php使用inotify扩展监控文件或目录的变化
一、安装inotify扩展
1、下载inotify扩展源码
https://pecl.php.net/package/inotify
对于php7以上版本，请下载 inotify-2.0.0.tgz。
2、编译安装
tar xf inotify-2.0.0.tgz cd inotify-2.0.0 /data/nmp/php/bin/phpize ./configure --with-php-config=/data/nmp/php/bin/php-config make && make install
3、修改php.ini，添加
extension = inotify.so
二、使用inotify进行文件监控
php的inotify扩展提供了监控文件或目录的功能，可以用来实现，服务的热更新，或安全监控。
inotify一共提供了5个函数：
1、inotify_init() 用于初始化一个实例，返回的是一个 stream 资源对象，可以被标准stream函数使用，如stream_set_blocking()。
2、inotify_add_watch() 将一个文件或目录添加到监控列表中，如果存在，则替换。
3、inotify_read() 从 inotify 实例中读取事件，如果没有返回false，如果有，返回一个 inotify 事件数组。
4、inotify_queue_len() 返回队列中事件的个数，可以理解为系统把 inotify_add_watch 关注的事件一个个加入队列，通过 inotify_read() 读取事件。
5、inotify_rm_watch() 取消监控。
封装一个类，用来监控文件或目录。
<?php
class InotifyMonitor
{
//需要监控的事件
const MONITOR_EVENT = IN_MODIFY | IN_CREATE | IN_DELETE | IN_DELETE_SELF | IN_CLOSE_WRITE;
//事件掩码
const EVENT_MASK = [
IN_ACCESS => 'File was accessed (read)',
IN_MODIFY => 'File was modified',
IN_ATTRIB => 'Metadata changed',
IN_CLOSE_WRITE => 'File opened for writing was closed',
IN_CLOSE_NOWRITE => 'File not opened for writing was closed',
IN_OPEN => 'File was opened',
IN_MOVED_TO => 'File moved into watched directory',
IN_MOVED_FROM => 'File moved out of watched directory',
IN_CREATE => 'File or directory created in watched directory',
IN_DELETE => 'File or directory deleted in watched directory',
IN_DELETE_SELF => 'Watched file or directory was deleted',
IN_MOVE_SELF => 'Watch file or directory was moved',
IN_CLOSE => 'Equals to IN_CLOSE_WRITE | IN_CLOSE_NOWRITE',
IN_MOVE => 'Equals to IN_MOVED_FROM | IN_MOVED_TO',
IN_ALL_EVENTS => 'Bitmask of all the above constants',
IN_UNMOUNT => 'File system containing watched object was unmounted',
IN_Q_OVERFLOW => 'Event queue overflowed (wd is -1 for this event)',
IN_IGNORED => 'Watch was removed (explicitly by inotify_rm_watch() or because file was removed or filesystem unmounted',
IN_ISDIR => 'Subject of this event is a directory',
IN_ONLYDIR => 'Only watch pathname if it is a directory',
IN_DONT_FOLLOW => 'Do not dereference pathname if it is a symlink',
IN_MASK_ADD => 'Add events to watch mask for this pathname if it already exists',
IN_ONESHOT => 'Monitor pathname for one event, then remove from watch list.',
1073741840 => 'High-bit: File not opened for writing was closed',
1073741856 => 'High-bit: File was opened',
1073742080 => 'High-bit: File or directory created in watched directory',
1073742336 => 'High-bit: File or directory deleted in watched directory',
];
//用于保存inotify_init返回的资源
public $fds = [];
//用于保存监控的文件路径
public $paths = [];
//用于保存inotify_add_watch返回的监控描述符
public $wds = [];
//超时时间
public $timeout = 3;
/**
* $paths添加监控的路径数组，可以是目录或文件
*/
public function __construct($paths = [])
{
if (!empty($paths)) {
foreach ($paths as $path) {
if (file_exists($path)) {
if (is_dir($path)) {
$this->addDir($path);
} else {
$this->addFile($path);
}
}
}
}
}
public function __destruct()
{
if (!empty($this->fds)) {
foreach ($this->fds as $fd) {
fclose($fd);
}
}
}
/**
* 添加文件监控
*/
public function addFile($file)
{
$file = realpath($file);
$fd = inotify_init();
$fid = (int)$fd;
//保存inotify资源
$this->fds[$fid] = $fd;
//设置为非阻塞模式
stream_set_blocking($this->fds[$fid], 0);
//保存文件路径
$this->paths[$fid] = $file;
//保存监控描述符
$this->wds[$fid] = inotify_add_watch($this->fds[$fid], $file, self::MONITOR_EVENT);
}
/**
* 添加目录监控
*/
public function addDir($dir)
{
$dir = realpath($dir);
if ($dh = opendir($dir)) {
//将目录加入监控中
$fd = inotify_init();
//一般文件的资源描述符是一个整形，可以用来当索引
$fid = (int)$fd;
$this->fds[$fid] = $fd;
stream_set_blocking($this->fds[$fid], 0);
$this->paths[$fid] = $dir;
$this->wds[$fid] = inotify_add_watch($this->fds[$fid], $dir, self::MONITOR_EVENT);
//遍历目录下文件
while (($file = readdir($dh)) !== false) {
if ($file == '.' || $file == '..') {
continue;
}
$file = $dir . DIRECTORY_SEPARATOR . $file;
if (is_dir($file)) {
$this->addDir($file);
}
}
closedir($dh);
}
}
/**
* 移除监控
*/
public function remove($fid)
{
unset($this->paths[$fid]);
fclose($this->fds[$fid]);
unset($this->fds[$fid]);
}
/**
* 运行监控
*/
public function run()
{
while (true) {
$reads = $this->fds;
$write = [];
$except = [];
if (stream_select($reads, $write, $except, $this->timeout) > 0) {
if (!empty($reads)) {
foreach ($reads as $read) {
//从可读流中读取数据
$events = inotify_read($read);
//资源描述符，整形
$fid = (int)$read;
//获取inotify实例的路径
$path = $this->paths[$fid];
foreach ($events as $event) {
$file = $path . DIRECTORY_SEPARATOR . $event['name'];
switch ($event['mask']) {
case IN_CREATE:
case 1073742080:
if (is_dir($file)) {
echo 'add ...', PHP_EOL;
echo 'fid : ', $fid, PHP_EOL;
$this->addDir($file);
}
break;
case IN_DELETE_SELF:
if (is_dir($file)) {
echo 'remove ...', PHP_EOL;
echo 'fid : ', $fid, PHP_EOL;
$this->remove($fid);
$key = array_search($read, $reads);
unset($reads[$key]);
}
break;
}
echo $event['name'], ' --- ', self::EVENT_MASK[$event['mask']], PHP_EOL;
}
}
}
} else {
echo '------------------', PHP_EOL;
echo '当前监控的路径列表', PHP_EOL;
print_r($this->paths);
echo '------------------', PHP_EOL;
}
}
}
}
(new InotifyMonitor(['./inotify.data']))->run();
