Ability to disable unixLoadUpperThreshold feature, and warning for Windows users that this feature will not work for them

Author: Jord-JD

README.md

@@ -35,7 +35,7 @@ There are several different configuration variables you can override. The table
 | `cacheDirectory` | The directory in which you wish the cache files to be stored. We recommend you change this to a site-specific directory and ensure it is outside of the web root. You must include a trailing slash. | `/tmp/rwFileCacheStorage/` |
 | `gzipCompression` | Whether or not to compress cache files using gzip. Unless you are storing very small values in your cache files, we recommend you leave this enabled. | `true` |
 | `fileExtension` | The file extension that will be appended to all your cache files. | `cache` |
-| `unixLoadUpperThreshold` | If your server's load is greater than this value, cache files will be returned regardless of whether they have expired. This can be used to prevent cache files being regenerated when server load is high. If you do not wish to use this feature, set this option to an obscenely high value. | `4.00` |
+| `unixLoadUpperThreshold` | If your server's load is greater than this value, cache files will be returned regardless of whether they have expired. This can be used to prevent cache files being regenerated when server load is high. If you do not wish to use this feature, set this option to `-1`. | `4.00` |
 
 ### Setting a cache item
 

src/RWFileCache.php

@@ -2,6 +2,8 @@
 
 namespace rapidweb\RWFileCache;
 
+use Exception;
+
 class RWFileCache
 {
     /**
@@ -112,7 +114,15 @@ public function get($key)
             return false;
         }
 
-        $unixLoad = sys_getloadavg();
+        if (!function_exists('sys_getloadavg')) {
+            throw new Exception('Your PHP installation does not support `sys_getloadavg` (Windows?). Please set `unixLoadUpperThreshold` to `-1` in your RWFileCache config.');
+        }
+
+        if ($this->config['unixLoadUpperThreshold']==-1) {
+            $unixLoad = [0 => PHP_INT_MAX, 1 => PHP_INT_MAX, 2 => PHP_INT_MAX];
+        } else {
+            $unixLoad = sys_getloadavg();
+        }
 
         if ($cacheObj->expiryTimestamp > time() || $unixLoad[0] >= $this->config['unixLoadUpperThreshold']) {
             // Cache item has not yet expired or system load is too high