Monera A

postify/pom.xml

@@ -35,19 +35,26 @@
 			<artifactId>spring-boot-starter-webmvc</artifactId>
 		</dependency>
 
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-jdbc</artifactId>
+		</dependency>
+
 		<dependency>
 			<groupId>org.postgresql</groupId>
 			<artifactId>postgresql</artifactId>
 			<scope>runtime</scope>
 		</dependency>
+
 		<dependency>
 			<groupId>org.projectlombok</groupId>
 			<artifactId>lombok</artifactId>
 			<optional>true</optional>
 		</dependency>
+
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
-			<artifactId>spring-boot-starter-webmvc-test</artifactId>
+			<artifactId>spring-boot-starter-test</artifactId>
 			<scope>test</scope>
 		</dependency>
 	</dependencies>

postify/src/main/java/net/hackyourfuture/backend/week6/postify/config/WebClientConfig.java

@@ -0,0 +1,16 @@
+package net.hackyourfuture.backend.week6.postify.config;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.client.RestClient;
+
+@Configuration
+public class WebClientConfig {
+
+    @Bean
+    public RestClient lyricsRestClient() {
+        return RestClient.builder()
+                .baseUrl("https://api.lyrics.ovh/v1")
+                .build();
+    }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/controller/TrackController.java

@@ -0,0 +1,22 @@
+package net.hackyourfuture.backend.week6.postify.controller;
+
+import net.hackyourfuture.backend.week6.postify.dto.TrackLyricsDto;
+import net.hackyourfuture.backend.week6.postify.service.TrackLyricsService;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class TrackController {
+
+    private final TrackLyricsService trackLyricsService;
+
+    public TrackController(TrackLyricsService trackLyricsService) {
+        this.trackLyricsService = trackLyricsService;
+    }
+
+    @GetMapping("/tracks/{id}/lyrics")
+    public TrackLyricsDto getLyrics(@PathVariable("id") Long id) {
+        return trackLyricsService.getTrackLyrics(id);
+    }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/controller/UserStatsController.java

@@ -0,0 +1,20 @@
+package net.hackyourfuture.backend.week6.postify.controller;
+
+import lombok.RequiredArgsConstructor;
+import net.hackyourfuture.backend.week6.postify.dto.UserStatsDto;
+import net.hackyourfuture.backend.week6.postify.service.UserStatsService;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequiredArgsConstructor
+public class UserStatsController {
+
+    private final UserStatsService userStatsService;
+
+    @GetMapping("/users/{id}/stats")
+    public UserStatsDto getUserStats(@PathVariable("id") Integer id) {
+        return userStatsService.getUserStats(id);
+    }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/dto/ExternalLyricsResponse.java

@@ -0,0 +1,5 @@
+package net.hackyourfuture.backend.week6.postify.dto;
+
+public record ExternalLyricsResponse(String lyrics) {
+
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/dto/TrackLyricsDto.java

@@ -0,0 +1,25 @@
+package net.hackyourfuture.backend.week6.postify.dto;
+
+public class TrackLyricsDto {
+    private Long trackId;
+    private String trackTitle;
+    private String artistName;
+    private String lyrics;
+
+    public TrackLyricsDto(Long trackId, String trackTitle, String artistName, String lyrics) {
+        this.trackId = trackId;
+        this.trackTitle = trackTitle;
+        this.artistName = artistName;
+        this.lyrics = lyrics;
+    }
+
+    // Getters and Setters
+    public Long getTrackId() { return trackId; }
+    public void setTrackId(Long trackId) { this.trackId = trackId; }
+    public String getTrackTitle() { return trackTitle; }
+    public void setTrackTitle(String trackTitle) { this.trackTitle = trackTitle; }
+    public String getArtistName() { return artistName; }
+    public void setArtistName(String artistName) { this.artistName = artistName; }
+    public String getLyrics() { return lyrics; }
+    public void setLyrics(String lyrics) { this.lyrics = lyrics; }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/dto/UserStatsDto.java

@@ -0,0 +1,17 @@
+package net.hackyourfuture.backend.week6.postify.dto;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@Getter
+@AllArgsConstructor
+public class UserStatsDto {
+    private Integer userId;
+    private String userName;
+    private String userCountry;
+    private Long totalStreams;
+    private Long uniqueTracksStreamed;
+    private Long uniqueArtistsStreamed;
+    private Long totalListeningTimeSeconds;
+    private String favoriteGenre;
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/exception/GlobalExceptionHandler.java

@@ -0,0 +1,20 @@
+package net.hackyourfuture.backend.week6.postify.exception;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+import org.springframework.web.client.HttpClientErrorException;
+import java.util.Map;
+
+@RestControllerAdvice
+public class GlobalExceptionHandler {
+
+    // Catches any 404 errors thrown by RestClient when the external lyrics API comes up empty
+    @ExceptionHandler(HttpClientErrorException.NotFound.class)
+    public ResponseEntity<Map<String, String>> handleExternalLyricsNotFound(HttpClientErrorException.NotFound ex) {
+        return ResponseEntity
+                .status(HttpStatus.NOT_FOUND)
+                .body(Map.of("error", "The lyrics API does not have any lyrics available for this song."));
+    }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/repository/TrackRepository.java

@@ -0,0 +1,44 @@
+package net.hackyourfuture.backend.week6.postify.repository;
+
+import net.hackyourfuture.backend.week6.postify.dto.TrackLyricsDto;
+import org.springframework.dao.EmptyResultDataAccessException;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.stereotype.Repository;
+
+import java.util.Optional;
+
+@Repository
+public class TrackRepository {
+
+    private final JdbcTemplate jdbcTemplate;
+
+    public TrackRepository(JdbcTemplate jdbcTemplate) {
+        this.jdbcTemplate = jdbcTemplate;
+    }
+
+    public Optional<TrackLyricsDto> findTrackAndArtistById(Long trackId) {
+        String sql = """
+            SELECT t.track_id, t.track_title, a.artist_name 
+            FROM tracks t
+            JOIN albums al ON t.album_id = al.album_id
+            JOIN artists a ON al.artist_id = a.artist_id
+            WHERE t.track_id = ?
+        """;
+
+        try {
+            // If found, wrap the object inside a safe Optional box
+            TrackLyricsDto dto = jdbcTemplate.queryForObject(sql, (rs, rowNum) ->
+                    new TrackLyricsDto(
+                            rs.getLong("track_id"),
+                            rs.getString("track_title"),
+                            rs.getString("artist_name"),
+                            null // Lyrics are left empty for now
+                    ), trackId);
+            return Optional.ofNullable(dto);
+
+        } catch (EmptyResultDataAccessException e) {
+            // If the database finds nothing, return a safe empty box
+            return Optional.empty();
+        }
+    }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/repository/UserRepository.java

@@ -0,0 +1,77 @@
+package net.hackyourfuture.backend.week6.postify.repository;
+
+import lombok.RequiredArgsConstructor;
+import net.hackyourfuture.backend.week6.postify.dto.UserStatsDto;
+import org.springframework.stereotype.Repository;
+
+import javax.sql.DataSource;
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.Optional;
+
+@Repository
+@RequiredArgsConstructor
+public class UserRepository {
+
+    private final DataSource dataSource;
+
+    public Optional<UserStatsDto> getUserStats(Integer userId) {
+        String sql = """
+            SELECT 
+                u.user_id,
+                u.user_name,
+                u.user_country,
+                COUNT(s.stream_id) AS total_streams,
+                COUNT(DISTINCT s.track_id) AS unique_tracks,
+                COUNT(DISTINCT al.artist_id) AS unique_artists,
+                COALESCE(SUM(t.track_duration_s), 0) AS total_time,
+                (
+                    SELECT t2.genre 
+                    FROM streams s2
+                    JOIN tracks t2 ON s2.track_id = t2.track_id
+                    WHERE s2.user_id = u.user_id
+                    GROUP BY t2.genre
+                    ORDER BY COUNT(s2.stream_id) DESC, t2.genre ASC
+                    LIMIT 1
+                ) AS favorite_genre
+            FROM users u
+            LEFT JOIN streams s ON u.user_id = s.user_id
+            LEFT JOIN tracks t ON s.track_id = t.track_id
+            LEFT JOIN albums al ON t.album_id = al.album_id
+            WHERE u.user_id = ?
+            GROUP BY u.user_id, u.user_name, u.user_country;
+            """;
+
+        try (Connection connection = dataSource.getConnection();
+             PreparedStatement statement = connection.prepareStatement(sql)) {
+
+            statement.setInt(1, userId);
+
+            try (ResultSet resultSet = statement.executeQuery()) {
+                if (resultSet.next()) {
+                    if (resultSet.getString("user_name") == null) {
+                        return Optional.empty();
+                    }
+
+                    UserStatsDto dto = new UserStatsDto(
+                            resultSet.getInt("user_id"),
+                            resultSet.getString("user_name"),
+                            resultSet.getString("user_country"),
+                            resultSet.getLong("total_streams"),
+                            resultSet.getLong("unique_tracks"),
+                            resultSet.getLong("unique_artists"),
+                            resultSet.getLong("total_time"),
+                            resultSet.getString("favorite_genre")
+                    );
+                    return Optional.of(dto);
+                }
+            }
+        } catch (SQLException e) {
+            throw new RuntimeException("Database error occurred while fetching user statistics", e);
+        }
+
+        return Optional.empty();
+    }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/service/TrackLyricsService.java

@@ -0,0 +1,53 @@
+package net.hackyourfuture.backend.week6.postify.service;
+
+import net.hackyourfuture.backend.week6.postify.dto.ExternalLyricsResponse;
+import net.hackyourfuture.backend.week6.postify.dto.TrackLyricsDto;
+import net.hackyourfuture.backend.week6.postify.repository.TrackRepository;
+import org.springframework.http.HttpStatus;
+import org.springframework.stereotype.Service;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.client.RestClient;
+import org.springframework.web.server.ResponseStatusException;
+
+@Service
+public class TrackLyricsService {
+
+    private final TrackRepository trackRepository;
+    private final RestClient restClient;
+
+    public TrackLyricsService(TrackRepository trackRepository) {
+        this.trackRepository = trackRepository;
+        // Sets up the RestClient base URL pointing directly to the external lyrics provider
+        this.restClient = RestClient.builder()
+                .baseUrl("https://api.lyrics.ovh/v1")
+                .build();
+    }
+
+    public TrackLyricsDto getTrackLyrics(Long trackId) {
+        // 1. Check the DB for the track. If the Optional box is empty, instantly throw a 404.
+        TrackLyricsDto dto = trackRepository.findTrackAndArtistById(trackId)
+                .orElseThrow(() -> new ResponseStatusException(HttpStatus.NOT_FOUND, "Track not found in database"));
+
+        try {
+            // 2. Make the external network request using RestClient
+            ExternalLyricsResponse apiResponse = restClient.get()
+                    .uri("/{artist}/{title}", dto.getArtistName(), dto.getTrackTitle())
+                    .retrieve()
+                    .body(ExternalLyricsResponse.class);
+
+            // 3. If lyrics exist in the API payload, attach them to our response object
+            if (apiResponse != null && apiResponse.lyrics() != null) {
+                dto.setLyrics(apiResponse.lyrics());
+                return dto;
+            } else {
+                throw new ResponseStatusException(HttpStatus.NOT_FOUND, "Lyrics not found for this track in the external API");
+            }
+
+        } catch (HttpClientErrorException.NotFound e) {
+            // Catches an external 404 error and converts it into a clear, helpful message for the user
+            throw new ResponseStatusException(HttpStatus.NOT_FOUND, "The lyrics API does not have any lyrics available for this song.");
+        } catch (Exception e) {
+            throw new ResponseStatusException(HttpStatus.INTERNAL_SERVER_ERROR, "External lyrics service communication error");
+        }
+    }
+}

postify/src/main/java/net/hackyourfuture/backend/week6/postify/service/UserStatsService.java

@@ -0,0 +1,20 @@
+package net.hackyourfuture.backend.week6.postify.service;
+
+import lombok.RequiredArgsConstructor;
+import net.hackyourfuture.backend.week6.postify.dto.UserStatsDto;
+import net.hackyourfuture.backend.week6.postify.repository.UserRepository;
+import org.springframework.http.HttpStatus;
+import org.springframework.stereotype.Service;
+import org.springframework.web.server.ResponseStatusException;
+
+@Service
+@RequiredArgsConstructor
+public class UserStatsService {
+
+    private final UserRepository userRepository;
+
+    public UserStatsDto getUserStats(Integer userId) {
+        return userRepository.getUserStats(userId)
+                .orElseThrow(() -> new ResponseStatusException(HttpStatus.NOT_FOUND, "User not found"));
+    }
+}

postify/src/main/resources/application.properties

@@ -1 +1,6 @@
 spring.application.name=postify
+spring.datasource.url=jdbc:postgresql://localhost:5432/POSTIFY
+spring.datasource.username=hyfuser
+spring.datasource.password=hyfpassword
+spring.datasource.driver-class-name=org.postgresql.Driver
+logging.level.org.springframework.jdbc.core=DEBUG