What is the proper way to find an 'internal server error 500' in php?

Question

I am continuously having this internal server error to a very simple php code working with JSON. The values I am logging from the code is absolutely correct, yet when in action I am getting an internal server error 500 from this particular code. I had a similar code working previously. What am I doing wrong? or how should I proceed with debugging the error?

<?php

$var2 = $_POST['phn'];
$phone_received = json_decode($var2);

$adb = PearDatabase::getInstance();

$query1 = "SELECT addressid FROM address WHERE mobile = ?"; 
$leadID = $adb->pquery($query1, array($phone_received));

$row= $adb->num_rows($leadID);

if ($row != 0) {      
    $result = 'This number has already been used in the system.';
    echo json_encode($result); 
}else{
    $result = 'Good to go!';
    echo json_encode($result); 
}    

?>

[How do I get PHP errors to display?](https://stackoverflow.com/questions/1053424/how-do-i-get-php-errors-to-display) — FirstOne, Nov 23 '17 at 19:41
@FirstOne That doesn't generally help with 500 errors, because those are usually syntax errors that prevent anything in the script from running. — Barmar, Nov 23 '17 at 19:42
@Barmar , yes, tried these! did not help. What do you recommend? — Abir Imtiaz, Nov 23 '17 at 19:44
@AbirImtiaz If you didn't see it in the log you must have been looking in the wrong log file. — Barmar, Nov 23 '17 at 19:45

score -1 · Answer 1 · answered Nov 23 '17 at 19:56

-1

Did you try to add true parameter to your json_decode call? I suppose the problem is with the $phone_received param. I also suggest you line by line debugging: try to retrun some dummy result after each line of code step by step so you can detect the place where the error occurs.

answered Nov 23 '17 at 19:56

Azuloo

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2
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that isn't what the question is about; read it over again. – Funk Forty Niner Nov 23 '17 at 20:03
I read it correctly and gave my suggestions. What didn't you like about it? – Azuloo Nov 23 '17 at 20:09
@Fred-ii- Well, my 1st question was about my code which I shared, so I think this comment helped. – Abir Imtiaz Nov 23 '17 at 20:20

What is the proper way to find an 'internal server error 500' in php?

1 Answers1