Class ObservableQueryEmissionGuards

Namespace: Cratis.Arc.Queries

Assembly: Cratis.Arc.Core.dll

Represents an implementation of IObservableQueryEmissionGuards.

[Singleton]
public class ObservableQueryEmissionGuards : IObservableQueryEmissionGuards

Inheritance: object

ObservableQueryEmissionGuards

Implements: IObservableQueryEmissionGuards

Inherited Members: object.GetType()

object.MemberwiseClone()

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

Extension Methods: MethodCalls.CallGenericMethod<TOut, T>(T, Expression<Func<T, Func<TOut>>>, params Type[])

MethodCalls.CallGenericMethod<TOut, T, T1>(T, Expression<Func<T, Func<T1, TOut>>>, T1, params Type[])

MethodCalls.CallGenericMethod<TOut, T, T1, T2>(T, Expression<Func<T, Func<T1, T2, TOut>>>, T1, T2, params Type[])

MethodCalls.CallGenericMethod<TOut, T, T1, T2, T3>(T, Expression<Func<T, Func<T1, T2, T3, TOut>>>, T1, T2, T3, params Type[])

ConverterExtensions.ConvertTo(object, Type)

ConceptExtensions.GetConceptValue(object)

ConceptExtensions.IsConcept(object)

JsonValueExtensions.ToJsonValue(object?)

ObservableExtensions.InvokeAndWrapWithSubject<TResult>(object, Func<CancellationToken, IObservable<TResult>>)

ObservableExtensions.InvokeAndWrapWithTransformSubject<TResult, TSource>(object, Func<CancellationToken, IObservable<TSource>>, Func<TSource, TResult>)

Remarks

The guard types are discovered once; the instances are created per emission from the per-subscription service provider carried on the ObservableQueryEmissionContext. Resolving them from the root provider instead would hand a guard whatever scoped collaborator happened to be cached there first, which for a tenant-resolving or session-reading guard is the wrong answer rather than a missing one.

Constructors

ObservableQueryEmissionGuards(ITypes, ILogger<ObservableQueryEmissionGuards>)

Initializes a new instance of the ObservableQueryEmissionGuards class with Arc's default serializer options.

public ObservableQueryEmissionGuards(ITypes types, ILogger<ObservableQueryEmissionGuards> logger)

Parameters

types ITypes: The types used to discover guards.
logger ILogger<ObservableQueryEmissionGuards>: The logger.

ObservableQueryEmissionGuards(ITypes, IOptions<ArcOptions>, ILogger<ObservableQueryEmissionGuards>)

Represents an implementation of IObservableQueryEmissionGuards.

public ObservableQueryEmissionGuards(ITypes types, IOptions<ArcOptions> arcOptions, ILogger<ObservableQueryEmissionGuards> logger)

Parameters

types ITypes: The ITypes used to discover IGuardObservableQueryEmission implementations.
arcOptions IOptions<ArcOptions>: The Arc options that provide the configured JSON serializer.
logger ILogger<ObservableQueryEmissionGuards>: The logger.

Remarks

Properties

HasGuards

Gets a value indicating whether any IGuardObservableQueryEmission implementation exists.

public bool HasGuards { get; }

Property Value

bool

Remarks

Emission paths check this before doing any work for a guard, so an application without guards pays nothing per emission — no context is built and no dispatch happens.

Methods

Guard(ObservableQueryEmissionContext)

Asks every discovered guard about an emission and aggregates their verdicts.

public Task<ObservableQueryEmissionVerdict> Guard(ObservableQueryEmissionContext context)

Parameters

context ObservableQueryEmissionContext: The ObservableQueryEmissionContext describing the emission.

Returns

Task<ObservableQueryEmissionVerdict>: The most restrictive ObservableQueryEmissionVerdict any guard returned.

Remarks

The aggregate is most-restrictive-wins, and the first DenyAndTerminate short-circuits the remaining guards. A guard that throws is treated as DenyAndTerminate — the failure is logged and never rethrown, because a guard that fails open would leave an application believing it is protected.