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I want to create a config file for my PHP project, but I'm not sure what the best way to do this is.
I have 3 ideas so far.
1-Use Variable
$config['hostname'] = "localhost";
$config['dbuser'] = "dbuser";
$config['dbpassword'] = "dbpassword";
$config['dbname'] = "dbname";
$config['sitetitle'] = "sitetitle";
2-Use Const
define('DB_NAME', 'test');
define('DB_USER', 'root');
define('DB_PASSWORD', '');
define('DB_HOST', 'localhost');
define('TITLE', 'sitetitle');
3-Use Database
I will be using the config in classes so I'm not sure which way would be the best or if there is a better way.
One simple but elegant way is to create a config.php file (or whatever you call it) that just returns an array:
<?php
return array(
'host' => 'localhost',
'username' => 'root',
);
And then:
$configs = include('config.php');
Use an INI file is a flexible and powerful solution! PHP has a native function to handle it properly. For example, it is possible to create an INI file like this:
app.ini
[database]
db_name = mydatabase
db_user = myuser
db_password = mypassword
[application]
app_email = mailer#myapp.com
app_url = myapp.com
So the only thing you need to do is call:
$ini = parse_ini_file('app.ini');
Then you can access the definitions easily using the $ini array.
echo $ini['db_name']; // mydatabase
echo $ini['db_user']; // myuser
echo $ini['db_password']; // mypassword
echo $ini['app_email']; // mailer#myapp.com
IMPORTANT: For security reasons the INI file must be in a non public folder
I use a slight evolution of #hugo_leonardo 's solution:
<?php
return (object) array(
'host' => 'localhost',
'username' => 'root',
'pass' => 'password',
'database' => 'db'
);
?>
This allows you to use the object syntax when you include the php : $configs->host instead of $configs['host'].
Also, if your app has configs you need on the client side (like for an Angular app), you can have this config.php file contain all your configs (centralized in one file instead of one for JavaScript and one for PHP). The trick would then be to have another PHP file that would echo only the client side info (to avoid showing info you don't want to show like database connection string). Call it say get_app_info.php :
<?php
$configs = include('config.php');
echo json_encode($configs->app_info);
?>
The above assuming your config.php contains an app_info parameter:
<?php
return (object) array(
'host' => 'localhost',
'username' => 'root',
'pass' => 'password',
'database' => 'db',
'app_info' => array(
'appName'=>"App Name",
'appURL'=> "http://yourURL/#/"
)
);
?>
So your database's info stays on the server side, but your app info is accessible from your JavaScript, with for example a $http.get('get_app_info.php').then(...); type of call.
The options I see with relative merits / weaknesses are:
File based mechanisms
These require that your code look in specific locations to find the ini file. This is a difficult problem to solve and one which always crops up in large PHP applications. However you will likely need to solve the problem in order to find the PHP code which gets incorporated / re-used at runtime.
Common approaches to this are to always use relative directories, or to search from the current directory upwards to find a file exclusively named in the base directory of the application.
Common file formats used for config files are PHP code, ini formatted files, JSON, XML, YAML and serialized PHP
PHP code
This provides a huge amount of flexibility for representing different data structures, and (assuming it is processed via include or require) the parsed code will be available from the opcode cache - giving a performance benefit.
The include_path provides a means for abstracting the potential locations of the file without relying on additional code.
On the other hand, one of the main reasons for separating configuration from code is to separate responsibilities. It provides a route for injecting additional code into the runtime.
If the configuration is created from a tool, it may be possible to validate the data in the tool, but there is no standard function to escape data for embedding into PHP code as exists for HTML, URLs, MySQL statements, shell commands....
Serialized data
This is relatively efficient for small amounts of configuration (up to around 200 items) and allows for use of any PHP data structure. It requires very little code to create/parse the data file (so you can instead expend your efforts on ensuring that the file is only written with appropriate authorization).
Escaping of content written to the file is handled automatically.
Since you can serialize objects, it does create an opportunity for invoking code simply by reading the configuration file (the __wakeup magic method).
Structured file
Storing it as a INI file as suggested by Marcel or JSON or XML also provides a simple api to map the file into a PHP data structure (and with the exception of XML, to escape the data and create the file) while eliminating the code invocation vulnerability using serialized PHP data.
It will have similar performance characteristics to the serialized data.
Database storage
This is best considered where you have a huge amount of configuration but are selective in what is needed for the current task - I was surprised to find that at around 150 data items, it was quicker to retrieve the data from a local MySQL instance than to unserialize a datafile.
OTOH its not a good place to store the credentials you use to connect to your database!
The execution environment
You can set values in the execution environment PHP is running in.
This removes any requirement for the PHP code to look in a specific place for the config. OTOH it does not scale well to large amounts of data and is difficult to change universally at runtime.
On the client
One place I've not mentioned for storing configuration data is at the client. Again the network overhead means that this does not scale well to large amounts of configuration. And since the end user has control over the data it must be stored in a format where any tampering is detectable (i.e. with a cryptographic signature) and should not contain any information which is compromised by its disclosure (i.e. reversibly encrypted).
Conversely, this has a lot of benefits for storing sensitive information which is owned by the end user - if you are not storing this on the server, it cannot be stolen from there.
Network Directories
Another interesting place to store configuration information is in DNS / LDAP. This will work for a small number of small pieces of information - but you don't need to stick to 1st normal form - consider, for example SPF.
The infrastucture supports caching, replication and distribution. Hence it works well for very large infrastructures.
Version Control systems
Configuration, like code should be managed and version controlled - hence getting the configuration directly from your VC system is a viable solution. But often this comes with a significant performance overhead hence caching may be advisable.
Well - it would be sort of difficult to store your database configuration data in a database - don't ya think?
But really, this is a pretty heavily opinionated question because any style works really and it's all a matter of preference. Personally, I'd go for a configuration variable rather than constants - generally because I don't like things in the global space unless necessary. None of the functions in my codebase should be able to easily access my database password (except my database connection logic) - so I'd use it there and then likely destroy it.
Edit: to answer your comment - none of the parsing mechanisms would be the fastest (ini, json, etc) - but they're also not the parts of your application that you'd really need to focus on optimizing since the speed difference would be negligible on such small files.
You can create a config class witch static properties
class Config
{
static $dbHost = 'localhost';
static $dbUsername = 'user';
static $dbPassword = 'pass';
}
then you can simple use it:
Config::$dbHost
Sometimes in my projects I use a design pattern SINGLETON to access configuration data. It's very comfortable in use.
Why?
For example you have 2 data source in your project. And you can choose witch of them is enabled.
mysql
json
Somewhere in config file you choose:
$dataSource = 'mysql' // or 'json'
When you change source whole app shoud switch to new data source, work fine and dont need change in code.
Example:
Config:
class Config
{
// ....
static $dataSource = 'mysql';
/ .....
}
Singleton class:
class AppConfig
{
private static $instance;
private $dataSource;
private function __construct()
{
$this->init();
}
private function init()
{
switch (Config::$dataSource)
{
case 'mysql':
$this->dataSource = new StorageMysql();
break;
case 'json':
$this->dataSource = new StorageJson();
break;
default:
$this->dataSource = new StorageMysql();
}
}
public static function getInstance()
{
if (empty(self::$instance)) {
self::$instance = new self();
}
return self::$instance;
}
public function getDataSource()
{
return $this->dataSource;
}
}
... and somewhere in your code (eg. in some service class):
$container->getItemsLoader(AppConfig::getInstance()->getDataSource()) // getItemsLoader need Object of specific data source class by dependency injection
We can obtain an AppConfig object from any place in the system and always get the same copy (thanks to static). The init () method of the class is called
In the constructor, which guarantees only one execution. Init() body checks
The value of the config $dataSource, and create new object of specific data source class. Now our script can get object and operate on it, not knowing
even which specific implementation actually exists.
Define will make the constant available everywhere in your class without needing to use global, while the variable requires global in the class, I would use DEFINE. but again, if the db params should change during program execution you might want to stick with variable.
If you think you'll be using more than 1 db for any reason, go with the variable because you'll be able to change one parameter to switch to an entirely different db. I.e. for testing , autobackup, etc.
Here is my way.
<?php
define('DEBUG',0);
define('PRODUCTION',1);
#development_mode : DEBUG / PRODUCTION
$development_mode = PRODUCTION;
#Website root path for links
$app_path = 'http://192.168.0.234/dealer/';
#User interface files path
$ui_path = 'ui/';
#Image gallery path
$gallery_path = 'ui/gallery/';
$mysqlserver = "localhost";
$mysqluser = "root";
$mysqlpass = "";
$mysqldb = "dealer_plus";
?>
Any doubts please comment
One of the simplest form to use config with multiple files is like this:
Files hierarchy:
config
- mail.php
- database.php
mail.php
return [
'smtp_debug' => 0,
];
A helper function:
function config($configFilename, $key)
{
$path = sprintf("config/%s.php", $configFilename);
if (file_exists($path)) {
$config = include sprintf("config/%s.php", $configFilename);
if (isset($config[$key])) {
return $config[$key];
}
}
return '';
}
And you can call it in elegant way:
config('mail','smtp_debug')
I normally end up creating a single conn.php file that has my database connections.
Then i include that file in all files that require database queries.
What about something like this ?
class Configuration
{
private $config;
public function __construct($configIniFilePath)
{
$this->config = parse_ini_file($configIniFilePath, true);
}
/**
* Gets the value for the specified setting name.
*
* #param string $name the setting name
* #param string $section optional, the name of the section containing the
* setting
* #return string|null the value of the setting, or null if it doesn't exist
*/
public function getConfiguration($name, $section = null)
{
$configValue = null;
if ($section === null) {
if (array_key_exists($name, $this->config)) {
$configValue = $this->config[$name];
}
} else {
if (array_key_exists($section, $this->config)) {
$sectionSettings = $this->config[$section];
if (array_key_exists($name, $sectionSettings)) {
$configValue = $sectionSettings[$name];
}
}
}
return $configValue;
}
}
if i have a config file like config.conf (it can be htttp://example.com/config.conf)
user=cacom
version = 2021608
status= true
this is my function:
function readFileConfig($UrlOrFilePath){
$lines = file($UrlOrFilePath);
$config = array();
foreach ($lines as $l) {
preg_match("/^(?P<key>.*)=(\s+)?(?P<value>.*)/", $l, $matches);
if (isset($matches['key'])) {
$config[trim($matches['key'])] = trim($matches['value']);
}
}
return $config;
}
we can use:
$urlRemote = 'http://example.com/default-config.conf';
$localConfigFile = "/home/domain/public_html/config.conf";
$localConfigFile2 = "config.conf";
print_r(readFileConfig($localConfigFile2));
print_r(readFileConfig($localConfigFile));
print_r(readFileConfig($urlRemote));
You can use this simple one:
define('someprop', 0);
and
echo someprop; // output 0
Here it is
<?php
$server = "localhost";
$username = "root";
$password = "";
$db = "your_db_name";
$conn = mysqli_connect($server, $username, $password, $db);
if(!$conn){
die('Error in connecting to server or Database');
}
?>
I am trying to use environment variables that are loaded into my Magento application to override the default database connection credentials.
I've managed to 'almost' get this working using the getenv('MY_CUSTOM_VAR'), however I am trying to use this same method to override the database credentials, so this sensitive data can be stored within the htaccess.
e.g
# .htaccess file
SetEnv DB_USERNAME root
SetEnv DB_PASSWORD password123
SetEnv DB_HOST localhost
My App.php (within app/code/local/Mage/Core/Model/App.php - a copy of the one from the core pool)
// my function that overrides the core one
protected function _initBaseConfig()
{
Varien_Profiler::start('mage::app::init::system_config');
$this->_config->loadBase();
/* Read DB connection config from environment variables */
$connection = $this->_config->getNode('global/resources/default_setup/connection');
$connection->setNode('host', getenv('DB_HOST'));
$connection->setNode('username', getenv('DB_USERNAME'));
$connection->setNode('password', getenv('DB_PASSWORD'));
Varien_Profiler::stop('mage::app::init::system_config');
return $this;
}
I want the $connection just created to be the default global database connection used site-wide, this code should appear to do that but if i enter pure random entries for DB_HOST/DB_PASSWORD etc.. it still connects to the database which suggests that it isn't overriding the default database settings configured with the Magento setup.
Any ideas on how to get this $connection to override and become the 'global' database connection?
P.S Apologies in advance if this question is similar to my previous one, the original question was a bit of a general question whereas this one is much more focused to particular section.
Update...
I have open the local.xml within the app/etc directory and set the 'default setup' database connection to inactive (by changing the active node value to 0) and this as expected returns an error. It would appear the overriding function doesn't seem to like to override the initial db connection.. any ideas guys?
For MySQL db you can do next:
Copy file lib/Zend/Db/Adapter/Mysqli.php to app/code/local/Zend/Db/Adapter/Mysqli.php
Open app/code/local/Zend/Db/Adapter/Mysqli.php and find _connect() function.
In this function near line 317 you'll see:
$_isConnected = #mysqli_real_connect(
$this->_connection,
$this->_config['host'],
$this->_config['username'],
$this->_config['password'],
$this->_config['dbname'],
$port
);
Redefine params:
$this->_config['host'] = getenv('DB_HOST');
$this->_config['username'] = getenv('DB_USERNAME');
$this->_config['password'] = getenv('DB_PASSWORD');
$_isConnected = #mysqli_real_connect(
$this->_connection,
$this->_config['host'],
$this->_config['username'],
$this->_config['password'],
$this->_config['dbname'],
$port
);
Clear cache and restart MySQL. For other databases check files in lib/Zend/Db/Adapter folder (DB2.php, Oracle.php, Sqlsrv.php).
Is it a good practice to initialize an object for an authentication class that does various stuff like register user, login user etc. inside a config file?
The config file mostly does stuff like setting db username, password and site name etc.
Please provide a reason if you don't find this a standard practice. Just to let you know most of the code is procedural except for this particular class.
// MySQL connection settings
$db_host = "localhost";
$db_user = "someuser";
$db_pass = "some pass";
$db_name = "somedb";
// Name of the site
$site_name = "MyDomainName";
$auth = new auth();//initialize Authentication class
$auth->set_auth();//Check if user autorized
In my opinion this is not a good idea. A config file is for configuration, not for execution. I would put this code into a bootstrap.php, so, when you have to edit your code in the future, you know exactly where you can find your configurations and instantiations.
index.php:
include('bootstrap.php');
bootstrap.php:
include('config.php');
$auth = new auth();
$auth->set_auth();
config.php:
$db_host = "localhost";
$db_user = "someuser";
$db_pass = "some pass";
$db_name = "somedb";
The authentication class should be responsible for authenticating, not handling user-specific functions like register/edit/delete. The config object should be available to object needing the configuration data, not the other way around.
The config file should not contain anything other then config data.
I wouldn't do this. "Code" is best kept completely separate from the "configuration files" for a number of reasons. One is that you might have sensitive information in the config files (e.g. passwords) and would want to keep them in a different repository than the code itself. Putting initialisation (which is code) into the Config will mean that it is controlled in two source repositories. Secondly, stuff that "runs" might not be idempotent. The new auth() might set up some state which will make "reloading" the Config a bit of a pain.
It's best you keep a "Config loader" which creates a Config object that contains instantiated classes etc. after reading information from a config file rather than put that init code directly into the file. Also, I wouldn't recommend using executable code as a config file (although this seems to be practice in the PHP world). I would use a format like .ini or yaml and load it up rather than risk evaluating code that's outside my core application.
It is good practice to abstract your code into chunks that have a single purpose, in your case: a config object and a authentication handler. This is related to the KISS Principle, which dictates simplicity by design. In this case: simplicity in code. When you're mixing code, like you're describing, your code gets more complex, because it does more things.
While at first it may not seem complex, this design eventually leads to complex code. For instance: what if another developer joins your team? You'll need to add another config, and conditions to select the right config. This is also the case when working with different environments (development/production).
And what if in some cases you don't want to use the authentication handler? Maybe you're executing an action that doesn't require authentication, or better yet: when authentication is unwanted. More code, more complexity.
By creating chunks of code, whether this is a class, function or an include, you're using loose coupling. This means the chunks don't know about each other, but they can interact. This interaction typically is done by giving the authentication handler a config object that it can use, rather than letting the handler decide what config it uses. This is called dependency injection and is considered a very good way of decoupling your code.
Second, quality code mostly documents itself. Let's say I have to work in your code, I don't know that including a configuration file actually does authentication. I can spend minutes, maybe hours trying to figure out why a session is created when, looking at the code, nothing seems to indicate this.
In your example, I would use something like this:
<?php
include 'config.php'; // contains function that returns config object/array
include 'auth.php'; // contains functions for authentication
// determine environment, based on server variables (ip, script path, etc)
$environment = getEnvironment($_SERVER);
// get config based on environment
$config = getConfig($environment);
// see if authentication is needed
if (needsAuthentication()) {
// perform authentication based on request variables (eg: submitted form fields)
$auth = new auth();
$auth->doAuth($config, $_REQUEST);
}
I am trying to decide on the best way to store my applications configuration settings. There are so many options.
The majority of applications I have seen have used a simple require and a PHP file that contains variables. There seem to be far more advanced techniques out there.
What have you used?
What is most efficient?
What is most secure?
We use a file called Local.php which is excluded from the SCM system. It contains several constants or global variables. For example:
// Local.php
class Setting
{
const URL = 'http://www.foo.com';
const DB_User = 'websmith';
}
And it can be referred to anywhere simply by:
Setting::URL
If you need the settings to be writable at runtime, I suggest you use public static variables instead.
The best thing you can do is the simplest thing that could possibly work (php variables) and wrap it up in a class. That way you can change the implementation later without changing any client code. Create an interface that the configuration class implements and make the client code use the interface methods. If you later decide to store configuration in a database or JSON or whatever, you can simply swap out the existing implementation with a new one. Make sure your configuration class is testable and write unit tests.
Try to use php-arrays config files using technique described here: http://www.dasprids.de/blog/2009/05/08/writing-powerful-and-easy-config-files-with-php-arrays
This method allows you to write app configuration in this way:
app.config.php
<?php
return array(
'appname' => 'My Application Name',
'database' => array(
'type' => 'mysql',
'host' => 'localhost',
'user' => 'root',
'pass' => 'none',
'db' => 'mydb',
),
);
This method is secure, cache-able by opcode cachers (APC, XCACHE).
How about:
; <?php die('Direct access not allowed ;') ?>
; The above is for security, do not remove
[database]
name = testing
host = localhost
user = root
pass =
[soap]
enableCache = 1
cacheTtl = 30
Save as config.php (or something like that, must have php extention), and then just load it with:
parse_ini_file('config.php', true);
And you could use
array_merge_recursive(parse_ini_file('config-default.php', true), parse_ini_file('config.php', true))
to merge a default config file with a more specific config file.
The point here is that you can use the very readable ini format, but still be able to have your config file in a public directory.
When you open the file with your browser, php will parse it first and give you the result, which will just be "; Direct access not allowed ;". When you parse the file directly as an ini file, the php die statement will be commented out according to the ini syntax (;) so it will not have any effect then.
I find Zend_Config to be a good solution. You can load the configuration from a simple array, from an INI style file, or from an XML document. Whichever you choose, the configuration object is the same, so you can switch storage formats freely. Zend_Config objects can also be merged, depending on your application this may be useful (a server config, then a per site/installation config).
As with most (or all) things in the Zend Framework, you can easily use Zend_Config by itself.
Considering efficiency, I'd say the fastest method would be to use an array, since that requires less (in this case no) string parsing. However, a INI/XML format may be easier for some to maintain. Of course some caching would give you the best of both worlds.
Also, using INI files with Zend_Config allow you to define sections of configurations that inherit from each other. The most common use is a 'development' section that inherits from the 'production' section, then redefines the DB/debugging settings.
As for security, keeping the config file out of the web root is the first step. Making it read only and limiting access could make it more secure; however, depending on your hosting/server configuration you may be limited in what can be done there.
Just an example of how to implement a central XML/Xpath configuration.
class Config {
private static $_singleton;
private $xml;
static function getInstance() {
if(is_null (self::$_singleton) ) {
self::$_singleton = new self;
}
return self::$_singleton;
}
function open($xml_file) {
$this->xml = simplexml_load_file($xml_file);
return $this;
}
public function getConfig($path=null) {
if (!is_object($this->xml)) {
return false;
}
if (!$path) {
return $this->xml;
}
$xml = $this->xml->xpath($path);
if (is_array($xml)) {
if (count($xml) == 1) {
return (string)$xml[0];
}
if (count($xml) == 0) {
return false;
}
}
return $xml;
}
}
Example call
Config::getInstance()
->open('settings.xml')
->getConfig('/settings/module/section/item');
In my view good solution would be ini files.
I don't prefer config file using arrays/variables for storing settings; here is why:
What if a user accidently re-named your setting variable?
What if a variable with similar name is defined elsewhere too by the user?
Variables in config file may be overwritten some where deep in the script or even included files.
and possibly more problems....
I like to use ini file for setting of my php apps. Here is why:
It is section based
It is easier
You can set values by friendly names
You don't have to worry about variables being overwritten because there are no ones.
No conflict of variables of course.
It allows more flexibility in specifying the types of values.
Note: You need to use parse_ini_file function to read ini files.
It is best to do any core configuration in PHP itself, but if you are using a database and don't mind the extra overhead - you may find some flexibility in storing some settings in the database with a single extra query (assuming you organize it properly).
Either way, storing this data in JSON, INI, XL, etc is just another unneeded abstraction that is done way too much nowadays on the web. Your best bet is pure PHP, unless you like the flexibility of some settings being in the database.
The only reason I can think of to not use php vars as others are suggesting is if you need to switch between configurations in a controlled manner, so there data/behavior consistency during the switch. For example, if you're switching databases, then the system could write locked until the switch-over occurs (to prevent ghost-writes, but dirty reads are still possible).
If things like this are a concern, then you could write a special admin page in your app(pref local access only for security) that locks the system temporarily, then reads and deploys all your changes before unlocking.
If you're running a high traffic site where consistency matters, this is something you'll want to consider. If you can deploy during off hours when there is little/no traffic, then php vars or other standard text formats will be fine.
I like the idea of having "namespaces" or some kind of tree
so you can have:
db.default.user
or
db.readonly.user
and so on.
now regarding code what I did was an interface for the config readers: so you can have a memory reader, array reader, db reader, etc.
and a config class that uses those readers and allow you have a config from any kind of source
What's the easiest way of storing a single number on a server so that any script can access it, using PHP? Currently, I have a number stored in a file, but this seems somewhat inelegant.
There's no right answer here, but most modern PHP systems for building web applications have some kind of Configuration object. This is often implemented as a singleton
//brain dead config object
class NamespaceConfiguration {
public static function getInstance() {
if (!self::$instance instanceof self) {
self::$instance = new self;
}
return self::$instance;
}
public static function set($key,$value){
//code to set $key/$value paid
}
public static function get($key){
//code to get a $value based on a $key
}
}
$config = NamespaceConfiguration::getInstance();
$config->set('myNumber',42);
....
function somewhereElse(){
$config = NamespaceConfiguration::getInstance();
$myNumber = $config->set('myNumber');
}
This class is loaded on every page requiest. This gives every developer a standard API to call when they want to get or set single configuration values, and allows a single developer to control the where of storage and the how of retrieval (which may be a flat file, XML file, memory cache, MySQL database, XML file stored in a MySQL Database, XML File stored in a MySQL Database that contains a node which points to a file that contains the value, etc.)
The where and how of retrieval is going to depend on your application environment, although by using a configuration object you can create some efficiencies up front (storing already retrieved values in a property cache, pre-fetching certain values on instantiation, etc.)
Since your application probably already have some sort of include-file on the top "header.php" or simular, you could just create a constant/variable in that file, and all the files that include the header will also have access to the constant.
This may help you to define the constant:
http://php.net/constant
That depends on the characteristics of the number. Is it updated/modified often? Is it the only such number? If it isn't changed it's probably better to do as Espo suggests and store it as a php constant that can be included when necessary. If you have other such numbers you can put them all in that file. If they are updated often it's probably better to put it in the database.
But. If it's a single number, that is subject to change, and you don't forsee any need for storing other numbers, why not use a file? Just remember to use flock() when updating it to avoid concurrency issues.
Your best bet would be to put it in a MySQL table for fetching later. That's probably the best way to store information in PHP.
If it is a variable that is more of a environmental nature you could always use set those in Apache
in your httpd.conf file you can set the following:
SetEnv myVar myValue
You can then use $_SERVER to fetch it
$_SERVER['myVar']
I usually set varibles on this if i am to setup same application on a few different virtual hosts but dont want them to have different parameters in the config file.
A config file will also meet your needs.
There is some easy to use classes in Zend framework that can help out
http://framework.zend.com/manual/en/zend.config.html
more specific section 7.3 and 7.4 describes how you can write config parameters in a plain text file or in XML.
if you prefer plain old php you have the function parse_ini_file that lets you read in config parameters from a text file
http://us.php.net/parse_ini_file
You can also use the Alternative PHP Cache or other caching options.
http://www.php.net/manual/en/function.apc-add.php
And you can use this in combination with the other solutions listed above, e.g saving a config to cache.