The System tab (see Figure 10-19) is used for various configurations, including setting the path of the log folder; specifying the location of the help server; and enabling, disabling, or setting the time for caching and sessions.
1. System Settings (System Tab)
In the Path to Log Folder field, you specify the location in which the logs will be stored. This path is automatically filled in by the Joomla installer. You can use the log files to see information about the latest visitors to your web site, the bandwidth used by the site, any errors, and so on. You don’t have to open the logs with a text editor; the Control Panels of most hosting companies provide a GUI (something like Figure 10-20) that reads the information from the log files and presents it in an easily understandable format.
Some web hosting companies provide icons, as shown in Figure 10-21, to extract information from the log files and present a report in the desired format.
Back to System Settings; the Help Server field is used to display help screens when the user clicks the Help icon. By default, the server that’s specified in the Help Server drop-down list is a remote server, help.joomla.org, but you can also set up your own local help sever.
2. Debug Settings (System Tab)
With the debug settings, you can decide whether to apply the debug system on your Joomla web site and whether to display debug indicators in case of bugs.
The Debug System option is used to detect any bugs that may occur during an operation performed on the front-or back end of your Joomla web site. If you set this option to Yes, it will activate Joomla’s debug
system, and you will start getting diagnostic information, language translations, and SQL errors. That is, you will start getting debugging information at the end of each page of your web site that includes the following:
- Profile information (the amount of time it takes to execute code up to various points in the code)
- Memory usage (the amount of RAM used)
- SQL queries executed for building the page
- Language files loaded (all the language files loaded for building the page, along with their full path and the number of times the file was referenced)
- Untranslated string diagnostics (list of all the untranslated strings found)
- Untranslated string designer (list of all the untranslated strings found in a key = value format).
After you set the Debug System option to Yes, the debug information may look something like that shown in Figure 10-22.
You get more detailed information after clicking the links provided in the debug console. For example, you get the profile information shown in Figure 10-23 when you click the Profile Information link.
Back to Debug Settings; the Debug Language option is used for switching on the debugging indicators for the Joomla language files. That is, all translatable text is enclosed in special characters that reflect their status. Any text enclosed in bullets indicates that a match has been found in the language definition file, and the text has been translated. Any text enclosed in pairs of asterisks (**) indicates that the string is translatable, but no match was found in the language definition file. Text with no surrounding characters indicates that the string is not translatable. You can use language debugging without enabling the Debug System option, but if you do, you won’t get additional detailed information about the bugs to help you correct them.
An example of the use of the Debug Language option on the front end of a Joomla web site (displaying text enclosed in asterisks) is shown in Figure 10-24.
3. Cache Settings (System Tab)
The cache is a small, temporary storage area on the hard drive in which browsers keep web site contents that have been repeatedly viewed by visitors. In this way, caching is a technique to improve the speed of displaying web site contents. Recall that because the web site is a CMS, whatever contents you see on it are accessed from the MySQL database. Using caching, Joomla creates a local copy of the contents being viewed (a cache) on the server’s hard disk, so the next time the contents are requested by the visitor, Joomla can access them from there.
The options in the Cache Settings section of Global Configuration are as follows:
- Cache: You can set the value of this option to any of the following values, depending on your requirement:
- ON — Conservative caching: Enables basic caching of your web pages and content
- ON — Progressive caching: Enables caching for the site that either does not change often or is a bulky site
- OFF – Caching disabled: Disables caching on your site
- Cache Handler: Displays how the caching is There are two caching mechanisms:
- File: In file-based caching, reading and writing operations are performed using the file That is, the read operations read from an area in system memory known as the system file cache instead of the physical disk. Similarly, for write operations, the data is written to the system file cache rather than to the disk.
- Cache_Lite: A faster caching system that focuses on enhancing PHP
- Cache Time: The amount of time to keep the local copy of the contents before refreshing When the time specified in this field expires, Joomla updates the local copy maintained in the cache with that of the MySQL database contents (to display the latest updated information). The default value is 15 minutes (after every 15 minutes, the contents of the cache will be refreshed automatically).
4. Session Settings (System Tab)
Sessions allow your system to recognize that requests are being generated by the same client (visitor). This not only helps to remember the options selected by a particular visitor on your web site (such as products selected in a shopping cart) but also prevents visitors from having to perform repetitive tasks (e.g., a visitor who has logged in once should not be asked to log in again when accessing another page of your web site).
The options in the Session Settings section of Global Configuration are as follows:
- Session Lifetime: This field determines how long a session should last and how long a user can remain signed in after being inactive. The default value is 15 minutes, which means that a visitor who logs into your web site and doesn’t perform any action for more than 15 minutes will be prompted to log in again.
- Session Handler: This drop-down list determines how the session should be handled after a user connects and logs into the site. The default setting is Database, which means that all the actions taken by the visitor on the webpage are temporarily stored in a database until the visitor either logs out or closes the browser window. If you set the value of this option to None, your Joomla web site won’t be able to maintain the session (i.e., it won’t be able to recognize whether the requests have been made by the same user).
Source: Harwani B M (2015), Foundations of Joomla!, Apress; 2nd ed edition