Added stats endpoint

src/main/java/org/ros/chatto/controller/StatisticsController.java

@@ -0,0 +1,29 @@
+package org.ros.chatto.controller;
+
+import java.time.Instant;
+
+import org.ros.chatto.dto.StatsDTO;
+import org.ros.chatto.service.StatisticsService;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequestMapping("/api/stats")
+@RequiredArgsConstructor
+public class StatisticsController {
+    private final StatisticsService statisticsService;
+
+    @GetMapping
+    public StatsDTO rootStats() {
+        return StatsDTO.builder()
+                .totalMessages(statisticsService.totalMessage())
+                .totalOnlineUsers(statisticsService.totalUsersOnline())
+                .numMessagesToday(
+                        statisticsService.messagesOnDay(Instant.now()))
+                .totalUsers(statisticsService.totalUsers()).build();
+    }
+
+}

src/main/java/org/ros/chatto/dto/StatsDTO.java

@@ -0,0 +1,21 @@
+package org.ros.chatto.dto;
+
+import lombok.Builder;
+import lombok.Getter;
+
+@Builder
+@Getter
+public class StatsDTO {
+    @Builder.Default
+    private long totalUsers = 0;
+
+    @Builder.Default
+    private long totalOnlineUsers = 0;
+
+    @Builder.Default
+    private long totalMessages = 0;
+
+    @Builder.Default
+    private long numMessagesToday = 0;
+
+}

src/main/java/org/ros/chatto/service/StatisticsService.java

@@ -6,11 +6,13 @@ import org.ros.chatto.repository.ChatMessageRepository;
 import org.ros.chatto.repository.UserRepository;
 import org.ros.chatto.repository.UserSessionRepository;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 
 import lombok.RequiredArgsConstructor;
 
 @RequiredArgsConstructor
 @Service
+@Transactional(readOnly = true)
 public class StatisticsService {
     private final ChatMessageRepository chatMessageRepository;
     private final UserRepository userRepo;