Showing Image Thumbnails in AjaxSearch Results with a Custom PHx Modifier

One common AjaxSearch customization is to show a thumbnail next to every search result. The catch is that the image is not always stored in a TV, and sometimes the file may not exist at all. In that case the result template needs a safe condition instead of a blind <img> tag.

The Original Pattern

The legacy topic used a result template that tried to build the image path from the resource ID and then pass it through a custom PHx modifier:

<div class="[+as.resultClass+]">

    [+phx:`/assets/images/thumbs/[+as.id+]_small.jpg`:file_exists+]

    <a class="[+as.resultLinkClass+]" href="[+as.resultLink+]" title="[+as.longtitle+]">[+as.pagetitle+]</a>
    [+as.descriptionShow:is=`1`:then=`
      <span class="[+as.descriptionClass+]">[+as.description+]</span>
    `+]
    [+as.extractShow:is=`1`:then=`
      <div class="[+as.extractClass+]"><p>[+as.extract+]</p></div>
    `+]
    [+as.breadcrumbsShow:is=`1`:then=`
      <span class="[+as.breadcrumbsClass+]">[+as.breadcrumbs+]</span>
    `+]
    <div class="clear"></div>
</div>

The custom modifier itself looked like this:

<?php
/*
 * description: Check if file exists
 * usage: [+filename:file_exists=`String to return if exists`+]
 */
$url = trim($output);
$output = $modx->config['base_path'] . $url;
if (file_exists($output)) {
    return 'EXIST';
}
return 'NOT EXIST';

Why This Often Fails in AjaxSearch

AjaxSearch runs its own parser flow for result placeholders. If you bolt a PHx modifier into the template, the modifier may run, but the value can still be overwritten later in AjaxSearch output processing. That makes the final result look empty even though the file check itself worked.

A More Reliable Approach

If you need this behavior in production, the safer option is to calculate one explicit result field before the final template is rendered. In practice that means one of two things:

• extend the AjaxSearch parser with a dedicated modifier case such as imgexists
• prepare the full image markup in PHP and output a ready-made placeholder instead of stacking parser layers

The legacy discussion even tried a direct parser case like this:

case 'imgexists':
    if ($output != '' && file_exists($modx->config['base_path'] . $output)) {
        $output = 1;
    } else {
        $output = 0;
    }
    break;

Practical Recommendation

For maintainable search results, keep the rule simple: build the path, check it once in PHP, and expose either a ready imageUrl or a ready thumbnailHtml placeholder to the result template. That is easier to debug than chaining PHx inside AjaxSearch internals.

If you still prefer the PHx route, test directly inside assets/snippets/ajaxSearch/classes/asPhxParser.class.inc.php and verify that no later step resets the placeholder value.