Factory

Definition

The Factory pattern encapsulates complex object creation logic behind simple functions. Callers provide minimal configuration and receive ready-to-use instances without knowing initialization details.

This is the dominant pattern in granit-front — every package exposes at least one factory.

Diagram

graph LR
    Config["Config object"] --> Factory["createXxx()"]
    Factory --> Instance["Ready-to-use instance"]

Implementation in Granit

Factory	Package	Creates
createLogger(prefix, options?)	@granit/logger	Logger with configured transports
createApiClient(config)	@granit/api-client	Axios instance with Bearer interceptor
createAuthContext<T>()	@granit/react-authentication	Generic, type-safe auth context + hook
createLocalization(config?)	@granit/localization	Isolated i18next instance
createReactLocalization(config?)	@granit/react-localization	i18next with initReactI18next plugin
createSignalRTransport(config)	@granit/notifications-signalr	SignalR notification transport
createSseTransport(config)	@granit/notifications-sse	SSE notification transport
createKlaroCookieConsentProvider(options)	@granit/cookies-klaro	Klaro CMP adapter
createStorage<T>(key, options?)	@granit/storage	Typed localStorage/sessionStorage accessor
createMockProvider<T>()	@granit/react-authentication	Test provider using same context

Rationale

Factory functions keep the public API surface minimal while hiding initialization complexity (transport wiring, plugin injection, default configuration). They also enable tree-shaking — unused factories are eliminated at build time.

Usage example

import { createLogger } from '@granit/logger';
import { createApiClient } from '@granit/api-client';
import { createAuthContext } from '@granit/react-authentication';
import type { BaseAuthContextType } from '@granit/authentication';

// Logger with console transport
const logger = createLogger('app');

// HTTP client with automatic Bearer injection
const api = createApiClient({ baseURL: import.meta.env.VITE_API_URL });

// Typed auth context for the application
interface AuthContextType extends BaseAuthContextType {
  register: () => void;
}
export const { AuthContext, useAuth } = createAuthContext<AuthContextType>();

Further reading

• Factory Method — refactoring.guru