public StrongReferenceContainer Prefetch(Key key, TypeInfo type, IList <PrefetchFieldDescriptor> descriptors)
{
ArgumentValidator.EnsureArgumentNotNull(key, "key");
ArgumentValidator.EnsureArgumentNotNull(descriptors, "fields");
if (descriptors.Count == 0)
{
return(null);
}
try {
EnsureKeyTypeCorrespondsToSpecifiedType(key, type);
EntityState ownerState;
var currentKey = key;
if (!TryGetTupleOfNonRemovedEntity(ref currentKey, out ownerState))
{
return(null);
}
var selectedFields = descriptors;
var currentType = type;
StrongReferenceContainer hierarchyRootContainer = null;
var isKeyTypeExact = currentKey.HasExactType ||
currentKey.TypeReference.Type.IsLeaf ||
currentKey.TypeReference.Type == type;
if (isKeyTypeExact)
{
currentType = currentKey.TypeReference.Type;
EnsureAllFieldsBelongToSpecifiedType(descriptors, currentType);
}
else
{
ArgumentValidator.EnsureArgumentNotNull(currentType, "type");
EnsureAllFieldsBelongToSpecifiedType(descriptors, currentType);
SetUpContainers(currentKey, currentKey.TypeReference.Type,
PrefetchHelper.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, currentKey.TypeReference.Type),
true, ownerState, true);
var hierarchyRoot = currentKey.TypeReference.Type;
selectedFields = descriptors
.Where(descriptor => descriptor.Field.DeclaringType != hierarchyRoot)
.ToList();
}
SetUpContainers(currentKey, currentType, selectedFields, isKeyTypeExact, ownerState, ReferenceEquals(descriptors, selectedFields));
StrongReferenceContainer container = null;
if (graphContainers.Count >= MaxContainerCount)
{
container = ExecuteTasks();
}
if (referenceContainer != null)
{
referenceContainer.JoinIfPossible(container);
return(referenceContainer);
}
return(container);
}
catch {
CancelTasks();
throw;
}
}
/// <summary>
/// Joins this instance with <paramref name="other"/>.
/// </summary>
/// <param name="other">The other container.</param>
public bool Join(StrongReferenceContainer other)
{
if (other == null)
{
return(false);
}
if (!IsRoot)
{
root.Join(other);
return(true);
}
if (!other.IsRoot)
{
throw new InvalidOperationException();
}
other.root = this;
if (lastJoinedContainer == null)
{
nextJoinedContainer = other;
}
else if (lastJoinedContainer.nextJoinedContainer != null)
{
throw new InvalidOperationException();
}
else
{
lastJoinedContainer.nextJoinedContainer = other;
}
lastJoinedContainer = other.lastJoinedContainer ?? other;
return(true);
}
public void SaveStrongReference(EntityState reference)
{
if (referenceContainer == null)
{
referenceContainer = new StrongReferenceContainer(null);
}
_ = referenceContainer.Join(new StrongReferenceContainer(reference));
}
public IEnumerator <T> GetEnumerator()
{
TypeInfo modelType;
session.Domain.Model.Types.TryGetValue(typeof(T), out modelType);
var taskCount = session.Handler.PrefetchTaskExecutionCount;
var container = new StrongReferenceContainer(null);
var fieldDescriptors = new List <PrefetchFieldDescriptor>();
var resultQueue = new Queue <Key>();
var unknownTypeQueue = new Queue <Key>();
var se = source.GetEnumerator();
bool exists;
do
{
exists = se.MoveNext();
if (exists)
{
var key = se.Current;
var type = key.HasExactType || modelType == null
? key.TypeReference.Type
: modelType;
if (!key.HasExactType && !type.IsLeaf)
{
unknownTypeQueue.Enqueue(key);
}
resultQueue.Enqueue(key);
var defaultDescriptors = PrefetchHelper.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, type);
container.JoinIfPossible(session.Handler.Prefetch(key, type, defaultDescriptors));
}
if (exists && taskCount == session.Handler.PrefetchTaskExecutionCount)
{
continue;
}
if (!exists)
{
container.JoinIfPossible(session.Handler.ExecutePrefetchTasks());
}
if (unknownTypeQueue.Count > 0)
{
while (unknownTypeQueue.Count > 0)
{
var unknownKey = unknownTypeQueue.Dequeue();
var unknownType = session.EntityStateCache[unknownKey, false].Type;
var unknownDescriptors = PrefetchHelper.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, unknownType);
session.Handler.Prefetch(unknownKey, unknownType, unknownDescriptors);
}
session.Handler.ExecutePrefetchTasks();
}
while (resultQueue.Count > 0)
{
yield return((T)(IEntity)session.EntityStateCache[resultQueue.Dequeue(), true].Entity);
}
taskCount = session.Handler.PrefetchTaskExecutionCount;
} while (exists);
}
/// <summary>
/// Joins this instance with <paramref name="other"/>,
/// if <paramref name="other"/> is not <see langword="null" /> and is the root of other containers' chain.
/// </summary>
/// <param name="other">The other container.</param>
public bool JoinIfPossible(StrongReferenceContainer other)
{
if (other == null)
{
return(false);
}
if (other.IsRoot)
{
Join(other);
}
return(true);
}
public IEnumerator <TItem> GetEnumerator()
{
var currentTaskCount = sessionHandler.PrefetchTaskExecutionCount;
var aggregatedNodes = NodeAggregator <TItem> .Aggregate(nodes);
var resultQueue = new Queue <TItem>();
var container = new StrongReferenceContainer(null);
foreach (var item in source)
{
resultQueue.Enqueue(item);
if (item != null)
{
foreach (var extractorNode in aggregatedNodes)
{
container.JoinIfPossible(RegisterPrefetch(extractorNode.ExtractKeys(item), extractorNode));
}
}
if (currentTaskCount == sessionHandler.PrefetchTaskExecutionCount)
{
continue;
}
while (container.JoinIfPossible(sessionHandler.ExecutePrefetchTasks()))
{
container.JoinIfPossible(ProcessFetchedElements());
}
while (resultQueue.TryDequeue(out var resultItem))
{
yield return(resultItem);
}
currentTaskCount = sessionHandler.PrefetchTaskExecutionCount;
}
while (container.JoinIfPossible(sessionHandler.ExecutePrefetchTasks()))
{
container.JoinIfPossible(ProcessFetchedElements());
}
while (resultQueue.TryDequeue(out var resultItem))
{
yield return(resultItem);
}
}
private async Task <StrongReferenceContainer> RegisterPrefetchAsync(IReadOnlyCollection <Key> keys,
IHasNestedNodes fieldContainer, Guid enumerationId, CancellationToken token)
{
var container = new StrongReferenceContainer(null);
TypeInfo modelType = null;
if (fieldContainer is ReferenceNode refNode)
{
modelType = refNode.ReferenceType;
}
foreach (var key in keys)
{
var type = key.HasExactType || modelType == null
? key.TypeReference.Type
: modelType;
if (!key.HasExactType && !type.IsLeaf)
{
unknownTypeQueue.Enqueue(key);
}
var cacheKey = new Pair <IHasNestedNodes, TypeInfo>(fieldContainer, type);
if (!fieldDescriptorCache.TryGetValue(cacheKey, out var fieldDescriptors))
{
fieldDescriptors = PrefetchHelper
.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, type)
.Concat(fieldContainer.NestedNodes.Select(fn => new PrefetchFieldDescriptor(fn.Field, false, true, enumerationId)))
.ToList();
fieldDescriptorCache.Add(cacheKey, fieldDescriptors);
}
_ = container.JoinIfPossible(
await sessionHandler.PrefetchAsync(key, type, fieldDescriptors, token).ConfigureAwait(false));
}
var nestedContainers = fieldContainer.NestedNodes.OfType <IHasNestedNodes>();
foreach (var nestedContainer in nestedContainers)
{
prefetchQueue.Enqueue(new Pair <IEnumerable <Key>, IHasNestedNodes>(keys, nestedContainer));
}
return(container);
}
public StrongReferenceContainer ExecuteTasks(bool skipPersist)
{
if (graphContainers.Count == 0)
{
referenceContainer = null;
return(null);
}
try {
var batchExecuted = fetcher.ExecuteTasks(graphContainers, skipPersist);
TaskExecutionCount += batchExecuted;
foreach (var graphContainer in graphContainers)
{
graphContainer.NotifyAboutExtractionOfKeysWithUnknownType();
}
return(referenceContainer);
}
finally {
CancelTasks();
}
}
private async ValueTask <StrongReferenceContainer> ExecuteTasks(bool skipPersist, bool isAsync, CancellationToken token)
{
if (graphContainers.Count == 0)
{
referenceContainer = null;
return(null);
}
try {
var batchExecuted =
await fetcher.ExecuteTasks(graphContainers, skipPersist, isAsync, token).ConfigureAwait(false);
TaskExecutionCount += batchExecuted;
foreach (var graphContainer in graphContainers)
{
graphContainer.NotifyAboutExtractionOfKeysWithUnknownType();
}
return(referenceContainer);
}
finally {
CancelTasks();
}
}
private StrongReferenceContainer RegisterPrefetch(IEnumerable <Key> keys, IHasNestedNodes fieldContainer)
{
var container = new StrongReferenceContainer(null);
TypeInfo modelType = null;
var refNode = fieldContainer as ReferenceNode;
if (refNode != null)
{
modelType = refNode.ReferenceType;
}
foreach (var key in keys)
{
var type = key.HasExactType || modelType == null
? key.TypeReference.Type
: modelType;
if (!key.HasExactType && !type.IsLeaf)
{
unknownTypeQueue.Enqueue(key);
}
IList <PrefetchFieldDescriptor> fieldDescriptors;
var cacheKey = new Pair <IHasNestedNodes, TypeInfo>(fieldContainer, type);
if (!fieldDescriptorCache.TryGetValue(cacheKey, out fieldDescriptors))
{
fieldDescriptors = PrefetchHelper
.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, type)
.Concat(fieldContainer.NestedNodes.Select(fn => new PrefetchFieldDescriptor(fn.Field, false, true))).ToList();
fieldDescriptorCache.Add(cacheKey, fieldDescriptors);
}
container.JoinIfPossible(sessionHandler.Prefetch(key, type, fieldDescriptors));
}
var nestedContainers = fieldContainer.NestedNodes.OfType <IHasNestedNodes>();
foreach (var nestedContainer in nestedContainers)
{
prefetchQueue.Enqueue(new Pair <IEnumerable <Key>, IHasNestedNodes>(keys, nestedContainer));
}
return(container);
}
private async Task <StrongReferenceContainer> ProcessFetchedElementsAsync(Guid enumerationId, CancellationToken token)
{
var container = new StrongReferenceContainer(null);
while (unknownTypeQueue.TryDequeue(out var unknownKey))
{
var unknownType = session.EntityStateCache[unknownKey, false].Type;
var unknownDescriptors =
PrefetchHelper.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, unknownType);
_ = await sessionHandler.PrefetchAsync(unknownKey, unknownType, unknownDescriptors, token).ConfigureAwait(false);
}
while (prefetchQueue.TryDequeue(out var pair))
{
var parentKeys = pair.First;
var nestedNodes = pair.Second;
var keys = new List <Key>();
foreach (var parentKey in parentKeys)
{
var entityState = session.EntityStateCache[parentKey, false];
if (entityState == null)
{
_ = container.JoinIfPossible(await sessionHandler.ExecutePrefetchTasksAsync(true, token).ConfigureAwait(false));
entityState = session.EntityStateCache[parentKey, false];
if (entityState == null)
{
throw new InvalidOperationException(string.Format(Strings.ExCannotResolveEntityWithKeyX, parentKey));
}
}
keys.AddRange(nestedNodes.ExtractKeys(entityState.Entity));
}
_ = container.JoinIfPossible(await RegisterPrefetchAsync(keys, nestedNodes, enumerationId, token).ConfigureAwait(false));
}
return(container);
}
private StrongReferenceContainer ProcessFetchedElements()
{
var container = new StrongReferenceContainer(null);
taskCount = sessionHandler.PrefetchTaskExecutionCount;
while (unknownTypeQueue.Count > 0)
{
var unknownKey = unknownTypeQueue.Dequeue();
var unknownType = session.EntityStateCache[unknownKey, false].Type;
var unknownDescriptors = PrefetchHelper.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, unknownType);
sessionHandler.Prefetch(unknownKey, unknownType, unknownDescriptors);
}
while (prefetchQueue.Count > 0)
{
var pair = prefetchQueue.Dequeue();
var parentKeys = pair.First;
var nestedNodes = pair.Second;
var keys = new List <Key>();
foreach (var parentKey in parentKeys)
{
var entityState = session.EntityStateCache[parentKey, false];
if (entityState == null)
{
container.JoinIfPossible(sessionHandler.ExecutePrefetchTasks(true));
taskCount = sessionHandler.PrefetchTaskExecutionCount;
entityState = session.EntityStateCache[parentKey, false];
if (entityState == null)
{
throw new InvalidOperationException(string.Format(Strings.ExCannotResolveEntityWithKeyX, parentKey));
}
}
keys.AddRange(nestedNodes.ExtractKeys(entityState.Entity));
}
container.JoinIfPossible(RegisterPrefetch(keys, nestedNodes));
}
return(container);
}
public async IAsyncEnumerator <TItem> GetAsyncEnumerator(CancellationToken token = default)
{
var currentTaskCount = sessionHandler.PrefetchTaskExecutionCount;
var aggregatedNodes = NodeAggregator <TItem> .Aggregate(nodes);
var resultQueue = new Queue <TItem>();
strongReferenceContainer = new StrongReferenceContainer(null);
var enumerationIdentifier = Guid.NewGuid();
async IAsyncEnumerable <TItem> ProcessItem(TItem item1)
{
resultQueue.Enqueue(item1);
if (item1 != null)
{
foreach (var extractorNode in aggregatedNodes)
{
var fetchedItems =
await RegisterPrefetchAsync(extractorNode.ExtractKeys(item1), extractorNode, enumerationIdentifier, token).ConfigureAwait(false);
_ = strongReferenceContainer.JoinIfPossible(fetchedItems);
}
}
if (currentTaskCount == sessionHandler.PrefetchTaskExecutionCount)
{
yield break;
}
while (strongReferenceContainer.JoinIfPossible(
await sessionHandler.ExecutePrefetchTasksAsync(token).ConfigureAwait(false)))
{
_ = strongReferenceContainer.JoinIfPossible(await ProcessFetchedElementsAsync(enumerationIdentifier, token).ConfigureAwait(false));
}
while (resultQueue.TryDequeue(out var resultItem))
{
yield return(resultItem);
}
currentTaskCount = sessionHandler.PrefetchTaskExecutionCount;
}
if (source is IAsyncEnumerable <TItem> asyncItemSource)
{
await foreach (var item in asyncItemSource.WithCancellation(token).ConfigureAwait(false))
{
await foreach (var p in ProcessItem(item).WithCancellation(token).ConfigureAwait(false))
{
yield return(p);
}
}
}
else
{
var items = source is IQueryable <TItem> queryableSource
? await queryableSource.ExecuteAsync(token).ConfigureAwait(false)
: source;
foreach (var item in items)
{
await foreach (var p in ProcessItem(item).WithCancellation(token).ConfigureAwait(false))
{
yield return(p);
}
}
}
while (strongReferenceContainer.JoinIfPossible(
await sessionHandler.ExecutePrefetchTasksAsync(token).ConfigureAwait(false)))
{
_ = strongReferenceContainer.JoinIfPossible(await ProcessFetchedElementsAsync(enumerationIdentifier, token).ConfigureAwait(false));
}
while (resultQueue.TryDequeue(out var resultItem))
{
yield return(resultItem);
}
}
public void CancelTasks()
{
referenceContainer = null;
graphContainers.Clear();
}
public async IAsyncEnumerator <T> GetAsyncEnumerator(CancellationToken token = default)
{
session.Domain.Model.Types.TryGetValue(typeof(T), out var modelType);
var taskCount = session.Handler.PrefetchTaskExecutionCount;
var container = new StrongReferenceContainer(null);
var resultQueue = new Queue <Key>();
var unknownTypeQueue = new Queue <Key>();
using var se = source.GetEnumerator();
bool exists;
do
{
exists = se.MoveNext();
if (exists)
{
var key = se.Current;
var type = key.HasExactType || modelType == null
? key.TypeReference.Type
: modelType;
if (!key.HasExactType && !type.IsLeaf)
{
unknownTypeQueue.Enqueue(key);
}
resultQueue.Enqueue(key);
var defaultDescriptors = PrefetchHelper.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, type);
container.JoinIfPossible(
await session.Handler.PrefetchAsync(key, type, defaultDescriptors, token).ConfigureAwait(false));
}
if (exists && taskCount == session.Handler.PrefetchTaskExecutionCount)
{
continue;
}
if (!exists)
{
container.JoinIfPossible(
await session.Handler.ExecutePrefetchTasksAsync(token).ConfigureAwait(false));
}
if (unknownTypeQueue.Count > 0)
{
while (unknownTypeQueue.Count > 0)
{
var unknownKey = unknownTypeQueue.Dequeue();
var unknownType = session.EntityStateCache[unknownKey, false].Type;
var unknownDescriptors =
PrefetchHelper.GetCachedDescriptorsForFieldsLoadedByDefault(session.Domain, unknownType);
await session.Handler.PrefetchAsync(
unknownKey, unknownType, unknownDescriptors, token).ConfigureAwait(false);
}
await session.Handler.ExecutePrefetchTasksAsync(token).ConfigureAwait(false);
}
while (resultQueue.Count > 0)
{
yield return((T)(IEntity)session.EntityStateCache[resultQueue.Dequeue(), true].Entity);
}
taskCount = session.Handler.PrefetchTaskExecutionCount;
} while (exists);
}