Logger.php

<?php

/**
 * st-PHP-Logger - Simple PHP logging class. Log info, warning, error messages to log files.
 */

/**
 * @author  Drew D. Lenhart - snowytech
 * @since   May 29, 2016
 * @link    https://github.com/snowytech/st-php-logger
 * @source  https://raw.githubusercontent.com/dlenhart/st-php-logger/master/st-php-logger.php
 * @version 1.0.0
 */

class Logger {

    const DEBUG = 1;
    const INFO = 2;
    const WARNING = 3;
    const ERROR = 4;
    const NONE = 5;

    protected $level = 0;

    /**
     * $log_file - path and log file name
     * @var string
     */
    protected $log_file;

    /**
     * $file - file
     * @var string
     */
    protected $file;

    /**
     * $options - settable options - future use - passed through constructor
     * @var array
     */
    protected $options = array(
        'dateFormat' => 'd-M-Y H:i:s'
    );

    /**
     * Class constructor
     * @param string $log_file - path and filename of log
     * @param array $params
     */
    public function __construct($log_file = 'error.txt', $params = array()){
        $this->log_file = $log_file;
        $this->params = array_merge($this->options, $params);

        //Create log file if it doesn't exist.
        if(!file_exists($log_file)){
            fopen($log_file, 'w') or exit("Can't create $log_file!");
        }

        //Check permissions of file.
        if(!is_writable($log_file)){
            //throw exception if not writable
            throw new Exception("ERROR: Unable to write to file!", 1);
        }
    }

    /**
     * Info method (write info message)
     * @param string $message
     * @return void
     */
    public function info($message) {
        if($this->level <= self::INFO) {
            $this->writeLog($message, 'INFO');
        }
    }

    /**
     * Debug method (write debug message)
     * @param string $message
     * @return void
     */
    public function debug($message) {
        if($this->level <= self::DEBUG) {
            $this->writeLog($message, 'DEBUG');
        }
    }

    /**
     * Warning method (write warning message)
     * @param string $message
     * @return void
     */
    public function warning($message){
        if($this->level <= self::WARNING) {
            $this->writeLog($message, 'WARNING');
        }
    }

    /**
     * Error method (write error message)
     * @param string $message
     * @return void
     */
    public function error($message){
        if($this->level <= self::ERROR) {
            $this->writeLog($message, 'ERROR');
        }
    }

    /**
     * Write to log file
     * @param string $message
     * @param string $severity
     * @return void
     */
    public function writeLog($message, $severity) {
        // open log file
        if (!is_resource($this->file)) {
            $this->openLog();
        }
        // grab the url path ( for troubleshooting )
        $path = $_SERVER["SERVER_NAME"] . $_SERVER["REQUEST_URI"];

        //Grab time - based on timezone in php.ini
        $time = date($this->params['dateFormat']);

        // Write time, url, & message to end of file
        fwrite($this->file, "[$time] [$path] : [$severity] - $message" . PHP_EOL);
    }

    /**
     * Open log file
     * @return void
     */
    private function openLog(){
        $openFile = $this->log_file;
        // 'a' option = place pointer at end of file
        $this->file = fopen($openFile, 'a') or exit("Can't open $openFile!");
    }

    /**
     * Class destructor
     */
    public function __destruct(){
        if ($this->file) {
            fclose($this->file);
        }
    }

    /**
     * @return int
     */
    public function getLevel()
    {
        return $this->level;
    }

    /**
     * @param int $level
     */
    public function setLevel($level) {
        if(in_array($level, array(self::DEBUG, self::INFO, self::WARNING, self::ERROR, self::NONE))) {
            $this->level = $level;
        }
    }


}