Zend\Config\Reader

Zend\Config\Reader gives you the ability to read a config file. It works with concrete implementations for different file format. The Zend\Config\Reader is only an interface, that define the two methods fromFile() and fromString(). The concrete implementations of this interface are:

• Zend\Config\Reader\Ini
• Zend\Config\Reader\Xml
• Zend\Config\Reader\Json
• Zend\Config\Reader\Yaml

The fromFile() and fromString() return a PHP array contains the data of the configuration file.

Note

Differences from ZF1

The Zend\Config\Reader component no longer supports the following features:

• Inheritance of sections.
• Reading of specific sections.

Zend\Config\Reader\Ini

Zend\Config\Reader\Ini enables developers to store configuration data in a familiar INI format and read them in the application by using an array syntax.

Zend\Config\Reader\Ini utilizes the parse_ini_file() PHP function. Please review this documentation to be aware of its specific behaviors, which propagate to Zend\Config\Reader\Ini, such as how the special values of “TRUE”, “FALSE”, “yes”, “no”, and “NULL” are handled.

Note

Key Separator

By default, the key separator character is the period character (“.”). This can be changed, however, using the setNestSeparator() method. For example:

$reader = new Zend\Config\Reader\Ini();
$reader->setNestSeparator('-');

The following example illustrates a basic use of Zend\Config\Reader\Ini for loading configuration data from an INI file. In this example there are configuration data for both a production system and for a staging system. Suppose we have the following INI configuration file:

webhost                  = 'www.example.com'
database.adapter         = 'pdo_mysql'
database.params.host     = 'db.example.com'
database.params.username = 'dbuser'
database.params.password = 'secret'
database.params.dbname   = 'dbproduction'

We can use the Zend\Config\Reader\Ini to read this INI file:

$reader = new Zend\Config\Reader\Ini();
$data   = $reader->fromFile('/path/to/config.ini');

echo $data['webhost']  // prints "www.example.com"
echo $data['database']['params']['dbname'];  // prints "dbproduction"

The Zend\Config\Reader\Ini supports a feature to include the content of a INI file in a specific section of another INI file. For instance, suppose we have an INI file with the database configuration:

database.adapter         = 'pdo_mysql'
database.params.host     = 'db.example.com'
database.params.username = 'dbuser'
database.params.password = 'secret'
database.params.dbname   = 'dbproduction'

We can include this configuration in another INI file, for instance:

webhost  = 'www.example.com'
@include = 'database.ini'

If we read this file using the component Zend\Config\Reader\Ini we will obtain the same configuration data structure of the previous example.

The @include = 'file-to-include.ini' can be used also in a subelement of a value. For instance we can have an INI file like that:

adapter         = 'pdo_mysql'
params.host     = 'db.example.com'
params.username = 'dbuser'
params.password = 'secret'
params.dbname   = 'dbproduction'

And assign the @include as subelement of the database value:

webhost           = 'www.example.com'
database.@include = 'database.ini'

Zend\Config\Reader\Xml

Zend\Config\Reader\Xml enables developers to read configuration data in a familiar XML format and read them in the application by using an array syntax. The root element of the XML file or string is irrelevant and may be named arbitrarily.

The following example illustrates a basic use of Zend\Config\Reader\Xml for loading configuration data from an XML file. Suppose we have the following XML configuration file:

<?xml version="1.0" encoding="utf-8"?>?>
<config>
    <webhost>www.example.com</webhost>
    <database>
        <adapter value="pdo_mysql"/>
        <params>
            <host value="db.example.com"/>
            <username value="dbuser"/>
            <password value="secret"/>
            <dbname value="dbproduction"/>
        </params>
    </database>
</config>

We can use the Zend\Config\Reader\Xml to read this XML file:

$reader = new Zend\Config\Reader\Xml();
$data   = $reader->fromFile('/path/to/config.xml');

echo $data['webhost']  // prints "www.example.com"
echo $data['database']['params']['dbname'];  // prints "dbproduction"

Zend\Config\Reader\Xml utilizes the XMLReader PHP class. Please review this documentation to be aware of its specific behaviors, which propagate to Zend\Config\Reader\Xml.

Using Zend\Config\Reader\Xml we can include the content of XML files in a specific XML element. This is provided using the standard function XInclude of XML. To use this function you have to add the namespace xmlns:xi="http://www.w3.org/2001/XInclude" to the XML file. Suppose we have an XML files that contains only the database configuration:

<?xml version="1.0" encoding="utf-8"?>
<config>
    <database>
        <adapter>pdo_mysql</adapter>
        <params>
            <host>db.example.com</host>
            <username>dbuser</username>
            <password>secret</password>
            <dbname>dbproduction</dbname>
        </params>
    </database>
</config>

We can include this configuration in another XML file, for instance:

<?xml version="1.0" encoding="utf-8"?>
<config xmlns:xi="http://www.w3.org/2001/XInclude">
    <webhost>www.example.com</webhost>
    <xi:include href="database.xml"/>
</config>

The syntax to include an XML file in a specific element is <xi:include href="file-to-include.xml"/>

Zend\Config\Reader\Json

Zend\Config\Reader\Json enables developers to read configuration data in a JSON format and read them in the application by using an array syntax.

The following example illustrates a basic use of Zend\Config\Reader\Json for loading configuration data from a JSON file. Suppose we have the following JSON configuration file:

{
  "webhost"  : "www.example.com",
  "database" : {
    "adapter" : "pdo_mysql",
    "params"  : {
      "host"     : "db.example.com",
      "username" : "dbuser",
      "password" : "secret",
      "dbname"   : "dbproduction"
    }
  }
}

We can use the Zend\Config\Reader\Json to read this JSON file:

$reader = new Zend\Config\Reader\Json();
$data   = $reader->fromFile('/path/to/config.json');

echo $data['webhost']  // prints "www.example.com"
echo $data['database']['params']['dbname'];  // prints "dbproduction"

Zend\Config\Reader\Json utilizes the Zend\Json\Json class.

Using Zend\Config\Reader\Json we can include the content of a JSON file in a specific JSON section or element. This is provided using the special syntax @include. Suppose we have a JSON file that contains only the database configuration:

{
  "database" : {
    "adapter" : "pdo_mysql",
    "params"  : {
      "host"     : "db.example.com",
      "username" : "dbuser",
      "password" : "secret",
      "dbname"   : "dbproduction"
    }
  }
}

We can include this configuration in another JSON file, for instance:

{
    "webhost"  : "www.example.com",
    "@include" : "database.json"
}

Zend\Config\Reader\Yaml

Zend\Config\Reader\Yaml enables developers to read configuration data in a YAML format and read them in the application by using an array syntax. In order to use the YAML reader we need to pass a callback to an external PHP library or use the Yaml PECL extension.

The following example illustrates a basic use of Zend\Config\Reader\Yaml that use the Yaml PECL extension. Suppose we have the following YAML configuration file:

webhost: www.example.com
database:
    adapter: pdo_mysql
    params:
      host:     db.example.com
      username: dbuser
      password: secret
      dbname:   dbproduction

We can use the Zend\Config\Reader\Yaml to read this YAML file:

$reader = new Zend\Config\Reader\Yaml();
$data   = $reader->fromFile('/path/to/config.yaml');

echo $data['webhost']  // prints "www.example.com"
echo $data['database']['params']['dbname'];  // prints "dbproduction"

If you want to use an external YAML reader you have to pass the callback function in the constructor of the class. For instance, if you want to use the Spyc library:

// include the Spyc library
require_once ('path/to/spyc.php');

$reader = new Zend\Config\Reader\Yaml(array('Spyc','YAMLLoadString'));
$data   = $reader->fromFile('/path/to/config.yaml');

echo $data['webhost']  // prints "www.example.com"
echo $data['database']['params']['dbname'];  // prints "dbproduction"

You can also instantiate the Zend\Config\Reader\Yaml without any parameter and specify the YAML reader in a second moment using the setYamlDecoder() method.

Using Zend\Config\ReaderYaml we can include the content of a YAML file in a specific YAML section or element. This is provided using the special syntax @include. Suppose we have a YAML file that contains only the database configuration:

database:
    adapter: pdo_mysql
    params:
      host:     db.example.com
      username: dbuser
      password: secret
      dbname:   dbproduction

We can include this configuration in another YAML file, for instance:

webhost:  www.example.com
@include: database.yaml