/// <summary>
/// Creates a new metadata cache using the specified external and local metadata services.
/// </summary>
/// <param name="external">External metadata service to fall back to for lookups.</param>
/// <param name="local">Local metadata service used for caching of immutable resources that can be shared safely across users of the metadata service.</param>
public ReactiveMetadataCache(IReactiveMetadata external, IReactiveMetadataInMemory local)
{
_observables = new LeveledCacheQueryableDictionary <IReactiveObservableDefinition>(external.Observables, local.Observables);
_observers = new LeveledCacheQueryableDictionary <IReactiveObserverDefinition>(external.Observers, local.Observers);
_streamFactories = new LeveledCacheQueryableDictionary <IReactiveStreamFactoryDefinition>(external.StreamFactories, local.StreamFactories);
_subscriptionFactories = new LeveledCacheQueryableDictionary <IReactiveSubscriptionFactoryDefinition>(external.SubscriptionFactories, local.SubscriptionFactories);
_subscriptions = new LeveledCacheQueryableDictionary <IReactiveSubscriptionProcess>(external.Subscriptions, local.Subscriptions);
_streams = new LeveledCacheQueryableDictionary <IReactiveStreamProcess>(external.Streams, local.Streams);
}
/// <summary>
/// Creates a new query engine that's aware of host services.
/// </summary>
/// <param name="uri">URI identifying the query engine.</param>
/// <param name="serviceResolver">Resolver used by the query engine to
/// resolve artifacts to reactive services for delegation of requests or
/// other operations.</param>
/// <param name="scheduler">Scheduler used by the query engine to
/// schedule work, also allowing for pausing during checkpointing
/// operations.</param>
/// <param name="metadataRegistry">Metadata consulted by the query
/// engine to lookup artifact definitions.</param>
/// <param name="traceSource">Tracer to log to.</param>
public QueryEvaluatorQueryEngine(
Uri uri,
IReactiveServiceResolver serviceResolver,
IScheduler scheduler,
IReactiveMetadata metadataRegistry,
IKeyValueStore keyValueStore,
TraceSource traceSource,
IReadOnlyDictionary <string, object> context)
: base(uri, serviceResolver, scheduler, metadataRegistry, keyValueStore, SerializationPolicy.Default, s_map, traceSource)
{
_context = context;
_traceSource = traceSource;
}
public bool TryLookupSubscriptionFactory(IReactiveMetadata metadata, string key, out SubscriptionFactoryDefinitionEntity entity)
{
if (metadata.SubscriptionFactories.TryGetValue(new Uri(key), out IReactiveSubscriptionFactoryDefinition subscriptionFactoryDefinition))
{
var expression = _metadataRewrites.GetValue(
subscriptionFactoryDefinition.Expression,
e => _queryEngine.RewriteQuotedReactiveToSubscribable(e));
entity = new SubscriptionFactoryDefinitionEntity(subscriptionFactoryDefinition.Uri, expression, subscriptionFactoryDefinition.State);
return(true);
}
entity = null;
return(false);
}
private bool TryCreateStreamFromMetadata(IReactiveMetadata metadata, string key, out SubjectEntity subject)
{
//
// Lookup the stream definition from metadata. If we find a
// remote definition, a singleton instance should be created.
// Note, in a proper architecture, the stream would have
// already been created (via invocation of a stream factory or
// otherwise) before we reached this point in subscription
// creation. Thus, we would have found a stream instance in the
// local registry, and this code would not be executed.
//
if (metadata.Streams.TryGetValue(new Uri(key), out IReactiveStreamProcess streamProcess))
{
lock (_createStreamGate)
{
// TODO: rewrite stream expression based on bound type of stream factory
if (!_queryEngine._registry.Subjects.TryGetValue(key, out subject))
{
var streamExpr = RewriteQuotedReactiveStreamToUntyped(key, streamProcess.Expression);
Expression expr = _queryEngine.RewriteQuotedReactiveToSubscribable(streamExpr);
_queryEngine._engine.CreateStream(new Uri(key), expr, null);
_queryEngine.TraceSource.LazyStream_Created(key, _queryEngine.Uri, expr.ToTraceString());
if (_queryEngine._registry.Subjects.TryGetValue(key, out subject))
{
subject.AdvanceState(TransactionState.Active);
}
else
{
throw new InvalidOperationException(
string.Format(CultureInfo.InvariantCulture, "Attempt to lazily create stream '{0}' on query engine '{1}' has failed.", key, _queryEngine.Uri.ToCanonicalString()));
}
}
}
return(true);
}
subject = null;
return(false);
}
public bool TryLookupObservable(IReactiveMetadata metadata, string key, out ObservableDefinitionEntity entity)
{
if (metadata.Observables.TryGetValue(new Uri(key), out IReactiveObservableDefinition observableDefinition))
{
var expression = _metadataRewrites.GetValue(
observableDefinition.Expression,
e => _queryEngine.RewriteQuotedReactiveToSubscribable(e));
entity = new ObservableDefinitionEntity(observableDefinition.Uri, expression, observableDefinition.State);
return(true);
}
// Will result in a stream being created if a definition exists
// in the remote metadata store. This path should only succeed
// when hit by the definition inlining binder.
if (TryCreateStreamFromMetadata(metadata, key, out var subject))
{
entity = ObservableDefinitionEntity.FromSubject(subject);
return(true);
}
entity = null;
return(false);
}
public BuiltinEntitiesRegistry(CheckpointingQueryEngine queryEngine, IReactiveMetadata metadata)
{
Debug.Assert(queryEngine != null);
Debug.Assert(metadata != null);
_queryEngine = queryEngine;
_subjects = new ReactiveEntityCollection <string, SubjectEntity>(StringComparer.Ordinal);
var localObservables = new ReactiveEntityCollection <string, ObservableDefinitionEntity>(StringComparer.Ordinal);
var localObservablesAndSubjects = new ChainedLookupReactiveEntityCollection <string, ObservableDefinitionEntity, SubjectEntity>(localObservables, _subjects, s => ObservableDefinitionEntity.FromSubject(s));
_observables = new ExternalLookupReactiveEntityCollection <ObservableDefinitionEntity>(localObservablesAndSubjects, TryLookupObservable, metadata);
var localObservers = new ReactiveEntityCollection <string, ObserverDefinitionEntity>(StringComparer.Ordinal);
var localObserversAndSubjects = new ChainedLookupReactiveEntityCollection <string, ObserverDefinitionEntity, SubjectEntity>(localObservers, _subjects, s => ObserverDefinitionEntity.FromSubject(s));
_observers = new ExternalLookupReactiveEntityCollection <ObserverDefinitionEntity>(localObserversAndSubjects, TryLookupObserver, metadata);
var localSubjectFactories = new ReactiveEntityCollection <string, StreamFactoryDefinitionEntity>(StringComparer.Ordinal);
_subjectFactories = new ExternalLookupReactiveEntityCollection <StreamFactoryDefinitionEntity>(localSubjectFactories, TryLookupStreamFactory, metadata);
var localSubscriptionFactories = new ReactiveEntityCollection <string, SubscriptionFactoryDefinitionEntity>(StringComparer.Ordinal);
_subscriptionFactories = new ExternalLookupReactiveEntityCollection <SubscriptionFactoryDefinitionEntity>(localSubscriptionFactories, TryLookupSubscriptionFactory, metadata);
_other = new ReactiveEntityCollection <string, DefinitionEntity>(StringComparer.Ordinal);
_templates = new InvertedLookupReactiveEntityCollection <string, DefinitionEntity>(StringComparer.Ordinal, InvertedDefinitionEntityComparer.Default);
_subscriptions = new ReactiveEntityCollection <string, SubscriptionEntity>(StringComparer.Ordinal);
_reliableSubscriptions = new ReactiveEntityCollection <string, ReliableSubscriptionEntity>(StringComparer.Ordinal);
_metadataRewrites = new ConditionalWeakTable <Expression, Expression>();
InitializeBuiltinDefinitions(queryEngine);
}
protected override CheckpointingQueryEngine CreateQueryEngine(System.Uri uri, IReactiveServiceResolver resolver, IScheduler scheduler, IReactiveMetadata metadata, IKeyValueStore keyValueStore, TraceSource traceSource, IReadOnlyDictionary <string, object> contextElements)
{
var engine = base.CreateQueryEngine(uri, resolver, scheduler, metadata, keyValueStore, traceSource, contextElements);
#pragma warning disable IDE0034 // Simplify 'default' expression (illustrative of method signature)
#pragma warning disable CA1305 // Specify IFormatProvider (captured in expression tree)
var constantHoister = ConstantHoister.Create(
true,
(Expression <Func <string, string> >)(c => string.Format(c, default(object))),
(Expression <Func <string, string> >)(c => string.Format(c, default(object), default(object))),
(Expression <Func <string, string> >)(c => string.Format(c, default(object), default(object), default(object))),
(Expression <Func <string, string> >)(c => string.Format(c, default(object[]))),
(Expression <Func <string, string> >)(c => string.Format(default(IFormatProvider), c, default(object[]))),
(Expression <Func <string, JProperty> >)(c => new JProperty(c, default(object))),
(Expression <Func <string, JProperty> >)(c => new JProperty(c, default(object[]))));
#pragma warning restore CA1305 // Specify IFormatProvider
#pragma warning restore IDE0034 // Simplify 'default' expression
engine.Options.ExpressionPolicy.DelegateCache = new SimpleCompiledDelegateCache();
engine.Options.ExpressionPolicy.InMemoryCache = new QueryEvaluatorExpressionHeap(constantHoister);
engine.Options.ExpressionPolicy.ConstantHoister = constantHoister;
return(engine);
}
public ExternalLookupReactiveEntityCollection(IReactiveEntityCollection <string, TDefinitionEntity> local, TryLookup <IReactiveMetadata, string, TDefinitionEntity> lookupFunc, IReactiveMetadata external)
: base(local, lookupFunc, external)
{
}
/// <summary>
/// Looks up the free variable name in the Reactive metadata and attempts to unify entity types.
/// </summary>
/// <param name="free">The free variable.</param>
/// <param name="metadata">The metadata to unify aginst.</param>
/// <returns>
/// Unifications between the free variable type and the known resource type.
/// </returns>
internal static IEnumerable <KeyValuePair <TypeSlim, Type> > FindAndUnify(ParameterExpressionSlim free, IReactiveMetadata metadata)
{
var reactiveType = ReactiveEntityTypeExtensions.FromTypeSlim(free.Type);
if ((reactiveType & ReactiveEntityType.Func) == ReactiveEntityType.Func)
{
reactiveType ^= ReactiveEntityType.Func;
}
var metadataType = default(Type);
switch (reactiveType)
{
case ReactiveEntityType.Observer:
if (metadata.Observers.TryGetValue(new Uri(free.Name), out var observer))
{
metadataType = observer.Expression.Type;
}
break;
case ReactiveEntityType.Observable:
if (metadata.Observables.TryGetValue(new Uri(free.Name), out var observable))
{
metadataType = observable.Expression.Type;
}
break;
case ReactiveEntityType.SubscriptionFactory:
if (metadata.SubscriptionFactories.TryGetValue(new Uri(free.Name), out var subscriptionFactory))
{
metadataType = subscriptionFactory.Expression.Type;
}
break;
case ReactiveEntityType.Subscription:
if (metadata.Subscriptions.TryGetValue(new Uri(free.Name), out var subscription))
{
metadataType = subscription.Expression.Type;
}
break;
case ReactiveEntityType.StreamFactory:
if (metadata.StreamFactories.TryGetValue(new Uri(free.Name), out var streamFactory))
{
metadataType = streamFactory.Expression.Type;
}
break;
case ReactiveEntityType.Stream:
if (metadata.Streams.TryGetValue(new Uri(free.Name), out var stream))
{
metadataType = stream.Expression.Type;
}
break;
}
if (metadataType != null)
{
var unifier = new DataModelTypeUnifier();
if (unifier.Unify(metadataType, free.Type))
{
return(unifier.Entries);
}
}
return(Array.Empty <KeyValuePair <TypeSlim, Type> >());
}
/// <summary>
/// Initializes a new instance of the <see cref="UnifyingSerializationHelpers"/>
/// class to serialize and deserialize expressions and data model-compliant objects.
/// </summary>
/// <param name="metadata">
/// The source of unbound parameter definitions for unification.
/// </param>
public UnifyingSerializationHelpers(IReactiveMetadata metadata)
{
_metadata = metadata;
}
public CheckpointingQueryEngine(Uri uri, IReactiveServiceResolver serviceResolver, IScheduler scheduler, IReactiveMetadata metadataRegistry, IKeyValueStore keyValueStore, IQuotedTypeConversionTargets quotedTypeConversionTargets, TraceSource traceSource, ICompiledDelegateCache delegateCache)
: base(uri, serviceResolver, scheduler, metadataRegistry, keyValueStore, SerializationPolicy.Default, quotedTypeConversionTargets, traceSource, delegateCache)
{
_objectSpace = new PersistedObjectSpace(new SerializationFactory());
}