Search

//if the result does not make sense, show error message
//(note that there may still be results!)
if (!$response->getValue("MakesSense"))
    echo "We did not understand your query.";

//render spelling suggestions
if($response->hasData("SpellingSuggestions"))
{
    $suggestions = $response->getCollection("SpellingSuggestions");
    if(count($suggestions)>0)
        echo "Did you mean: ";

    foreach($suggestions as $suggestionItem)
    {
        echo $suggestionItem->key . " ";
    }
}

Best practice

Paging

Display 20-30 direct hits on the landing page, with the option to continue to page 2, 3 etc.

Results above the fold

Make sure the user does not have to scroll to reach the actual product results. At least 1, but preferably 2, rows of results should be visible above the fold after a search.

The search field

Keep the search query in the search field, even after the user has performed the search. This serves as a form of breadcrumb and makes it far easier for the user to refine their query.

//initialize "Search" request
$request = new Loop54_Request("Search");

//set search query
$request->setValue("QueryString",$_GET{"query"});

//specify number of response items
$request->setValue("DirectResults_FromIndex",0);
$request->setValue("DirectResults_ToIndex",9);
$request->setValue("RecommendedResults_FromIndex",0);
$request->setValue("RecommendedResults_ToIndex",9);

//fetch response from engine
$response = Loop54_RequestHandling::getResponse("http://helloworld.54proxy.com", $request);

//successful response
if ($response->success)
{
    //if the result does not make sense, show error message
    //(note that there may still be results!)
    if (!$response->getValue("MakesSense"))
        echo "We did not understand your query.";

    //render spelling suggestions
    if($response->hasData("SpellingSuggestions"))
    {
        $suggestions = $response->getCollection("SpellingSuggestions");
        if(count($suggestions)>0)
            echo "Did you mean: ";

        foreach($suggestions as $suggestionItem)
        {
            echo $suggestionItem->key . " ";
        }
    }

    //render direct results
    if($response->hasData("DirectResults"))
    {
        $results = $response->getCollection("DirectResults");
        if(count($results)==0)
            echo "There were no items matching your search.";

        foreach($results as $resultItem)
        {
            $productId = $resultItem->key->externalId;
            $productTitle = $resultItem->key->getStringAttribute("Title");
            echo $productId . " " . $productTitle; //render a product on the search results page
        }
    }

    //render recommended results
    if($response->hasData("RecommendedResults"))
    {
        $results = $response->getCollection("RecommendedResults");
        if(count($results)>0)
            echo "Maybe you also want these?";

        foreach($results as $resultItem)
        {
            $productId = $resultItem->key->externalId;
            $productTitle = $resultItem->key->getStringAttribute("Title");
            echo $productId . " " . $productTitle; //render a product on the search results page
        }
    }
}
else
{
    echo $response->requestId; //log this
}