public async Task <IStreamMergeAsyncEnumerator <T> > GetStreamEnumerator()
{
var enumeratorTasks = _mergeContext.RouteResults.Select(routeResult =>
{
return(Task.Run(async() =>
{
var shardingDbContext = _mergeContext.CreateDbContext();
_parallelDbContexts.Add(shardingDbContext);
var newQueryable = (IQueryable <T>)_mergeContext.GetReWriteQueryable().ReplaceDbContextQueryable(shardingDbContext);
var asyncEnumerator = await GetAsyncEnumerator(newQueryable, routeResult);
return new StreamMergeAsyncEnumerator <T>(asyncEnumerator);
}));
}).ToArray();
var streamEnumerators = await Task.WhenAll(enumeratorTasks);
if (_mergeContext.HasSkipTake())
{
return(new NoPaginationStreamMergeEnumerator <T>(_mergeContext, streamEnumerators));
}
if (_mergeContext.HasGroupQuery())
{
return(new MultiAggregateOrderStreamMergeAsyncEnumerator <T>(_mergeContext, streamEnumerators));
}
return(new MultiOrderStreamMergeAsyncEnumerator <T>(_mergeContext, streamEnumerators));
}
public NoPaginationStreamMergeEnumerator(StreamMergeContext <T> mergeContext, IEnumerable <IStreamMergeAsyncEnumerator <T> > sources)
{
_mergeContext = mergeContext;
_skip = mergeContext.Skip;
_take = mergeContext.Take;
if (_mergeContext.HasGroupQuery())
{
_enumerator = new MultiAggregateOrderStreamMergeAsyncEnumerator <T>(_mergeContext, sources);
}
else
{
_enumerator = new MultiOrderStreamMergeAsyncEnumerator <T>(_mergeContext, sources);
}
}