Get the time a custom block was last edited

Question

I have seen lots of answers for getting when a node was last edited, but I can't seem to apply any of these methods to blocks. Basically, I have a block that I only want to display if it has been updated in the last week. When I view blocks in the admin, I see that the admin view shows you when a block was last edited.

I can get my block in hook_preprocess_block, and get things like $block->label(), but any variation of $block->getChangedTime(); or $block->changed; fails for me.

And really, I need this value in my html template, not the block. So I need to get the specific block by ID, in hook_preprocess_html, get the time it was last updated as a unix timestamp, and this would give me the value I need for my twig template.

Answer 1

This is a method of content entities implementing the EntityChangedInterface, like for example node and block_content. In a block template, which is a template of the configured block, you find it in the content array:

if (isset($variables['elements']['content']['#block_content'])) {
  $changed_time = $variables['elements']['content']['#block_content']->getChangedTime();
}

If you want to load the block content entity outside of the block template, see How to get a field value of custom block?

Answer 2

$block->updated should do the trick.