Test Service

Service Types Have Different Testing Strategies

Services fall into two categories with different testing approaches:

Type	Testing Strategy	Skill
Resource Service	Mock repository, test authorization + events	test-resource-service
Utility Service	Mock external APIs (fetch), test error handling	test-utility-service

When to Test

Test services after you have:

1. Created the service (create-resource-service or create-utility-service)
2. Created any dependencies (repositories, schemas)

Which Skill to Use

Use test-resource-service when:

• Testing services that extend BaseService
• Testing CRUD operations on domain entities
• Testing authorization logic (admin vs owner vs other)
• Testing event emission

Examples: NoteService, UserService, CourseService

Use test-utility-service when:

• Testing services that call external APIs
• Testing authentication/authorization logic services
• Testing error handling for external failures
• Mocking fetch or other network calls

Examples: AuthenticationService, AuthorizationService, EmailService

Common Testing Patterns

Both service types share these patterns:

User Context Fixtures

const adminUser: AuthenticatedUserContextType = {
  userId: "admin-1",
  globalRole: "admin",
};
const regularUser: AuthenticatedUserContextType = {
  userId: "user-1",
  globalRole: "user",
};
const otherUser: AuthenticatedUserContextType = {
  userId: "user-2",
  globalRole: "user",
};

Error Assertions

// Expect specific error type
await expect(service.someMethod()).rejects.toThrow(UnauthorizedError);

// Expect any error
await expect(service.someMethod()).rejects.toThrow();

Cleanup in beforeEach/afterEach

beforeEach(() => {
  // Reset state
});

afterEach(() => {
  vi.restoreAllMocks();
});

See Also

• test-resource-service - Testing resource services (CRUD + events)
• test-utility-service - Testing utility services (external APIs)