Extending Search API's query class

Hi, sorry I accidentally left that query.inc empty. The point is to be able to do a custom search query without drupal_alter() and without search_api_current_search(). To find the slider's min/max values, I need to get unaltered "pure" results and these results may not be stored in the Search API system.

So I needed to run a $query->executeClean() like this:

  public final function executeClean() {
    $start = microtime(TRUE);

    // Add filter for languages.
    if (isset($this->options['languages'])) {
      $this->addLanguages($this->options['languages']);
    }

    // Add fulltext fields, unless set
    if ($this->fields === NULL) {
      $this->fields = $this->index->getFulltextFields();
    }

    // Call pre-execute hook.
    $this->preExecute();

    // Preprocess query.
    $this->index->preprocessSearchQuery($this);

    $pre_search = microtime(TRUE);

    // Execute query.
    $response = $this->index->server()->search($this);

    $post_search = microtime(TRUE);

    // Call post-execute hook.
    $this->postExecute($response);

    // Postprocess results.
    $this->index->postprocessSearchResults($response, $this);

    $end = microtime(TRUE);
    $response['performance']['complete'] = $end - $start;
    $response['performance']['hooks'] = $response['performance']['complete'] - ($post_search - $pre_search);

    return $response;
  } 

I removed two lines from execute(():

1. drupal_alter('search_api_query', $this);
Because I need to do a "pure" unalterable query to find min/max values. Otherwise I would end up altering my own min/max query with my search_api_ranges_search_api_query_alter(), but this cannot happen. The min/max queries need to be on a separate track, uninfluenced by anything else.

2. search_api_current_search(NULL, $this, $response);
This makes Search API believe there are multiple searches on the same page, which leads to unwanted behavior. The min/max queries should be considered "stand-alone", not influencing Search API.

You can see what I'm doing in search_api_ranges_minmax_execute(). It looks up the lowest and highest value for a given field, given the current search's keys and filters.

Aha, of course I should just add the function to search_api_ranges.module. I didn't think of that :) Good point about the drupal_alter actually. I'll find another way, like adding a $option['skip_ranges_alter'] = 1 or something like that.

The custom function requires quite a re-write of the original execute() function. I'm trying this now:

function search_api_ranges_minmax_execute(SearchApiQuery $query) {
    $start = microtime(TRUE);

    // Add filter for languages.
    $languages = $query->getOption('languages');
    if (isset($languages)) {
      $query->addLanguages($languages);
    }

    // Add fulltext fields, unless set
    if ($query->getFields() === NULL) {
      $query->fields($query->getIndex()->getFulltextFields());
    }

    // Call pre-execute hook.
    $query->preExecute();

    // Preprocess query.
    $query->getIndex()->preprocessSearchQuery($query);
    
    // Let modules alter the query.
    drupal_alter('search_api_query', $query);

    $pre_search = microtime(TRUE);

    // Execute query.
    $response = $query->getIndex()->server()->search($query);

    $post_search = microtime(TRUE);

    // Call post-execute hook.
    $query->postExecute($response);

    // Postprocess results.
    $query->getIndex()->postprocessSearchResults($response, $query);

    $end = microtime(TRUE);
    $response['performance']['complete'] = $end - $start;
    $response['performance']['hooks'] = $response['performance']['complete'] - ($post_search - $pre_search);

    return $response;
} 

But no luck:
Fatal error: Call to protected method SearchApiQuery::preExecute() from context ''

What would the right approach be?

Thanks, we'll try that as long as it works. Just committed this.