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PHP應用1.什么是守護過程
PHP應用守護進程是脫離于終端而且在后臺運行的進程.守護進程脫離于終端是為了避免進程在執行過程中的信息在任何終端上顯示而且進程也不會被任何終端所產生的終端信息所打斷.
PHP應用例如 apache, nginx, mysql 都是守護過程
PHP應用2.為什么開發守護過程
PHP應用很多程序以服務形式存在,他沒有終端或UI交互,它可能采納其他方式與其他程序交互,如TCP/UDP Socket, UNIX Socket, fifo.程序一旦啟動便進入后臺,直到滿足條件他便開始處理任務.
PHP應用3.何時采納守護進程開發應用程序
PHP應用以我當前的需求為例,我必要運行一個程序,然后監聽某端口,持續接受服務端發起的數據,然后對數據分析處理,再將結果寫入到數據庫中; 我采用ZeroMQ實現數據收發.
PHP應用如果我不采納守護進程方式開發該程序,程序一旦運行就會占用當前終端窗框,還有受到當前終端鍵盤輸入影響,有可能程序誤退出.
PHP應用4.守護進程的平安問題
PHP應用我們希望程序在非超等用戶運行,這樣一旦由于程序出現漏洞被駭客控制,攻擊者只能繼承運行權限,而無法獲得超等用戶權限.
PHP應用我們希望程序只能運行一個實例,不運行同事開啟兩個以上的程序,因為會呈現端口沖突等等問題.
PHP應用5.怎樣開發守護過程
PHP應用例 1. 守護過程例示
PHP應用
<?php
class ExampleWorker extends Worker {
#public function __construct(Logging $logger) {
# $this->logger = $logger;
#}
#protected $logger;
protected static $dbh;
public function __construct() {
}
public function run(){
$dbhost = '192.168.2.1'; // 數據庫服務器
$dbport = 3306;
$dbuser = 'www'; // 數據庫用戶名
$dbpass = 'qwer123'; // 數據庫暗碼
$dbname = 'example'; // 數據庫名
self::$dbh = new PDO("mysql:host=$dbhost;port=$dbport;dbname=$dbname", $dbuser, $dbpass, array(
/* PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES \'UTF8\'', */
PDO::MYSQL_ATTR_COMPRESS => true,
PDO::ATTR_PERSISTENT => true
)
);
}
protected function getInstance(){
return self::$dbh;
}
}
/* the collectable class implements machinery for Pool::collect */
class Fee extends Stackable {
public function __construct($msg) {
$trades = explode(",", $msg);
$this->data = $trades;
print_r($trades);
}
public function run() {
#$this->worker->logger->log("%s executing in Thread #%lu", __CLASS__, $this->worker->getThreadId() );
try {
$dbh = $this->worker->getInstance();
$insert = "INSERT INTO fee(ticket, login, volume, `status`) VALUES(:ticket, :login, :volume,'N')";
$sth = $dbh->prepare($insert);
$sth->bindValue(':ticket', $this->data[0]);
$sth->bindValue(':login', $this->data[1]);
$sth->bindValue(':volume', $this->data[2]);
$sth->execute();
$sth = null;
/* ...... */
$update = "UPDATE fee SET `status` = 'Y' WHERE ticket = :ticket and `status` = 'N'";
$sth = $dbh->prepare($update);
$sth->bindValue(':ticket', $this->data[0]);
$sth->execute();
//echo $sth->queryString;
//$dbh = null;
}
catch(PDOException $e) {
$error = sprintf("%s,%s\n", $mobile, $id );
file_put_contents("mobile_error.log", $error, FILE_APPEND);
}
}
}
class Example {
/* config */
const LISTEN = "tcp://192.168.2.15:5555";
const MAXCONN = 100;
const pidfile = __CLASS__;
const uid = 80;
const gid = 80;
protected $pool = NULL;
protected $zmq = NULL;
public function __construct() {
$this->pidfile = '/var/run/'.self::pidfile.'.pid';
}
private function daemon(){
if (file_exists($this->pidfile)) {
echo "The file $this->pidfile exists.\n";
exit();
}
$pid = pcntl_fork();
if ($pid == -1) {
die('could not fork');
} else if ($pid) {
// we are the parent
//pcntl_wait($status); //Protect against Zombie children
exit($pid);
} else {
// we are the child
file_put_contents($this->pidfile, getmypid());
posix_setuid(self::uid);
posix_setgid(self::gid);
return(getmypid());
}
}
private function start(){
$pid = $this->daemon();
$this->pool = new Pool(self::MAXCONN, \ExampleWorker::class, []);
$this->zmq = new ZMQSocket(new ZMQContext(), ZMQ::SOCKET_REP);
$this->zmq->bind(self::LISTEN);
/* Loop receiving and echoing back */
while ($message = $this->zmq->recv()) {
//print_r($message);
//if($trades){
$this->pool->submit(new Fee($message));
$this->zmq->send('TRUE');
//}else{
// $this->zmq->send('FALSE');
//}
}
$pool->shutdown();
}
private function stop(){
if (file_exists($this->pidfile)) {
$pid = file_get_contents($this->pidfile);
posix_kill($pid, 9);
unlink($this->pidfile);
}
}
private function help($proc){
printf("%s start | stop | help \n", $proc);
}
public function main($argv){
if(count($argv) < 2){
printf("please input help parameter\n");
exit();
}
if($argv[1] === 'stop'){
$this->stop();
}else if($argv[1] === 'start'){
$this->start();
}else{
$this->help($argv[0]);
}
}
}
$cgse = new Example();
$cgse->main($argv);
PHP應用5.1. 程序啟動
PHP應用下面是法式啟動后進入后臺的代碼
PHP應用通過進程ID文件來判斷,當前進程狀態,如果進程ID文件存在表示程序在運行中,通過代碼file_exists($this->pidfile)實現,但而后進程被kill必要手工刪除該文件才能運行
PHP應用
private function daemon(){
if (file_exists($this->pidfile)) {
echo "The file $this->pidfile exists.\n";
exit();
}
$pid = pcntl_fork();
if ($pid == -1) {
die('could not fork');
} else if ($pid) {
// we are the parent
//pcntl_wait($status); //Protect against Zombie children
exit($pid);
} else {
// we are the child
file_put_contents($this->pidfile, getmypid());
posix_setuid(self::uid);
posix_setgid(self::gid);
return(getmypid());
}
}
PHP應用法式啟動后,父進程會推出,子進程會在后臺運行,子進程權限從root切換到指定用戶,同時將pid寫入進程ID文件.
PHP應用5.2. 法式停止
PHP應用法式停止,只需讀取pid文件,然后調用posix_kill($pid, 9); 最后將該文件刪除.
PHP利用
private function stop(){
if (file_exists($this->pidfile)) {
$pid = file_get_contents($this->pidfile);
posix_kill($pid, 9);
unlink($this->pidfile);
}
}
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