$_SERVER Array

Whenever a script is executed, a $_SERVER array is created and passed to the script. This provides information about the context of the script and environment.

The elements of the array are read-only. You can actually modify them from code, but they will not have any effect on the system once the script terminates.

The following table describes the various elements of the array.

Key Description
SCRIPT_NAME Name of the script being executed
SCRIPT_FILENAME Full path and file name of script being executed
SCRIPT_TYPE Can be: http, cron or shell.
http scripts are initiated via a web request.
cron scripts are initiated via the scheduler or exec()
shell scripts are executed via the telnet console.
SCRIPT_FLAGS Only valid for cron scripts. Flags for the script as follows: 
+-------+-------+-------+-------+-------+-------+---------+----------+--------+       
| Bit 8 | Bit 7 | Bit 6 | Bit 5 | Bit 4 | Bit 3 | Bit 2   | Bit 1    | Bit 0  |       
|       |       |       |       | KILL  | SHELL | RUN_NOW | ONE_SHOT | IN_MEM |       
+-------+-------+-------+-------+-------+-------+---------+----------+--------+
IN_MEM - The script is loading in memory and executing or ready to.
ONE_SHOT - This script is not recurring, and has been triggered by a call to exec() or an action, or is the startup script.
RUN_NOW - The script should be run immediately
SHELL - The script is run from the telnet console
KILL - Signals a kill to the script
REMOTE_ADDR Only valid for http scripts. IP address of device initiating request
SERVER_ADDR Only valid for http scripts. IP address of Wattmon device
REQUEST_METHOD Only valid for http scripts. Can be: GET, POST, PUT
HW_PLATFORM Hardware platform currently executing on
0 - WM-60 (the original Wattmon)
1 - WM-PRO WattmonPRO
2 - WM-MINI WattmonMINI
10 - WM-MEGA WattmonMEGA

Examples

Checking the Hardware Platform

<? 
  // check if the device is running on a MINI and issue an alert
  if ($_SERVER['HW_PLATFORM']==2) {
     print("This cannot run on the WM-MINI Device");
  }
?>

Checking the HTTP Method

<? 
  // check that the request method is correct
 
  if ($_SERVER['REQUEST_METHOD']=='POST') {
 
     print("You have sent data via the POST method!");
 
     // at this point the $_POST array will contain variables submitted
     print_r($_POST);
  } else {
     print("You need to submit data to this script via POST.");
     die();
  }
?>

Checking the Script Initiator

<? 
  if ($_SERVER['SCRIPT_TYPE']=='shell') {
     print("This was started through the shell.");
  }
 
  if ($_SERVER['SCRIPT_TYPE']=='http') {
     print("This was started through an http request.");
  }
 
  if ($_SERVER['SCRIPT_TYPE']=='cron') {
     print("This was started through a scheduled task.");
 
     // check the flags to see if it is a one-time call or a recurring execution
     if ($_SERVER['SCRIPT_FLAGS'] & 2 > 0) {
       print("This was started with exec() or via an action, and will only run once.");
     }
  }
?>