `'missingTranslation'`.	`MessageSource`

Property details

$cache

public yii\caching\CacheInterface|array|string $cache = 'cache'

The cache object or the application component ID of the cache object.

The messages data will be cached using this cache object. Note, that to enable caching you have to set $enableCaching to true, otherwise setting this property has no effect.

After the DbMessageSource object is created, if you want to change this property, you should only assign it with a cache object.

Starting from version 2.0.2, this can also be a configuration array for creating the object.

$cachingDuration

public int $cachingDuration = 0

The time in seconds that the messages can remain valid in cache.

Use 0 to indicate that the cached data will never expire.

$db

public yii\db\Connection|array|string $db = 'db'

The DB connection object or the application component ID of the DB connection.

After the DbMessageSource object is created, if you want to change this property, you should only assign it with a DB connection object.

Starting from version 2.0.2, this can also be a configuration array for creating the object.

Method details

init()

public function init(): mixed

Initializes the DbMessageSource component.

This method will initialize the $db property to make sure it refers to a valid DB connection. Configured $cache component would also be initialized.

Returns

mixed

Throws

yii\base\InvalidConfigException: if $db is invalid or $cache is invalid.

createFallbackQuery()

protected function createFallbackQuery(string $category, string $language, string $fallbackLanguage): yii\db\Query

The method builds the Query object for the fallback language messages search.

Normally is called from loadMessagesFromDb().

Parameters

Parameter	Type	Description
`$category`	`string`	The message category
`$language`	`string`	The originally requested language
`$fallbackLanguage`	`string`	The target fallback language

Returns

yii\db\Query

Since

2.0.7

See also

loadMessagesFromDb()

loadMessages()

protected function loadMessages(string $category, string $language): array

Loads the message translation for the specified language and category.

If translation for specific locale code such as en-US isn’t found it tries more generic en.

Parameters

Parameter	Type	Description
`$category`	`string`	The message category
`$language`	`string`	The target language

Returns

array: The loaded messages. The keys are original messages, and the values are translated messages.

loadMessagesFromDb()

protected function loadMessagesFromDb(string $category, string $language): array

Loads the messages from database.

You may override this method to customize the message storage in the database.

Parameters

Parameter	Type	Description
`$category`	`string`	The message category.
`$language`	`string`	The target language.

Returns

array: The messages loaded from database.