public static IObservableQuery <Continuation <T[]>, TFilter> CreateQueryableStore <T, TFilter, TEvent>(this IObservable <TEvent> stream, Func <T[]> store, ISubject <TFilter> filterStream, Func <TFilter, T, bool> filerFunc, ContinuationToken token, Func <TEvent, bool> updateWhen, IScheduler scheduler = null)
{
var storeObs = stream.Where(updateWhen).Select(_ => store());
return(new ObservableQuery <Continuation <T[]>, TFilter>(
(f, p) => storeObs
.StartWith <T[]>(store())
.Select(allRecords =>
{
var currentTokenMeta = PagingToken.FromToken(p.Token, p.Size);
var pagedView = allRecords;
try
{
if (f != null) //apply filter if specified
{
pagedView = allRecords.Where(r => filerFunc(f, r)).ToArray();
}
if (p.Size.HasValue) //apply record limiter / pager if specified
{
var offset = currentTokenMeta.Index.HasValue ? currentTokenMeta.Index.Value - 1 : 0;
pagedView = pagedView.Skip(offset * p.Size.Value).Take(p.Size.Value).ToArray();
}
}
catch (Exception e)
{
Debug.WriteLine("QueryableStore Size or Filter function failure: {0}", e);
}
var total = pagedView.Length == 0 ? 0 : allRecords.Length + 1;
var nextPageToken = currentTokenMeta.Next(pagedView.Length, total);
var nextToken = p.Next(nextPageToken.ToString(), total, nextPageToken.HasMorePages());
return new Continuation <T[]>(pagedView, nextToken);
}).Where(w => w.Records.Length > 0),
filterStream,
token,
scheduler
));
}
public static IObservable <T[]> CreateQueryableStore1 <T, TFilter, TEvent>(this IObservable <TEvent> stream, Func <TFilter, ContinuationToken, IObservable <Continuation <T[]> > > queryFunc, Func <T[]> store, ISubject <TFilter> filterStream, Func <TFilter, T, bool> filerFunc, ContinuationToken token, Func <TEvent, bool> updateWhen, IScheduler scheduler = null)
{
Func <TFilter, ContinuationToken, IObservable <T[]> > localQueryFunc =
(f, p) => store()
.ToObservable()
.Select(allRecords =>
{
var currentTokenMeta = PagingToken.FromToken(p.Token, p.Size);
var pagedView = allRecords;
try
{
if (f != null) //apply filter if specified
{
pagedView = allRecords.Where(r => filerFunc(f, r)).ToArray();
}
if (p.Size.HasValue) //apply record limiter / pager if specified
{
var offset = currentTokenMeta.Index.HasValue ? currentTokenMeta.Index.Value - 1 : 0;
pagedView = pagedView.Skip(offset * p.Size.Value).Take(p.Size.Value).ToArray();
}
}
catch (Exception e)
{
Debug.WriteLine("QueryableStore Size or Filter function failure: {0}", e);
}
var total = pagedView.Length == 0 ? 0 : allRecords.Length + 1;
var nextPageToken = currentTokenMeta.Next(pagedView.Length, total);
var nextToken = p.Next(nextPageToken.ToString(), total, nextPageToken.HasMorePages());
return(new Continuation <T[]>(pagedView, nextToken));
}).Where(w => w.Records.Length > 0).Select(_ => _.Records);
var storeMutationEvents = stream.Where(updateWhen);
var view = CreateViewFromQuery(filterStream, token, queryFunc, scheduler);
var viewPipeline = view.Select(_ => _.Records).CombineLatest(storeMutationEvents, (a, b) => localQueryFunc(view.Filter.Value(), view.Continuation.Value())).SelectMany(q => q);
return(viewPipeline);
}
