Client configuration and metadata

Use QueryClientFactory<S,FIELDS,DomainEventBody> when snapshot, event and historical-state clients share an aggregate route. Pass QueryClientOptions once and override options per create method. Construction only composes metadata; it does not discover a server, request schema, or validate a deployment.

Input / method	Contract
contextAlias, resourceAttribution, aggregateName	Joined in this order to make basePath; absent parts are empty.
basePath	Explicit value overrides the composed path, including an explicit empty string.
Other ApiMetadata options	Forwarded to decorator execution, including fetcher and request options.
createSnapshotQueryClient	SnapshotQueryClient<S,FIELDS>
createLoadStateAggregateClient	LoadStateAggregateClient<S>
createLoadOwnerStateAggregateClient	LoadOwnerStateAggregateClient<S>
createEventStreamQueryClient<EVENT_FIELDS>	EventStreamQueryClient<DomainEventBody,EVENT_FIELDS>; event fields are separate from the factory's snapshot FIELDS.

Per-call options shallowly override constructor defaults. The route composition is internal; read the result from a client's apiMetadata.basePath if you need it. Supply actual URL path values through the request configuration when a ResourceAttributionPathSpec contains {tenantId} or {ownerId}. Missing Fetcher registration and request failures belong to decorator/Fetcher execution; no I/O or cleanup occurs when creating these wrappers.

WowMetadata is a data model with description and contexts keyed by name. Each BoundedContext has alias, scopes and aggregates; an Aggregate has type, tenantId, id, scopes, command names and event names. Nullable metadata values are explicit nulls. new WowMetadataClient(apiMetadata?).metadata(attributes?, abort?) reads it from GET /wow/metadata, relative to the Fetcher's base URL; nothing reads it automatically, and this module exports no wow() decorator. Read commands and snapshot queries for execution.

Complete example

import { Fetcher } from '@ahoo-wang/fetcher';
import { QueryClientFactory, WowMetadataClient } from '@ahoo-wang/wow-client';
interface User {
  id: string;
  name: string;
}
const fetcher = new Fetcher({ baseURL: 'https://api.example.com/' });
const factory = new QueryClientFactory<User>({
  fetcher,
  contextAlias: 'accounts',
  aggregateName: 'user',
});
const snapshots = factory.createSnapshotQueryClient(); // basePath accounts/user
const history = factory.createLoadStateAggregateClient();
export async function listContexts() {
  const metadata = await new WowMetadataClient({ fetcher }).metadata();
  return Object.keys(metadata.contexts);
}
export { snapshots, history };

Service URLs in examples require application endpoints; type checking does not imply an external service was contacted.

Public signatures and types

These signatures follow declarations reachable from the current root entry. ? marks optional input; generics/interfaces only constrain compile-time types. Locate inherited and related types through the symbol index. Runtime defaults and failure behavior are described above.

ScopesCapable

export interface ScopesCapable {
  scopes: string[];
}

typescript/wow-client/src/configuration/wowMetadata.ts:16

Aggregate

export interface Aggregate extends ScopesCapable {
  type: string | null;
  tenantId: string | null;
  id: string | null;
  commands: string[];
  events: string[];
}

typescript/wow-client/src/configuration/wowMetadata.ts:20

BoundedContext

export interface BoundedContext extends ScopesCapable, DescriptionCapable {
  alias: string | null;
  aggregates: Record<string, Aggregate>;
}

typescript/wow-client/src/configuration/wowMetadata.ts:43

WowMetadata

export interface WowMetadata extends DescriptionCapable {
  contexts: Record<string, BoundedContext>;
}

typescript/wow-client/src/configuration/wowMetadata.ts:48

WowMetadataClient

export class WowMetadataClient implements ApiMetadataCapable {
    constructor(public readonly apiMetadata?: ApiMetadata);
    metadata(attributes?: Record<string, unknown>, abort?: AbortController | AbortSignal): Promise<WowMetadata>;
}

typescript/wow-client/src/configuration/wowMetadataClient.ts:38

QueryClientOptions

export interface QueryClientOptions
  extends
    PartialBy<ApiMetadata, 'basePath'>,
    Partial<AliasBoundedContext>,
    Partial<AggregateNameCapable> {
  contextAlias?: string;
  resourceAttribution?: ResourceAttributionPathSpec;
}

typescript/wow-client/src/query/queryClients.ts:34

QueryClientFactory

export class QueryClientFactory<S, FIELDS extends string = string, DomainEventBody = any> {
    constructor(private readonly defaultOptions: QueryClientOptions);
    createSnapshotQueryClient(options?: QueryClientOptions): SnapshotQueryClient<S, FIELDS>;
    createLoadStateAggregateClient(options?: QueryClientOptions): LoadStateAggregateClient<S>;
    createLoadOwnerStateAggregateClient(options?: QueryClientOptions): LoadOwnerStateAggregateClient<S>;
    createEventStreamQueryClient<EVENT_FIELDS extends string = string>(options?: QueryClientOptions): EventStreamQueryClient<DomainEventBody, EVENT_FIELDS>;
}

typescript/wow-client/src/query/queryClients.ts:63

Related topics

Commands and wait results · Snapshot queries · Filter expressions and legacy conditions · Projection, sorting and pagination · Cursor queries · Aggregation builders · Events and historical state · Identity and resource attribution