Logging

PHP:
Logging

How to:

PHP comes with a built-in error logging function that’s easy to use. Just pop error_log() into your code to send a message to your server logs. You can also customize it to write to a specific file.

<?php
// Logging a simple info message
error_log("This is an info log entry.");

// Logging an error message
error_log("This is an error log entry.", 0);

// Logging to a specified file
file_put_contents('/path/to/your/custom.log', "A custom log entry.\n", FILE_APPEND);

// Using Monolog for structured logging
require 'vendor/autoload.php';
use Monolog\Logger;
use Monolog\Handler\StreamHandler;

// Create the logger
$logger = new Logger('name');
// Now add some handlers
$logger->pushHandler(new StreamHandler('/path/to/your/monolog.log', Logger::WARNING));

// You can now use your logger
$logger->warning('This is a warning log!');
$logger->error('This is an error log!');
?>

This will output your logs to either the server log or your specified file in plain text format.

Deep Dive:

Historically, PHP developers relied on error_log() function or the Apache/Nginx logs to catch issues, but that can be chaotic with the need to parse plain text files and no easy way to filter or sort them. Enter logging libraries like Monolog, which ushered in the era of structured logging in PHP. These solutions give you better control by offering multiple logging channels, severity levels, and formatted output (like JSON, which is a dream for parsing programmatically).

Alternatives to Monolog include Log4php, KLogger, and Apache’s Log4php. Implementation-wise, robust logging requires not just dumping data wherever, but considering things like log rotation, archival strategies, and integration with monitoring tools to truly be useful.

You should keep the PSR-3 Logger Interface in mind, which outlines a common interface for logging libraries, ensuring interoperability and a consistent way to access logging mechanisms.

PHP:Logging

How to:

Deep Dive:

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PHP:
Logging