Weighted Examine Search

weightedExamineSearch

/// <summary>
/// List of products, ordered by weight
/// </summary>
/// <param name="searchTerm"></param>
/// <param name="maxItems"></param>
/// <param name="pageNumber"></param>
/// <param name="memberTypeIds"></param>
/// <param name="pagingInfo"></param>
/// <returns>List of SearchResultItems</returns>
public IList<BaseProduct> SearchProducts(string searchTerm, int maxItems, int pageNumber, IList<int> memberTypeIds, out PagingInfo pagingInfo)
{
    var memberType = MemberType.Retail;

    if (memberTypeIds.HasItemsAndNotNull())
        memberType = (MemberType)memberTypeIds.FirstOrDefault();

    pagingInfo = new PagingInfo();

    if (String.IsNullOrEmpty(searchTerm))
        return null;

    var searchProvider = ExamineManager.Instance.SearchProviderCollection["ProductAndVariationSearcher"];
    var criteria = ExamineManager.Instance.SearchProviderCollection["ProductAndVariationSearcher"].CreateSearchCriteria();

    // Terms and weight
    var fields = new Dictionary<string, int>
    {
        //get proper field names in here
        {"DisplayName", 10}, 
        {"SKU", 10}, 
        {"UPC", 10},
        {"ShortDescription", 1}, 
        {"Description", 1}
    };

    // Multipliers for match types. We want to give more weight to exact matches
    const int exactMatch = 5;
    const int termMatch = 2;

    var fieldQuery = new StringBuilder();
    var splitSearch = searchTerm.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);

    // Build field query
    foreach (var field in fields)
    {
        // Full exact match (which has a higher boost)
        fieldQuery.Append(string.Format("{0}:{1}^{2}", field.Key, "\"" + searchTerm.EscapeForLucene() + "\"", field.Value * exactMatch));
        fieldQuery.Append(" ");

        // NOTE: Phrase match wildcard isn't really supported unless you use the Lucene
        // API like ComplexPhraseWildcardSomethingOrOther...

        // Split match
        foreach (var s in splitSearch)
        {
            //match on each term, no wildcard, higher boost
            fieldQuery.Append(string.Format("{0}:{1}^{2}", field.Key, s.EscapeForLucene(), field.Value * termMatch));
            fieldQuery.Append(" ");

            //match on each term, with wildcard 
            fieldQuery.Append(string.Format("{0}:{1}*", field.Key, s.EscapeForLucene()));
            fieldQuery.Append(" ");
        }
    }

    var rawQueryString = String.Format("+nodeTypeAlias:({0}) AND +search_memberTypeIds:({1}) AND +({2}) AND +search_notDirectlyPurchasable:0", "Product ProductVariation", String.Join(" ", memberTypeIds), fieldQuery);

    criteria.RawQuery(rawQueryString);

    var results = searchProvider.Search(criteria);

    pagingInfo = PagingHelpers.GetPagingInfo(results.Count(), maxItems, pageNumber);

    var products = _umbracoHelper.TypedContent(results.Select(x => x.Id))
           .GetPagedItems(pageNumber, maxItems)
           .ConvertToTypedList<BaseProduct>();

    foreach (var result in products)
    {
        var searchResult = results.FirstOrDefault(x => x.Id == result.Id);
        result.PriceMatrix = new PriceRangeMatrix()
        {
            MinRetailPrice = searchResult.GetDecimalValueSafelyByKey("search_min_retailPrice"),
            MaxRetailPrice = searchResult.GetDecimalValueSafelyByKey("search_max_retailPrice"),
            MinDropshipPrice = searchResult.GetDecimalValueSafelyByKey("search_min_dropShipPrice"),
            MaxDropshipPrice = searchResult.GetDecimalValueSafelyByKey("search_max_dropShipPrice"),
            MinGovernmentPrice = searchResult.GetDecimalValueSafelyByKey("search_min_governmentPrice"),
            MaxGovernmentPrice = searchResult.GetDecimalValueSafelyByKey("search_max_governmentPrice"),
            MinTradePrice = searchResult.GetDecimalValueSafelyByKey("search_min_tradePrice"),
            MaxTradePrice = searchResult.GetDecimalValueSafelyByKey("search_max_tradePrice"),
            MinWholesalePrice = searchResult.GetDecimalValueSafelyByKey("search_min_wholesalePrice"),
            MaxWholesalePrice = searchResult.GetDecimalValueSafelyByKey("search_max_wholesalePrice"),
        };
    }

    return products;
}