Show custom product field in new order email - woocommerce

Question

i created a custom field in a product called course-date. I asissnged it a date e.g Jan 30. This is what I have in the email yet nothing shows.. am i missing something? code edited with new snippet below
<?php
/**
* Customer processing order email
*
* #author WooThemes
* #package WooCommerce/Templates/Emails
* #version 2.4.0
*/
if ( ! defined( 'ABSPATH' ) ) {
exit; // Exit if accessed directly
}
?>
<?php
$items = $order->get_items();
foreach ( $items as $item ) {
$product_name = $item['name'];
$product_id = $item['product_id'];
$product_variation_id = $item['variation_id'];
$course_date=get_post_meta($product_id, 'course-date', true);
//Note $course_date will get overwritten if there are more than one items in the order.
}
?>
<?php do_action('woocommerce_email_header', $email_heading); ?>
<p>This email is to notify you of your recent registration for the <b>Level 1 - Think and Grow Rich Institute Course</b>!</p>
<p>You are registered to attend on:</p>
<p><?php printf( __( '<b>Registration ID:</b> %s', 'woocommerce' ), $order->get_order_number() ); ?></p>
<p><b>Course Registration Date:</b> <?php echo get_post_meta($post->id, 'course-date', true); ?></p>
<p><b>Time:</b> 8am Registration - 9am Event Begins (See Full Schedule)</p>
<p><b>Location:</b> 240 Belfield Rd, Toronto, ON M9W 1H3</p>
<p>If you have any questions please contact us by e-mail: contact#thinkandgrowrichinstitute.com.</p>
<p>Sincerely,<BR/>
The Think and Grow Rich Institute Team</p><BR/>
<p><em><b>"Whatever The Mind Can Conceive and Believe, It Will Achieve."</b> - Napoleon Hill</em></p>
<?php do_action( 'woocommerce_email_before_order_table', $order, $sent_to_admin, $plain_text ); ?>
<?php do_action( 'woocommerce_email_after_order_table', $order, $sent_to_admin, $plain_text ); ?>
<?php do_action( 'woocommerce_email_order_meta', $order, $sent_to_admin, $plain_text ); ?>
<?php do_action( 'woocommerce_email_customer_details', $order, $sent_to_admin, $plain_text ); ?>
<?php do_action( 'woocommerce_email_footer' ); ?>

Answer 1

Hope you get to learn more from this answer and it adds to you knowledge of WooCommerce.
For the Snippet you sent of the "Customer processing order email".
The system is unable to find the value of $_product->id here. So it is not working.
You have to debug it by print the Product id itself in the initial test emails.
If you are unable to get the product id. Here is a bit more information.
An order may have more than one products. So finding the product with the meta fields can be troublesome especially when you are having a question of which product you should show the meta field of.
Easy way is to use the given object $order retrieve the order id from this object then find all the products associated in this order and then find meta field value for those products.
<?php
$items = $order->get_items();
foreach ( $items as $item ) {
$product_name = $item['name'];
$product_id = $item['product_id'];
$product_variation_id = $item['variation_id'];
$course_date=get_post_meta($product_id, 'course-date', true);
if(isset($course_date) && $course_date!=""){
echo "<p><b>Course Registration Date:</b>".$course_date."</p>";
}
}
?>
Let us know whether this gave you any insight of the issue.

Answer 2

Here's an untested example of how to add a string to the "customer_processing_email" without overriding the template. You would add this code to your theme's functions.php and the text should appear prior to the order table.
add_action( 'woocommerce_email_order_details', 'kia_custom_order_details', 5, 4 );
function kia_custom_order_details( $order, $sent_to_admin, $plain_text, $email ){
if( $email->id == "customer_processing_order" ){
$course_date = null;
// borrowing the loop from WisdmLabs's answer
$items = $order->get_items();
foreach ( $items as $item ) {
$product_name = $item['name'];
$product_id = $item['product_id'];
$product_variation_id = $item['variation_id'];
$course_date = get_post_meta($product_id, 'course-date', true);
if( $course_date != '' ) break; //break out of the loop if we find a course date
}
if( $course_date && $plain_text ){
echo "Course Registration Date: " . $course_date . "\n\n";
} else if( $course_date && ! $plain_text ){
echo "<p><b>Course Registration Date:</b> " . $course_date . "</p>" . "/n/n";
}
}
}
Don't forget the different formatting for rich text versus plain text emails. I left most of the formatting for the rest of your text to you as the important part was finding/printing the course date meta.
I still think that using a separate email would be the best approach here, but as far as I can tell you were only missing echoing out $course_date in the right place.