Custom Fields Not Properly Mapped to Desired Types

Custom fields are not being mapped properly when pulling from the returned set of search results. Complex objects don't come back at all and result in the error: Unable to cast object of type 'Newtonsoft.Json.Linq.JObject' to type 'Newtonsoft.Json.Linq.JValue. Because of this it requires developers using the library to map these custom fields on their own.

I did some quick tests in Epinova.ElasticSearch.Core.Engine.SearchEngine.cs, and it seems a small change to the Map function could fix this. My proposed changes for Epinova.ElasticSearch.Core.Engine.SearchEngine.cs is below

private static SearchHit Map(Hit hit)
{
    var searchHit = new SearchHit(hit);

    CustomProperty[] customPropertiesForType = GetCustomPropertiesForType(hit);

    if(!IsValidCustomProperty())
    {
        return searchHit;
    }

    foreach(CustomProperty property in customPropertiesForType)
    {
        if(!hit.Source.UnmappedFields.ContainsKey(property.Name) || property.Type == null)
        {
            continue;
        }

        JToken unmappedField = hit.Source.UnmappedFields[property.Name];

        if(unmappedField == null)
        {
            break;
        }

        searchHit.CustomProperties[property.Name] = unmappedField.ToObject(property.Type);
    }

    return searchHit;

    bool IsValidCustomProperty()
    {
        return customPropertiesForType.Length > 0
            && hit.Source?.UnmappedFields != null
            && hit.Source.UnmappedFields.Any(u => customPropertiesForType.Any(c => c.Name == u.Key));
    }
}

The unit test Query_ReturnsCustomProperties() in Core.Tests.Engine.SearchEngineTests.cs will have to be updated slightly as the casting fails to convert the arrays to IEnumerable\<object>. Here is the slight modification to that unit test to make it pass.

[Fact]
public void Query_ReturnsCustomProperties()
{
    SetupEngineMock("Results_With_Custom_Properties.json");
    var date = DateTime.Parse("2015-03-31T23:01:04.2493062+02:00");
    const string text = "Lorem text";
    const double dec1 = 42.1;
    const long lng1 = 42;
    var arr1 = new long[] { 1, 2, 3 };
    var arr2 = new[] { "Foo", "Bar" };

    Indexing.Instance
        .ForType<TestPage>().IncludeField("Date", _ => date)
        .ForType<TestPage>().IncludeField("Text", _ => text)
        .ForType<TestPage>().IncludeField("Int", _ => lng1)
        .ForType<TestPage>().IncludeField("Dec", _ => dec1)
        .ForType<TestPage>().IncludeField("Array1", _ => arr1)
        .ForType<TestPage>().IncludeField("Array2", _ => arr2);

    SearchResult result = _engine.Query(_dummyQuery, CultureInfo.InvariantCulture);

    Assert.Equal(date, result.Hits.First().CustomProperties["Date"]);
    Assert.Equal(text, result.Hits.First().CustomProperties["Text"]);
    Assert.Equal(lng1, result.Hits.First().CustomProperties["Int"]);
    Assert.Equal(dec1, result.Hits.First().CustomProperties["Dec"]);
    Assert.True(Factory.ArrayEquals(arr1, result.Hits.First().CustomProperties["Array1"] as IEnumerable<long>));
    Assert.True(Factory.ArrayEquals(arr2, result.Hits.First().CustomProperties["Array2"] as IEnumerable<string>));
}

Epinova / Epinova.Elasticsearch

Custom Fields Not Properly Mapped to Desired Types #133