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Osm Admin: Object Deletion

2022 April Osm Admin

1 month ago ∙ 1 minute read

I implemented the last user action that is typical to a CRUD application - object deletion.

Here is how it went:

HTTP Error 500

I opened Osm Admin project today - and nothing works. All I see is 500 server error. Without any details.

What's going on?

Here is what the Nginx error log file in /var/log/nginx says:

PHP Parse error:  Unclosed '{' on line 611 does not match ')' 
    in /home/vo/projects/admin2/src/Queries/Query.php on line 616

One extra ). Happens.

DELETE /

The last user action is object deletion:

// Osm\Admin\Tables\Routes\Admin\Delete
#[Ui(Admin::class), Name('DELETE /')]
class Delete extends Route
{
    public function run(): Response
    {
        $query = ui_query($this->table->name);

        $query
            ->fromUrl($this->http->query,
                'limit', 'offset', 'order', 'select')
            ->delete();

        return json_response((object)[
            'url' => $this->table->url('GET /'),
        ]);
    }
}

// Osm\Admin\Ui\Query
public function delete(): void {
    foreach ($this->filters as $filter) {
        $filter->queryDb($this->db_query);
    }

    $this->db_query->delete();
}

Delete Notifications Should Not Be Cascade-Deleted

After deleting products, I noticed that product count and the faceted navigation counts are not affected. The only explanation is that the deleted products are not deleted from the search index.

I checked the zi9__products__deletes notification table - it's empty. Ah, they may be deleted with ON DELETE CASCADE rule. Let's change it and re-create the database:

// Osm\Admin\Schema\Indexer
public function createNotificationTables(Table $source): void  {
    if ($deleted = $listensTo[Query::DELETED] ?? null) {
        $this->createNotificationTable($source, $deleted, cascade: false);
    }
}

Delete Notification Should Be Created Before DELETE

CASCADE DELETE rule is gone, and yet the result is the same.

The problem was that I was trying to create a notification after the object is deleted. It's too late to fetch the deleted IDs by then, let's move the notification creation before that:

public function delete(): void {
    $this->db->transaction(function() {
        // create notification records for the dependent objects in
        // other tables, and for search index entries
        $this->notifyListeners(static::DELETED);

        // generate and execute SQL DELETE statement
        $bindings = [];
        $sql = $this->generateDelete($bindings);
        $this->db->connection->delete($sql, $bindings);

        ...
    });
}

Dealing With Async Nature Of Search Index

Everything kind of work, and yet there is one issue left. Just after deleting an object, product count and faceted navigation still doesn't change, but if you refresh the page once again - it does.

Later. The reason is that the page is refreshed before search index is updated. And to solve this issue, I need to wait for product search indexing to happen - and only then refresh the page.