Laravel Logging

Introduction
To help you learn more about what’s happening within your application, Laravel provides robust logging services that allow you to log messages to files, the system error log, and even to Slack to notify your entire team.

Under the hood, Laravel utilizes the Monolog library, which provides support for a variety of powerful log handlers. Laravel makes it a cinch to configure these handlers, allowing you to mix and match them to customize your application’s log handling.
あーーーーーーーlaravelもslack通知できるんだ！！！

Configuring The Channel Name
By default, Monolog is instantiated with a “channel name” that matches the current environment, such as production or local. To change this value, add a name option to your channel’s configuration:

'stack' => [
    'driver' => 'stack',
    'name' => 'channel-name',
    'channels' => ['single', 'slack'],
],

Available Channel Drivers
Name Description
stack A wrapper to facilitate creating “multi-channel” channels
single A single file or path based logger channel (StreamHandler)
daily A RotatingFileHandler based Monolog driver which rotates daily
slack A SlackWebhookHandler based Monolog driver
syslog A SyslogHandler based Monolog driver
errorlog A ErrorLogHandler based Monolog driver
monolog A Monolog factory driver that may use any supported Monolog handler
custom A driver that calls a specified factory to create a channel

Configuring The Slack Channel
The slack channel requires a url configuration option. This URL should match a URL for an incoming webhook that you have configured for your Slack team.

Building Log Stacks
As previously mentioned, the stack driver allows you to combine multiple channels into a single log channel. To illustrate how to use log stacks, let’s take a look at an example configuration that you might see in a production application:

'channels' => [
    'stack' => [
        'driver' => 'stack',
        'channels' => ['syslog', 'slack'],
    ],

    'syslog' => [
        'driver' => 'syslog',
        'level' => 'debug',
    ],

    'slack' => [
        'driver' => 'slack',
        'url' => env('LOG_SLACK_WEBHOOK_URL'),
        'username' => 'Laravel Log',
        'emoji' => ':boom:',
        'level' => 'critical',
    ],
],

ドライバーで指定して書いていくんだ。

Let’s dissect this configuration. First, notice our stack channel aggregates two other channels via its channels option: syslog and slack. So, when logging messages, both of these channels will have the opportunity to log the message.

Log Levels
Take note of the level configuration option present on the syslog and slack channel configurations in the example above. This option determines the minimum “level” a message must be in order to be logged by the channel. Monolog, which powers Laravel’s logging services, offers all of the log levels defined in the RFC 5424 specification: emergency, alert, critical, error, warning, notice, info, and debug.

So, imagine we log a message using the debug method:

Writing Log Messages
You may write information to the logs using the Log facade. As previously mentioned, the logger provides the eight logging levels defined in the RFC 5424 specification: emergency, alert, critical, error, warning, notice, info and debug:

Log::emergency($message);
Log::alert($message);
Log::critical($message);
Log::error($message);
Log::warning($message);
Log::notice($message);
Log::info($message);
Log::debug($message);

So, you may call any of these methods to log a message for the corresponding level. By default, the message will be written to the default log channel as configured by your config/logging.php configuration file:

namespace App\Http\Controllers;

use App\User;
use Illuminate\Support\Facades\Log;
use App\Http\Controllers\Controller;

class UserController extends Controller
{
    /**
     * Show the profile for the given user.
     *
     * @param  int  $id
     * @return Response
     */
    public function showProfile($id)
    {
        Log::info('Showing user profile for user: '.$id);

        return view('user.profile', ['user' => User::findOrFail($id)]);
    }
}

Contextual Information
An array of contextual data may also be passed to the log methods. This contextual data will be formatted and displayed with the log message:

Log::info(‘User failed to login.’, [‘id’ => $user->id]);
Writing To Specific Channels
Sometimes you may wish to log a message to a channel other than your application’s default channel. You may use the channel method on the Log facade to retrieve and log to any channel defined in your configuration file:

Log::channel(‘slack’)->info(‘Something happened!’);
If you would like to create an on-demand logging stack consisting of multiple channels, you may use the stack method:

Log::stack([‘single’, ‘slack’])->info(‘Something happened!’);
Advanced Monolog Channel Customization
Customizing Monolog For Channels
Sometimes you may need complete control over how Monolog is configured for an existing channel. For example, you may want to configure a custom Monolog FormatterInterface implementation for a given channel’s handlers.

To get started, define a tap array on the channel’s configuration. The tap array should contain a list of classes that should have an opportunity to customize (or “tap” into) the Monolog instance after it is created:

'single' => [
    'driver' => 'single',
    'tap' => [App\Logging\CustomizeFormatter::class],
    'path' => storage_path('logs/laravel.log'),
    'level' => 'debug',
],

Once you have configured the custom channel, you’re ready to define the class that will create your Monolog instance. This class only needs a single method: __invoke, which should return the Monolog instance:

namespace App\Logging;
use Monolog\Logger;

class CreateCustomLogger
{
    /**
     * Create a custom Monolog instance.
     *
     * @param  array  $config
     * @return \Monolog\Logger
     */
    public function __invoke(array $config)
    {
        return new Logger(...);
    }
}