Added notifications system

build.gradle

@@ -47,4 +47,9 @@ dependencies {
 tasks.named('test') {
 	useJUnitPlatform()
 }
+
+tasks.named('compileJava') {
+	inputs.files(tasks.named('processResources'))
+}
+
 targetCompatibility = JavaVersion.VERSION_17

src/main/java/site/easystartup/web/config/AppConfig.java

@@ -1,11 +1,13 @@
 package site.easystartup.web.config;
 
 import org.modelmapper.ModelMapper;
+import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
 import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.stereotype.Component;
 
 @Configuration
 @ComponentScan(basePackages = {"site.easystartup.web"})

src/main/java/site/easystartup/web/config/WebSocketConfig.java

@@ -1,4 +1,4 @@
-package site.easystartup.web.chat.config;
+package site.easystartup.web.config;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import org.springframework.context.annotation.Configuration;
@@ -19,7 +19,7 @@ public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
 
     @Override
     public void configureMessageBroker(MessageBrokerRegistry config) {
-        config.enableSimpleBroker( "/user");
+        config.enableSimpleBroker( "/user", "/queue");
         config.setApplicationDestinationPrefixes("/app");
         config.setUserDestinationPrefix("/user");
     }

src/main/java/site/easystartup/web/notification/controller/NotificationController.java

@@ -0,0 +1,28 @@
+package site.easystartup.web.notification.controller;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.messaging.handler.annotation.Payload;
+import org.springframework.messaging.simp.SimpMessagingTemplate;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.GetMapping;
+import site.easystartup.web.notification.domian.Notification;
+
+import java.security.Principal;
+import java.util.logging.Logger;
+
+@Controller
+@RequiredArgsConstructor(onConstructor_ = @Autowired)
+public class NotificationController {
+    private final SimpMessagingTemplate messagingTemplate;
+    Logger logger = Logger.getGlobal();
+
+    @GetMapping("/notify")
+    public void notification(Principal principal, @Payload Notification notification) {
+        logger.info("Web socket sent notification to " + principal.getName());
+        messagingTemplate.convertAndSendToUser(principal.getName(), "queue/notification", notification);
+    }
+
+
+
+}

src/main/java/site/easystartup/web/notification/domian/Notification.java

@@ -0,0 +1,10 @@
+package site.easystartup.web.notification.domian;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+@Data
+@AllArgsConstructor
+public class Notification {
+    private String text;
+}

src/main/java/site/easystartup/web/notification/event/EventHandler.java

@@ -0,0 +1,12 @@
+package site.easystartup.web.notification.event;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+
+@Target(ElementType.METHOD)
+public @interface EventHandler {
+}

src/main/java/site/easystartup/web/notification/event/NotificationEvent.java

@@ -0,0 +1,9 @@
+package site.easystartup.web.notification.event;
+
+public interface NotificationEvent {
+    void invoke();
+
+    String getRecipient();
+
+    String getMessage();
+}

src/main/java/site/easystartup/web/notification/event/NotificationEventManager.java

@@ -0,0 +1,36 @@
+package site.easystartup.web.notification.event;
+
+import org.springframework.context.annotation.Scope;
+import org.springframework.stereotype.Component;
+
+import java.lang.reflect.InvocationTargetException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+@Component
+@Scope("singleton")
+public class NotificationEventManager {
+    private List<NotificationListener> listeners = new ArrayList<>();
+
+    public void registerListener(NotificationListener listener) {
+        listeners.add(listener);
+    }
+
+    public void removeListener(NotificationListener listener) {
+        listeners.remove(listener);
+    }
+
+    public void notifyListeners(Class<? extends NotificationEvent> event) {
+        listeners.forEach(listener -> Arrays.stream(listener.getClass().getMethods()).
+                filter(m -> m.isAnnotationPresent(EventHandler.class)).forEach(method -> {
+                    if (method.getParameterTypes()[0].equals(event.getClass())) {
+                        try {
+                            method.invoke(listener, event);
+                        } catch (IllegalAccessException | InvocationTargetException e) {
+                            throw new RuntimeException(e);
+                        }
+                    }
+                }));
+    }
+}

src/main/java/site/easystartup/web/notification/event/NotificationListener.java

@@ -0,0 +1,4 @@
+package site.easystartup.web.notification.event;
+
+public interface NotificationListener {
+}

src/main/java/site/easystartup/web/notification/event/realtime/RealTimeListener.java

@@ -0,0 +1,22 @@
+package site.easystartup.web.notification.event.realtime;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Autowired;
+import site.easystartup.web.notification.domian.Notification;
+import site.easystartup.web.notification.event.EventHandler;
+import site.easystartup.web.notification.event.NotificationEvent;
+import site.easystartup.web.notification.event.NotificationListener;
+import site.easystartup.web.notification.service.NotificationService;
+import site.easystartup.web.post.domain.event.RepostEvent;
+
+@RequiredArgsConstructor(onConstructor_ = @Autowired)
+public class RealTimeListener implements NotificationListener {
+    private final NotificationService notificationService;
+
+    //Обрабатывает все ивенты
+    @EventHandler
+    public void onEvent(NotificationEvent event) {
+        notificationService.sendNotification(
+                new Notification(event.getMessage()));
+    }
+}

src/main/java/site/easystartup/web/notification/service/NotificationService.java

@@ -0,0 +1,17 @@
+package site.easystartup.web.notification.service;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.messaging.simp.SimpMessagingTemplate;
+import org.springframework.stereotype.Component;
+import site.easystartup.web.notification.domian.Notification;
+
+@Component
+@RequiredArgsConstructor(onConstructor_ = @Autowired)
+public class NotificationService {
+    private final SimpMessagingTemplate messagingTemplate;
+
+    public void sendNotification(Notification notification) {
+        messagingTemplate.convertAndSendToUser("server", "queue/notification", notification);
+    }
+}

src/main/java/site/easystartup/web/post/domain/event/RepostEvent.java

@@ -0,0 +1,27 @@
+package site.easystartup.web.post.domain.event;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Autowired;
+import site.easystartup.web.notification.event.NotificationEvent;
+import site.easystartup.web.notification.event.NotificationEventManager;
+
+@RequiredArgsConstructor
+public class RepostEvent implements NotificationEvent {
+    @Autowired
+    private NotificationEventManager notificationEventManager;
+
+    @Getter
+    private final String recipient;
+
+    @Getter
+    private final String reportedUser;
+
+    @Getter
+    private final String message;
+
+    @Override
+    public void invoke() {
+        notificationEventManager.notifyListeners(getClass());
+    }
+}

src/main/java/site/easystartup/web/post/service/PostService.java

@@ -3,6 +3,7 @@ package site.easystartup.web.post.service;
 import lombok.RequiredArgsConstructor;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
+import site.easystartup.web.post.domain.event.RepostEvent;
 import site.easystartup.web.post.domain.exception.AlreadyLikedException;
 import site.easystartup.web.post.domain.exception.PostNotFoundException;
 import site.easystartup.web.post.domain.model.Post;
@@ -61,6 +62,9 @@ public class PostService {
             List<Long> answers = answered.getAnswers() != null ? answered.getAnswers() : new ArrayList<>();
             answers.add(post.getId());
             answered.setAnswers(answers);
+            new RepostEvent(answered.getSender(),
+                    post.getSender(),
+                    String.format("Пользователь %s ответил на вашу запись!", answered.getSender())).invoke();
             postRepo.save(answered);
         }
     }