24.2. Writers

A Writer is an object that inherits from Zend_Log_Writer_Abstract. A Writer's responsibility is to record log data to a storage backend.

24.2.1. Writing to Streams

Zend_Log_Writer_Stream sends log data to a PHP stream.

To write log data to the PHP output buffer, use the URL php://output. Alternatively, you can may like to send log data directly to a stream like STDERR (php://stderr).

$writer = new Zend_Log_Writer_Stream('php://output');
$logger = new Zend_Log($writer);

$logger->info('Informational message');

To write data to a file, use one of the Filesystem URLs:

$writer = new Zend_Log_Writer_Stream('/path/to/logfile');
$logger = new Zend_Log($writer);

$logger->info('Informational message');

By default, the stream opens in the append mode ("a"). To open it with a different mode, the Zend_Log_Writer_Stream constructor accepts an optional second parameter for the mode.

The constructor of Zend_Log_Writer_Stream also accepts an existing stream resource:

$stream = @fopen('/path/to/logfile', 'a', false);
if (! $stream) {
    throw new Exception('Failed to open stream');

$writer = new Zend_Log_Writer_Stream($stream);
$logger = new Zend_Log($writer);

$logger->info('Informational message');

You cannot specify the mode for existing stream resources. Doing so causes a Zend_Log_Exception to be thrown.

24.2.2. Writing to Databases

Zend_Log_Writer_Db writes log information to a database table using Zend_Db. The constructor of Zend_Log_Writer_Db receives a Zend_Db_Adapter instance, a table name, and a mapping of database columns to event data items:

$params = array ('host'     => '',
                 'username' => 'malory',
                 'password' => '******',
                 'dbname'   => 'camelot');
$db = Zend_Db::factory('PDO_MYSQL', $params);

$columnMapping = array('lvl' => 'priority', 'msg' => 'message');
$writer = new Zend_Log_Writer_Db($db, 'log_table_name', $columnMapping);

$logger = new Zend_Log($writer);

$logger->info('Informational message');

The example above writes a single row of log data to the database table named log_table_name table. The database column named lvl receives the priority number and the column named msg receives the log message.

24.2.3. Stubbing Out the Writer

The Zend_Log_Writer_Null is a stub that does not write log data to anything. It is useful for disabling logging or stubbing out logging during tests:

$writer = new Zend_Log_Writer_Null;
$logger = new Zend_Log($writer);

// goes nowhere
$logger->info('Informational message');

24.2.4. Testing with the Mock

The Zend_Log_Writer_Mock is a very simple writer that records the raw data it receives in an array exposed as a public property.

$mock = new Zend_Log_Writer_Mock;
$logger = new Zend_Log($mock);

$logger->info('Informational message');


// Array
// (
//    [timestamp] => 2007-04-06T07:16:37-07:00
//    [message] => Informational message
//    [priority] => 6
//    [priorityName] => INFO
// )

To clear the events logged by the mock, simply set $mock->events = array().

24.2.5. Compositing Writers

There is no composite Writer object. However, a Log instance can write to any number of Writers. To do this, use the addWriter() method:

$writer1 = new Zend_Log_Writer_Stream('/path/to/first/logfile');
$writer2 = new Zend_Log_Writer_Stream('/path/to/second/logfile');

$logger = new Zend_Log();

// goes to both writers
$logger->info('Informational message');

    Поддержать сайт на родительском проекте КГБ