相關筆記：
Beanstalkd消息/任務隊列
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Composer在Windows和Linux的安裝和使用
有關Beanstalkd的基本概念，編譯和yum的安裝方法已經在上述筆記中記錄了，今天練習下PHP使用Beanstalkd的過程，我選擇的是使用Pheanstalk類來連接Beanstalkd
1.使用Composer安裝Pheanstalk
composer require pda/pheanstalk2.實現代碼
php查看beanstalkd狀態腳本Status.php
<?php
/**
* Created by PhpStorm.
* User: jmsite.cn
* Date: 2019/1/21
* Time: 10:32
*/
require "../vendor/autoload.php";
use Pheanstalk\Pheanstalk;
$pheanstalk = new Pheanstalk('192.168.75.135',11300);
print_r($pheanstalk->stats());生產者代碼Producter.php
<?php
/**
* Created by PhpStorm.
* User: jmsite.cn
* Date: 2019/1/20
* Time: 16:30
*/
require "../vendor/autoload.php";
use Pheanstalk\Pheanstalk;
$pheanstalk = new Pheanstalk('192.168.75.135',11300);
for ($i=0;$i<50;$i++){
$data = array(
'key' => 'testkey'.$i,
'value' => 'testvalue',
'time' => time(),
);
$ret = $pheanstalk->putInTube('test-tube', json_encode($data), Pheanstalk::DEFAULT_PRIORITY, Pheanstalk::DEFAULT_DELAY, Pheanstalk::DEFAULT_TTR);
var_dump($ret);
}消費者代碼Consumer.php
<?php
/**
* Created by PhpStorm.
* User: jmsite.cn
* Date: 2019/1/20
* Time: 16:31
*/
set_time_limit(0);
ini_set('default_socket_timeout', 900);
require "../vendor/autoload.php";
use Pheanstalk\Pheanstalk;
$pheanstalk = new Pheanstalk('192.168.75.135',11300);
while (true){
$job = $pheanstalk
->watch('test-tube')
->ignore('default')
->reserve();
if ($job){
sleep(2);
echo $job->getData();
echo "\n";
$pheanstalk->delete($job);
}
}
打開命令行/終端窗口，執行生產者，會向tube寫入50條任務
PS E:\repository\work\beanstalk> php .\Producter.php
int(101)
int(102)
int(103)
int(104)
int(105)
int(106)
int(107)
int(108)
int(109)
int(110)
int(111)
int(112)
int(113)
int(114)
......由此可見，$pheanstalk->putInTube成功後返回的是job的id
查看狀態
PS E:\repository\work\beanstalk> php Status.php
Pheanstalk\Response\ArrayResponse Object
(
[_name:Pheanstalk\Response\ArrayResponse:private] => OK
[storage:ArrayObject:private] => Array
(
[current-jobs-urgent] => 0
[current-jobs-ready] => 50
[current-jobs-reserved] => 0
[current-jobs-delayed] => 0
[current-jobs-buried] => 0
......結果中顯示處於ready待讀取狀態的job是50個
打開兩個或以上命令行/終端窗口，執行消費者，模擬多消費者競爭
消費者1
PS E:\repository\work\beanstalk> php .\Consumer.php
{"key":"testkey0","value":"testvalue","time":1548039103}
{"key":"testkey1","value":"testvalue","time":1548039103}
{"key":"testkey2","value":"testvalue","time":1548039103}
{"key":"testkey4","value":"testvalue","time":1548039103}
{"key":"testkey6","value":"testvalue","time":1548039103}
{"key":"testkey8","value":"testvalue","time":1548039103}
{"key":"testkey10","value":"testvalue","time":1548039103}
{"key":"testkey12","value":"testvalue","time":1548039103}
{"key":"testkey14","value":"testvalue","time":1548039103}
{"key":"testkey16","value":"testvalue","time":1548039103}
{"key":"testkey18","value":"testvalue","time":1548039103}
{"key":"testkey20","value":"testvalue","time":1548039103}
{"key":"testkey22","value":"testvalue","time":1548039103}
{"key":"testkey24","value":"testvalue","time":1548039103}
{"key":"testkey26","value":"testvalue","time":1548039103}
{"key":"testkey28","value":"testvalue","time":1548039103}
{"key":"testkey30","value":"testvalue","time":1548039103}
{"key":"testkey32","value":"testvalue","time":1548039103}
{"key":"testkey34","value":"testvalue","time":1548039103}
{"key":"testkey36","value":"testvalue","time":1548039103}
{"key":"testkey38","value":"testvalue","time":1548039103}
{"key":"testkey40","value":"testvalue","time":1548039103}
{"key":"testkey42","value":"testvalue","time":1548039103}
{"key":"testkey44","value":"testvalue","time":1548039103}
{"key":"testkey46","value":"testvalue","time":1548039103}
{"key":"testkey48","value":"testvalue","time":1548039103}消費者2
PS E:\repository\work\beanstalk> php .\Consumer.php
{"key":"testkey3","value":"testvalue","time":1548039103}
{"key":"testkey5","value":"testvalue","time":1548039103}
{"key":"testkey7","value":"testvalue","time":1548039103}
{"key":"testkey9","value":"testvalue","time":1548039103}
{"key":"testkey11","value":"testvalue","time":1548039103}
{"key":"testkey13","value":"testvalue","time":1548039103}
{"key":"testkey15","value":"testvalue","time":1548039103}
{"key":"testkey17","value":"testvalue","time":1548039103}
{"key":"testkey19","value":"testvalue","time":1548039103}
{"key":"testkey21","value":"testvalue","time":1548039103}
{"key":"testkey23","value":"testvalue","time":1548039103}
{"key":"testkey25","value":"testvalue","time":1548039103}
{"key":"testkey27","value":"testvalue","time":1548039103}
{"key":"testkey29","value":"testvalue","time":1548039103}
{"key":"testkey31","value":"testvalue","time":1548039103}
{"key":"testkey33","value":"testvalue","time":1548039103}
{"key":"testkey35","value":"testvalue","time":1548039103}
{"key":"testkey37","value":"testvalue","time":1548039103}
{"key":"testkey39","value":"testvalue","time":1548039103}
{"key":"testkey41","value":"testvalue","time":1548039103}
{"key":"testkey43","value":"testvalue","time":1548039103}
{"key":"testkey45","value":"testvalue","time":1548039103}
{"key":"testkey47","value":"testvalue","time":1548039103}
{"key":"testkey49","value":"testvalue","time":1548039103}兩個消費者競爭着完成了全部任務，由於我的beanstalkd啓動時開啓了binlog持久，所以beanstalkd重啓後任務也不會丟失
3.需要注意的事項
1.創建job時，設置的超時時間Pheanstalk::DEFAULT_TTR一定要比消費者處理一個job的時間要長，否則job在超時之後會被tube更改爲ready狀態，被其他消費者獲取，而此時當前消費者還在處理該job，這就出現了一個job被多個消費者重複執行的可怕現象
2.Pheanstalk的維護者發生了變化，在新版的Pheanstalk中是不支持長連接的，當客戶端socket連接服務器時間超過php.ini中設置的default_socket_timeout時，如果未能從服務端tube獲得job，連接將會被斷開，所以消費者進程需要維護，以便在退出後可以重新開啓進程，推薦使用supervisord維護消費者進程。
判斷socket超時的代碼
public function getLine($length = null)
{
$timeout = ini_get('default_socket_timeout');
$timer = microtime(true);
do {
$data = isset($length) ?
$this->_wrapper()->fgets($this->_socket, $length) :
$this->_wrapper()->fgets($this->_socket);
if ($this->_wrapper()->feof($this->_socket)) {
throw new Exception\SocketException('Socket closed by server!');
}
if (($data === false) && microtime(true) - $timer > $timeout) {
$this->disconnect();
throw new Exception\SocketException('Socket timed out!');
}
} while ($data === false);
return rtrim($data);
}