Zend - Infrastructure

• Zend_Config
• Use/Purpose
  
  

  designed to simplify access to, and use of , configuration data within applications.

• Multiple Environs
  
  
  • PHP Array
    <?php

//Given an array of configuration data
$configArray = array(
'webhost' => 'ww.example.com',
'database' => array(...
)
);

//Create the object-oriendted wrapper upon the configuration dataconsumption
require_once 'Zend/Config.php';
$config = new Zend_Config(configArray );
//Print a configuration datum (results in 'ww.example.com')

echo $config->webhost;

  • PHP Configuration File
    <?php
//config.php
return array(
'webhost' => 'ww.example.com',
'database' => array(...

<?php
//Configuration consumption
require_once 'Zend/Config.php';
$config = new Zend_Config(require 'config.php');

//Print a configuration datum (results in 'ww.example.com')
echo $config->webhost;
    Zend_Config實作了Countable及Iterator interfaces，因此可用count()及foreach
    Two Zend_Config objects can be merged into a single object using the merge() function
    
• .ini Files
  
  
  • .ini可宣告[production],[testing],[development]等，配合環境變數讀取不同的config
    
    

    $config = new Zend_Config_Ini('/path/to/config.ini'),'staging');
    echo $config->database->params->hosts;

    [staging:production] //staging繼承production的變數
    

    不要把變數內容值用單引號包起來，會把單引號當成值

  • Zend_Config_Xml
    
    

    $config = new Zend_Config_Xml('/path/to/config.xml'),'staging');
    echo $config->database->params->hosts;

    
    
• Bootstrap File
• Config Objects
• Zend_Exception
  Purpose: recover from the failure
  <?php
try{
Zend_Loader::loadClass('nonexistantclass');
}catch (Zend_Exception $e){
echo "Caught exception: " . get_class($e) . "\n";
echo "Message: " . $e->getMessage() . "\n";
//other code to recover from the failure;
}
  
• Zend_Registry
  Purpose: a container for storing objects and values in the application space.
  Constructing a Registry
  <?php
$registry = new Zend_Registry(array('index' => $value));
  
  Initializing the Static Registry
  <?php
Zend_Registry::setInstance(array('index' => $value));
  
  The setInstance() method throws Zend_Exception if the static registry has already been initialized
  
• Zend_Version
  <?php
//return -1(older), 0(the same) or 1(newer)
$cmp = Zend_Version::compareVBersion('1.0.0');
• Zend_Loader
  Purpose: includes methods to help you load files dynamically
  Zend_Loader::loadFile($filename,$path,$once) is a wrapper for the PHP function include() and throws Zend_Exception on failure.
  limit: $filename argument can only contain alphanumeric characters, hyphens("-"), or periods("."), and must not contain any path information.
  $once is boolean, if TRUE, equals include_once(), otherwise include() is used.
  
  Loading Classes
  limit:同loadFile,多了underscores("_")
  Zend_Loader::loadClass($class, $dirs)
  $class = "Container_Tree"; //equals Container/Tree.php
  <?php
Zend_Loader::loadClass('Container_Tree',
 array(
  '/home/productioin/mylib',
  '/home/productioin/myapp'
 )
);
  會在給予的路徑參數中找claess,如果找不到就丟了Zend_Exception
  Plugin Loader
  <?php
$loader = new Zend_Loader_PluginLoader();
$loader->addPrefixPath('Zend_View_Helper', 'Zend/View/elper/')
    ->addPrefixPath('Foo_View_Helper','application/modules/foo/views/helpers');

• Zend_Session
  Purpose: helps manage and preserve session data, a logical complement of cookie data, across multiple page requests by the same client.
  

  Zend_Session_Namespace

  就是PHP中的$_SESSION
  $sess = new Zend_Session_Namespace();
$sees->tree = $tree;
  

  Operation

  當第一個session被requested時，Zend_Session就自動啟動PHP session,不必等到Zend_Session::start().
  The PHP session will use defaults from Zend_Session, unless modified by Zend_Session::setOptions().