fix: ping fails on servers that don't set PATH in cron (#7603)

* fix: ping fails on servers that don't set PATH in cron
Find the full path to fping and persist it in the database.
Adds the ability to persist settings with Config::set()

* Add ability to set webui settings.
No display of for paths, because it would be inconsistent.

LibreNMS/Config.php

@@ -157,10 +157,31 @@ class Config
      *
      * @param mixed $key period separated config variable name
      * @param mixed $value
+     * @param bool $persist set the setting in the database so it persists across runs
+     * @param string $default default (only set when initially created)
+     * @param string $descr webui description (only set when initially created)
+     * @param string $group webui group (only set when initially created)
+     * @param string $sub_group webui subgroup (only set when initially created)
      */
-    public static function set($key, $value)
+    public static function set($key, $value, $persist = false, $default ='', $descr='', $group='', $sub_group='')
     {
         global $config;
+
+        if ($persist) {
+            $res = dbUpdate(array('config_value' => $value), 'config', '`config_name`=?', array($key));
+            if (!$res && !dbFetchCell('SELECT 1 FROM `config` WHERE `config_name`=?', array($key))) {
+                $insert = array(
+                    'config_name' => $key,
+                    'config_value' => $value,
+                    'config_default' => $default,
+                    'config_descr' => $descr,
+                    'config_group' => $group,
+                    'config_sub_group' => $sub_group,
+                );
+                dbInsert($insert, 'config');
+            }
+        }
+
         $keys = explode('.', $key);
 
         $curr = &$config;

includes/defaults.inc.php

@@ -42,8 +42,8 @@ $config['db_socket']             = null;
 $config['own_hostname'] = 'localhost';
 
 // Location of executables
-$config['fping']                    = 'fping';
-$config['fping6']                   = 'fping6';
+//$config['fping']                    = '/usr/sbin/fping';
+//$config['fping6']                   = '/usr/sbin/fping6';
 $config['fping_options']['retries'] = 3;
 $config['fping_options']['timeout'] = 500;
 $config['fping_options']['count']   = 3;

includes/functions.php

@@ -2318,3 +2318,23 @@ function return_num($entry)
         return $num_response[0];
     }
 }
+
+/**
+ * Locate the actual path of a binary
+ *
+ * @param $binary
+ * @return mixed
+ */
+function locate_binary($binary)
+{
+    if (!str_contains($binary, '/')) {
+        $output = `whereis -b $binary`;
+        $target = trim(substr($output, strpos($output, ':') + 1));
+
+        if (file_exists($target)) {
+            return $target;
+        }
+    }
+
+    return $binary;
+}

includes/process_config.inc.php

@@ -23,6 +23,8 @@
  * @author     Neil Lathwood <neil@lathwood.co.uk>
  */
 
+use LibreNMS\Config;
+
 if (empty($config['email_from'])) {
     $config['email_from'] = '"' . $config['project_name'] . '" <' . $config['email_user'] . '@' . php_uname('n') . '>';
 }
@@ -42,3 +44,10 @@ if ($config['secure_cookies']) {
 if ($config['rrdgraph_real_95th']) {
     $config['rrdgraph_real_percentile'] = $config['rrdgraph_real_95th'];
 }
+
+// make sure we have full path to binaries in case PATH isn't set
+foreach (array('fping', 'fping6') as $bin) {
+    if (!is_executable(Config::get($bin))) {
+        Config::set($bin, locate_binary($bin), true, $bin, "Path to $bin", 'external', 'paths');
+    }
+}

tests/ConfigTest.php

@@ -119,6 +119,29 @@ class ConfigTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals("I'll be there", $config['you']['and']['me']);
     }
 
+    public function testSetPersist()
+    {
+        if (getenv('DBTEST')) {
+            dbConnect();
+            dbBeginTransaction();
+        } else {
+            $this->markTestSkipped('Database tests not enabled.  Set DBTEST=1 to enable.');
+        }
+
+        $key = 'testing.persist';
+
+        dbDelete('config', '`config_name`=?', array($key)); // FIXME dbInsert breaks transactions
+        $this->assertNull(dbFetchCell('SELECT `config_value` FROM `config` WHERE `config_name`=?', array($key)), "$key should not be set, clean database");
+        Config::set($key, 'one', true);
+        $this->assertEquals('one', dbFetchCell('SELECT `config_value` FROM `config` WHERE `config_name`=?', array($key)));
+        Config::set($key, 'two', true);
+        $this->assertEquals('two', dbFetchCell('SELECT `config_value` FROM `config` WHERE `config_name`=?', array($key)));
+
+        if (getenv('DBTEST')) {
+            dbRollbackTransaction();
+        }
+    }
+
     public function testHas()
     {
         Config::set('long.key.setting', 'no one cares');