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                <?php  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                namespace Phloppy\Statistic;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use Phloppy\Exception;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use Phloppy\Job;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use Psr\Log\LoggerInterface;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use Psr\Log\NullLogger;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use SebastianBergmann\RecursionContext\InvalidArgumentException;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * Collect Statistics of jobs/sec by node.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                class JobOriginStatistic implements NodeStatistic  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Node Ids  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var \DateTime[]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    private $lastReceived;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * 2-dimensional array storing rates for (queue, nodeId) pairs  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var string[]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    private $stats;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var LoggerInterface  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    private $log;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var float  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    private $alpha;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param float           $alpha Sensitivity factor.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param LoggerInterface $log  | 
            
                            
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                     */  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    function __construct($alpha = 0.9, LoggerInterface $log = null)  | 
            
                            
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                    { | 
            
            
                                                                        
                            
            
                                    
            
            
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                        if (!$log) { | 
            
            
                                                                        
                            
            
                                    
            
            
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                            $log = new NullLogger();  | 
            
            
                                                                        
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                        
                            
            
                                    
            
            
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                        if ((float) $alpha < 0.5 || (float) $alpha > 1.0) { | 
            
            
                                                                        
                            
            
                                    
            
            
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                            throw new InvalidArgumentException('0.5 < $alpha < 1.0'); | 
            
            
                                                                        
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                        
                            
            
                                    
            
            
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                        $this->alpha = (float) $alpha;  | 
            
            
                                                                        
                            
            
                                    
            
            
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                        $this->log = $log;  | 
            
                            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Update jobs by node/sec rt-statistic.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param Job       $job  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param \DateTime $receivedAt  | 
            
                            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return float messages/sec from the given node  | 
            
                            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function update(Job $job, \DateTime $receivedAt = null)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $nodeId = $job->getOriginNode();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $queue = $job->getQueue();  | 
            
                            
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                        if (!$receivedAt) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $receivedAt = new \DateTime('now'); | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        if (!isset($this->lastReceived[$queue][$nodeId])) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $this->lastReceived[$queue][$nodeId] = clone $receivedAt;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        if (!isset($this->stats[$queue])) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $this->stats[$queue] = [];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        if (!isset($this->stats[$queue][$nodeId])) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $this->stats[$queue][$nodeId] = 0.;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $secs = $receivedAt->diff($this->lastReceived[$queue][$nodeId])->s;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        if ($secs < 0) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            $secs = 0;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->lastReceived[$queue][$nodeId] = clone $receivedAt;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        // exp moving average from the last message to now (per sec)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->stats[$queue][$nodeId] =  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            pow($this->alpha, $secs) * $this->stats[$queue][$nodeId] +  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            (1 - $this->alpha);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $this->log->debug('updated value', [ | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            'id' => $nodeId,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            'queue' => $queue,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            'value' => $this->stats[$nodeId],  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            'delta' => $secs  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        ]);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return $this->stats[$nodeId];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Return an ordered list of nodes.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * The list is ordered descending by the frequency of Jobs.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return float[]  | 
            
                            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function nodes($queue)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        assert(arsort($this->stats[$queue]), true);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return $this->stats[$queue];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Return information on a specific (queue, node).  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * If the queue and/or node is not known, no messages have been retrieved from it, so 0. will be returned.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $queue  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param string $nodeId  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                                     | 
                
                 | 
                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    134
                 | 
                                    
                                                     | 
                
                 | 
                     * @return float msg rate (per sec)  | 
            
                            
                    | 
                        
                     | 
                     | 
                     | 
                    
                                                                                                    
                        
                         
                                                                                        
                                                                                     
                     | 
                
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    135
                 | 
                                    
                                                     | 
                
                 | 
                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    136
                 | 
                                    
                                                     | 
                
                 | 
                    public function node($queue, $nodeId)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    137
                 | 
                                    
                                                     | 
                
                 | 
                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    138
                 | 
                                    
                                                     | 
                
                 | 
                        return isset($this->stats[$queue][$nodeId]) ? $this->stats[$queue][$nodeId] : 0.;  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
                | 
                    139
                 | 
                                    
                                                     | 
                
                 | 
                    }  | 
            
            
                                                        
            
                                    
            
            
                | 
                    140
                 | 
                                    
                                                     | 
                
                 | 
                }  | 
            
            
                        
This check looks for
@paramannotations where the type inferred by our type inference engine differs from the declared type.It makes a suggestion as to what type it considers more descriptive.
Most often this is a case of a parameter that can be null in addition to its declared types.