AssetConverter

API reference › yii › web › AssetConverter

class	`yii\web\AssetConverter`
Extends	`yii\base\Component` » `yii\base\BaseObject`
Implements	`AssetConverterInterface`, `yii\base\Configurable`
Since	2.0
Source	`framework/web/AssetConverter.php`

AssetConverter supports conversion of several popular formats into JS or CSS files.

It is used by AssetManager to convert files after they have been published.

Properties

Property	Type	Description	Defined by
`$behaviors` read-only	`array<yii\base\Behavior<static>>`	List of behaviors attached to this component.	`yii\base\Component`
`$commands`	`array`	The commands that are used to perform the asset conversion. Default: `['less' => ['css', 'lessc {from} {to} --no-color --source-map'], 'scss' => ['css', 'sass --style=compressed {from} {to}'], 'sass' => ['css', 'sass --style=compressed {from} {to}'], 'styl' => ['css', 'stylus < {from} > {to}'], 'coffee' => ['js', 'coffee -p {from} > {to}'], 'ts' => ['js', 'tsc --out {to} {from}']]`.	`AssetConverter`
`$forceConvert`	`bool`	Whether the source asset file should be converted even if its result already exists. Default: `false`.	`AssetConverter`

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`
`convert()`	Converts a given asset file into a CSS or JS file.	`AssetConverter`
`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 object.	`yii\base\BaseObject`
`off()`	Detaches an existing event handler from this component.	`yii\base\Component`
`on()`	Attaches an event handler to an event.	`yii\base\Component`
`trigger()`	Triggers an event.	`yii\base\Component`
`runCommand()` protected	Runs a command to convert asset files.	`AssetConverter`

Property details

$commands

public array $commands = ['less' => ['css', 'lessc {from} {to} --no-color --source-map'], 'scss' => ['css', 'sass --style=compressed {from} {to}'], 'sass' => ['css', 'sass --style=compressed {from} {to}'], 'styl' => ['css', 'stylus < {from} > {to}'], 'coffee' => ['js', 'coffee -p {from} > {to}'], 'ts' => ['js', 'tsc --out {to} {from}']]

The commands that are used to perform the asset conversion.

The keys are the asset file extension names, and the values are the corresponding target script types (either “css” or “js”) and the commands used for the conversion.

The command placeholders: {from} - source file, {to} - converted file.

You may also use a path alias to specify the location of the command:

[
    'styl' => ['css', '@app/node_modules/bin/stylus < {from} > {to}'],
]

Note: Yii::getAlias() can replace alias at the begin of the command only.

$forceConvert

public bool $forceConvert = false

Whether the source asset file should be converted even if its result already exists.

You may want to set this to be true during the development stage to make sure the converted assets are always up-to-date. Do not set this to true on production servers as it will significantly degrade the performance.

Method details

convert()

public function convert(string $asset, string $basePath): string

Converts a given asset file into a CSS or JS file.

Parameters

Parameter	Type	Description
`$asset`	`string`	The asset file path, relative to $basePath
`$basePath`	`string`	The directory the $asset is relative to.

Returns

string: The converted asset file path, relative to $basePath.

runCommand()

protected function runCommand(string $command, string $basePath, string $asset, string $result): bool

Runs a command to convert asset files.

Parameters

Parameter	Type	Description
`$command`	`string`	The command to run. If prefixed with an `@` it will be treated as a path alias.
`$basePath`	`string`	Asset base path and command working directory
`$asset`	`string`	The name of the asset file
`$result`	`string`	The name of the file to be generated by the converter command

Returns

bool: True on success, false on failure. Failures will be logged.

Throws

yii\base\Exception: when the command fails and YII_DEBUG is true. In production mode the error will be logged.