为什么PHP告诉我这个变量没有定义？

Question

I'm trying to filter some logs like I need them and tried to it dynamic. I have some domains and I'm trying to filter some things from it, and it all works like I want it - but now I changed the domain name and now my code doesn't work anymore. It says one variable isn't defined.

      $sp_bots = shell_exec("grep bot | awk '{print $12}' /var/www/laravel/logs/vhosts/zahnmedizinisches-fachzentrum-berlin.de.log");
    $array_sp_bots = explode("
", $sp_bots);
    $all_bots = array();
    foreach($array_sp_bots as $bots){
        if(strpos($bots, "bot")){
            $all_bots[] = $bots;
        }
    }
    # count values of strings in array
    if (!empty( $all_bots )) {
        $bots = array_count_values($all_bots);
        arsort($bots);
        $mostOccuring = max(array_count_values($all_bots));
        $bot_keys = array_keys($bots);
        #number of total bots
        $count_bots = count($all_bots);
    }

and in my returns:

return view('/domains/data', [

       'count_bots' => $count_bots,
        'bot_keys' => $bot_keys,
        'mostOccuring' => $mostOccuring,
    ]);

but all three variables in my return are undefined.. anybody knows why?

Answer 1

You have to initialize the array as an empty array before the loop:

$all_bots = array();          //init the empty array

foreach($array_sp_bots as $bots)
{
    if(strpos($bots, "bot"))
    {
        $all_bots[] = $bots;  //here you can add elements to the array
    }
}

in your case, if the loop does not execute at least one time, the variable $all_bots will be undefined

EDIT

After the loop, to handle the case when the array is empty do somthing like this:

//if there is some element in all_bots...
if ( ! empty( $all_bots ) )
{
    # count values of strings in array
    $bots = array_count_values($all_bots);
    arsort($bots);
    $mostOccuring = max(array_count_values($all_bots));
    $bot_keys = array_keys($bots);
    #number of total bots
    $count_bots = count($all_bots);
}
//handle the case the variable all_bots is empty
else
{
    $bots = 0;
    $count_bots = 0;
    $bot_keys = 0;
    $mostOccuring = 0;
}

EDIT2

You have the variables undefined in your return because when all $all_bots is empty they are not set. Check my edit above, i have added them to the if statement. But you have to handle this case in your application according to your needs, think this way: What these variables should contain when $all_bots is empty? Then assign the values to the variables in the if statement