Zend_Config_Writer
Zend_Config_Writer gives you the ability to write config
files out of Zend_Config objects. It works with an
adapter-less system and thus is very easy to use. By default
Zend_Config_Writer ships with three adapters, which are all
file-based. You instantiate a writer with specific options, which
can be filename and config. Then
you call the write() method of the writer and the config
file is created. You can also give $filename and
$config directly to the write() method.
Currently the following writers are shipped with
Zend_Config_Writer:
Zend_Config_Writer_Array
Zend_Config_Writer_Ini
Zend_Config_Writer_Xml
The INI writer has two modes for rendering with regard to sections.
By default the top-level configuration is always written into section names.
By calling $writer->setRenderWithoutSections(); all options are written
into the global namespace of the INI file and no sections are applied.
As an addition Zend_Config_Writer_Ini has an additional
option parameter nestSeparator, which defines with which
character the single nodes are separated. The default is a single dot,
like it is accepted by Zend_Config_Ini by default.
When modifying or creating a Zend_Config object, there are
some things to know. To create or modify a value, you simply say set
the parameter of the Zend_Config object via the parameter
accessor (->). To create a section in the root or to
create a branch, you just create a new array
("$config->branch = array();"). To define which section
extends another one, you call the setExtend() method
on the root Zend_Config object.
Using Zend_Config_Writer
This example illustrates the basic use of
Zend_Config_Writer_Xml to create a new config file:
production = array();
$config->staging = array();
$config->setExtend('staging', 'production');
$config->production->db = array();
$config->production->db->hostname = 'localhost';
$config->production->db->username = 'production';
$config->staging->db = array();
$config->staging->db->username = 'staging';
// Write the config file in one of the following ways:
// a)
$writer = new Zend_Config_Writer_Xml(array('config' => $config,
'filename' => 'config.xml'));
$writer->write();
// b)
$writer = new Zend_Config_Writer_Xml();
$writer->setConfig($config)
->setFilename('config.xml')
->write();
// c)
$writer = new Zend_Config_Writer_Xml();
$writer->write('config.xml', $config);
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This will create an XML config file with the sections production
and staging, where staging extends production.
Modifying an Existing Config
This example demonstrates how to edit an existing config file.
true,
'allowModifications' => true));
// Modify a value
$config->production->hostname = 'foobar';
// Write the config file
$writer = new Zend_Config_Writer_Ini(array('config' => $config,
'filename' => 'config.ini'));
$writer->write();
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Loading a Config File
When loading an existing config file for modifications it is very
important to load all sections and to skip the extends, so that
no values are merged. This is done by giving the
skipExtends as option to the constructor.
For all the File-Based writers (INI, XML and
PHP Array) internally the render() is used to
build the configuration string. This method can be used from the outside also if you need
to access the string-representation of the configuration data.