Implement project summary endpoint

src/main/java/net/hackyourfuture/tickettrackingsystem/TicketTrackingSystemApplication.java

@@ -6,7 +6,7 @@
 @SpringBootApplication
 public class TicketTrackingSystemApplication {
 
-	public static void main(String[] args) {
+	static void main(String[] args) {
 		SpringApplication.run(TicketTrackingSystemApplication.class, args);
 	}
 

src/main/java/net/hackyourfuture/tickettrackingsystem/controller/ProjectController.java

@@ -0,0 +1,23 @@
+package net.hackyourfuture.tickettrackingsystem.controller;
+
+import lombok.RequiredArgsConstructor;
+import net.hackyourfuture.tickettrackingsystem.dto.response.ProjectSummaryResponse;
+import net.hackyourfuture.tickettrackingsystem.service.ProjectService;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.List;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/projects")
+public class ProjectController {
+
+    private final ProjectService projectService;
+
+    @GetMapping
+    public List<ProjectSummaryResponse> getAllProjects() {
+        return projectService.getAllProjects();
+    }
+}

src/main/java/net/hackyourfuture/tickettrackingsystem/dto/response/ProjectSummaryResponse.java

@@ -0,0 +1,10 @@
+package net.hackyourfuture.tickettrackingsystem.dto.response;
+
+public record ProjectSummaryResponse(
+        Long id,
+        String name,
+        int openTickets,
+        int inProgressTickets,
+        int closedTickets
+) {
+}

src/main/java/net/hackyourfuture/tickettrackingsystem/repository/ProjectRepository.java

@@ -0,0 +1,40 @@
+package net.hackyourfuture.tickettrackingsystem.repository;
+
+import lombok.RequiredArgsConstructor;
+import net.hackyourfuture.tickettrackingsystem.dto.response.ProjectSummaryResponse;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.jdbc.core.RowMapper;
+import org.springframework.stereotype.Repository;
+
+import java.util.List;
+
+@Repository
+@RequiredArgsConstructor
+public class ProjectRepository {
+    private final JdbcTemplate jdbcTemplate;
+
+    public List<ProjectSummaryResponse> findAllProjectSummaries(){
+        String sql = """
+                SELECT
+                p.id,
+                p.name,
+                COUNT(*) FILTER (WHERE t.status = 'OPEN') AS open_tickets,
+                COUNT(*) FILTER (WHERE t.status = 'IN_PROGRESS') AS in_progress_tickets,
+                COUNT(*) FILTER (WHERE t.status = 'CLOSED') AS closed_tickets
+                FROM projects p
+                LEFT JOIN tickets t ON p.id = t.project_id
+                GROUP BY p.id, p.name
+                ORDER BY p.name
+                """;
+        return jdbcTemplate.query(sql, projectSummaryResponseRowMapper);
+    }
+
+    private final RowMapper<ProjectSummaryResponse> projectSummaryResponseRowMapper =
+            (rs, rowNum) -> new ProjectSummaryResponse(
+                    rs.getLong("id"),
+                    rs.getString("name"),
+                    rs.getInt("open_tickets"),
+                    rs.getInt("in_progress_tickets"),
+                    rs.getInt("closed_tickets")
+            );
+}

src/main/java/net/hackyourfuture/tickettrackingsystem/service/ProjectService.java

@@ -0,0 +1,19 @@
+package net.hackyourfuture.tickettrackingsystem.service;
+
+import lombok.RequiredArgsConstructor;
+import net.hackyourfuture.tickettrackingsystem.dto.response.ProjectSummaryResponse;
+import net.hackyourfuture.tickettrackingsystem.repository.ProjectRepository;
+import org.springframework.stereotype.Service;
+
+import java.util.List;
+
+@Service
+@RequiredArgsConstructor
+public class ProjectService {
+
+    private final ProjectRepository projectRepository;
+
+    public List<ProjectSummaryResponse> getAllProjects() {
+        return projectRepository.findAllProjectSummaries();
+    }
+}

src/main/resources/db/schema.sql

@@ -9,7 +9,7 @@ CREATE TABLE users (
 );
 CREATE TABLE projects (
     id bigserial primary key ,
-    name varchar(255) not null,CHECK (char_length(name) >= 3)
+    name varchar(255) not null CHECK (char_length(name) >= 3)
 );
 CREATE TABLE tickets (
     id bigserial primary key ,
@@ -21,7 +21,7 @@ CREATE TABLE tickets (
     update_date TIMESTAMP,
     CONSTRAINT fk_ticket_project
         FOREIGN KEY (project_id)
-            REFERENCES project(id)
+            REFERENCES projects(id)
 
 );
 
@@ -37,15 +37,15 @@ CREATE TABLE user_ticket (
             ON DELETE CASCADE,
     CONSTRAINT fk_user_ticket_ticket
         FOREIGN KEY (ticket_id)
-            REFERENCES ticket(id)
+            REFERENCES tickets(id)
             ON DELETE CASCADE
     );
 
 CREATE INDEX idx_tickets_status
-    ON ticket(status);
+    ON tickets(status);
 
 CREATE INDEX idx_tickets_project_id
-    ON ticket(project_id);
+    ON tickets(project_id);
 
 CREATE INDEX idx_user_ticket_user_id
     ON user_ticket(user_id);