public IObservable <Either <RiakException, RiakObject> > WalkLinks(RiakObject riakObject, IList <RiakLink> riakLinks)
{
var observables = Observable.Create <Either <RiakException, RiakObject> >(async obs =>
{
try
{
System.Diagnostics.Debug.Assert(riakLinks.Count > 0, "Link walking requires at least one link");
var input = new RiakBucketKeyInput()
.Add(riakObject.Bucket, riakObject.Key);
var query = new RiakMapReduceQuery()
.Inputs(input);
var lastLink = riakLinks.Last();
foreach (var riakLink in riakLinks)
{
var link = riakLink;
var keep = ReferenceEquals(link, lastLink);
query.Link(l => l.FromRiakLink(link).Keep(keep));
}
var result = await MapReduce(query).ConfigureAwait(false);
var linkResults = result.PhaseResults
.GroupBy(r => r.Phase)
.Where(g => g.Key == riakLinks.Count - 1);
var linkResultStrings = linkResults
.SelectMany(lr => lr.ToList(), (lr, r) => new { lr, r })
.SelectMany(@t => @t.r.Values, (@t, s) => s.FromRiakString());
//var linkResultStrings = linkResults.SelectMany(g => g.Select(r => r.Values.Value.FromRiakString()));
var rawLinks = linkResultStrings
.SelectMany(RiakLink.ParseArrayFromJsonString)
.Distinct();
var oids = rawLinks
.Select(l => new RiakObjectId(l.Bucket, l.Key))
.ToList();
var source = Get(oids, new RiakGetOptions());
return(source.Subscribe(obs.OnNext,
obs.OnError,
obs.OnCompleted));
}
catch (Exception exception)
{
obs.OnError(exception);
}
return(Disposable.Empty);
});
return(observables);
}
public Task <RiakResult <IList <RiakObject> > > WalkLinks(RiakObject riakObject, IList <RiakLink> riakLinks)
{
System.Diagnostics.Debug.Assert(riakLinks.Count > 0, "Link walking requires at least one link");
var input = new RiakBucketKeyInput();
input.AddBucketKey(riakObject.Bucket, riakObject.Key);
var query = new RiakMapReduceQuery()
.Inputs(input);
var lastLink = riakLinks.Last();
foreach (var riakLink in riakLinks)
{
var link = riakLink;
var keep = ReferenceEquals(link, lastLink);
query.Link(l => l.FromRiakLink(link).Keep(keep));
}
return(MapReduce(query)
.ContinueWith((Task <RiakResult <RiakMapReduceResult> > finishedTask) => {
var result = finishedTask.Result;
if (result.IsSuccess)
{
var linkResults = result.Value.PhaseResults.GroupBy(r => r.Phase).Where(g => g.Key == riakLinks.Count - 1);
var linkResultStrings = linkResults.SelectMany(lr => lr.ToList(), (lr, r) => new { lr, r })
.SelectMany(@t => @t.r.Values, (@t, s) => s.FromRiakString());
//var linkResultStrings = linkResults.SelectMany(g => g.Select(r => r.Values.Value.FromRiakString()));
var rawLinks = linkResultStrings.SelectMany(RiakLink.ParseArrayFromJsonString).Distinct();
var oids = rawLinks.Select(l => new RiakObjectId(l.Bucket, l.Key)).ToList();
return Get(oids, new RiakGetOptions())
.ContinueWith((Task <IEnumerable <RiakResult <RiakObject> > > getTask) => {
var objects = getTask.Result;
// FIXME
// we could be discarding results here. Not good?
// This really should be a multi-phase map/reduce
return RiakResult <IList <RiakObject> > .Success(objects.Where(r => r.IsSuccess).Select(r => r.Value).ToList());
});
}
return RiakResult <IList <RiakObject> > .ErrorTask(result.ResultCode, result.ErrorMessage, result.NodeOffline);
}).Unwrap());
}
/// <summary>
/// Retrieve arbitrarily deep list of links for a <see cref="RiakObject"/>
/// </summary>
/// <returns>
/// A list of <see cref="RiakObject"/> identified by the list of links.
/// </returns>
/// <param name='riakObject'>
/// The initial object to use for the beginning of the link walking.
/// </param>
/// <param name='riakLinks'>
/// A list of link definitions
/// </param>
/// <remarks>Refer to http://wiki.basho.com/Links-and-Link-Walking.html for more information.</remarks>
public RiakResult <IList <RiakObject> > WalkLinks(RiakObject riakObject, IList <RiakLink> riakLinks)
{
var input = new RiakBucketKeyInput();
input.AddBucketKey(riakObject.Bucket, riakObject.Key);
var query = new RiakMapReduceQuery()
.Inputs(input);
foreach (var riakLink in riakLinks)
{
var link = riakLink;
var keep = link == riakLinks.Last();
query.Link(l => l.FromRiakLink(link).Keep(keep));
}
var result = MapReduce(query);
if (result.IsSuccess)
{
var linkResults = result.Value.PhaseResults.GroupBy(r => r.Phase).Where(g => g.Key == riakLinks.Count - 1);
var linkResultStrings = linkResults.SelectMany(lr => lr.ToList(), (lr, r) => new { lr, r })
.SelectMany(@t => @t.r.Values, (@t, s) => s.FromRiakString());
//var linkResultStrings = linkResults.SelectMany(g => g.Select(r => r.Values.Value.FromRiakString()));
var rawLinks = linkResultStrings.SelectMany(RiakLink.ParseArrayFromJsonString).Distinct();
var oids = rawLinks.Select(l => new RiakObjectId(l.Bucket, l.Key)).ToList();
var objects = Get(oids);
// FIXME
// we could be discarding results here. Not good?
// This really should be a multi-phase map/reduce
return(RiakResult <IList <RiakObject> > .Success(objects.Where(r => r.IsSuccess).Select(r => r.Value).ToList()));
}
return(RiakResult <IList <RiakObject> > .Error(result.ResultCode, result.ErrorMessage));
}