dot-log
, (*1)
, (*2)
, (*3)
, (*4)
Adding The Config Provider
- Enter config/config.php
- If there is no entry for the config provider below, add it:
\Dot\Log\ConfigProvider::class
- Make sure it is added before with the Application-Specific components, eg.:
\Frontend\App\ConfigProvider.php, \Admin\App\ConfigProvider::class, MyProject\ConfigProvider::class , etc.
- Open the
Dot\Log\ConfigProvider
- In the dependencies section you will see an abstract factory (
LoggerAbstractServiceFactory::class)
- This class responds to "selectors" instead of class names
Instead of requesting the
Dot\Log\Logger::class from the container, dot-log.my_logger should be requested
Configuring the writer(s)
Loggers must have at least one writer., (*5)
A writer is an object that inherits from Dot\Log\Writer\AbstractWriter. A writer's responsibility is to record log data to a storage backend., (*6)
Writing to a file (stream)
It is possible separate logs into multiple files using writers and filters.
For example warnings.log, errors.log, all_messages.log., (*7)
The following is the simplest example to write all log messages to /log/dk.log, (*8)
return [
'dot_log' => [
'loggers' => [
'my_logger' => [
'writers' => [
'FileWriter' => [
'name' => 'FileWriter',
'priority' => \Dot\Log\Manager\Logger::ALERT, // this is equal to 1
'options' => [
'stream' => __DIR__ . '/../../log/dk.log',
],
],
],
]
],
],
];
- The
FileWriter key is optional, otherwise the writers array would be enumerative instead of associative.
- The writer name key is a developer-provided name for that writer, the writer name key is mandatory.
The writer priority key is not affecting the errors that are written, it is a way to organize writers., (*9)
The writer priority key is optional., (*10)
To write into a file the key stream must be present in the writer options array. This is required only if writing into streams/files., (*11)
Grouping log files by date
By default, logs will be written to the same file: log/dk.log.
Optionally, you can use date format specifiers wrapped between curly braces in your FileWriter's stream option, automatically grouping your logs by day, week, month, year etc.
Examples:, (*12)
-
log/dk-{Y}-{m}-{d}.log will write every day to a different file (eg: log/dk-2021-01-01.log)
-
log/dk-{Y}-{W}.log will write every week to a different file (eg: log/dk-2021-10.log)
The full list of format specifiers is available here., (*13)
Filtering log messages
As per PSR-3 document., (*14)
The log levels are: emergency (0), alert (1), critical (2), error (3), warn (4), notice (5), info (6), debug (7) (in order of priority/importance), (*15)
Although the plain Logger in Dot Log is not fully compatible with PSR-3, it provides a way to log all of these message types., (*16)
The following example has three file writers using filters:, (*17)
- First Example:
FileWriter - All messages are logged in /log/dk.log
- Second Example:
OnlyWarningsWriter - Only warnings are logged in /log/warnings.log
- Third Example:
WarningOrHigherWriter - All important messages (warnings or more critical) are logged in /log/important_messages.log
<?php
return [
'dot_log' => [
'loggers' => [
'my_logger' => [
'writers' => [
'FileWriter' => [
'name' => 'FileWriter',
'priority' => \Dot\Log\Manager\Logger::ALERT,
'options' => [
'stream' => __DIR__ . '/../../log/dk.log',
'filters' => [
'allMessages' => [
'name' => 'priority',
'options' => [
'operator' => '>=',
'priority' => \Dot\Log\Manager\Logger::EMERG,
]
],
],
],
],
// Only warnings
'OnlyWarningsWriter' => [
'name' => 'stream',
'priority' => \Dot\Log\Manager\Logger::ALERT,
'options' => [
'stream' => __DIR__ . '/../../log/warnings_only.log',
'filters' => [
'warningOnly' => [
'name' => 'priority',
'options' => [
'operator' => '==',
'priority' => \Dot\Log\Manager\Logger::WARN,
],
],
],
],
],
// Warnings and more important messages
'WarningOrHigherWriter' => [
'name' => 'stream',
'priority' => \Dot\Log\Manager\Logger::ALERT,
'options' => [
'stream' => __DIR__ . '/../../log/important_messages.log',
'filters' => [
'importantMessages' => [
'name' => 'priority',
'options' => [
// note, the smaller the priority, the more important is the message
// 0 - emergency, 1 - alert, 2- error, 3 - warn. .etc
'operator' => '<=',
'priority' => \Dot\Log\Manager\Logger::WARN,
],
],
],
],
],
],
],
],
],
];
As in the writer configuration, the developer can optionally use keys for associating the filters with a name., (*18)
IMPORTANT NOTE: the operator for more important messages is <=, this is because the number representation is smaller for a more important message type., (*19)
The filter added on the first writer is equal to not setting a filter, but it was been added to illustrate how to explicitly allow all messages., (*20)
It was added opposite to the others just to demonstrate the other operator is also an option., (*21)
When using dot-log, the logged value is not limited to a string. Arrays can be logged as well., (*22)
For a better readability, these arrays can be serialized., (*23)
Dot Log provides String formatting and JSON formatting., (*24)
The formatter accepts following parameters:, (*25)
name - the formatter class (it must implement Dot\Log\Formatter\FormatterInterface)
options - options to pass to the formatter constructor if required, (*26)
The following formats the message as JSON data:, (*27)
'formatter' => [
'name' => \Dot\Log\Manager\Formatter\Json::class,
],
- The log is used through dot-log
- The logger name is my_logger
- Writes to file: log/dk.log
- Explicitly allows all the messages to be written
- Formats the messages as JSON
<?php
return [
'dot_log' => [
'loggers' => [
'my_logger' => [
'writers' => [
'FileWriter' => [
'name' => 'FileWriter',
'priority' => \Dot\Log\Manager\Logger::ALERT,
'options' => [
'stream' => __DIR__ . '/../../log/dk.log',
// explicitly log all messages
'filters' => [
'allMessages' => [
'name' => 'priority',
'options' => [
'operator' => '>=',
'priority' => \Dot\Log\Manager\Logger::EMERG,
],
],
],
'formatter' => [
'name' => \Dot\Log\Manager\Formatter\Json::class,
],
],
],
],
],
],
],
];
Usage
Basic usage of the logger is illustrated below., (*28)
The messages are written to see which logs are written and which are not written., (*29)
use Dot\Log\Manager\Logger;
..., (*30)
$logger = $container->get('dot-log.my_logger');
/** @var Logger $logger */
$logger->emerg('0 EMERG');
$logger->alert('1 ALERT');
$logger->crit('2 CRITICAL');
$logger->err('3 ERR');
$logger->warn('4 WARN');
$logger->notice('5 NOTICE');
$logger->info('6 INF');
$logger->debug('7 debug');
$logger->log(Logger::NOTICE, 'NOTICE from log()');
Extracted from this article, (*31)
Wallogit.com
