Exemple #1
0
        public static IProjectionAttribute ValList(this IProjection projection, Func <IProjectionAttribute, IProjectionAttribute> itemFactory)
        {
            if (projection.Data == null)
            {
                throw ProjectionException.ValueNotFound(projection.Metadata);
            }

            IProjectionMetadata itemMetadata = projection.Metadata?.Item ?? projection.Metadata;

            using ProjectionReader reader = new ProjectionReader(projection.Data.Source, new[] { itemMetadata });

            IProjectionAttribute attribute = new ProjectionAttribute(projection.Identity, projection.Context, itemMetadata, data: null);

            if (reader.Read())
            {
                IProjectionData data = reader.GetData().First();

                attribute = itemFactory(attribute.With(data: data));
            }

            while (reader.Read())
            {
                IProjectionData data = reader.GetData().First();

                attribute = attribute.Append(", ");
                attribute = itemFactory(attribute.With(data: data));
            }

            return(attribute);
        }
Exemple #2
0
        public static IProjectionValues <TModel> Vals <TModel>(this IProjection <TModel> projection, int batchIndex = -1)
        {
            if (projection.Data == null)
            {
                throw ProjectionException.ValueNotFound(projection.Metadata);
            }
            else if (projection.Data.Source.Snapshot == null)
            {
                IEnumerable <IProjection <TModel> > emptyItems = Array.Empty <IProjection <TModel> >();

                return(new ProjectionValues <TModel>(projection.Context, projection.Identity, emptyItems, batchIndex));
            }

            IProjectionMetadata[]  header = new[] { projection.Metadata }.Concat(projection.Header.Select(a => a.Metadata)).ToArray();
            IProjectionAttribute[] attributes = header.Skip(1).Select(m => new ProjectionAttribute(projection.Identity, projection.Context, m, data: null)).ToArray();

            return(new ProjectionValues <TModel>(projection.Context, projection.Identity, innerReader(), batchIndex));

            IEnumerable <IProjection <TModel> > innerReader()
            {
                using ProjectionReader reader = new ProjectionReader(projection.Data.Source, header);

                while (reader.Read())
                {
                    IProjectionData[] dataSet = reader.GetData().ToArray();

                    if (dataSet[0].Source.Snapshot != null)
                    {
                        IEnumerable <IProjectionAttribute> valueHeader = attributes.Zip(dataSet.Skip(1)).Select(t => t.First.With(data: t.Second));

                        yield return(projection.With(data: dataSet[0], header: valueHeader));
                    }
                }
            }
        }