/// <summary>
/// Populate this collection with another collection of items
/// </summary>
/// <param name="items">The items to populate this collection with</param>
private void InternalLoadCollection(IEnumerable <T> items)
{
Debug.Assert(items != null, "items != null");
// For SDP, we must execute the Query implicitly
DataServiceQuery <T> query = items as DataServiceQuery <T>;
if (query != null)
{
items = query.Execute() as QueryOperationResponse <T>;
}
foreach (T item in items)
{
// if this is too slow, consider hashing the set
// or just use LoadProperties
if (!this.Contains(item))
{
this.Add(item);
}
}
QueryOperationResponse <T> response = items as QueryOperationResponse <T>;
if (response != null)
{
// this should never be throwing (since we've enumerated already)!
// Note: Inner collection's nextPartLinkUri is set by the materializer
this.continuation = response.GetContinuation();
}
else
{
this.continuation = null;
}
}
/// <summary>Set the continuation for the following results for a collection.</summary>
/// <param name="collection">The collection to set the links to</param>
/// <param name="continuation">The continuation for the collection.</param>
internal static void SetNextLinkForCollection(object collection, DataServiceQueryContinuation continuation)
{
Debug.Assert(collection != null, "collection != null");
// We do a convention call for setting Continuation. We'll invoke this
// for all properties named 'Continuation' that is a DataServiceQueryContinuation
// (assigning to a single one would make it inconsistent if reflection
// order is changed).
foreach (var property in collection.GetType().GetPublicProperties(true /*instanceOnly*/))
{
if (property.Name != "Continuation" || !property.CanWrite)
{
continue;
}
if (typeof(DataServiceQueryContinuation).IsAssignableFrom(property.PropertyType))
{
property.SetValue(collection, continuation, null);
}
}
}
/// <summary>
/// Returns the next link URI for the collection key
/// </summary>
/// <param name="key">The collection for which the Uri is returned, or null, if the top level link is to be returned</param>
/// <returns>An Uri pointing to the next page for the collection</returns>
internal virtual DataServiceQueryContinuation GetContinuation(IEnumerable key)
{
Debug.Assert(this.materializer != null, "Materializer is null!");
DataServiceQueryContinuation result;
if (key == null)
{
if ((this.expectingPrimitiveValue && !this.moved) || (!this.expectingPrimitiveValue && !this.materializer.IsEndOfStream))
{
// expectingSingleValue && !moved : haven't started parsing single value (single value should not have next link anyway)
// !expectingSingleValue && !IsEndOfStream : collection type feed did not finish parsing yet
throw new InvalidOperationException(Strings.MaterializeFromAtom_TopLevelLinkNotAvailable);
}
// we have already moved to the end of stream
// are we singleton or just an entry?
if (this.expectingPrimitiveValue || this.materializer.CurrentFeed == null)
{
result = null;
}
else
{
// DEVNOTE(pqian): The next link uri should never be edited by the client, and therefore it must be absolute
result = DataServiceQueryContinuation.Create(
this.materializer.CurrentFeed.NextPageLink,
this.materializer.MaterializeEntryPlan);
}
}
else
{
if (!this.materializer.NextLinkTable.TryGetValue(key, out result))
{
// someone has asked for a collection that's "out of scope" or doesn't exist
throw new ArgumentException(Strings.MaterializeFromAtom_CollectionKeyNotPresentInLinkTable);
}
}
return(result);
}
/// <summary>
/// Populate this collection with another collection of items
/// </summary>
/// <param name="items">The items to populate this collection with</param>
private void InternalLoadCollection(IEnumerable <T> items)
{
Debug.Assert(items != null, "items != null");
#if !ASTORIA_LIGHT && !PORTABLELIB
// For SDP, we must execute the Query implicitly
DataServiceQuery <T> query = items as DataServiceQuery <T>;
if (query != null)
{
items = query.Execute() as QueryOperationResponse <T>;
}
#else
Debug.Assert(!(items is DataServiceQuery), "SL Client using DSQ as items...should have been caught by ValidateIteratorParameter.");
#endif
foreach (T item in items)
{
// if this is too slow, consider hashing the set
// or just use LoadProperties
if (!this.Contains(item))
{
this.Add(item);
}
}
QueryOperationResponse <T> response = items as QueryOperationResponse <T>;
if (response != null)
{
// this should never be throwing (since we've enumerated already)!
// Note: Inner collection's nextPartLinkUri is set by the materializer
this.continuation = response.GetContinuation();
}
else
{
this.continuation = null;
}
}
private MaterializeAtom ReadPropertyFromAtom(ClientPropertyAnnotation property)
{
DataServiceContext context = (DataServiceContext)this.Source;
bool merging = context.ApplyingChanges;
try
{
context.ApplyingChanges = true;
// store the results so that they can be there in the response body.
Type elementType = property.IsEntityCollection ? property.EntityCollectionItemType : property.NullablePropertyType;
IList results = (IList)Activator.CreateInstance(typeof(List <>).MakeGenericType(elementType));
DataServiceQueryContinuation continuation = null;
// elementType.ElementType has Nullable stripped away, use nestedType for materializer
using (MaterializeAtom materializer = this.GetMaterializer(this.plan))
{
Debug.Assert(materializer != null, "materializer != null -- otherwise GetMaterializer() returned null rather than empty");
#if ASTORIA_OPEN_OBJECT
object openProperties = null;
#endif
// when SetLink to null, we cannot get materializer because have no-content response.
if (materializer.IsNoContentResponse() &&
property.GetValue(entity) != null &&
context.MergeOption != MergeOption.AppendOnly &&
context.MergeOption != MergeOption.NoTracking)
{
property.SetValue(this.entity, null, propertyName, false);
}
else
{
foreach (object child in materializer)
{
if (property.IsEntityCollection)
{
results.Add(child);
}
else if (property.IsPrimitiveOrEnumOrComplexCollection)
{
Debug.Assert(property.PropertyType.IsAssignableFrom(child.GetType()), "Created instance for storing collection items has to be compatible with the actual one.");
// Collection materialization rules requires to clear the collection if not null or set the property first and then add the collection items
object collectionInstance = property.GetValue(this.entity);
if (collectionInstance == null)
{
// type of child has been resolved as per rules for collections so it is the correct type to instantiate
collectionInstance = Activator.CreateInstance(child.GetType());
// allowAdd is false - we need to assign instance as the new property value
property.SetValue(this.entity, collectionInstance, this.propertyName, false /* allowAdd? */);
}
else
{
// Clear existing collection
property.ClearBackingICollectionInstance(collectionInstance);
}
foreach (var collectionItem in (IEnumerable)child)
{
Debug.Assert(property.PrimitiveOrComplexCollectionItemType.IsAssignableFrom(collectionItem.GetType()), "Type of materialized collection items have to be compatible with the type of collection items in the actual collection property.");
property.AddValueToBackingICollectionInstance(collectionInstance, collectionItem);
}
results.Add(collectionInstance);
}
else
{
#if ASTORIA_OPEN_OBJECT
property.SetValue(this.entity, child, this.propertyName, ref openProperties, false);
#else
// it is either primitive type, complex type or 1..1 navigation property so we just allow setting the value but not adding.
property.SetValue(this.entity, child, this.propertyName, false);
results.Add(child);
#endif
}
}
}
continuation = materializer.GetContinuation(null);
}
return(MaterializeAtom.CreateWrapper(context, results, continuation));
}
finally
{
context.ApplyingChanges = merging;
}
}
/// <summary>
/// Creates a wrapper for raw results
/// </summary>
/// <param name="context">Context of expression to analyze.</param>
/// <param name="results">the results to wrap</param>
/// <param name="continuation">The continuation for this query.</param>
internal ResultsWrapper(DataServiceContext context, IEnumerable results, DataServiceQueryContinuation continuation)
{
this.context = context;
this.results = results ?? Enumerable.Empty <object>();
this.continuation = continuation;
}
/// <summary>Creates a materializer for partial result sets.</summary>
/// <param name="context">Context of expression to analyze.</param>
/// <param name="results">The current page of results</param>
/// <param name="continuation">The continuation for the results.</param>
/// <returns>A new materializer.</returns>
internal static MaterializeAtom CreateWrapper(DataServiceContext context, IEnumerable results, DataServiceQueryContinuation continuation)
{
return(new ResultsWrapper(context, results, continuation));
}
