Global filters - Run it before template loads

Kirby 2 Suggestions đź’ˇ
1

I think the idea of filters that are global could be a good idea.

Current way

To every query on the whole site, with some plugins, we need to exclude some pages, like revisions or modules.

foreach($page->children()->not('revisions')->not('modules') as $child) {
  echo $child->title();
}

The future way

Global filter

It can be set with a plugin.

global::$filters['unique-id'] = function($collection, $field, $value) {
  // Some filtering
  return $collection;
};

Because a global filter is used, not all children will be listed. Some are sorted out (revisions and modules in this case) without the need to exclude them in the template.

foreach($page->children() as $child) {
  echo $child->title();
}

What do you think? If you see pitfalls, which are they? If you have other ideas of how to solve this (probably growing) problem, share your ideas. :slight_smile:

2

Unfortunately this won’t work. Filtering out pages completely means that even Kirby doesn’t see them anymore. They won’t be listed in the Panel, the Modules/Revisions plugins wouldn’t be able to access them anymore etc.
What we could do (just thinking out loud) is to offer some kind of “filter template”:

collection::$filterTemplates['no-modules'] = function($collection) {
  return $collection->not('modules');
};

foreach($page->children()->filterByTemplate('no-modules') as $child) {
  echo $child->title();
}

It works kind of like the existing $collection->filter($callback) method except that it isn’t called on every item but instead in a more natural “just return some kind of new collection” way.

3

Wouldn’t it be easier in that case just to add a custom pages method which filters out all “not real” pages? And also the shortest in syntax if you choose a short name?

4 
pages::$methods['real'] = function($pages) {
    return $pages->filterBy('intendedTemplate', 'not in', ['module', 'revision']);
};

Or even combine it as page method:

page::$methods['realChildren'] = function($page) {
    return $page->children()->filterBy('intendedTemplate', 'not in', ['module', 'revision']);
};
4 Likes
5

Good point! It can’t be applied to collections, but for pages it’s an awesome solution.

6

It’s not the final solution as it has some pitfalls, but it’s the best workaround I’ve seen. :slight_smile: I had to add it to https://github.com/jenstornell/kirby-secrets/wiki/Global-collection-filter