I'm building my own personal CMS right now with PHP and MySql and I'm not sure of the best way to store site-wide variables such as the site name. What would be the proper way? (If you could provide a brief explanation that would be really nice too. ;)
EDIT: The variables would need to be editable from within the CMS.
In my opinion the best way is to store it in a config file (I use .ini files, but you could easily use a file like below).
I prefer this to storing it in a MySQL database, as it allows you to still get variables (like site name, or admin email address) even if the database is down
<?php
define('SITE_NAME','My CMS');
define('SITE_URL','http://www.example.com');
define('ADMIN_EMAIL','admin@example.com');
?>
EDIT:
Create a table like this
id key value
-------------------
1 name My Cms
2 url http://www.example.com
And access it like this (at the top of every page)
<?php
$config = array();
$query = mysql_query('SELECT * FROM config');
while ($row = mysql_fetch_row($query)) {
$key = $row['key'];
$value = $row['value'];
$config[$key] = $value;
}
echo $config['name'];
?>
There is no "best" sollution for all purposes. Here are some examples how you can do this:
Simple PHP file:
This sollution is very simple but not very flexible: you just 'define' constants:
define('SITE_NAME', 'all about Foo');
define ('ADMIN_NAME', 'The Dude');
define ('ADMIN_MAIL', 'dude@foo.com');
Pro: very very simple.
Cons: changes require that you edit the code. Only flat keys (no tree/registry)
ini File
PHP comes with functions to parse ini files. Here is an example rom the php manual:
; This is a sample configuration file
; Comments start with ';', as in php.ini
[first_section]
one = 1
five = 5
animal = BIRD
[second_section]
path = "/usr/local/bin"
URL = "http://www.example.com/~username"
[third_section]
phpversion[] = "5.0"
phpversion[] = "5.1"
phpversion[] = "5.2"
phpversion[] = "5.3"
you can parse this in a multi dimensional array:
$ini_array = parse_ini_file("sample.ini", true);
print_r($ini_array);
Will output:
Array
(
[first_section] => Array
(
[one] => 1
[five] => 5
[animal] => Dodo bird
)
[second_section] => Array
(
[path] => /usr/local/bin
[URL] => http://www.example.com/~username
)
[third_section] => Array
(
[phpversion] => Array
(
[0] => 5.0
[1] => 5.1
[2] => 5.2
[3] => 5.3
)
)
)
Pros: lexible. A well known standart syntax.
Cons: Hard to edit in backend
See: http://php.net/manual/de/function.parse-ini-file.php
Simple SQL
Another simple aproach, but this uses a database to store the conig keys. The table structure is:
config{config_name UNIQUE KEY VARCHAR[64] ; config_value VARCHAR[128]}
This is only pseudo code and i you need more information about PHP and SQL feel free to google it.
SQL Tree Allows you to create a tree like structure. To archive this you use the same table structure but include '/' in your key names:
admin/name | 'The Dude'
admin/mail | 'dude@foo.com'
Then you load your COMPLETE config in an array and parse it:
function parseRawConfig($rawConfig){
$result = array();
foreach($rawConfig as $key => $value){
$nodeNames = explode('/',$key);
$nodeCount = count($nodes);
$node = $result;
for($i=1;$i<$nodeCount;$i++){
if(!array_key_exists($nodeNames[$i],$node)){
$node[$nodeNames[$i]] = array();
}
}
$node[$nodeNames[$nodeCount-1]] = $value;
}
return $result;
}
Then you can access your keys like this:
echo $config['admin']['mail'];
This makes it easy to generate a nice tree view for your backend, but to save the changes you will have to 'reconstruct' the original path.
Pro: structured hierarchical data.
Con: Complicated, hard to implement, requires db connection
XML Write all your conig settings in a xml file. You can either use a app specific xml or a generic registry like style:
<cmsConf>
<site>all about foo</site>
<admin>
<name>The Dude</name>
<mail>dude@foo.com</mail>
</admin>
</cmsConf>
<reg>
<key name="site">all about foo</key>
<node name="admin">
<key name="name">The Dude</key>
<key name="mail">dude@foo.com</key>
</node>
</reg>
PHP provides plenty of classes and functions for reading/writting xml, and using xml makes it really easy to create interfaces to other applications.
The pros/cons of xml are a huge topic. To huge to sum them up in a few sentences.
IMPORTANT These are just some very simple examples and if you choose one I recommend you dig deeper into the topic!
My fav is XML ;)
I usually create one table with all config variables. Every column will get a clear name of what its setting means. Then I use the following query to store it in a single array for easy use.
<?php
$result = mysql_query("SELECT * FROM configtable WHERE siteID=$siteID LIMIT 1");
$siteConfig = mysql_fetch_assoc($result);
?>
This way it is very easy to add new config parameters, you only need to add a column to the configtable and you can directly use the value in your site. Plus you only have one variable so an accidental reuse of a config variable wont happen.
