Fatal error: Interface 'Zend\Config\Reader\ReaderInterface' - php

Question

<?php
require_once BLOCKS_ROOT_ENGINE . "Zend/Loader/StandardAutoloader.php";
//require_once BLOCKS_ROOT_ENGINE."library/Zend/Config/Reader/Xml.php";
class Engine {
static public function start() {
$autoLoader = new Zend\Loader\StandardAutoloader(array(
'fallback_autoloader' => true,
));
// register our StandardAutoloader with the SPL autoloader
$autoLoader->register();
$config = new Engine_Zend_Config_Reader_Xml();
//echo $config->config->layout->default->head;
$root = new Core_Root_Blocks_Root();
}
}
The above is located in Engine/Engine.php
The Zend library is located in Engine/Zend/* The autoloader successfully finds the Xml class. But for some strange reason it can not find the interface it implements. what am i doing wrong.
Directory Structure
XML.php
<?php
/**
* Zend Framework (http://framework.zend.com/)
*
* #link http://github.com/zendframework/zf2 for the canonical source repository
* #copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
* #license http://framework.zend.com/license/new-bsd New BSD License
*/
namespace Zend\Config\Reader;
use XMLReader;
use Zend\Config\Exception;
/**
* XML config reader.
*/
class Xml implements ReaderInterface
{
/**
* XML Reader instance.
*
* #var XMLReader
*/
protected $reader;
/**
* Directory of the file to process.
*
* #var string
*/
protected $directory;
/**
* Nodes to handle as plain text.
*
* #var array
*/
protected $textNodes = array(
XMLReader::TEXT,
XMLReader::CDATA,
XMLReader::WHITESPACE,
XMLReader::SIGNIFICANT_WHITESPACE
);
/**
* fromFile(): defined by Reader interface.
*
* #see ReaderInterface::fromFile()
* #param string $filename
* #return array
* #throws Exception\RuntimeException
*/
public function fromFile($filename)
{
if (!is_file($filename) || !is_readable($filename)) {
throw new Exception\RuntimeException(sprintf(
"File '%s' doesn't exist or not readable",
$filename
));
}
$this->reader = new XMLReader();
$this->reader->open($filename, null, LIBXML_XINCLUDE);
$this->directory = dirname($filename);
set_error_handler(
function ($error, $message = '', $file = '', $line = 0) use ($filename) {
throw new Exception\RuntimeException(sprintf(
'Error reading XML file "%s": %s',
$filename, $message
), $error);
}, E_WARNING
);
$return = $this->process();
restore_error_handler();
return $return;
}
/**
* fromString(): defined by Reader interface.
*
* #see ReaderInterface::fromString()
* #param string $string
* #return array|bool
* #throws Exception\RuntimeException
*/
public function fromString($string)
{
if (empty($string)) {
return array();
}
$this->reader = new XMLReader();
$this->reader->xml($string, null, LIBXML_XINCLUDE);
$this->directory = null;
set_error_handler(
function ($error, $message = '', $file = '', $line = 0) {
throw new Exception\RuntimeException(sprintf(
'Error reading XML string: %s',
$message
), $error);
}, E_WARNING
);
$return = $this->process();
restore_error_handler();
return $return;
}
/**
* Process data from the created XMLReader.
*
* #return array
*/
protected function process()
{
return $this->processNextElement();
}
/**
* Process the next inner element.
*
* #return mixed
*/
protected function processNextElement()
{
$children = array();
$text = '';
while ($this->reader->read()) {
if ($this->reader->nodeType === XMLReader::ELEMENT) {
if ($this->reader->depth === 0) {
return $this->processNextElement();
}
$attributes = $this->getAttributes();
$name = $this->reader->name;
if ($this->reader->isEmptyElement) {
$child = array();
} else {
$child = $this->processNextElement();
}
if ($attributes) {
if (!is_array($child)) {
$child = array();
}
$child = array_merge($child, $attributes);
}
if (isset($children[$name])) {
if (!is_array($children[$name]) || !array_key_exists(0, $children[$name])) {
$children[$name] = array($children[$name]);
}
$children[$name][] = $child;
} else {
$children[$name] = $child;
}
} elseif ($this->reader->nodeType === XMLReader::END_ELEMENT) {
break;
} elseif (in_array($this->reader->nodeType, $this->textNodes)) {
$text .= $this->reader->value;
}
}
return $children ?: $text;
}
/**
* Get all attributes on the current node.
*
* #return array
*/
protected function getAttributes()
{
$attributes = array();
if ($this->reader->hasAttributes) {
while ($this->reader->moveToNextAttribute()) {
$attributes[$this->reader->localName] = $this->reader->value;
}
$this->reader->moveToElement();
}
return $attributes;
}
}
ERROR

Answer 1

I think that you missed to set the include paths to Zend Framework library in your index.php file.
The autoloader class loads because you add require_once to the exact file with autoloader class definition. As I understand BLOCKS_ROOT_ENGINE constant is defined in your index.php.
Also I guess that you add somehow /opt/local/apache2/htdocs/blocks path to include paths in index.php - that is because autoloader is able to load Engine_Zend_Config_Reader_Xml class.
It is necessary to add BLOCKS_ROOT_ENGINE in your index.php to include paths list to allow autoloader find Zend\Config\Reader\ReaderInterface.

Answer 2

Not sure if this is your case, but once I ran into strange issues with my students with permission.
One student (with root permission) did something with folder permissions and we were not able to find out what - but files in that folder couldn't be accessible by php any more.
Even file_exists() returned false.
We finnaly resolve issue by copying whole folder, removing original one and renaming copied folder with original name.
Please check if your permissions are ok.

Answer 3

Well the issue had to do with out I set up my autoloader. I downloaded the skeleton ZF2 and found this file that was quite helpful for setting up
<?php
/**
* Zend Framework (http://framework.zend.com/)
*
* #link http://github.com/zendframework/ZendSkeletonApplication for the canonical source repository
* #copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
* #license http://framework.zend.com/license/new-bsd New BSD License
*/
/**
* This autoloading setup is really more complicated than it needs to be for most
* applications. The added complexity is simply to reduce the time it takes for
* new developers to be productive with a fresh skeleton. It allows autoloading
* to be correctly configured, regardless of the installation method and keeps
* the use of composer completely optional. This setup should work fine for
* most users, however, feel free to configure autoloading however you'd like.
*/
// Composer autoloading
if (file_exists('vendor/autoload.php')) {
$loader = include 'vendor/autoload.php';
}
$zf2Path = false;
if (is_dir('vendor/ZF2/library')) {
$zf2Path = 'vendor/ZF2/library';
} elseif (getenv('ZF2_PATH')) { // Support for ZF2_PATH environment variable or git submodule
$zf2Path = getenv('ZF2_PATH');
} elseif (get_cfg_var('zf2_path')) { // Support for zf2_path directive value
$zf2Path = get_cfg_var('zf2_path');
}
if ($zf2Path) {
if (isset($loader)) {
$loader->add('Zend', $zf2Path);
} else {
include $zf2Path . '/Zend/Loader/AutoloaderFactory.php';
Zend\Loader\AutoloaderFactory::factory(array(
'Zend\Loader\StandardAutoloader' => array(
'autoregister_zf' => true
)
));
}
}
if (!class_exists('Zend\Loader\AutoloaderFactory')) {
throw new RuntimeException('Unable to load ZF2. Run `php composer.phar install` or define a ZF2_PATH environment variable.');
}