hitbtc_example.php

<?php
namespace Hitbtc;

class TradingApi {

	const HITBTC_API_URL = 'http://api.hitbtc.com';
	const HITBTC_TRADING_API_BASE_URI = '/api/1/trading/';

	private $key;
	private $secret;

	public function __construct($key, $secret) {
		$this->key = $key;
		$this->secret = $secret;
	}

	public function getBalance() {
		return $this->request('balance');
	}

	public function getActiveOrders($arguments) {
		return $this->request('orders/active', $arguments);
	}

	public function getRecentOrders($arguments) {
		return $this->request('orders/recent', $arguments);
	}

	public function getTrades($arguments) {
		return $this->request('trades', $arguments);
	}

	public function newOrder($arguments) {
		return $this->request('new_order', $arguments);
	}

	public function cancelOrder($arguments) {
		return $this->request('cancel_order', $arguments);
	}

	protected function request($method, $arguments = array()) {
		$uri = self::HITBTC_TRADING_API_BASE_URI . $method . '?nonce=' . $this->getNonce() . '&apikey=' . $this->key;
		$url = self::HITBTC_API_URL . $uri;
		$postData = $arguments ? http_build_query($arguments, '', '&') : null;
		$signature = $this->getRequestSignature($uri, $postData ? $postData : null);

		$curlOptions = array(
			CURLOPT_CONNECTTIMEOUT => 10,
			CURLOPT_RETURNTRANSFER => true,
			CURLOPT_URL => $url,
			CURLOPT_HTTPHEADER => array('X-Signature: ' . $signature)
		);

		if($postData) {
			$curlOptions[CURLOPT_POST] = true;
			$curlOptions[CURLOPT_POSTFIELDS] = $postData;
		}

		$ch = curl_init();
		curl_setopt_array($ch, $curlOptions);
		$result = curl_exec($ch);
		$code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
		$error = curl_error($ch);
		curl_close($ch);

		if($error || ($code != 200 && $code != 204)) {
			throw new TradingApiRequestFailed("Request to '$url' with POST data $postData failed with code $code and error: " . ($error ? $error : $result), $code);
		}

		if($result && ($resultArray = @json_decode($result, true)) !== false) {
			return $resultArray;
		}
		return $result;
	}

	private function getRequestSignature($uri, $postData = null) {
		return strtolower(hash_hmac('sha512', $uri . $postData, $this->secret));
	}

	private function getNonce() {
		return  round(microtime(true) * 10000);
	}
}

class TradingApiRequestFailed extends \Exception {

}

// Example

$api = new TradingApi('key', 'secret');
var_dump($api->getBalance());