Tools For Better Developers

Framework: Search Hit Limit Must Be Explicit

2022 March Osm Framework

6 months ago ∙ 1 minute read

Wrong Facet Counts In The Blog

Ironically, now when I'm implementing the faceted navigation in Osm Admin, I've noticed that the faceted navigation in my own blog is not working as expected. In the following example: 1 blog post, and then count shows "8":

Wrong Facet Counts

What's going on?

Let's check what's inside the ElasticSearch index.

It turns out, a given blog post was added to the index 8 times. In osm.software blog, I update the index with either osm index:blog or osm index:blog -f commands (Osm Admin uses the same approach). -f option clears the index, and add all entries anew:

    foreach ($this->search->index('posts')->ids() as $id) {
        $this->search->index('posts')->delete($id);
    }

And here is a problem. By default, if not entry limit is specified, ElasticSearch returns only the first 10 entries. So the osm index -f doesn't delete all records, but just the first 10 ones!

For now, let's just add the big enough limit() call:

    $ids = $this->search->index('posts')->limit(10000)->ids();

    foreach ($ids as $id) {
        $this->search->index('posts')->delete($id);
    }

Fixing Implicit Search Limit In Osm Framework

The implicit ElasticSearch hit limit is confusing. And you can't get all the hits - there is 10000 maximum hit limit that you can't exceed even explicitly.

Let's throw an exception if some other code tries to retrieve search index data without setting the limit:

// ElasticSearch/Query.php
protected function paginateElasticQuery(array $request): array {
    ...
    if ($this->limit !== null) {
        $request['body']['size'] = $this->limit;
    }
    else {
        throw new InvalidQuery(__("Call 'limit()' before retrieving data from the search index"));
    }
    ...
}