I’m trying to create a plugin using FPDF to create an options page to print custom post types.
Here is my code:
<?php
/*
* Plugin Name: RT FPDF Tutorial
* Description: A plugin created to demonstrate how to build a PDF document from WordPress posts.
* Version: 1.0
*/
if ( ! defined( 'ABSPATH' ) ) {
exit;
}
include( 'pdf-helper-functions.php');
$pdf = new PDF_HTML();
if( isset($_POST['generate_posts_pdf'])){
output_pdf();
}
add_action( 'admin_menu', 'rt_fpdf_create_admin_menu' );
function rt_fpdf_create_admin_menu() {
$hook = add_submenu_page(
'tools.php',
'PDF Generator',
'PDF Generator',
'manage_options',
'rt-fdpf-tutorial',
'rt_fpdf_create_admin_page'
);
}
function rt_fpdf_create_admin_page() {
echo '<div class="wrap">';
echo ' <form method="post" id="as-fdpf-form"><button class="button button-primary" type="submit" name="generate_posts_pdf" value="generate">Generate the Directory</button></form>';
echo '</div>';
}
function output_pdf() {
global $pdf;
$title_line_height = 10;
$content_line_height = 8;
$args = array(
'post_type' => 'cc_family',
);
// The Query
//$the_query = new WP_Query( array ('post_type' => 'cc_family') );
$pdf->AddPage();
$pdf->SetFont( 'Arial', '', 42 );
$pdf->Write(20, 'No families to make a directory yet');
$pdf->Output('D','new-directory.pdf');
exit;
}
As the code is right now it works ($the_query is commented out.) A pdf is created with the content "no families…".
If I un-comment the line above to start adding the query, I get a critical error on my site. If I add an entire generic query I get an error as well.
I’ve tried with get_posts() and this works, but it doesn’t seem to allow me to pull custom fields. Is there something special to adding a new query I’ve missed?
Update to add the error:
> [13-Sep-2021 15:30:51 UTC] PHP Notice: ob_end_flush(): failed to send
> buffer of zlib output compression (0) in
> /home/whn/public_html/wp-includes/functions.php on line 5107
> [13-Sep-2021 15:30:53 UTC] PHP Fatal error: Uncaught Error: Call to
> undefined function is_user_logged_in() in
> /home/whn/public_html/wp-includes/class-wp-query.php:2544 Stack
> trace:
> #0 /home/whn/public_html/wp-includes/class-wp-query.php(3465): WP_Query->get_posts()
> #1 /home/whn/public_html/wp-includes/class-wp-query.php(3576): WP_Query->query(Array)
> #2 /home/whn/public_html/wp-content/plugins/pdfer/rt_pdf.php(48): WP_Query->__construct(Array)
> #3 /home/whn/public_html/wp-content/plugins/pdfer/rt_pdf.php(18): output_pdf()
> #4 /home/whn/public_html/wp-settings.php(409): include_once('/home/wh3n/publ...')
> #5 /home/whn/public_html/wp-config.php(91): require_once('/home/wh3n/publ...')
> #6 /home/whn/public_html/wp-load.php(50): require_once('/home/wh3n/publ...')
> #7 /home/whn/public_html/wp-admin/admin.php(34): require_once('/home/wh3n/publ...')
> #8 /home/whn/public_html/wp-admin/tools.php(40): require_once('/home/wh3n/publ...')
> #9 {main} thrown in /home/whn/public_html/wp-includes/class-wp-query.php on line 2544
> [13-Sep-2021 15:30:53 UTC] PHP Notice: is_embed was called
> <strong>incorrectly</strong>. Conditional query tags do not work
> before the query is run. Before then, they always return false. Please
> see <a
> href="https://wordpress.org/support/article/debugging-in-wordpress/">Debugging
> in WordPress</a> for more information. (This message was added in
> version 3.1.0.) in /home/whn/public_html/wp-includes/functions.php on
> line 5663 [13-Sep-2021 15:30:53 UTC] PHP Notice: is_search was called
> <strong>incorrectly</strong>. Conditional query tags do not work
> before the query is run. Before then, they always return false. Please
> see <a
> href="https://wordpress.org/support/article/debugging-in-wordpress/">Debugging
> in WordPress</a> for more information. (This message was added in
> version 3.1.0.) in /home/whn/public_html/wp-includes/functions.php on
> line 5663 [13-Sep-2021 15:30:54 UTC] PHP Notice: ob_end_flush():
> failed to send buffer of zlib output compression (0) in
> /home/whn/public_html/wp-includes/functions.php on line 5107
