Why does PHP tell me this variable isn't defined? - php

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/domain.log");
$array_sp_bots = explode("\n", $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

Answer 2

It is happening because after changing the domain it is not executing inside the loop. Try with -
$all_bots= array(); // Define an empty array
foreach($array_sp_bots as $bots){
if(strpos($bots, "bot")){
$all_bots[] = $bots;
}
}
# count values of strings in array
$bots = array_count_values($all_bots);
If the $array_sp_bots is empty then it would not execute the loop & $all_bots would not be defined. For that case the count would be 0.
Or may might want to add some check for that -
if(empty($all_bots)) {
// Some error message
} else {
# 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);
}