Class ConstraintBuilder

Namespace: Cratis.Chronicle.Events.Constraints

Assembly: Cratis.Chronicle.dll

Represents an implementation of IConstraintBuilder.

public class ConstraintBuilder : IConstraintBuilder

Inheritance: object

ConstraintBuilder

Implements: IConstraintBuilder

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>)

Constructors

ConstraintBuilder(IEventTypes, INamingPolicy, Type?)

Represents an implementation of IConstraintBuilder.

public ConstraintBuilder(IEventTypes eventTypes, INamingPolicy namingPolicy, Type? owner = null)

Parameters

eventTypes IEventTypes: Event types for the builder.
namingPolicy INamingPolicy: The INamingPolicy to use for converting names during serialization.
owner Type: Optional owner of the constraint.

Methods

AddConstraint(IConstraintDefinition)

Add a constraint to the builder.

public void AddConstraint(IConstraintDefinition constraint)

Parameters

constraint IConstraintDefinition: Constraint to add.

Build()

Build the constraint.

public IImmutableList<IConstraintDefinition> Build()

Returns

IImmutableList<IConstraintDefinition>: A collection of IConstraintDefinition to use for registering with server.

ClosesStreamOn<TEvent>(Action<IClosesStreamBuilder<TEvent>>?, ConstraintName?)

Declare an event that closes a stream scope, configured inside the callback.

public IConstraintBuilder ClosesStreamOn<TEvent>(Action<IClosesStreamBuilder<TEvent>>? configure = null, ConstraintName? name = null)

Parameters

configure Action<IClosesStreamBuilder<TEvent>>: Optional scope and reopening configuration.
name ConstraintName: Optional owner name, defaulting to the event type identifier.

Returns

IConstraintBuilder: The builder for continuation.

Type Parameters

TEvent: The closing event type.

Exceptions

ClosesStreamConstraintsNotSupported: The implementation does not support closing events.
PropertyDoesNotExistOnEventType: A closing or reopening type lacks the configured property.
MissingNameForClosesStreamConstraint: The configured owner name is reserved for manual closures.

ForEventLog()

Apply the constraints only to the event log.

public IConstraintBuilder ForEventLog()

Returns

IConstraintBuilder: Builder for continuation.

Remarks

Shorthand for ForEventSequences(params EventSequenceId[]) with Log. Uniqueness is usually a rule of the event log, and other sequences such as the outbox carry facts that were already validated there.

ForEventSequences(params EventSequenceId[])

Apply the constraints only to specific event sequences.

public IConstraintBuilder ForEventSequences(params EventSequenceId[] eventSequenceIds)

Parameters

eventSequenceIds EventSequenceId[]: The EventSequenceId values of the event sequences the constraints apply to.

Returns

IConstraintBuilder: Builder for continuation.

Remarks

By default a constraint applies to every event sequence its event types are appended to, and every sequence keeps an index of its own. The kernel neither validates nor indexes a constraint for an event sequence it does not apply to. That matters when the same event type is forwarded to another sequence, such as the outbox: the forwarded copy would otherwise claim the value in the outbox's own index, which only removal events appended to the outbox could release.

It applies to every constraint defined on this builder, wherever in the chain it is called, and calling it again adds to the event sequences already declared.

PerEventSourceType()

Scope the constraint per event source type.

public IConstraintBuilder PerEventSourceType()

Returns

IConstraintBuilder: Builder for continuation.

PerEventStreamId()

Scope the constraint per event stream identifier.

public IConstraintBuilder PerEventStreamId()

Returns

IConstraintBuilder: Builder for continuation.

PerEventStreamType()

Scope the constraint per event stream type.

public IConstraintBuilder PerEventStreamType()

Returns

IConstraintBuilder: Builder for continuation.

RemovedWith<TRemovalEventType>()

Indicate an event that releases the unique event type constraint most recently declared on this builder.

public IConstraintBuilder RemovedWith<TRemovalEventType>()

Returns

IConstraintBuilder: Builder for continuation.

Type Parameters

TRemovalEventType: Type of event that releases the constraint.

Remarks

Without this the constraint can only say "at most one, forever". Most lifecycles cycle, so declare the event that ends a cycle and the covered event types are allowed again for the next one — a covered event only violates the constraint when it comes after the most recent removal event on the same event source.

It applies to the Unique<TEventType>(ConstraintViolationMessage?, ConstraintName?) declaration it follows, which is why it belongs on the same chain. Call it as many times as the lifecycle has terminal facts: every declared event type releases the constraint on its own, and declaring a second does not replace the first. Declaring several event types under one constraint name makes them one constraint, which is released by every removal event declared for that name.

Exceptions

NoUniqueEventTypeConstraintToRemove: Thrown when no unique event type constraint has been declared on the builder yet.

Unique(Action<IUniqueConstraintBuilder>)

Start building a unique constraint.

public IConstraintBuilder Unique(Action<IUniqueConstraintBuilder> callback)

Parameters

callback Action<IUniqueConstraintBuilder>: Callback with IUniqueConstraintBuilder for building.

Returns

IConstraintBuilder: Builder for continuation.

Unique<TEventType>(ConstraintViolationMessage?, ConstraintName?)

Adds a unique constraint for a specific event type. This means there can only be one instance of this event type per event source identifier.

public IConstraintBuilder Unique<TEventType>(ConstraintViolationMessage? message = null, ConstraintName? name = null)

Parameters

message ConstraintViolationMessage: Optional message for the constraint.
name ConstraintName: Optional name for the constraint.

Returns

IConstraintBuilder: Builder for continuation.

Type Parameters

TEventType: Type of event to add for.

Unique<TEventType>(ConstraintViolationMessageProvider, ConstraintName?)

Adds a unique constraint for a specific event type. This means there can only be one instance of this event type per event source identifier.

public IConstraintBuilder Unique<TEventType>(ConstraintViolationMessageProvider messageCallback, ConstraintName? name = null)

Parameters

messageCallback ConstraintViolationMessageProvider: Callback for providing message for the constraint.
name ConstraintName: Optional name for the constraint.

Returns

IConstraintBuilder: Builder for continuation.

Type Parameters

TEventType: Type of event to add for.