common/logging/Logger.php

   1 <?php
   2 /**
   3  * Application logger. Puts daily logs in the server's temporary directory. Log level is set in
   4  * globals as $GLOBALS["log_level"] (this is customizable in the globals file).
   5
   6  * A *nix user can run the following command to see the logs:
   7  * <code>
   8  *     > tail -f /var/www/openemr/logs/2016_11_24_application.log
   9  *     2016-11-24 20:15:07 [TRACE] \common\database\Connector - Connecting with pooled mode
  10  *     2016-11-24 20:15:07 [TRACE] \common\database\Connector - Wiring up Doctrine entities
  11  *     2016-11-24 20:15:07 [TRACE] \common\database\Connector - Creating connection
  12  *     2016-11-24 20:15:07 [INFO] \some\other\Class - Some info message
  13  *     2016-11-24 20:18:01 [WARN] \some\other\Class - Some field is missing
  14  * </code>
  15  *
  16  * @note Error level logs will also be sent to Apache error log.
  17  *
  18  * @note Application logging is sparse at the moment (will be introduced w/ the modernization project).
  19  *
  20  * Copyright (C) 2016 Matthew Vita <matthewvita48@gmail.com>
  21  *
  22  * LICENSE: This program is free software; you can redistribute it and/or
  23  * modify it under the terms of the GNU General Public License
  24  * as published by the Free Software Foundation; either version 2
  25  * of the License, or (at your option) any later version.
  26  * This program is distributed in the hope that it will be useful,
  27  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  29  * GNU General Public License for more details.
  30  * You should have received a copy of the GNU General Public License
  31  * along with this program. If not, see <http://opensource.org/licenses/gpl-license.php>.
  32  *
  33  * @package OpenEMR
  34  * @author  Matthew Vita <matthewvita48@gmail.com>
  35  * @link    http://www.open-emr.org
  36  */
  37
  38 namespace OpenEMR\Common\Logging;
  39
  40 class Logger
  41 {
  42     /**
  43      * The class that is associated with a log entry.
  44      */
  45     private $classContext;
  46
  47     /**
  48      * The fully qualified log file path.
  49      */
  50     private $logFile;
  51
  52     /**
  53      * Default constructor. Only continues with instance creation
  54      * if logging is enabled.
  55      *
  56      * @param $classContext - provided when a class uses the logger.
  57      */
  58     public function __construct($classContext = "UnknownClassContext")
  59     {
  60         if (isset($GLOBALS["log_level"]) && $GLOBALS["log_level"] !== "OFF") {
  61             $this->classContext = $classContext;
  62             $this->determineLogFilePath();
  63         }
  64     }
  65
  66     /**
  67      * Sets the log file on the operating system's temporary directory. Format is:
  68      * [log area] + FILE_SEP + YYYY_MM_DD_application.log
  69      *
  70      * On *nix, the file will be stored in /home/current_user/openemr/ (if writable). On Windows, it will
  71      * be stored in C:\Users\current_user\openemr\ (if writable).
  72      */
  73     private function determineLogFilePath()
  74     {
  75         $fileName = date("Y_m_d") . "_application.log";
  76
  77         global $webserver_root;
  78         $currentDir = $webserver_root;
  79         $logDirName = 'logs';
  80         $combinedLogDir = $currentDir . DIRECTORY_SEPARATOR . $logDirName;
  81
  82         if (!is_dir($combinedLogDir)) {
  83             mkdir($combinedLogDir);
  84         }
  85
  86         if (is_writable($combinedLogDir)) {
  87             $this->logFile = $combinedLogDir . DIRECTORY_SEPARATOR . $fileName;
  88         } else {
  89             error_log('Can\'t write application log file to ' . $combinedLogDir);
  90         }
  91     }
  92
  93     /**
  94      * Determines if the log level is allowed by the log level in the global
  95      * configuration.
  96      *
  97      * Hierarchy/conditions:
  98      *     - TRACE (allows TRACE, DEBUG, INFO, WARN, ERROR)
  99      *     - DEBUG (allows DEBUG, INFO, WARN, ERROR)
 100      *     - INFO  (allows INFO, WARN, ERROR)
 101      *     - WARN  (allows WARN, ERROR)
 102      *     - ERROR (allows ERROR)
 103      *     - OFF   (no logs)
 104      *
 105      * @param $level the incoming log level
 106      * @return boolean that represents if log entry should be made
 107      */
 108     private function isLogLevelInDesiredHierarchy($level)
 109     {
 110         if (empty($GLOBALS["log_level"]) || $GLOBALS["log_level"] === "OFF") {
 111             return false;
 112         }
 113
 114         if ($GLOBALS["log_level"] === "TRACE") {
 115             return true;
 116         } else if ($GLOBALS["log_level"] === "DEBUG" && in_array($level, array("DEBUG", "INFO", "WARN", "ERROR"))) {
 117             return true;
 118         } else if ($GLOBALS["log_level"] === "INFO" && in_array($level, array("INFO", "WARN", "ERROR"))) {
 119             return true;
 120         } else if ($GLOBALS["log_level"] === "WARN" && in_array($level, array("WARN", "ERROR"))) {
 121             return true;
 122         } else if ($GLOBALS["log_level"] === "ERROR" && $level === "ERROR") {
 123             return true;
 124         } else {
 125             return false;
 126         }
 127     }
 128
 129     /**
 130      * Used for informational messages of the application.
 131      *
 132      * @param $message - the log message
 133      */
 134     public function info($message)
 135     {
 136         $this->log($message, "INFO");
 137     }
 138
 139     /**
 140      * Used by developers that wish to expose information that is
 141      * notable for developers.
 142      *
 143      * @param $message - the log message
 144      */
 145     public function debug($message)
 146     {
 147         $this->log($message, "DEBUG");
 148     }
 149
 150     /**
 151      * Used by developers that wish to expose information that is
 152      * notable for developers. Note this is more "noisy" than debug.
 153      *
 154      * @param $message - the log message
 155      */
 156     public function trace($message)
 157     {
 158         $this->log($message, "TRACE");
 159     }
 160
 161     /**
 162      * Used for in case of harmful conditions.
 163      *
 164      * @param $message - the log message
 165      */
 166     public function warn($message)
 167     {
 168         $this->log($message, "WARN");
 169     }
 170
 171     /**
 172      * Used for in case an error occurs and the application might continue running.
 173      *
 174      * @param $message - the log message
 175      */
 176     public function error($message)
 177     {
 178         $this->log($message, "ERROR");
 179     }
 180
 181     /**
 182      * Writes the entry to the log file. If the level is type "error", the message
 183      * will additionally go to the Apache error log.
 184      *
 185      * @param $message - the log message
 186      * @param $type - the log type
 187      */
 188     private function log($message, $type)
 189     {
 190         if ($this->isLogLevelInDesiredHierarchy($type) && !empty($this->logFile)) {
 191             $logEntry = date("Y-m-d H:i:s") . " [" . $type . "] " . $this->classContext . " - " . $message;
 192
 193             file_put_contents($this->logFile, $logEntry.PHP_EOL, FILE_APPEND | LOCK_EX);
 194
 195             if ($type === "ERROR") {
 196                 error_log($message);
 197             }
 198         }
 199     }
 200 }