/**
 * Describe Availability Zones Action Sample
 * The DescribeAvailabilityZones operation describes availability zones that are
 * currently available to the account and their states.
 * Availability zones are not the same across accounts. The availability zone
 * us-east-1a for account A is not necessarily the same as us-east-1a for account
 * B. Zone assignments are mapped independently for each account.  
 * @param Amazon_EC2_Interface $service instance of Amazon_EC2_Interface
 * @param mixed $request Amazon_EC2_Model_DescribeAvailabilityZones or array of parameters
 */
function invokeDescribeAvailabilityZones(Amazon_EC2_Interface $service, $request)
{
    try {
        $response = $service->describeAvailabilityZones($request);
        echo "Service Response\n";
        echo "=============================================================================\n";
        echo "        DescribeAvailabilityZonesResponse\n";
        if ($response->isSetResponseMetadata()) {
            echo "            ResponseMetadata\n";
            $responseMetadata = $response->getResponseMetadata();
            if ($responseMetadata->isSetRequestId()) {
                echo "                RequestId\n";
                echo "                    " . $responseMetadata->getRequestId() . "\n";
            }
        }
        if ($response->isSetDescribeAvailabilityZonesResult()) {
            echo "            DescribeAvailabilityZonesResult\n";
            $describeAvailabilityZonesResult = $response->getDescribeAvailabilityZonesResult();
            $availabilityZoneList = $describeAvailabilityZonesResult->getAvailabilityZone();
            foreach ($availabilityZoneList as $availabilityZone) {
                echo "                AvailabilityZone\n";
                if ($availabilityZone->isSetZoneName()) {
                    echo "                    ZoneName\n";
                    echo "                        " . $availabilityZone->getZoneName() . "\n";
                }
                if ($availabilityZone->isSetZoneState()) {
                    echo "                    ZoneState\n";
                    echo "                        " . $availabilityZone->getZoneState() . "\n";
                }
                if ($availabilityZone->isSetRegionName()) {
                    echo "                    RegionName\n";
                    echo "                        " . $availabilityZone->getRegionName() . "\n";
                }
                $messageList = $availabilityZone->getMessage();
                foreach ($messageList as $message) {
                    echo "                    Message\n";
                    echo "                        " . $message;
                }
            }
        }
    } catch (Amazon_EC2_Exception $ex) {
        echo "Caught Exception: " . $ex->getMessage() . "\n";
        echo "Response Status Code: " . $ex->getStatusCode() . "\n";
        echo "Error Code: " . $ex->getErrorCode() . "\n";
        echo "Error Type: " . $ex->getErrorType() . "\n";
        echo "Request ID: " . $ex->getRequestId() . "\n";
        echo "XML: " . $ex->getXML() . "\n";
    }
}