PHP MAIL: one of my variables send a "false" value - php

Question

I am sending an e-mail with different variables as an JSON encoded array from an online store. I get the mail just fine and all the data is in there except for one of the variables, which is a JSON encoded array by itself. this particular variable shows as "false" in the e-mail. I'm missing something?
I'm using PHP mail to do it.
<?php
require_once "Mail.php";
$link = mysqli_connect("localhost", "xxx", "xxx", "xxx");
if ($link === false) {
die("ERROR: Could not connect. " . mysqli_connect_error());
}
$sql = "SELECT * FROM users WHERE user = '" . $_SESSION['logged'] . "'";
$result = mysqli_query($link, $sql);
$row = mysqli_fetch_assoc($result);
$user = $_SESSION['logged'];
$rua = $_POST['rua'];
$numero = $_POST['numero'];
$apt = $_POST['apt'];
$cep = $_POST['cep'];
$total = $_POST['total'];
$comment = $_POST['observacion'];
$from = $row['mail'];
$mailTo = "xxxxx#hotmail.com";
$subject = "compra online - no cep";
$compra = $_SESSION["shopping_cart"];
$compra2 = json_encode($compra);
$bod = array(
'user' => $user,
'rua' => $rua,
'cep' => $cep,
'compra' => $compra2,
'comment' => $comment,
'total' => $total,
);
$body = json_encode($bod);
$headers = array(
'From' => $from,
'To' => $mailTo,
'Subject' => $subject,
);
$smtp = Mail::factory('smtp', array(
'host' => 'smtp-mail.outlook.com',
'port' => '587',
'auth' => true,
'username' => 'xxxxxxx#hotmail.com',
'password' => 'xxxxxxx',
));
$mail = $smtp->send($mailTo, $headers, $body);
if (PEAR::isError($mail)) {
echo ("<p>" . $mail->getMessage() . "</p>");
} else {
header("Location: lojacart.php?mailok");
}
mysqli_close($link);
I'm getting the e-mail with all the data except for the $compra2 variable which is showing as 'compra'=false. now if I echo the variable $compra2 it actually have a large string of data on it.
I think it might have to do with the variable being a JSON encoded session, but I'm not sure.

Answer 1

After a lot of trying and getting frustrated I came with a solution, for those looking for a something like this:
I added a hidden input to the form on the previous page and assigned it a value as "print_r($SESSION['whatever you session is called'], TRUE)" ...
on the next page I took the $_POST[] form that input and added the variable to the $body array for the mail().
It will print some array garbage in the middle BUT it works like a charm! and I cleaned all the "extra" text form the array using preg_replace(). It may not be an elegant way of doing it but as I said... it worked