How to get Node contents

[natanfelles]

Hello!

I need to get the content of paragraphs to add classes to them.

This is my basic configuration:

'default_attributes' => [
    Paragraph::class => [
        'class' => static function (Paragraph $node) {
            $content = $node->getContent(); // Method does not exist
            if (str_starts_with($content, 'danger:')) {
                return 'alert alert-danger';
            }
            return null;
        },
    ],
]

Thank you very much!

[colinodell]

Hi there!

TL;DR: Use $content = StringContainerHelper::getChildText($paragraph);

Paragraph nodes do not directly contain text, but some of their descendants do. Here's an example of such an AST (visualized as XML):

<document>
  <heading level="1">
    <text>Hello World!</text>
  </heading>
  <paragraph>
    <text>This is an example of </text>
    <strong>
      <text>CommonMark</text>
    </strong>
    <text>.</text>
  </paragraph>
</document>

To find that text, you'd need to iterate through those nodes, looking for any that implement StringContainerInterface, and concatenating what those contain.

Or you can use this helper function which does exactly that for you :)

[natanfelles]

Thank you @colinodell !

The following snippet works for me:

'default_attributes' => [
    Paragraph::class => [
        'class' => static function (Paragraph $node) {
            foreach ($node->iterator() as $child) {
                if ($child instanceof StringContainerInterface) {
                    $text = $child->getLiteral();
                    if (str_starts_with($text, 'danger:')) {
                        $child->setLiteral(trim(substr($text, 7)));
                        return 'alert alert-danger';
                    }
                    return null;
                }
            }
        },
    ],
]