# Class yii\log\Logger

Inheritance | yii\log\Logger » yii\base\Component » yii\base\BaseObject
Implements | yii\base\Configurable
Available since version | 2.0
Source Code | https://github.com/yiisoft/yii2/blob/master/framework/log/Logger.php

Logger records logged messages in memory and sends them to different targets if $dispatcher is set.

A Logger instance can be accessed via `Yii::getLogger()`. You can call the method log() to record a single log message. For convenience, a set of shortcut methods are provided for logging messages of various severity levels via the Yii class:

- Yii::trace()
- Yii::error()
- Yii::warning()
- Yii::info()
- Yii::beginProfile()
- Yii::endProfile()

For more details and usage information on Logger, see the guide article on logging.

When the application ends or $flushInterval is reached, Logger will call flush() to send logged messages to different log targets, such as file, email, or database, with the help of the $dispatcher.

## Public Properties

Hide inherited properties

Property | Type | Description | Defined By
--- | --- | --- | ---
$behaviors | yii\base\Behavior[] | List of behaviors attached to this component. | yii\base\Component
$dbEventNames | array | Of event names used to get statistical results of DB queries. | yii\log\Logger
$dbProfiling | array | The first element indicates the number of SQL statements executed, and the second element the total time spent in SQL execution. | yii\log\Logger
$dispatcher | yii\log\Dispatcher | The message dispatcher. | yii\log\Logger
$elapsedTime | float | The total elapsed time in seconds for current request. | yii\log\Logger
$flushInterval | integer | How many messages should be logged before they are flushed from memory and sent to targets. | yii\log\Logger
$messages | array | Logged messages. | yii\log\Logger
$profiling | array | The profiling results. | yii\log\Logger
$profilingAware | boolean | Whether the profiling-aware mode should be switched on. | yii\log\Logger
$traceLevel | integer | How much call stack information (file name and line number) should be logged for each message. | yii\log\Logger

## Public Methods

Hide inherited methods

Method | Description | Defined By
--- | --- | ---
__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
__construct() | Constructor. | yii\base\BaseObject
__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
calculateTimings() | Calculates the elapsed time for the given log messages. | yii\log\Logger
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() | 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
flush() | Flushes log messages from memory to targets. | yii\log\Logger
getBehavior() | Returns the named behavior object. | yii\base\Component
getBehaviors() | Returns all behaviors attached to this component. | yii\base\Component
getDbProfiling() | Returns the statistical results of DB queries. | yii\log\Logger
getElapsedTime() | Returns the total elapsed time since the start of the current request. | yii\log\Logger
getLevelName() | Returns the text display of the specified level. | yii\log\Logger
getProfiling() | Returns the profiling results. | yii\log\Logger
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 logger by registering flush() as a shutdown function. | yii\log\Logger
log() | Logs a message with the given type and category. | yii\log\Logger
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

## Constants

Hide inherited constants

Constant | Value | Description | Defined By
--- | --- | --- | ---
LEVEL_ERROR | 0x1 | Error message level. An error message is one that indicates the abnormal termination of the application and may require developer's handling. | yii\log\Logger
LEVEL_INFO | 0x4 | Informational message level. An informational message is one that includes certain information for developers to review. | yii\log\Logger
LEVEL_PROFILE | 0x40 | Profiling message level. This indicates the message is for profiling purpose. | yii\log\Logger
LEVEL_PROFILE_BEGIN | 0x50 | Profiling message level. This indicates the message is for profiling purpose. It marks the beginning of a profiling block. | yii\log\Logger
LEVEL_PROFILE_END | 0x60 | Profiling message level. This indicates the message is for profiling purpose. It marks the end of a profiling block. | yii\log\Logger
LEVEL_TRACE | 0x8 | Tracing message level. A tracing message is one that reveals the code execution flow. | yii\log\Logger
LEVEL_WARNING | 0x2 | Warning message level. A warning message is one that indicates some abnormal happens but the application is able to continue to run. Developers should pay attention to this message. | yii\log\Logger

## Property Details

Hide inherited properties

$dbEventNames public property (available since version 2.0.41)

Of event names used to get statistical results of DB queries.

public array $dbEventNames = [
'yii\db\Command::query',
'yii\db\Command::execute',
]
$dbProfiling public property

The first element indicates the number of SQL statements executed, and the second element the total time spent in SQL execution.

public array $dbProfiling = null
$dispatcher public property

The message dispatcher.

public yii\log\Dispatcher $dispatcher = null
$elapsedTime public property

The total elapsed time in seconds for current request.

public float $elapsedTime = null
$flushInterval public property

How many messages should be logged before they are flushed from memory and sent to targets. Defaults to 1000, meaning the flush() method will be invoked once every 1000 messages logged. Set this property to be 0 if you don't want to flush messages until the application terminates. This property mainly affects how much memory will be taken by the logged messages. A smaller value means less memory, but will increase the execution time due to the overhead of flush().

public integer $flushInterval = 1000
$messages public property

Logged messages. This property is managed by log() and flush(). Each log message is of the following structure:

    [
      [0] => message (mixed, can be a string or some complex data, such as an exception object)
      [1] => level (integer)
      [2] => category (string)
      [3] => timestamp (float, obtained by microtime(true))
      [4] => traces (array, debug backtrace, contains the application code call stacks)
      [5] => memory usage in bytes (int, obtained by memory_get_usage()), available since version 2.0.11.
    ]

public array $messages = []
$profiling public property

The profiling results. Each element is an array consisting of these elements: `info`, `category`, `timestamp`, `trace`, `level`, `duration`, `memory`, `memoryDiff`. The `memory` and `memoryDiff` values are available since version 2.0.11.

public array $profiling = null
$profilingAware public property (available since version 2.0.43)

Whether the profiling-aware mode should be switched on. If on, flush() makes sure that profiling blocks are flushed in pairs. In case that any dangling messages are detected these are kept for the next flush interval to find their pair. To prevent memory leaks, when number of dangling messages reaches flushInterval value, logger flushes them immediately and triggers a warning. Keep in mind that profiling-aware mode is more time and memory consuming.

public boolean $profilingAware = false
$traceLevel public property

How much call stack information (file name and line number) should be logged for each message. If it is greater than 0, at most that number of call stacks will be logged. Note that only application call stacks are counted.

public integer $traceLevel = 0

## Method Details

Hide inherited methods

__call() public method

Defined in: yii\base\Component::__call()

Calls the named method which is not a class method.

This method will check if any attached behavior has the named method and will execute it if available.

Do not call this method directly as it is a PHP magic method that will be implicitly called when an unknown method is being invoked.

public mixed __call ( $name, $params )
$name | string | The method name
$params | array | Method parameters
return | mixed | The method return value
throws | yii\base\UnknownMethodException | when calling unknown method

Source code

                    public function __call($name, $params)
    {
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $object) {
            if ($object->hasMethod($name)) {
                return call_user_func_array([$object, $name], $params);
            }
        }
        throw new UnknownMethodException('Calling unknown method: ' . get_class($this) . "::$name()");
    }

__clone() public method

Defined in: yii\base\Component::__clone()

This method is called after the object is created by cloning an existing one.

It removes all behaviors because they are attached to the old object.

public void __clone ( )

Source code

                    public function __clone()
    {
        $this->_events = [];
        $this->_eventWildcards = [];
        $this->_behaviors = null;
    }

__construct() public method

Defined in: yii\base\BaseObject::__construct()

Constructor.

The default implementation does two things:

- Initializes the object with the given configuration `$config`.
- Call init().

If this method is overridden in a child class, it is recommended that

- the last parameter of the constructor is a configuration array, like `$config` here.
- call the parent implementation at the end of the constructor.

public void __construct ( $config = [] )
$config | array | Name-value pairs that will be used to initialize the object properties

Source code

                    public function __construct($config = [])
    {
        if (!empty($config)) {
            Yii::configure($this, $config);
        }
        $this->init();
    }

__get() public method

Defined in: yii\base\Component::__get()

Returns the value of a component property.

This method will check in the following order and act accordingly:

- a property defined by a getter: return the getter result
- a property of a behavior: return the behavior property value

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing `$value = $component->property;`.

See also __set().

public mixed __get ( $name )
$name | string | The property name
return | mixed | The property value or the value of a behavior's property
throws | yii\base\UnknownPropertyException | if the property is not defined
throws | yii\base\InvalidCallException | if the property is write-only.

Source code

                    public function __get($name)
    {
        $getter = 'get' . $name;
        if (method_exists($this, $getter)) {
            // read property, e.g. getName()
            return $this->$getter();
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canGetProperty($name)) {
                return $behavior->$name;
            }
        }
        if (method_exists($this, 'set' . $name)) {
            throw new InvalidCallException('Getting write-only property: ' . get_class($this) . '::' . $name);
        }
        throw new UnknownPropertyException('Getting unknown property: ' . get_class($this) . '::' . $name);
    }

__isset() public method

Defined in: yii\base\Component::__isset()

Checks if a property is set, i.e. defined and not null.

This method will check in the following order and act accordingly:

- a property defined by a setter: return whether the property is set
- a property of a behavior: return whether the property is set
- return `false` for non existing properties

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing `isset($component->property)`.

See also https://www.php.net/manual/en/function.isset.php.

public boolean __isset ( $name )
$name | string | The property name or the event name
return | boolean | Whether the named property is set

Source code

                    public function __isset($name)
    {
        $getter = 'get' . $name;
        if (method_exists($this, $getter)) {
            return $this->$getter() !== null;
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canGetProperty($name)) {
                return $behavior->$name !== null;
            }
        }
        return false;
    }

__set() public method

Defined in: yii\base\Component::__set()

Sets the value of a component property.

This method will check in the following order and act accordingly:

- a property defined by a setter: set the property value
- an event in the format of "on xyz": attach the handler to the event "xyz"
- a behavior in the format of "as xyz": attach the behavior named as "xyz"
- a property of a behavior: set the behavior property value

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing `$component->property = $value;`.

See also __get().

public void __set ( $name, $value )
$name | string | The property name or the event name
$value | mixed | The property value
throws | yii\base\UnknownPropertyException | if the property is not defined
throws | yii\base\InvalidCallException | if the property is read-only.

Source code

                    public function __set($name, $value)
    {
        $setter = 'set' . $name;
        if (method_exists($this, $setter)) {
            // set property
            $this->$setter($value);
            return;
        } elseif (strncmp($name, 'on ', 3) === 0) {
            // on event: attach event handler
            $this->on(trim(substr($name, 3)), $value);
            return;
        } elseif (strncmp($name, 'as ', 3) === 0) {
            // as behavior: attach behavior
            $name = trim(substr($name, 3));
            $this->attachBehavior($name, $value instanceof Behavior ? $value : Yii::createObject($value));
            return;
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canSetProperty($name)) {
                $behavior->$name = $value;
                return;
            }
        }
        if (method_exists($this, 'get' . $name)) {
            throw new InvalidCallException('Setting read-only property: ' . get_class($this) . '::' . $name);
        }
        throw new UnknownPropertyException('Setting unknown property: ' . get_class($this) . '::' . $name);
    }

__unset() public method

Defined in: yii\base\Component::__unset()

Sets a component property to be null.

This method will check in the following order and act accordingly:

- a property defined by a setter: set the property value to be null
- a property of a behavior: set the property value to be null

Do not call this method directly as it is a PHP magic method that will be implicitly called when executing `unset($component->property)`.

See also https://www.php.net/manual/en/function.unset.php.

public void __unset ( $name )
$name | string | The property name
throws | yii\base\InvalidCallException | if the property is read only.

Source code

                    public function __unset($name)
    {
        $setter = 'set' . $name;
        if (method_exists($this, $setter)) {
            $this->$setter(null);
            return;
        }
        // behavior property
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $behavior) {
            if ($behavior->canSetProperty($name)) {
                $behavior->$name = null;
                return;
            }
        }
        throw new InvalidCallException('Unsetting an unknown or read-only property: ' . get_class($this) . '::' . $name);
    }

attachBehavior() public method

Defined in: yii\base\Component::attachBehavior()

Attaches a behavior to this component.

This method will create the behavior object based on the given configuration. After that, the behavior object will be attached to this component by calling the yii\base\Behavior::attach() method.

See also detachBehavior().

public yii\base\Behavior attachBehavior ( $name, $behavior )
$name | string | The name of the behavior.

$behavior

string|array|yii\base\Behavior

The behavior configuration. This can be one of the following:

- a yii\base\Behavior object
- a string specifying the behavior class
- an object configuration array that will be passed to Yii::createObject() to create the behavior object.

return | yii\base\Behavior | The behavior object

Source code

                    public function attachBehavior($name, $behavior)
    {
        $this->ensureBehaviors();
        return $this->attachBehaviorInternal($name, $behavior);
    }

attachBehaviors() public method

Defined in: yii\base\Component::attachBehaviors()

Attaches a list of behaviors to the component.

Each behavior is indexed by its name and should be a yii\base\Behavior object, a string specifying the behavior class, or an configuration array for creating the behavior.

See also attachBehavior().

public void attachBehaviors ( $behaviors )
$behaviors | array | List of behaviors to be attached to the component

Source code

                    public function attachBehaviors($behaviors)
    {
        $this->ensureBehaviors();
        foreach ($behaviors as $name => $behavior) {
            $this->attachBehaviorInternal($name, $behavior);
        }
    }

behaviors() public method

Defined in: yii\base\Component::behaviors()

Returns a list of behaviors that this component should behave as.

Child classes may override this method to specify the behaviors they want to behave as.

The return value of this method should be an array of behavior objects or configurations indexed by behavior names. A behavior configuration can be either a string specifying the behavior class or an array of the following structure:

    'behaviorName' => [
        'class' => 'BehaviorClass',
        'property1' => 'value1',
        'property2' => 'value2',
    ]

Note that a behavior class must extend from yii\base\Behavior. Behaviors can be attached using a name or anonymously. When a name is used as the array key, using this name, the behavior can later be retrieved using getBehavior() or be detached using detachBehavior(). Anonymous behaviors can not be retrieved or detached.

Behaviors declared in this method will be attached to the component automatically (on demand).

public array behaviors ( )
return | array | The behavior configurations.

Source code

                    public function behaviors()
    {
        return [];
    }

calculateTimings() public method

Calculates the elapsed time for the given log messages.

public array calculateTimings ( $messages )
$messages | array | The log messages obtained from profiling
return | array | Timings. Each element is an array consisting of these elements: `info`, `category`, `timestamp`, `trace`, `level`, `duration`, `memory`, `memoryDiff`. The `memory` and `memoryDiff` values are available since version 2.0.11.

Source code

                    public function calculateTimings($messages)
    {
        $timings = [];
        $stack = [];
        foreach ($messages as $i => $log) {
            list($token, $level, $category, $timestamp, $traces) = $log;
            $memory = isset($log[5]) ? $log[5] : 0;
            $log[6] = $i;
            $hash = md5(json_encode($token));
            if ($level == self::LEVEL_PROFILE_BEGIN) {
                $stack[$hash] = $log;
            } elseif ($level == self::LEVEL_PROFILE_END) {
                if (isset($stack[$hash])) {
                    $timings[$stack[$hash][6]] = [
                        'info' => $stack[$hash][0],
                        'category' => $stack[$hash][2],
                        'timestamp' => $stack[$hash][3],
                        'trace' => $stack[$hash][4],
                        'level' => count($stack) - 1,
                        'duration' => $timestamp - $stack[$hash][3],
                        'memory' => $memory,
                        'memoryDiff' => $memory - (isset($stack[$hash][5]) ? $stack[$hash][5] : 0),
                    ];
                    unset($stack[$hash]);
                }
            }
        }
        ksort($timings);
        return array_values($timings);
    }

canGetProperty() public method

Defined in: yii\base\Component::canGetProperty()

Returns a value indicating whether a property can be read.

A property can be read if:

- the class has a getter method associated with the specified name (in this case, property name is case-insensitive);
- the class has a member variable with the specified name (when `$checkVars` is true);
- an attached behavior has a readable property of the given name (when `$checkBehaviors` is true).

See also canSetProperty().

public boolean canGetProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name | string | The property name
$checkVars | boolean | Whether to treat member variables as properties
$checkBehaviors | boolean | Whether to treat behaviors' properties as properties of this component
return | boolean | Whether the property can be read

Source code

                    public function canGetProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        if (method_exists($this, 'get' . $name) || $checkVars && property_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->canGetProperty($name, $checkVars)) {
                    return true;
                }
            }
        }
        return false;
    }

canSetProperty() public method

Defined in: yii\base\Component::canSetProperty()

Returns a value indicating whether a property can be set.

A property can be written if:

- the class has a setter method associated with the specified name (in this case, property name is case-insensitive);
- the class has a member variable with the specified name (when `$checkVars` is true);
- an attached behavior has a writable property of the given name (when `$checkBehaviors` is true).

See also canGetProperty().

public boolean canSetProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name | string | The property name
$checkVars | boolean | Whether to treat member variables as properties
$checkBehaviors | boolean | Whether to treat behaviors' properties as properties of this component
return | boolean | Whether the property can be written

Source code

                    public function canSetProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        if (method_exists($this, 'set' . $name) || $checkVars && property_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->canSetProperty($name, $checkVars)) {
                    return true;
                }
            }
        }
        return false;
    }

className() public static method
Deprecated since 2.0.14. On PHP >=5.5, use `::class` instead.

Defined in: yii\base\BaseObject::className()

Returns the fully qualified name of this class.

public static string className ( )
return | string | The fully qualified name of this class.

Source code

                    public static function className()
    {
        return get_called_class();
    }

detachBehavior() public method

Defined in: yii\base\Component::detachBehavior()

Detaches a behavior from the component.

The behavior's yii\base\Behavior::detach() method will be invoked.

public yii\base\Behavior|null detachBehavior ( $name )
$name | string | The behavior's name.
return | yii\base\Behavior|null | The detached behavior. Null if the behavior does not exist.

Source code

                    public function detachBehavior($name)
    {
        $this->ensureBehaviors();
        if (isset($this->_behaviors[$name])) {
            $behavior = $this->_behaviors[$name];
            unset($this->_behaviors[$name]);
            $behavior->detach();
            return $behavior;
        }
        return null;
    }

detachBehaviors() public method

Defined in: yii\base\Component::detachBehaviors()

Detaches all behaviors from the component.

public void detachBehaviors ( )

Source code

                    public function detachBehaviors()
    {
        $this->ensureBehaviors();
        foreach ($this->_behaviors as $name => $behavior) {
            $this->detachBehavior($name);
        }
    }

ensureBehaviors() public method

Defined in: yii\base\Component::ensureBehaviors()

Makes sure that the behaviors declared in behaviors() are attached to this component.

public void ensureBehaviors ( )

Source code

                    public function ensureBehaviors()
    {
        if ($this->_behaviors === null) {
            $this->_behaviors = [];
            foreach ($this->behaviors() as $name => $behavior) {
                $this->attachBehaviorInternal($name, $behavior);
            }
        }
    }

flush() public method

Flushes log messages from memory to targets.

public void flush ( $final = false )
$final | boolean | Whether this is a final call during a request.

Source code

                    public function flush($final = false)
    {
        if ($this->profilingAware) {
            $keep = [];
            $messages = [];
            foreach ($this->messages as $index => $message) {
                if (is_int($index)) {
                    $messages[] = $message;
                } else {
                    if (strncmp($index, 'begin-', 6) === 0) {
                        $oppositeProfile = 'end-' . substr($index, 6);
                    } else {
                        $oppositeProfile = 'begin-' . substr($index, 4);
                    }
                    if (array_key_exists($oppositeProfile, $this->messages)) {
                        $messages[] = $message;
                    } else {
                        $keep[$index] = $message;
                    }
                }
            }
            if ($this->flushInterval > 0 && count($keep) >= $this->flushInterval) {
                $this->messages = [];
                $this->log(
                    'Number of dangling profiling block messages reached flushInterval value and therefore these were flushed. Please consider setting higher flushInterval value or making profiling blocks shorter.',
                    self::LEVEL_WARNING
                );
                $messages = array_merge($messages, array_values($keep));
            } else {
                $this->messages = $keep;
            }
        } else {
            $messages = $this->messages;
            $this->messages = [];
        }
        if ($this->dispatcher instanceof Dispatcher) {
            $this->dispatcher->dispatch($messages, $final);
        }
    }

getBehavior() public method

Defined in: yii\base\Component::getBehavior()

Returns the named behavior object.

public yii\base\Behavior|null getBehavior ( $name )
$name | string | The behavior name
return | yii\base\Behavior|null | The behavior object, or null if the behavior does not exist

Source code

                    public function getBehavior($name)
    {
        $this->ensureBehaviors();
        return isset($this->_behaviors[$name]) ? $this->_behaviors[$name] : null;
    }

getBehaviors() public method

Defined in: yii\base\Component::getBehaviors()

Returns all behaviors attached to this component.

public yii\base\Behavior[] getBehaviors ( )
return | yii\base\Behavior[] | List of behaviors attached to this component

Source code

                    public function getBehaviors()
    {
        $this->ensureBehaviors();
        return $this->_behaviors;
    }

getDbProfiling() public method

Returns the statistical results of DB queries.

The results returned include the number of SQL statements executed and the total time spent.

public array getDbProfiling ( )
return | array | The first element indicates the number of SQL statements executed, and the second element the total time spent in SQL execution.

Source code

                    public function getDbProfiling()
    {
        $timings = $this->getProfiling($this->dbEventNames);
        $count = count($timings);
        $time = 0;
        foreach ($timings as $timing) {
            $time += $timing['duration'];
        }
        return [$count, $time];
    }

getElapsedTime() public method

Returns the total elapsed time since the start of the current request.

This method calculates the difference between now and the timestamp defined by constant `YII_BEGIN_TIME` which is evaluated at the beginning of yii\BaseYii class file.

public float getElapsedTime ( )
return | float | The total elapsed time in seconds for current request.

Source code

                    public function getElapsedTime()
    {
        return microtime(true) - YII_BEGIN_TIME;
    }

getLevelName() public static method

Returns the text display of the specified level.

public static string getLevelName ( $level )
$level | integer | The message level, e.g. LEVEL_ERROR, LEVEL_WARNING.
return | string | The text display of the level

Source code

                    public static function getLevelName($level)
    {
        static $levels = [
            self::LEVEL_ERROR => 'error',
            self::LEVEL_WARNING => 'warning',
            self::LEVEL_INFO => 'info',
            self::LEVEL_TRACE => 'trace',
            self::LEVEL_PROFILE_BEGIN => 'profile begin',
            self::LEVEL_PROFILE_END => 'profile end',
            self::LEVEL_PROFILE => 'profile',
        ];
        return isset($levels[$level]) ? $levels[$level] : 'unknown';
    }

getProfiling() public method

Returns the profiling results.

By default, all profiling results will be returned. You may provide `$categories` and `$excludeCategories` as parameters to retrieve the results that you are interested in.

public array getProfiling ( $categories = [], $excludeCategories = [] )
$categories | array | List of categories that you are interested in. You can use an asterisk at the end of a category to do a prefix match. For example, 'yii\db*' will match categories starting with 'yii\db\', such as 'yii\db\Connection'.
$excludeCategories | array | List of categories that you want to exclude
return | array | The profiling results. Each element is an array consisting of these elements: `info`, `category`, `timestamp`, `trace`, `level`, `duration`, `memory`, `memoryDiff`. The `memory` and `memoryDiff` values are available since version 2.0.11.

Source code

                    public function getProfiling($categories = [], $excludeCategories = [])
    {
        $timings = $this->calculateTimings($this->messages);
        if (empty($categories) && empty($excludeCategories)) {
            return $timings;
        }
        foreach ($timings as $outerIndex => $outerTimingItem) {
            $currentIndex = $outerIndex;
            $matched = empty($categories);
            foreach ($categories as $category) {
                $prefix = rtrim($category, '*');
                if (
                    ($outerTimingItem['category'] === $category || $prefix !== $category)
                    && strpos($outerTimingItem['category'], $prefix) === 0
                ) {
                    $matched = true;
                    break;
                }
            }
            if ($matched) {
                foreach ($excludeCategories as $category) {
                    $prefix = rtrim($category, '*');
                    foreach ($timings as $innerIndex => $innerTimingItem) {
                        $currentIndex = $innerIndex;
                        if (
                            ($innerTimingItem['category'] === $category || $prefix !== $category)
                            && strpos($innerTimingItem['category'], $prefix) === 0
                        ) {
                            $matched = false;
                            break;
                        }
                    }
                }
            }
            if (!$matched) {
                unset($timings[$currentIndex]);
            }
        }
        return array_values($timings);
    }

hasEventHandlers() public method

Defined in: yii\base\Component::hasEventHandlers()

Returns a value indicating whether there is any handler attached to the named event.

public boolean hasEventHandlers ( $name )
$name | string | The event name
return | boolean | Whether there is any handler attached to the event.

Source code

                    public function hasEventHandlers($name)
    {
        $this->ensureBehaviors();
        if (!empty($this->_events[$name])) {
            return true;
        }
        foreach ($this->_eventWildcards as $wildcard => $handlers) {
            if (!empty($handlers) && StringHelper::matchWildcard($wildcard, $name)) {
                return true;
            }
        }
        return Event::hasHandlers($this, $name);
    }

hasMethod() public method

Defined in: yii\base\Component::hasMethod()

Returns a value indicating whether a method is defined.

A method is defined if:

- the class has a method with the specified name
- an attached behavior has a method with the given name (when `$checkBehaviors` is true).

public boolean hasMethod ( $name, $checkBehaviors = true )
$name | string | The property name
$checkBehaviors | boolean | Whether to treat behaviors' methods as methods of this component
return | boolean | Whether the method is defined

Source code

                    public function hasMethod($name, $checkBehaviors = true)
    {
        if (method_exists($this, $name)) {
            return true;
        } elseif ($checkBehaviors) {
            $this->ensureBehaviors();
            foreach ($this->_behaviors as $behavior) {
                if ($behavior->hasMethod($name)) {
                    return true;
                }
            }
        }
        return false;
    }

hasProperty() public method

Defined in: yii\base\Component::hasProperty()

Returns a value indicating whether a property is defined for this component.

A property is defined if:

- the class has a getter or setter method associated with the specified name (in this case, property name is case-insensitive);
- the class has a member variable with the specified name (when `$checkVars` is true);
- an attached behavior has a property of the given name (when `$checkBehaviors` is true).

See also:

- canGetProperty()
- canSetProperty()

public boolean hasProperty ( $name, $checkVars = true, $checkBehaviors = true )
$name | string | The property name
$checkVars | boolean | Whether to treat member variables as properties
$checkBehaviors | boolean | Whether to treat behaviors' properties as properties of this component
return | boolean | Whether the property is defined

Source code

                    public function hasProperty($name, $checkVars = true, $checkBehaviors = true)
    {
        return $this->canGetProperty($name, $checkVars, $checkBehaviors) || $this->canSetProperty($name, false, $checkBehaviors);
    }

init() public method

Initializes the logger by registering flush() as a shutdown function.

public void init ( )

Source code

                    public function init()
    {
        parent::init();
        register_shutdown_function(function () {
            // make regular flush before other shutdown functions, which allows session data collection and so on
            $this->flush();
            // make sure log entries written by shutdown functions are also flushed
            // ensure "flush()" is called last when there are multiple shutdown functions
            register_shutdown_function([$this, 'flush'], true);
        });
    }

log() public method

Logs a message with the given type and category.

If $traceLevel is greater than 0, additional call stack information about the application code will be logged as well.

public void log ( $message, $level, $category = 'application' )
$message | string|array | The message to be logged. This can be a simple string or a more complex data structure that will be handled by a log target.
$level | integer | The level of the message. This must be one of the following: `Logger::LEVEL_ERROR`, `Logger::LEVEL_WARNING`, `Logger::LEVEL_INFO`, `Logger::LEVEL_TRACE`, `Logger::LEVEL_PROFILE`, `Logger::LEVEL_PROFILE_BEGIN`, `Logger::LEVEL_PROFILE_END`.
$category | string | The category of the message.

Source code

                    public function log($message, $level, $category = 'application')
    {
        $time = microtime(true);
        $traces = [];
        if ($this->traceLevel > 0) {
            $count = 0;
            $ts = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
            array_pop($ts); // remove the last trace since it would be the entry script, not very useful
            foreach ($ts as $trace) {
                if (isset($trace['file'], $trace['line']) && strpos($trace['file'], YII2_PATH) !== 0) {
                    unset($trace['object'], $trace['args']);
                    $traces[] = $trace;
                    if (++$count >= $this->traceLevel) {
                        break;
                    }
                }
            }
        }
        $data = [$message, $level, $category, $time, $traces, memory_get_usage()];
        if ($this->profilingAware && in_array($level, [self::LEVEL_PROFILE_BEGIN, self::LEVEL_PROFILE_END])) {
            $this->messages[($level == self::LEVEL_PROFILE_BEGIN ? 'begin-' : 'end-') . md5(json_encode($message))] = $data;
        } else {
            $this->messages[] = $data;
        }
        if ($this->flushInterval > 0 && count($this->messages) >= $this->flushInterval) {
            $this->flush();
        }
    }

off() public method

Defined in: yii\base\Component::off()

Detaches an existing event handler from this component.

This method is the opposite of on().

Note: in case wildcard pattern is passed for event name, only the handlers registered with this wildcard will be removed, while handlers registered with plain names matching this wildcard will remain.

See also on().

public boolean off ( $name, $handler = null )
$name | string | Event name
$handler | callable|null | The event handler to be removed. If it is null, all handlers attached to the named event will be removed.
return | boolean | If a handler is found and detached

Source code

                    public function off($name, $handler = null)
    {
        $this->ensureBehaviors();
        if (empty($this->_events[$name]) && empty($this->_eventWildcards[$name])) {
            return false;
        }
        if ($handler === null) {
            unset($this->_events[$name], $this->_eventWildcards[$name]);
            return true;
        }
        $removed = false;
        // plain event names
        if (isset($this->_events[$name])) {
            foreach ($this->_events[$name] as $i => $event) {
                if ($event[0] === $handler) {
                    unset($this->_events[$name][$i]);
                    $removed = true;
                }
            }
            if ($removed) {
                $this->_events[$name] = array_values($this->_events[$name]);
                return true;
            }
        }
        // wildcard event names
        if (isset($this->_eventWildcards[$name])) {
            foreach ($this->_eventWildcards[$name] as $i => $event) {
                if ($event[0] === $handler) {
                    unset($this->_eventWildcards[$name][$i]);
                    $removed = true;
                }
            }
            if ($removed) {
                $this->_eventWildcards[$name] = array_values($this->_eventWildcards[$name]);
                // remove empty wildcards to save future redundant regex checks:
                if (empty($this->_eventWildcards[$name])) {
                    unset($this->_eventWildcards[$name]);
                }
            }
        }
        return $removed;
    }

on() public method

Defined in: yii\base\Component::on()

Attaches an event handler to an event.

The event handler must be a valid PHP callback. The following are some examples:

    function ($event) { ... }         // anonymous function
    [$object, 'handleClick']          // $object->handleClick()
    ['Page', 'handleClick']           // Page::handleClick()
    'handleClick'                     // global function handleClick()

The event handler must be defined with the following signature,

    function ($event)

where `$event` is an yii\base\Event object which includes parameters associated with the event.

Since 2.0.14 you can specify event name as a wildcard pattern:

    $component->on('event.group.*', function ($event) {
        Yii::trace($event->name . ' is triggered.');
    });

See also off().

public void on ( $name, $handler, $data = null, $append = true )
$name | string | The event name
$handler | callable | The event handler
$data | mixed | The data to be passed to the event handler when the event is triggered. When the event handler is invoked, this data can be accessed via yii\base\Event::$data.
$append | boolean | Whether to append new event handler to the end of the existing handler list. If false, the new handler will be inserted at the beginning of the existing handler list.

Source code

                    public function on($name, $handler, $data = null, $append = true)
    {
        $this->ensureBehaviors();
        if (strpos($name, '*') !== false) {
            if ($append || empty($this->_eventWildcards[$name])) {
                $this->_eventWildcards[$name][] = [$handler, $data];
            } else {
                array_unshift($this->_eventWildcards[$name], [$handler, $data]);
            }
            return;
        }
        if ($append || empty($this->_events[$name])) {
            $this->_events[$name][] = [$handler, $data];
        } else {
            array_unshift($this->_events[$name], [$handler, $data]);
        }
    }

trigger() public method

Defined in: yii\base\Component::trigger()

Triggers an event.

This method represents the happening of an event. It invokes all attached handlers for the event including class-level handlers.

public void trigger ( $name, yii\base\Event $event = null )
$name | string | The event name
$event | yii\base\Event|null | The event instance. If not set, a default yii\base\Event object will be created.

Source code

                    public function trigger($name, Event $event = null)
    {
        $this->ensureBehaviors();
        $eventHandlers = [];
        foreach ($this->_eventWildcards as $wildcard => $handlers) {
            if (StringHelper::matchWildcard($wildcard, $name)) {
                $eventHandlers[] = $handlers;
            }
        }
        if (!empty($this->_events[$name])) {
            $eventHandlers[] = $this->_events[$name];
        }
        if (!empty($eventHandlers)) {
            $eventHandlers = call_user_func_array('array_merge', $eventHandlers);
            if ($event === null) {
                $event = new Event();
            }
            if ($event->sender === null) {
                $event->sender = $this;
            }
            $event->handled = false;
            $event->name = $name;
            foreach ($eventHandlers as $handler) {
                $event->data = $handler[1];
                call_user_func($handler[0], $event);
                // stop further handling if the event is handled
                if ($event->handled) {
                    return;
                }
            }
        }
        // invoke class-level attached handlers
        Event::trigger($this, $name, $event);
    }