PHP Amazon Ses作为抽象类会产生使用致命错误

Question

I'm using the Amazon Simple Email Service and am trying to implement it as an abstract class so that I can simply use it throughout as needed.

Problem

The problem occurs with the use, I cannot work out how to require the files and classes needed to use Ses as an abstract class without incurring errors.

require 'lib/aws/aws-autoloader.php';

use Aws\Common\Enum\Region;
use Aws\Ses\SesClient;

abstract class simpleemail {

    function sendSesEmail($to, $subject, $body, $bodyHtml){

        try {   
            $client = SesClient::factory(array(
                'key' => "",
                'secret' => "",
                'region' => Region::US_EAST_1
            ));

            $send = $client->sendEmail(array(
                'Source' => 'Name <[e-mail]>',
                'Destination' => array('ToAddresses' => array($to)),
                'Message' => array('Subject' => array('Data' => $subject), 'Body' => array('Html' => array('Data' => $bodyHtml)))));

            return true;
        }
        catch(Exception $e){
            echo $e->getMessage();
            return false;
        }
    }
}

Error Messages

Fatal error: Class 'Aes\Ses\SesClient' not found in ....

I have tried changing the use to require but then get:

require 'lib/aws/Aws/Common/Enum/Region.php';
require 'lib/aws/Aws/Ses/SesClient.php';

Fatal error: 'SesClient' not found in ...

Solution?

How can I use/require the files I need to get this working inside an abstract class?

Answer 1

This doesn't work:

abstract class simpleemail
{
    public function sendSesEmail()
    {
        use Aws\Common\Enum\Region;
        use Aws\Ses\SesClient;
        //...
    }
}

use statements are, basically, imports, that are processed at compile-time, so they can't be scoped. They have to move to the outer scope (outside of the class).
If you want to scope them, you'll have to either, manually require them, or use class_alias.
Check my answer to this question for more details. Even more details can, as ever, be found on php.net

Side-notes:

• Please, follow the coding standards as described by PHP-FIG. They're not official, but Zend, Symfony... all major players, in fact, subscribe to them.
• Please get in the habbit of always specifying the accessmodifiers (public, protected and private)
• When creating instances like you do $client = SesClient::factory, assign them to a property, to only create the instance once. At the moment, each method call creates the same instance over and over again. That's bad
• When using properties: include them in the class definition!
• You're calling sendEmail on an instance, and assign the return value to $send. You don't check the return value, nor do you return it. Either ignore the return value, or return it, so it can be checked!
• Never use require, use require_once if you have to. Using require can cause errors when executing the same block of code twice: redeclaring functions/classes. If time is of the essence, you could opt for require (as require_once causes more overhead), but you have to know what you're doing.
• don't require an autoloader, use spl_autoloader_register
• Remember: Abstract classes can't be instantiated, only their children... children can also override the methods declared in the abstract class. Declare critical methods as final

So, the answer:

use Aws\Common\Enum\Region;
use Aws\Ses\SesClient;
abstract class simpleemail
{
    protected $client = null;
    final public function sendSesEmail()
    {
        $client = $this->getClient();//lazy-loads the client instance
        return $client->sendEmail(/* ... */);//return the result
    }
    //lazy-loader
    protected function getClient()
    {
        if ($this->client === null)
        {
            $this->client = SesClient::factory(array(
                'key' => "",
                'secret' => "",
                'region' => Region::US_EAST_1
            ));
        }
        return $this->client;
    }
}