Class JsonSchemaGenerator

Namespace: Cratis.Chronicle.Schemas

Assembly: Cratis.Chronicle.dll

Represents an implementation of IJsonSchemaGenerator.

[Singleton]
public class JsonSchemaGenerator : IJsonSchemaGenerator

Inheritance: object

JsonSchemaGenerator

Implements: IJsonSchemaGenerator

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

JsonSchemaGenerator(IComplianceMetadataResolver, ISecurityMetadataResolver, INamingPolicy, IDerivedTypes?)

Initializes a new instance of the JsonSchemaGenerator class.

public JsonSchemaGenerator(IComplianceMetadataResolver metadataResolver, ISecurityMetadataResolver securityMetadataResolver, INamingPolicy namingPolicy, IDerivedTypes? derivedTypes = null)

Parameters

metadataResolver IComplianceMetadataResolver: IComplianceMetadataResolver for resolving metadata.
securityMetadataResolver ISecurityMetadataResolver: ISecurityMetadataResolver for resolving security metadata - required. Security metadata is never optional: a schema that carries an [Encrypted] value is resolved through this exactly as unconditionally as a [PII] value is resolved through metadataResolver.
namingPolicy INamingPolicy: INamingPolicy to use for converting names during serialization.
derivedTypes IDerivedTypes: IDerivedTypes used to recognize polymorphic base types adorned with DerivedTypeAttribute. Defaults to the derived types of the current type universe.

JsonSchemaGenerator(IComplianceMetadataResolver, INamingPolicy, IDerivedTypes?)

Initializes a new instance of the JsonSchemaGenerator class.

public JsonSchemaGenerator(IComplianceMetadataResolver metadataResolver, INamingPolicy namingPolicy, IDerivedTypes? derivedTypes = null)

Parameters

metadataResolver IComplianceMetadataResolver: IComplianceMetadataResolver for resolving metadata.
namingPolicy INamingPolicy: INamingPolicy to use for converting names during serialization.
derivedTypes IDerivedTypes: IDerivedTypes used to recognize polymorphic base types adorned with DerivedTypeAttribute. Defaults to the derived types of the current type universe.

Remarks

Preserves the pre-[Encrypted] construction shape exactly - an instance built this way never resolves or writes security metadata, because it has no provider to resolve it from. Use the overload taking an ISecurityMetadataResolver for a generator that resolves both.

Methods

Generate(Type)

Generate a JsonSchema for a specific type.

public JsonSchema Generate(Type type)

Parameters

type Type: Type to generate for.

Returns

JsonSchema: A generated JsonSchema.

Remarks

The schema for a type is generated once and then handed out for every subsequent request. Generating one walks the whole type graph reflectively - every property, its nullability, its compliance metadata and any derived types - which is work that cannot change while the process is running, because the answer is a function of the CLR type alone.

Without the memo this is recomputed per call, and the callers that matter call it per *instance* rather than per type: the read model compliance release pass asks for the schema once for every instance it releases, so serving a collection of a thousand read models generated the same schema a thousand times - measured at roughly a quarter of a second of pure waste for a read model of moderate size, on every emission of an observable query, for every subscriber.

Sharing one instance is consistent with how a JsonSchema is already treated everywhere else: the client's event-type schemas are cached and read concurrently on the same assumption, that a schema is effectively immutable once built. Its own derived answers are memoized internally with release semantics, so concurrent readers of a shared instance are safe.

Generate(Type, IEventTypes)

Generates a precise event schema using the owning store's event identities.

public JsonSchema Generate(Type type, IEventTypes eventTypes)

Parameters

type Type: The event type.
eventTypes IEventTypes: The owning store's finalized event registry.

Returns

JsonSchema: The generated schema.

Exceptions

RegistryAwareEventTypeSchemasNotSupported: The generator does not support a required explicit compensation binding.

GenerateForReadModel(Type)

Generate a JsonSchema for a read model type.

public JsonSchema GenerateForReadModel(Type type)

Parameters

type Type: Read model Type to generate for.

Returns

JsonSchema: A generated JsonSchema.

Remarks

Uses the same precise shape as Generate(Type).

GenerateLegacyEventType(Type)

Generates the legacy event schema for a kernel without precise schema support.

public JsonSchema GenerateLegacyEventType(Type type)

Parameters

type Type: The event type.

Returns

JsonSchema: The legacy schema.

Remarks

Preserves the default-only shape used by kernels that do not advertise precise event type schemas. This representation is only used when registering against those kernels, not for read models.

Exceptions

LegacyEventTypeSchemasNotSupported: The generator does not support legacy event schemas.

GenerateLegacyEventType(Type, IEventTypes)

Generates a legacy event schema using the owning store's event identities.

public JsonSchema GenerateLegacyEventType(Type type, IEventTypes eventTypes)

Parameters

type Type: The event type.
eventTypes IEventTypes: The owning store's finalized event registry.

Returns

JsonSchema: The generated legacy schema.

Exceptions

RegistryAwareEventTypeSchemasNotSupported: The generator does not support a required explicit compensation binding.