1<?php 2/** 3 * $Header$ 4 * $Horde: horde/lib/Log/composite.php,v 1.2 2000/06/28 21:36:13 jon Exp $ 5 * 6 * @version $Revision$ 7 * @package Log 8 */ 9 10/** 11 * The Log_composite:: class implements a Composite pattern which 12 * allows multiple Log implementations to receive the same events. 13 * 14 * @author Chuck Hagenbuch <chuck@horde.org> 15 * @author Jon Parise <jon@php.net> 16 * 17 * @since Horde 1.3 18 * @since Log 1.0 19 * @package Log 20 * 21 * @example composite.php Using the composite handler. 22 */ 23class Log_composite extends Log 24{ 25 /** 26 * Array holding all of the Log instances to which log events should be 27 * sent. 28 * 29 * @var array 30 * @access private 31 */ 32 var $_children = array(); 33 34 35 /** 36 * Constructs a new composite Log object. 37 * 38 * @param string $name This parameter is ignored. 39 * @param string $ident This parameter is ignored. 40 * @param array $conf This parameter is ignored. 41 * @param int $level This parameter is ignored. 42 * 43 * @access public 44 */ 45 public function __construct($name, $ident = '', $conf = array(), 46 $level = PEAR_LOG_DEBUG) 47 { 48 $this->_ident = $ident; 49 } 50 51 /** 52 * Opens all of the child instances. 53 * 54 * @return True if all of the child instances were successfully opened. 55 * 56 * @access public 57 */ 58 function open() 59 { 60 /* Attempt to open each of our children. */ 61 $this->_opened = true; 62 foreach ($this->_children as $child) { 63 $this->_opened &= $child->open(); 64 } 65 66 /* If all children were opened, return success. */ 67 return $this->_opened; 68 } 69 70 /** 71 * Closes all open child instances. 72 * 73 * @return True if all of the opened child instances were successfully 74 * closed. 75 * 76 * @access public 77 */ 78 function close() 79 { 80 /* If we haven't been opened, there's nothing more to do. */ 81 if (!$this->_opened) { 82 return true; 83 } 84 85 /* Attempt to close each of our children. */ 86 $closed = true; 87 foreach ($this->_children as $child) { 88 if ($child->_opened) { 89 $closed &= $child->close(); 90 } 91 } 92 93 /* Clear the opened state for consistency. */ 94 $this->_opened = false; 95 96 /* If all children were closed, return success. */ 97 return $closed; 98 } 99 100 /** 101 * Flushes all child instances. It is assumed that all of the children 102 * have been successfully opened. 103 * 104 * @return True if all of the child instances were successfully flushed. 105 * 106 * @access public 107 * @since Log 1.8.2 108 */ 109 function flush() 110 { 111 /* Attempt to flush each of our children. */ 112 $flushed = true; 113 foreach ($this->_children as $child) { 114 $flushed &= $child->flush(); 115 } 116 117 /* If all children were flushed, return success. */ 118 return $flushed; 119 } 120 121 /** 122 * Sends $message and $priority to each child of this composite. If the 123 * appropriate children aren't already open, they will be opened here. 124 * 125 * @param mixed $message String or object containing the message 126 * to log. 127 * @param string $priority (optional) The priority of the message. 128 * Valid values are: PEAR_LOG_EMERG, 129 * PEAR_LOG_ALERT, PEAR_LOG_CRIT, 130 * PEAR_LOG_ERR, PEAR_LOG_WARNING, 131 * PEAR_LOG_NOTICE, PEAR_LOG_INFO, and 132 * PEAR_LOG_DEBUG. 133 * 134 * @return boolean True if the entry is successfully logged. 135 * 136 * @access public 137 */ 138 function log($message, $priority = null) 139 { 140 /* If a priority hasn't been specified, use the default value. */ 141 if ($priority === null) { 142 $priority = $this->_priority; 143 } 144 145 /* 146 * Abort early if the priority is above the composite handler's 147 * maximum logging level. 148 * 149 * XXX: Consider whether or not introducing this change would break 150 * backwards compatibility. Some users may be expecting composite 151 * handlers to pass on all events to their children regardless of 152 * their own priority. 153 */ 154 #if (!$this->_isMasked($priority)) { 155 # return false; 156 #} 157 158 /* 159 * Iterate over all of our children. If a unopened child will respond 160 * to this log event, we attempt to open it immediately. The composite 161 * handler's opened state will be enabled as soon as the first child 162 * handler is successfully opened. 163 * 164 * We track an overall success state that indicates whether or not all 165 * of the relevant child handlers were opened and successfully logged 166 * the event. If one handler fails, we still attempt any remaining 167 * children, but we consider the overall result a failure. 168 */ 169 $success = true; 170 foreach ($this->_children as $child) { 171 /* If this child won't respond to this event, skip it. */ 172 if (!$child->_isMasked($priority)) { 173 continue; 174 } 175 176 /* If this child has yet to be opened, attempt to do so now. */ 177 if (!$child->_opened) { 178 $success &= $child->open(); 179 180 /* 181 * If we've successfully opened our first handler, the 182 * composite handler itself is considered to be opened. 183 */ 184 if (!$this->_opened && $success) { 185 $this->_opened = true; 186 } 187 } 188 189 /* Finally, attempt to log the message to the child handler. */ 190 if ($child->_opened) { 191 $success &= $child->log($message, $priority); 192 } 193 } 194 195 /* Notify the observers. */ 196 $this->_announce(array('priority' => $priority, 'message' => $message)); 197 198 /* Return success if all of the open children logged the event. */ 199 return $success; 200 } 201 202 /** 203 * Returns true if this is a composite. 204 * 205 * @return boolean True if this is a composite class. 206 * 207 * @access public 208 */ 209 function isComposite() 210 { 211 return true; 212 } 213 214 /** 215 * Sets this identification string for all of this composite's children. 216 * 217 * @param string $ident The new identification string. 218 * 219 * @access public 220 * @since Log 1.6.7 221 */ 222 function setIdent($ident) 223 { 224 /* Call our base class's setIdent() method. */ 225 parent::setIdent($ident); 226 227 /* ... and then call setIdent() on all of our children. */ 228 foreach ($this->_children as $child) { 229 $child->setIdent($ident); 230 } 231 } 232 233 /** 234 * Adds a Log instance to the list of children. 235 * 236 * @param object $child The Log instance to add. 237 * 238 * @return boolean True if the Log instance was successfully added. 239 * 240 * @access public 241 */ 242 function addChild(&$child) 243 { 244 /* Make sure this is a Log instance. */ 245 if (!is_a($child, 'Log')) { 246 return false; 247 } 248 249 $this->_children[$child->_id] = $child; 250 251 return true; 252 } 253 254 /** 255 * Removes a Log instance from the list of children. 256 * 257 * @param object $child The Log instance to remove. 258 * 259 * @return boolean True if the Log instance was successfully removed. 260 * 261 * @access public 262 */ 263 function removeChild($child) 264 { 265 if (!is_a($child, 'Log') || !isset($this->_children[$child->_id])) { 266 return false; 267 } 268 269 unset($this->_children[$child->_id]); 270 271 return true; 272 } 273 274} 275