Type Alias: ScopedBus<Namespace, Subjects, FilterPayload>

Makaio Framework

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Makaio Framework / bus-core / ScopedBus

Type Alias: ScopedBus<Namespace, Subjects, FilterPayload>

ScopedBus<Namespace, Subjects, FilterPayload> = IScopedBusBase<Namespace> & object

Defined in: ../../../packages/bus-core/src/scoped-bus.ts:14

Scoped bus with namespace isolation and type-safe filtering.

Type Declaration

getContext()

getContext(): MakaioBusContext

Get the bus context for advanced use cases.

Returns

MakaioBusContext

withFilter()

withFilter(filter): IFilteredBus<Namespace, Subjects, FilterPayload>

Create a filtered bus with a base payload filter.

The filter is automatically applied to all on() and once() calls.

When FilterPayload is known (via BusNamespace.scopedBus()), filter keys are automatically constrained to the intersection of all subject payloads.

Parameters

filter

TypedPayloadFilter<FilterPayload>

Base filter to apply to all subscriptions

Returns

IFilteredBus<Namespace, Subjects, FilterPayload>

FilteredBus with the specified filter

Example

// Type-safe filtering - keys auto-inferred from pre-computed FilterPayload
const scopedBus = await CodexMcpNamespace.scopedBus();
scopedBus.withFilter({ agentId: this.agentId }); // ✅ agentId validated
scopedBus.withFilter({ unknownKey: 'x' });       // ❌ Error - unknown key

// Explicit type override still works
interface CustomPayload { agentId: string; sessionId: string }
scopedBus.withFilter<CustomPayload>({ agentId: 'x' });

Type Parameters

Namespace

Namespace extends string

The namespace domain string (e.g., ‘adapter:codex-mcp’)

Subjects

Subjects = SubjectRecord

SubjectRecord for payload types (used by on/once/emit)

FilterPayload

FilterPayload = unknown

Pre-computed intersection of all filterable payloads. When provided, withFilter constrains filter keys to this type.

Type Composition

• ScopedBus

  • `IScopedBusBase & { /**
  • Create a filtered bus with a base payload filter.
  • The filter is automatically applied to all on() and once() calls.
  • When FilterPayload is known (via BusNamespace.scopedBus()), filter keys are
  • automatically constrained to the intersection of all subject payloads.
  • @param filter - Base filter to apply to all subscriptions
  • @returns FilteredBus with the specified filter
  • @example
  • // Type-safe filtering - keys auto-inferred from pre-computed FilterPayload
  • const scopedBus = await CodexMcpNamespace.scopedBus();
  • scopedBus.withFilter({ agentId: this.agentId }); // ✅ agentId validated
  • scopedBus.withFilter({ unknownKey: ‘x’ }); // ❌ Error - unknown key
  • // Explicit type override still works
  • interface CustomPayload { agentId: string; sessionId: string }
  • scopedBus.withFilter({ agentId: ‘x’ });

  */ withFilter(filter: TypedPayloadFilter): IFilteredBus<Namespace, Subjects, FilterPayload>;

  /**

  • Get the bus context for advanced use cases. */ getContext(): MakaioBusContext; }`
  • IScopedBusBase<Namespace>
    • Namespace
  • `{ /**
  • Create a filtered bus with a base payload filter.
  • The filter is automatically applied to all on() and once() calls.
  • When FilterPayload is known (via BusNamespace.scopedBus()), filter keys are
  • automatically constrained to the intersection of all subject payloads.
  • @param filter - Base filter to apply to all subscriptions
  • @returns FilteredBus with the specified filter
  • @example
  • // Type-safe filtering - keys auto-inferred from pre-computed FilterPayload
  • const scopedBus = await CodexMcpNamespace.scopedBus();
  • scopedBus.withFilter({ agentId: this.agentId }); // ✅ agentId validated
  • scopedBus.withFilter({ unknownKey: ‘x’ }); // ❌ Error - unknown key
  • // Explicit type override still works
  • interface CustomPayload { agentId: string; sessionId: string }
  • scopedBus.withFilter({ agentId: ‘x’ });

  */ withFilter(filter: TypedPayloadFilter): IFilteredBus<Namespace, Subjects, FilterPayload>;

  /**

  • Get the bus context for advanced use cases. */ getContext(): MakaioBusContext; }`

Resolved Shape

type ScopedBus = {
  namespace: Namespace;
  on: <Subject extends ScopedSubjectDefinition<Namespace>>(subject: Subject, handler: HandlerForSubjectDefinition<Subject>, options?: OnOptions) => () => void;
  intercept: <Subject extends ScopedSubjectDefinition<Namespace>>(subject: Subject, handler: InterceptorHandler<Subject['$meta']['payload']>, options?: InterceptOptions) => () => void;
  once: { <Subject extends ScopedSubjectDefinition<Namespace>>(subject: Subject, handler: HandlerForSubjectDefinition<Subject>): () => void; <Subject extends ScopedSubjectDefinition<Namespace>>(subject: Subject, options?: OnceOptions<Subject> | undefined): Promise<ContextForSubjectDefinition<Subject>>; };
  emit: <Subject extends ScopedSubjectDefinition<Namespace>>(subject: Subject, payload: Subject['$meta']['payload']) => Promise<void>;
  request: <Subject extends ScopedSubjectDefinition<Namespace>>(subject: Subject, payload: Subject['$meta']['payload']['request']) => Promise<Subject['$meta']['payload']['response']>;
  requestOptional: <Subject extends ScopedSubjectDefinition<Namespace>>(subject: Subject, payload: Subject['$meta']['payload']['request']) => Promise<OptionalResult<Subject['$meta']['payload']['response']>>;
  withFilter: (filter: TypedPayloadFilter<FilterPayload>) => IFilteredBus<Namespace, Subjects, FilterPayload>;
  getContext: () => MakaioBusContext;
};