// Protected methods
protected virtual async Task ProcessBatch(List <BatchItem <TKey, TEntity> > batch, CancellationToken cancellationToken)
{
await using var dbContext = CreateDbContext();
var keys = new HashSet <TKey>();
foreach (var item in batch)
{
if (!item.TryCancel(cancellationToken))
{
keys.Add(item.Input);
}
}
var pEntity = Expression.Parameter(typeof(TEntity), "e");
var eKey = KeyExtractorExpressionBuilder.Invoke(pEntity);
var eBody = Expression.Call(Expression.Constant(keys), ContainsMethod, eKey);
var eLambda = (Expression <Func <TEntity, bool> >)Expression.Lambda(eBody, pEntity);
var query = QueryTransformer.Invoke(dbContext.Set <TEntity>().Where(eLambda));
var entities = await query
.ToDictionaryAsync(KeyExtractor, cancellationToken)
.ConfigureAwait(false);
PostProcessor.Invoke(entities);
foreach (var item in batch)
{
entities.TryGetValue(item.Input, out var entity);
item.SetResult(Result.Value(entity) !, CancellationToken.None);
}
}