Optimizely Search & Navigation: Boosting in Unified Search

In the Optimizely Search & Navigation admin view, administrators can set a certain weight of different properties (title, content, summary, or document content). When an user searches for a keyword that matches to a property’s value, the higher weight of that property will make the matching pages to be more likely to appear at the top of the search result.

Once you configured the weights, you can boost scores by calling a standard Unified Search method – UnifiedSearchFor:

var result = client.UnifiedSearchFor(searchText).GetResult();

Or calling UsingUnifiedWeights() with no parameters. This can also boost the scores based on the admin-defined weights.

var result = client.UnifiedSearch(Language.English).For(searchText).UsingUnifiedWeights().GetResult();

The problem:

Choosing a Global Software Development Partner to Accelerate Your Digital Strategy

To be successful and outpace the competition, you need a software development partner that excels in exactly the type of digital projects you are now faced with accelerating, and in the most cost effective and optimized way possible.

Get the Guide

However, in real life scenarios, those 4 out-of-the-box property weights in admin view are obviously not enough. For example, we want to boost the Author’s name of the Article Page when using search. How can we do that?

The solution:

Well, since these settings are not extensible, the work-around for this is using Boost with Filters for your search query. We will use BoostMatching extenstion method to boost the score of hits based on certain criteria, something like this:

query = query.BoostMatching(x => x.Author.MatchCaseInsensitive(searchText), 2);

This snippet above will work for a type-specific search. But in an unified search, where we search for multiple types and results are ISearchContent objects, we need an extra step:

query = query.BoostMatching(x => x.MatchTypeHierarchy(typeof(ArticlePage)) & ((ArticlePage)x).Author.MatchCaseInsensitive(searchText), 2);

The above will only boost ArticlePage that Author name matches the search text, other page types will be ignored in this boosting condition. And the boost weight of that matching condition is 2. According to the documentation, “The default property weight, 1, does not affect the score. A weight above 1 boosts the score if the information is in a corresponding property. A weight smaller than 1 reduces the score”.

You can wrap several boosting conditions into a search extension and call it from anywhere.

public static IQueriedSearch<ISearchContent, CustomFiltersScoreQuery> ApplyUnifiedSearchBoosting(this ITypeSearch<ISearchContent> baseSearchQuery, string searchText)
{
      return baseSearchQuery
            .BoostMatching(x => x.MatchTypeHierarchy(typeof(ArticlePage)) & ((ArticlePage)x).Author.AnyWordBeginsWith(searchText), 2)
            .BoostMatching(x => x.MatchTypeHierarchy(typeof(ProductPage)) & ((ProductPage)x).ProductCode.MatchCaseInsensitive(searchText), 4);
}

Ultimately, you can store your own weight values in your appsettings or in the CMS. I would prefer to store it in some kinds of Settings Page so they can be configurable.