5.0-Nano: Portable Cron

5.0-Nano Portable Cron

Uniform Server’s portable Cron has been integrated into 5.0-Nano. It comes complete with two templates one for Drupal and other for Moodle. Well when I say templates they are two lines that require enabling to run the appropriate applications Cron script.

Portable Cron is binary mapped into UniServer’s control space; value assigned is 16 this method makes it easier to integrate with existing control blocks.

Starting Cron a default installation periodically runs scripts that are listed in file run_cron.php, the period being defined by a sleep function. This simple approach is effective however if you wish to add more flexibility this page provides additional information after explaining the basic operation and use.

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Cron

Cron originated from a Unix environment it is a job scheduler allowing scripts to be run automatically at a certain time or date.

Cron (chronograph) has become a more general term referring to a periodic tick.

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Portable Cron

For a permanent installation of UniServer running as a service you can set-up Windows to schedule a task similar to Unix Cron check out How To Schedule Tasks in Windows XP for details?

This is not practical when running UniServer from a USB memory stick. UniServer 5.0-Nano resolves this with a small script scheduler referred to as portable Cron.

It’s fully integrated into UniServers’s control architecture allowing it to be run from either batch files or UniTray.

To run a script or scripts a small amount of configuration is required as explained below.

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Configuration

Each script that requires running is added to the Cron script run_cron.php located in folder UniServer\unicon\main

Edit this file, there are two example lines use these as a template.

Enable a line by removing the two forward slashes. Insert a script’s full url (effectively this is what you would type into a browser to run an applications Cron script).

The two enabled example lines as follows:

 $dummy = file("http://localhost/moodle/admin/cron.php"); // Uncomment to enable 
 $dummy = file("http://localhost/drupal/cron.php");       // Uncomment to enable 

The variable $dummy is just that and is never used.

Note 1: If you have installed the above applications to different folders use the appropriate folder names.

Note 2: If you have moved the servers remember to add a port number to the url.

For example moving the servers once, Apache port becomes 81 and the above two lines need to change as follows:

      
 $dummy = file("http://localhost:81/moodle/admin/cron.php"); // Uncomment to enable 
 $dummy = file("http://localhost:81/drupal/cron.php");       // Uncomment to enable

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Periodic tick

Starting Cron immediately runs all scripts defined in the list. After this, scripts will run periodically defined by variable $cron_time currently set to 15 seconds.

This is a low value suitable only for testing, set a value that is appropriate for the application scripts you are running.

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Running Cron

Start the servers and run cron from either the batch files or UniTray

UniTray

• Start: Left click tray icon > Advanced > click Run Portable Cron
• Stop: Left click tray icon > Advanced > click Stop Portable Cron

Batch files

Navigate to folder UniServer\alternative_control

• Start: Double click Start_Cron.bat
• Stop: Double click Stop_Cron.bat

Note: There can be a delay of up to one second before cron stops.

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General Notes

Binary coded

Control architecture, for independent control Cron has been binary coded with a value of 16.

Example of use

If you wish to start and stop Cron when starting and stopping both servers from UniTray

edit file UniServer\unicon\tray_menu\UniTray1.ini

Change these two lines (Note lines are split so as not to break Wiki formatting):

From:

 Type: item; Caption: "Start UniServer (Apache MySQL)"; Action: shellexecute;
 FileName: "%PHP%\php.exe"; Parameters: " -n %ServerConMain%\start_servers.php 7";
 ShowCmd: hidden; Glyph: 9

 Type: item; Caption: "Stop  UniServer (Apache MySQL)"; Action: shellexecute;
 FileName: "%PHP%\php.exe"; Parameters: " -n %ServerConMain%\stop_servers.php 7";
 ShowCmd: hidden; Glyph: 11

To:

 Type: item; Caption: "Start UniServer (Apache MySQL)"; Action: shellexecute;
 FileName: "%PHP%\php.exe"; Parameters: " -n %ServerConMain%\start_servers.php 23";
 ShowCmd: hidden; Glyph: 9

 Type: item; Caption: "Stop  UniServer (Apache MySQL)"; Action: shellexecute;
 FileName: "%PHP%\php.exe"; Parameters: " -n %ServerConMain%\stop_servers.php 23";
 ShowCmd: hidden; Glyph: 11

Only change required is the parameter value passed to a script. Although I have shown UniTray it also applies to batch files contained in folder UniServer\alternative_control

Note: Binary 1+2+4+16 = 23

1	- Run Apache server
2	- Run MySQL server
4	- Start Index page
16	- Run cron

Portable Cron and Service

Portable Cron may be run when servers are installed as a service.

However will not restart after restarting PC, you need to manually run Portable Cron again.

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Summary

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