/**
     * Test sign request URL
     */
    public function testSignRequestUrl()
    {
        $credentials = new Microsoft_WindowsAzure_Credentials_SharedAccessSignature('myaccount', '', false);
        $queryString = $credentials->createSignedQueryString('pictures/blob.txt', '', 'b', 'r', '2009-02-09', '2009-02-10');
        
        $credentials->setPermissionSet(array(
            'http://blob.core.windows.net/myaccount/pictures/blob.txt?' . $queryString
        ));

        $requestUrl = 'http://blob.core.windows.net/myaccount/pictures/blob.txt?comp=metadata';
        $result = $credentials->signRequestUrl($requestUrl, Microsoft_WindowsAzure_Storage::RESOURCE_BLOB);
        
        $this->assertEquals('http://blob.core.windows.net/myaccount/pictures/blob.txt?comp=metadata&' . $queryString, $result);
    }