Couchbase.Lite.Mapping plugin

Mobile Couchbase Lite
1

I’ve started using the plugin: Couchbase.Lite.Mapping for binding my model and database documents together. I really appreciate the effort put into this by Rob Hedgpeth. However, I have a challenge trying to put a “group by” query’s results into a list of models with just a couple of properties.

Not sure if this is the best place to ask - but thought there is a good “concentration” of Couchbase people here - so someon may know.

So this is my generic GetList method with special handling for model DataEntity:

            var list = new List<T>();
            // Special handling for DataEntity
            if (string.Equals(typeof(DataEntity).Name, typeof(T).Name))
            {
                using (var query = QueryBuilder.Select(
                        SelectResult.Expression(Function.Count(Expression.All())).As("count"),
                        SelectResult.Property("type"))
                       .From(dbSource)
                       .Where(Expression.Property("type").NotNullOrMissing())
                       .GroupBy(Expression.Property("type"))
                       .OrderBy(Ordering.Property("type").Ascending()))
                {
                    var result = query?.Execute()?.AllResults();
// This works - but does not using the mapping module....
                    foreach (var record in result)
                    {
                        var d = new DataEntity();
                        d.Count = record.GetInt(COUNT);
                        d.Type = record.GetString(TYPE);
                        list.Add((T)(object)d);
                    }
// This, however, crashes the app with
// Newtonsoft.Json.JsonReaderException: Error reading JObject from JsonReader. Current JsonReader item is not an object: Null. 
                    //var items = result?.ToObjects<T>(AppConstants.DB_NAME);
// This crashes with an error that key cannot be null
                    //var items = result?.ToObjects<T>(null);
                    //list.AddRange(items);
                }
            }
          :

I guess the problem lies in the fact that there is no “root” element (being the bucket name).

Does anyone know if I somehow can use the mapping plugin to get results like this into a list of objects instead of having to do it manually?

2

Thanks for this feedback, @jda! This is the perfect place for it.

Unfortunately (and fortunately too) you’ve found a gap in functionality using Couchbase.Lite.Mapping. Would you mind creating an issue here? That’ll give me something to attach the changes too, and make sure you get an update as soon as I’ve made the fixes.

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