Amazon PHP SDK v1.4.7 set_region bug for EC2: DNS names not properly resolved

Version 1.4.7 of the Amazon PHP SDK added the new Oregon region (along with the United States government private GovCloud region) but introduced a bug rendering the whole library useless as it cannot resolve the correct DNS names.

Prior to v1.4.7, the AmazonEC2 library used these constants (in /usr/share/php/AWSSDKforPHP/services/ec2.class.php):

    /*%******************************************************************************************%*/
    // CLASS CONSTANTS

    /**
     * Specify the default queue URL.
     */
    const DEFAULT_URL = 'ec2.amazonaws.com';

    /**
     * Specify the queue URL for the US-East (Northern Virginia) Region.
     */
    const REGION_US_E1 = 'us-east-1';

    /**
     * Specify the queue URL for the US-West (Northern California) Region.
     */
    const REGION_US_W1 = 'us-west-1';

    /**
     * Specify the queue URL for the EU (Ireland) Region.
     */
    const REGION_EU_W1 = 'eu-west-1';

    /**
     * Specify the queue URL for the Asia Pacific (Singapore) Region.
     */
    const REGION_APAC_SE1 = 'ap-southeast-1';

    /**
     * Specify the queue URL for the Asia Pacific (Japan) Region.
     */
    const REGION_APAC_NE1 = 'ap-northeast-1';

And the code used to reconstruct the DNS entry was

    /**
     * This allows you to explicitly sets the region for the service to use.
     *
     * @param string $region (Required) The region to explicitly set. Available options are <REGION_US_E1>, <REGION_US_W1>, <REGION_EU_W1>, or <REGION_APAC_SE1>.
     * @return $this A reference to the current instance.
     */
    public function set_region($region)
    {
        $this->set_hostname('http://ec2.'. $region .'.amazonaws.com');
        return $this;
    }

With the upgrade to v1.4.7, those constants were changed to a FQDN, while the set_region() function was not changed at all:

    /*%******************************************************************************************%*/
    // CLASS CONSTANTS

    /**
     * Specify the queue URL for the United States East (Northern Virginia) Region.
     */
    const REGION_US_E1 = 'ec2.us-east-1.amazonaws.com';

    /**
     * Specify the queue URL for the United States West (Northern California) Region.
     */
    const REGION_US_W1 = 'ec2.us-west-1.amazonaws.com';

    /**
     * Specify the queue URL for the United States West (Oregon) Region.
     */
    const REGION_US_W2 = 'ec2.us-west-2.amazonaws.com';

    /**
     * Specify the queue URL for the Europe West (Ireland) Region.
     */
    const REGION_EU_W1 = 'ec2.eu-west-1.amazonaws.com';

    /**
     * Specify the queue URL for the Asia Pacific Southeast (Singapore) Region.
     */
    const REGION_APAC_SE1 = 'ec2.ap-southeast-1.amazonaws.com';

    /**
     * Specify the queue URL for the Asia Pacific Northeast (Tokyo) Region.
     */
    const REGION_APAC_NE1 = 'ec2.ap-northeast-1.amazonaws.com';

    /**
     * Specify the queue URL for the United States GovCloud Region.
     */
    const REGION_US_GOV1 = 'ec2.us-gov-west-1.amazonaws.com';

So, for instance, if you were using REGION_US_W1 before,
the old SDK would resolve the url to ‘http://ec2.us-west-1.amazonaws.com’ using set_region()

As of v1.4.7, REGION_US_W1 was changed to
‘ec2.us-west-1.amazonaws.com’
so now set_region() builds the url as the non very pretty
‘http://ec2.ec2.us-west-1.amazonaws.com.amazonaws.com’

and triggers this PHP fatal error

PHP Fatal error:  Uncaught exception 'RequestCore_Exception' with message 'cURL resource: Resource id #62; cURL error: Couldn't resolve host 'ec2.ec2.us-west-1.amazonaws.com.amazonaws.com' (6)' in /usr/share/php/AWSSDKforPHP/lib/requestcore/requestcore.class.php:824
Stack trace:
#0/usr/share/php/AWSSDKforPHP/sdk.class.php(1185): RequestCore->send_request()

To fix the error, modify set_region to:

    public function set_region($region)
    {
        //$this->set_hostname('http://ec2.'. $region .'.amazonaws.com');
        $this->set_hostname('http://'.$region);
        return $this;
    }

——————————————————————
Update 12/07/2011:
Version 1.4.8 of the PHP SDK corrects the bug.

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