Tag Archives: zend framework

JSON and Zend Framework? – Zend_Json

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That’s really a good Zend Framework’s class that help you do the encode/decode job very easily. First of all it escapes everything for you and second it prints a correct/valid code. Note that sometimes if you have a trailing whitespace after the closing PHP tag – ?> that will result in an error.

Here’s some code:

public function jsonAction()
{
	$data = array(3,4,'test', 'my-name' => 3,4);
 
	echo Zend_Json::encode($data);
 
	$this->_helper->viewRenderer->setNoRender(true);
	$this->view->layout()->disableLayout();
}

and the result is:

{"0":3,"1":4,"2":"test","my-name":3,"3":4}

Note that all integers are printed without double quotes – which saves some space!

Download Files with Zend Framework

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Download a File

The title may sound unclear enough, but the task is simple. You’ve to make a file download process within a Zend Framework’s controller. Let’s assume we’ve the DownloadController setup:

<?php
 
class DownloadController extends Zend_Controller_Action
{
	public function indexAction()
	{}	
}

In PHP there are at least three simple lines of code that will do the job of downloading a file.

header('Content-Type: image/jpeg');
header('Content-Disposition: attachment; filename="logo.jpg"');
readfile('images/logo.jpg');

Note that here there is a content-type header, which is important cause the browsers understands what kind of file is supposed to be downloaded. The second line suggests a name of the downloaded file and the third one returns the file to the client.

Download a File … within Zend Framework

Those three lines wont work alone in a ZF application, because there’s no view, but even if you create a .phtml (view) file for this action it won’t work, because the header of the returned file is modified.

The question is how to possibly return the file for download, perhaps write some statistics to the database and if there’s a problem (some permission issues for instance) return a message to the user.

The Basic Solution

The solution is simple. First make it work by disabling the view and possibly the layout for this action:

public function indexAction()
{
	header('Content-Type: image/jpeg');
	header('Content-Disposition: attachment; filename="logo.jpg"');
	readfile('images/logo.jpg');
 
	// disable the view ... and perhaps the layout
	$this->view->layout()->disableLayout();
        $this->_helper->viewRenderer->setNoRender(true);
}

Than add some code where you can check the permissions. Just because there’s no view for this action you can redirect to another – errorAction():

public function indexAction()
{
    if (userHasNoPermissions) {
        $this->view->msg = 'This file cannot be downloaded!';
        $this->_forward('error', 'download');
    }
 
    header('Content-Type: image/jpeg');
    header('Content-Disposition: attachment; filename="logo.jpg"');
    readfile('images/logo.jpg');
 
    // disable layout and view
    $this->view->layout()->disableLayout();
    $this->_helper->viewRenderer->setNoRender(true);
}

But that still will prompt you a file to download, so there should be a return statement that will return false:

public function indexAction()
{
    if (userHasNoPermissions) {
        $this->view->msg = 'This file cannot be downloaded!';
        $this->_forward('error', 'download');
        return FALSE;
    }
 
    header('Content-Type: image/jpeg');
    header('Content-Disposition: attachment; filename="logo.jpg"');
    readfile('images/logo.jpg');
 
    // disable layout and view
    $this->view->layout()->disableLayout();
    $this->_helper->viewRenderer->setNoRender(true);
}

So here’s the complete source of DownloadController.php:

<?php
 
class DownloadController extends Zend_Controller_Action
{
	public function indexAction()
	{
	    if (userHasNoPermissions) {
	        $this->view->msg = 'This file cannot be downloaded!';
	        $this->_forward('error', 'download');
	        return FALSE;
	    }
 
	    header('Content-Type: image/jpeg');
	    header('Content-Disposition: attachment; filename="logo.jpg"');
	    readfile('images/logo.jpg');
 
	    // disable layout and view
	    $this->view->layout()->disableLayout();
	    $this->_helper->viewRenderer->setNoRender(true);
	}	
 
	public function errorAction()
	{}
}

and the error.phtml:

<?php echo $this->msg ?>

Check YouTube Video Existence with Zend_Gdata_YouTube

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The Video Has Been Removed?!

Have you ever seen the famous message on YouTube: “This video has been removed by the user.”, but what if you’re trying to grab that video via the Zend_Gdata_YouTube?

That can happen when you’re reading the feed for a channel or a user’s list of videos. In the feed everything’s OK – once the video is uploaded it appears into the feed. After that the user removes the video and visiting the link from the feed you’ll get the message above.

Actually what happens when you try to read this “video entry” within a Zend Framework’s application. There must be some way to catch this message?

Trying to Catch

The answer is pretty simple! Zend_Gdata_YouTube’s throwing an exception and it can be easily cached. Here’s some source code:

$apiKey = 'your_api_key';
$client = new Zend_Http_Client();
$gdata = new Zend_Gdata_YouTube($client, 'my-app', null, $apiKey);
try {
       $gdata->getVideoEntry($video_id);
} catch(Zend_Gdata_App_Exception $e) {
       echo $e->getMessage();
}

PHP Associative Arrays Coding Style

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No PHP programmer writes code without arrays. Sound strange, but as many programmers there are, as many ways to format the array notation there are.

My advice is to rely on a defined standard. I personally use the Zend Framework’s coding style.

So how to format the code? The first way is on the same line:

$myArray = array('key1' => 'value1',
		 'key2' => 'value2');

And the other, perhaps more clear way is to place the associative pairs on a new line:

$myArray = array(
	'key1' => 'value1',
	'key2' => 'value2',
);

Note that in the second example there’s a comma after the second pair. This is correct PHP syntax and is strongly encouraged!

It’s up to you which way to take. However it mainly depends on the case, but please use standards.