<?php
namespace Aws;
use Psr\Http\Message\RequestInterface;
use Aws\Exception\AwsException;
/**
* Represents a history container that is required when using the history
* middleware.
*/
class History implements \Countable, \IteratorAggregate
{
private $maxEntries;
private $entries;
/**
* @param int $maxEntries Maximum number of entries to store.
*/
public function __construct($maxEntries = 10)
{
$this->maxEntries = $maxEntries;
}
public function count()
{
return count($this->entries);
}
public function getIterator()
{
return new \ArrayIterator(array_values($this->entries));
}
/**
* Get the last finished command seen by the history container.
*
* @return CommandInterface
* @throws \LogicException if no commands have been seen.
*/
public function getLastCommand()
{
if (!$this->entries) {
throw new \LogicException('No commands received');
}
return end($this->entries)['command'];
}
/**
* Get the last finished request seen by the history container.
*
* @return RequestInterface
* @throws \LogicException if no requests have been seen.
*/
public function getLastRequest()
{
if (!$this->entries) {
throw new \LogicException('No requests received');
}
return end($this->entries)['request'];
}
/**
* Get the last received result or exception.
*
* @return ResultInterface|AwsException
* @throws \LogicException if no return values have been received.
*/
public function getLastReturn()
{
if (!$this->entries) {
throw new \LogicException('No entries');
}
$last = end($this->entries);
if (isset($last['result'])) {
return $last['result'];
} elseif (isset($last['exception'])) {
return $last['exception'];
} else {
throw new \LogicException('No return value for last entry.');
}
}
/**
* Initiate an entry being added to the history.
*
* @param CommandInterface $cmd Command be executed.
* @param RequestInterface $req Request being sent.
*
* @return string Returns the ticket used to finish the entry.
*/
public function start(CommandInterface $cmd, RequestInterface $req)
{
$ticket = uniqid();
$this->entries[$ticket] = [
'command' => $cmd,
'request' => $req,
'result' => null,
'exception' => null,
];
return $ticket;
}
/**
* Finish adding an entry to the history container.
*
* @param string $ticket Ticket returned from the start call.
* @param mixed $result The result (an exception or AwsResult).
*/
public function finish($ticket, $result)
{
if (!isset($this->entries[$ticket])) {
throw new \InvalidArgumentException('Invalid history ticket');
} elseif (isset($this->entries[$ticket]['result'])
|| isset($this->entries[$ticket]['exception'])
) {
throw new \LogicException('History entry is already finished');
}
if ($result instanceof \Exception) {
$this->entries[$ticket]['exception'] = $result;
} else {
$this->entries[$ticket]['result'] = $result;
}
if (count($this->entries) >= $this->maxEntries) {
$this->entries = array_slice($this->entries, -$this->maxEntries, null, true);
}
}
/**
* Flush the history
*/
public function clear()
{
$this->entries = [];
}
/**
* Converts the history to an array.
*
* @return array
*/
public function toArray()
{
return array_values($this->entries);
}
}
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