Monolog - Logging for PHP 5.3
=============================

[![Build Status](https://secure.travis-ci.org/Seldaek/monolog.png)](http://travis-ci.org/Seldaek/monolog)

Usage
-----

```php
<?php

use Monolog\Logger;
use Monolog\Handler\StreamHandler;

// create a log channel
$log = new Logger('name');
$log->pushHandler(new StreamHandler('path/to/your.log', Logger::WARNING));

// add records to the log
$log->addWarning('Foo');
$log->addError('Bar');
```

Core Concepts
-------------

Every `Logger` instance has a channel (name) and a stack of handlers. Whenever
you add a record to the logger, it traverses the handler stack. Each handler
decides whether it handled fully the record, and if so, the propagation of the
record ends there.

This allow for flexible logging setups, for example having a `StreamHandler` at
the bottom of the stack that will log anything to disk, and on top of that add
a `MailHandler` that will send emails only when an error message is logged.
Handlers also have a `$bubble` property which defines whether they block the
record or not if they handled it. In this example, setting the `MailHandler`'s
`$bubble` argument to true means that all records will propagate to the
`StreamHandler`, even the errors that are handled by the `MailHandler`.

You can create many `Logger`s, each defining a channel (e.g.: db, request,
router, ..) and each of them combining various handlers, which can be shared
or not. The channel is reflected in the logs and allows you to easily see or
filter records.

Each Handler also has a Formatter, a default one with settings that make sense
will be created if you don't set one. The formatters normalize and format
incoming records so that they can be used by the handlers to output useful
information.

Custom severity levels are not available. Only the eight
[RFC 5424](http://tools.ietf.org/html/rfc5424) levels (debug, info, notice,
warning, error, critical, alert, emergency) are present for basic filtering
purposes, but for sorting and other use cases that would require
flexibility, you should add Processors to the Logger that can add extra
information (tags, user ip, ..) to the records before they are handled.

Log Levels
----------

Monolog supports all 8 logging levels defined in
[RFC 5424](http://tools.ietf.org/html/rfc5424), but unless you specifically
need syslog compatibility, it is advised to only use DEBUG, INFO, WARNING,
ERROR, CRITICAL, ALERT.

- **DEBUG** (100): Detailed debug information.

- **INFO** (200): Interesting events. Examples: User logs in, SQL logs.

- NOTICE (250): Normal but significant events.

- **WARNING** (300): Exceptional occurrences that are not errors. Examples:
  Use of deprecated APIs, poor use of an API, undesirable things that are not
  necessarily wrong.

- **ERROR** (400): Runtime errors that do not require immediate action but
  should typically be logged and monitored.

- **CRITICAL** (500): Critical conditions. Example: Application component
  unavailable, unexpected exception.

- **ALERT** (550): Action must be taken immediately. Example: Entire website
  down, database unavailable, etc. This should trigger the SMS alerts and wake
  you up.

- EMERGENCY (600): Emergency: system is unusable.

Docs
====

**See the `doc` directory for more detailed documentation.
The following is only a list of all parts that come with Monolog.**

Handlers
--------

- _StreamHandler_: Logs records into any PHP stream, use this for log files.
- _RotatingFileHandler_: Logs records to a file and creates one logfile per day.
  It will also delete files older than `$maxFiles`. You should use
  [logrotate](http://linuxcommand.org/man_pages/logrotate8.html) for high profile
  setups though, this is just meant as a quick and dirty solution.
- _FirePHPHandler_: Handler for [FirePHP](http://www.firephp.org/), providing
  inline `console` messages within [FireBug](http://getfirebug.com/).
- _ChromePHPHandler_: Handler for [ChromePHP](http://www.chromephp.com/), providing
  inline `console` messages within Chrome.
- _MongoDBHandler_: Handler to write records in MongoDB via a
  [Mongo](http://pecl.php.net/package/mongo) extension connection.
- _NativeMailHandler_: Sends emails using PHP's
  [`mail()`](http://php.net/manual/en/function.mail.php) function.
- _SwiftMailerHandler_: Sends emails using a [`Swift_Mailer`](http://swiftmailer.org/) instance.
- _SyslogHandler_: Logs records to the syslog.
- _GelfHandler_: Logs records to a [Graylog2](http://www.graylog2.org) server.
- _SocketHandler_: Logs records to [sockets](http://php.net/fsockopen), use this
  for UNIX and TCP sockets. See an [example](https://github.com/Seldaek/monolog/blob/master/doc/sockets.md).
- _AmqpHandler_: Logs records to an [amqp](http://www.amqp.org/) compatible
  server. Requires the [php-amqp](http://pecl.php.net/package/amqp) extension (1.0+).
- _CubeHandler_: Logs records to a [Cube](http://square.github.com/cube/) server.

Wrappers / Special Handlers
---------------------------

- _FingersCrossedHandler_: A very interesting wrapper. It takes a logger as
  parameter and will accumulate log records of all levels until a record
  exceeds the defined severity level. At which point it delivers all records,
  including those of lower severity, to the handler it wraps. This means that
  until an error actually happens you will not see anything in your logs, but
  when it happens you will have the full information, including debug and info
  records. This provides you with all the information you need, but only when
  you need it.
- _NullHandler_: Any record it can handle will be thrown away. This can be used
  to put on top of an existing handler stack to disable it temporarily.
- _BufferHandler_: This handler will buffer all the log records it receives
  until `close()` is called at which point it will call `handleBatch()` on the
  handler it wraps with all the log messages at once. This is very useful to
  send an email with all records at once for example instead of having one mail
  for every log record.
- _GroupHandler_: This handler groups other handlers. Every record received is
  sent to all the handlers it is configured with.
- _TestHandler_: Used for testing, it records everything that is sent to it and
  has accessors to read out the information.

Formatters
----------

- _LineFormatter_: Formats a log record into a one-line string.
- _NormalizerFormatter_: Normalizes objects/resources down to strings so a record can easily be serialized/encoded.
- _JsonFormatter_: Encodes a log record into json.
- _WildfireFormatter_: Used to format log records into the Wildfire/FirePHP protocol, only useful for the FirePHPHandler.
- _ChromePHPFormatter_: Used to format log records into the ChromePHP format, only useful for the ChromePHPHandler.
- _GelfFormatter_: Used to format log records into Gelf message instances, only useful for the GelfHandler.

Processors
----------

- _IntrospectionProcessor_: Adds the line/file/class/method from which the log call originated.
- _WebProcessor_: Adds the current request URI, request method and client IP to a log record.
- _MemoryUsageProcessor_: Adds the current memory usage to a log record.
- _MemoryPeakUsageProcessor_: Adds the peak memory usage to a log record.

About
=====

Requirements
------------

- Any flavor of PHP 5.3 should do
- [optional] PHPUnit 3.5+ to execute the test suite (phpunit --version)

Submitting bugs and feature requests
------------------------------------

Bugs and feature request are tracked on [GitHub](https://github.com/Seldaek/monolog/issues)

Author
------

Jordi Boggiano - <j.boggiano@seld.be> - <http://twitter.com/seldaek><br />
See also the list of [contributors](https://github.com/Seldaek/monolog/contributors) which participated in this project.

License
-------

Monolog is licensed under the MIT License - see the `LICENSE` file for details

Acknowledgements
----------------

This library is heavily inspired by Python's [Logbook](http://packages.python.org/Logbook/)
library, although most concepts have been adjusted to fit to the PHP world.
