详解php与ethereum客户端交互

/**

• Debug state
• @var boolean
  */
  private $debug;

/**

• The server URL
• @var string
  */
  private $url;
  /**
• The request id
• @var integer
  */
  private $id;
  /**
• If true,notifications are performed instead of requests
• @var boolean
  */
  private $notification = false;

/**

• Takes the connection parameters
• @param string $url
• @param boolean $debug
  */
  public function __construct($url,$debug = false) {
  // server URL
  $this->url = $url;
  // proxy
  empty($proxy) ? $this->proxy = '' : $this->proxy = $proxy;
  // debug state
  empty($debug) ? $this->debug = false : $this->debug = true;
  // message id
  $this->id = 1;
  }

/**

• Sets the notification state of the object. In this state,notifications are performed,instead of requests.
• @param boolean $notification
  */
  public function setRPCNotification($notification) {
  empty($notification) ?
  $this->notification = false
  :
  $this->notification = true;
  }

/**

• Performs a jsonRCP request and gets the results as an array
• @param string $method
• @param array $params
• @return array
  */
  public function __call($method,$params) {

// check
if (!is_scalar($method)) {
  throw new Exception('Method name has no scalar value');
}

// check
if (is_array($params)) {
  // no keys
  $params = $params[0];
} else {
  throw new Exception('Params must be given as array');
}

// sets notification or request task
if ($this->notification) {
  $currentId = NULL;
} else {
  $currentId = $this->id;
}

// prepares the request
$request = array(
        'method' => $method,'params' => $params,'id' => $currentId
        );
$request = json_encode($request);
$this->debug && $this->debug.='***** Request *****'."\n".$request."\n".'***** End Of request *****'."\n\n";

// performs the HTTP POST
$opts = array ('http' => array (
          'method' => 'POST','header' => 'Content-type: application/json','content' => $request
          ));
$context = stream_context_create($opts);
if ($fp = fopen($this->url,'r',false,$context)) {
  $response = '';
  while($row = fgets($fp)) {
    $response.= trim($row)."\n";
  }
  $this->debug && $this->debug.='***** Server response *****'."\n".$response.'***** End of server response *****'."\n";
  $response = json_decode($response,true);
} else {
  throw new Exception('Unable to connect to '.$this->url);
}

// debug output
if ($this->debug) {
  echo nl2br($debug);
}

// final checks and return
if (!$this->notification) {
  // check
  if ($response['id'] != $currentId) {
    throw new Exception('Incorrect response id (request id: '.$currentId.',response id: '.$response['id'].')');
  }
  if (!is_null($response['error'])) {
    throw new Exception('Request error: '. var_export($response['error'],true));
  }

  return $response['result'];

} else {
  return true;
}

}
}
?>

//PHP自带的dechex无法把大整型转换为十六进制
function bc_dechex($decimal)
{
$result = [];

while ($decimal != 0) {
$mod = $decimal % 16;
$decimal = floor($decimal / 16);
array_push($result,dechex($mod));
}

return join(array_reverse($result));
}

class EthereumRPCClient
{
public static $client = null;

//布署合约的账户地址
const COINBASE = '0x38aabef4cd283ccd5091298dedc88d27c5ec5750';

//合约地址
const CONTRACT = '0xaeab4084194B2a425096fb583Fbcd67385210ac3';

public static function __callStatic($method,$params)
{
$params = count($params) < 1 ? [] : $params[0];

try {
  if (is_null(self::$client)) {
    self::$client = new jsonRPCClient('http://127.0.0.1:8545',true);  
  }
} catch (\Exception $e) {
  echo $e->getMessage();
}

return call_user_func([self::$client,$method],$params);

}

public static function getBalance($address)
{
$method_hash = '0x70a08231';
$method_param1_hex = str_pad(substr($address,2),64,'0',STR_PAD_LEFT);
$data = $method_hash . $method_param1_hex;

$params = ['from' => $address,'to' => self::CONTRACT,'data' => $data];

$total_balance = self::eth_call([$params,"latest"]);

return hexdec($total_balance) / (pow(10,18));

}

public static function transfer($to,$value)
{
self::personal_unlockAccount([self::COINBASE,"123456",3600]);

$value = bcpow(10,18) * $value;

$method_hash = '0xa9059cbb';
$method_param1_hex =str_pad(substr($to,STR_PAD_LEFT);  
$method_param2_hex = str_pad(strval(bc_dechex($value)),STR_PAD_LEFT);

$data = $method_hash . $method_param1_hex . $method_param2_hex;
$params = ['from' => self::COINBASE,'data' => $data];

return self::eth_sendTransaction([$params]);

}

}