Notifications

Overview (C4 Component)

Black-box description of components

Component	Responsibility (why does it exist?)	Provided interface(s)	Consumed interface(s)
AsyncConfig	Declares the notificationExecutor bean (fixed-size ThreadPoolTaskExecutor) used for non-blocking Web-Socket pushes.	Spring @Configuration	—
notificationExecutor	Executes long-running or blocking tasks (WS broadcasts, e-mail) outside HTTP threads.	Executor bean	— (created by AsyncConfig)
MailConfig	Creates and wires JavaMailSender, SpringTemplateEngine and a ClassLoaderTemplateResolver for HTML templates under templates/email/.	Spring @Configuration	SMTP host/port/credentials in spring.mail.* properties
JavaMailSender	Low–level SMTP client that actually sends the MIME messages.	JavaMailSender	SMTP server
SpringTemplateEngine	Renders Thymeleaf email templates with dynamic context.	SpringTemplateEngine	—
WebSocketConfig	Registers STOMP endpoints (/ws, SockJS fallback) and the in-memory SimpleBroker (/topic/**).	Spring WebSocketMessageBrokerConfigurer	WebSocketSecurityConfig
Spring SimpleBroker	In-memory message broker that multicasts frames published to /topic/** to connected clients.	STOMP broker	—
WebSocketSecurityConfig	Adds the JWT handshake interceptor, security context propagation and an (optional) authorization manager for WS frames.	WebSocketMessageBrokerConfigurer beans (ChannelInterceptor, AuthorizationChannelInterceptor)	JwtAuthentificationService, Spring Security context
DomainEventPublisher	Utility wrapper around Spring ApplicationEventPublisher used by all bounded-contexts to emit domain events.	publish(Object)	Spring event bus
NotificationServiceImpl	Central domain-event listener. Decides template, recipients & content, then delegates to in-app push + e-mail.	@EventListener methods	InAppNotificationService, MailService
InAppNotificationService	Persistence + delivery of notifications: saves the entity, converts to DTO, and schedules Web-Socket broadcast.	pushToUser, pushToProvider	NotificationRepository, NotificationMapper, NotificationMessagePublisher
NotificationRepository	CRUD access to Notification table with convenience finders (top 20, unread-only, provider/user scope).	Spring-Data JPA	MySQL (via Hibernate)
NotificationMapper	MapStruct mapper between Notification entity and NotificationResponse DTO.	toDto (single & list)	—
NotificationMessagePublisher	Sends a DTO to /topic/users/{id} or /topic/providers/{opsCode} asynchronously via SimpMessagingTemplate.	sendUserNotification, sendProviderNotification (annotated @Async)	notificationExecutor, Spring SimpleBroker
MailService (MailSenderServiceImpl)	Composes an HTML e-mail (Thymeleaf) and delivers it through JavaMailSender.	sendHtmlMail(to, subject, template, ctx)	JavaMailSender, SpringTemplateEngine
NotificationController	REST façade: lists the last 20 notifications and marks one as read/unread.	GET /v1/notifications, PATCH /v1/notifications/{id}	NotificationService, CurrentUserService
NotificationService	Authorisation + orchestration layer for REST: filters by AuthInfo, calls repository and mapper.	list(AuthInfo, unreadOnly), markRead(AuthInfo,id,flag)	NotificationRepository, NotificationMapper
CurrentUserService	Supplies AuthInfo (userId, providerOpsCode, roles) to the REST layer.	authInfo()	Spring Security context

Important internal interfaces

Name	Signature / Protocol	Notes
Domain event contract	POJOs such as QuoteCreatedEvent, RequestForQuotationStatusChangedEvent, … published via DomainEventPublisher.publish(event)	Decouples bounded-contexts. Only the event type & minimal IDs travel across modules.
NotificationServiceImpl listeners	@EventListener public void on(QuoteCreatedEvent e) (same for each event)	Translates a domain event into a title, message, targetUrl and NotificationContext map for e-mail.
In-app push (provider)	pushToProvider(String opsCode, String title, String msg, String url)	Persists a provider-scoped notification, then broadcasts over WS.
In-app push (user)	pushToUser(Long userId, …)	Same as above but user-scoped.
WS broadcast	NotificationMessagePublisher.sendProviderNotification(opsCode, dto) → convertAndSend("/topic/providers/{opsCode}", dto)	Executed on notificationExecutor; each browser already subscribed receives a STOMP MESSAGE.
E-mail delivery	MailService.sendHtmlMail(to, subject, template, ctx)	Renders templates/email/{template}.html with the supplied context.
REST – list	`GET /v1/notifications?unreadOnly=true or false`	Returns up to 20 NotificationResponse, newest first; scope (user vs provider) inferred from JWT.
REST – mark read	PATCH /v1/notifications/{id} body \{ "read": true or false \}\	Toggles the read flag after ownership check; returns 204 No Content.
STOMP subscription (browser)	SUBSCRIBE /topic/users/{userId} or /topic/providers/{opsCode} (after /ws CONNECT)	Delivers real-time JSON payloads (NotificationResponse) that the SPA shows as toasts.
JWT handshake	Browser CONNECT frame with header Authorization: Bearer <jwt>	Accepted/rejected by JwtChannelInterceptor; establishes Principal for subsequent SUBSCRIBE frames.