Read content of uploaded PDF file and save it ACF field

• esedic

• April 13, 2023 at 9:15 am

I have a custom post type “movies” with ACF file upload field called “document_file”. I would like to save the content of the uploaded PDF document to another ACF textarea field called “document_content”. I have a working PHP code using XPDF binaries and a PHP library, that reads PDF content and returns a string with this content.

I’m using following code to update ACF field:

function set_field_value( $post_id ) {
    global $post;
    $post_id = $post->ID;
    $posttype = get_post_type($post_id);
    $value = 'some sample text'; // this should be a string which we get from uploaded pdf documentcontent 

    $document_content = get_field('document_content', $post_id);

    if ($posttype == 'movies' & empty($document_content)) {
        update_field('document_content', $value, $post_id);
    }
}
add_action('acf/save_post', 'set_field_value');

This works, but I would like to pass a $value variable from a function attached to file upload hook to a function set_field_value() in acf/save_post hook, but I’m not sure how to do it – which hook to use on ACF file upload. Example function, which reads PDF content:

function read_pdf_content( $post_id ) {
    require __DIR__ . '/vendor/autoload.php';
    $logger = null;

    $document_file = get_field('document_file', $post_id);

    if( $document_file ) {
    
        $pdfToText = XPDF\PdfToText::create(array(
                'pdftotext.binaries' => '../../../../usr/bin/xpdf/bin64/pdftotext'
            ), $logger);

        $document_content_txt = $pdfToText->getText($document_file['filename']);
        // remove non-latin characters
        $pdf_content = preg_replace('/[^\00-\255]+/u', '', $document_content_txt);

        //update_field('document_content', $pdf_content, $post_id);
    } else {
        $pdf_content = '';
    }

    return $pdf_content;
}

So in this case I would like to pass $pdf_content variable to acf/save_post’ hook, so I could save it in ACF field called ‘document_content’.

Is wp_handle_upload hook a way to go?

Regards.

• John Huebner

• April 18, 2023 at 3:10 pm

change

$document_file = get_field('document_file', $post_id);

to

$document_file = get_attachment_file(get_field('document_file', $post_id, false));

setting the last parameter false for ACF gets the unformatted value, in this case the attachment ID. The WP function get_attachment_file() loads that file into the variable. Then you can pass this to convert it to text.

Then you call update_field() to update the text field with what is returned.