Update controllers, services, and Flask API for production features

- Update controllers to use /api/v1/* endpoints
- Add idempotency key support in TeamController
- Update services with Redis caching and Resilience4j
- Update Flask API with Redis caching and Prometheus metrics
- Update application.properties with Redis and Flyway config
- Update .gitignore to exclude venv and build artifacts

Author: Alexander-Rees

.gitignore

@@ -27,4 +27,27 @@ yarn-error.log*
 
 # backend 
 /backend/target
+/backend/.mvn
+
+# flask-api
 flask-api/FPL-Elo-Insights/
+flask-api/__pycache__/
+flask-api/*.pyc
+flask-api/venv/
+
+# frontend
+/frontend/build
+/frontend/node_modules
+
+# Environment files
+.env
+.env.local
+
+# IDE
+*.iml
+.idea/
+.vscode/
+
+# Logs
+logs/
+*.log

backend/src/main/java/com/example/demo/controller/PlayerController.java

@@ -8,15 +8,30 @@
 import java.util.List;
 
 @RestController
-@RequestMapping("/api/players")
+@RequestMapping("/api/v1/players")
 public class PlayerController {
 
     @Autowired
     private PlayerDataService playerDataService;
 
-    // Endpoint to fetch all player data from database
+    // Endpoint to fetch player data with basic pagination and filters
     @GetMapping
-    public List<PlayerDTO> getPlayerData() {
-        return playerDataService.getAllPlayers();
+    public List<PlayerDTO> getPlayerData(
+            @RequestParam(name = "page", required = false, defaultValue = "0") int page,
+            @RequestParam(name = "size", required = false, defaultValue = "50") int size,
+            @RequestParam(name = "team", required = false) String team,
+            @RequestParam(name = "position", required = false) String position,
+            @RequestParam(name = "gw", required = false) Integer gw
+    ) {
+        List<PlayerDTO> players = playerDataService.getAllPlayers();
+        if (team != null && !team.isEmpty()) {
+            players = players.stream().filter(p -> team.equalsIgnoreCase(p.getTeam())).toList();
+        }
+        if (position != null && !position.isEmpty()) {
+            players = players.stream().filter(p -> position.equalsIgnoreCase(p.getPosition())).toList();
+        }
+        int from = Math.max(0, Math.min(page * size, players.size()));
+        int to = Math.max(0, Math.min(from + size, players.size()));
+        return players.subList(from, to);
     }
 }

backend/src/main/java/com/example/demo/controller/TeamController.java

@@ -10,15 +10,18 @@
 import com.example.demo.service.FplImportService;
 import com.example.demo.service.TeamOptimizationService;
 import com.example.demo.service.TeamService;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.redis.core.StringRedisTemplate;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
+import java.util.concurrent.TimeUnit;
 
 @RestController
-@RequestMapping("/api/team")
+@RequestMapping("/api/v1/team")
 public class TeamController {
 
     @Autowired
@@ -30,6 +33,11 @@ public class TeamController {
     @Autowired
     private TeamOptimizationService teamOptimizationService;
 
+    @Autowired(required = false)
+    private StringRedisTemplate redisTemplate;
+
+    private final ObjectMapper objectMapper = new ObjectMapper();
+
     @GetMapping
     public Team getTeam(@RequestParam Long userId) {
         return teamService.getTeamByUserId(userId);
@@ -92,11 +100,36 @@ public ResponseEntity<List<PlayerDTO>> getTeamPlayers(@RequestParam Long userId)
 
     // Team optimization endpoint
     @PostMapping("/optimize")
-    public ResponseEntity<OptimizeResponseDTO> optimizeTeam(@RequestParam Long userId, @RequestBody OptimizeRequestDTO request) {
+    public ResponseEntity<OptimizeResponseDTO> optimizeTeam(@RequestParam Long userId,
+                                                            @RequestHeader(value = "Idempotency-Key", required = false) String idempotencyKey,
+                                                            @RequestBody OptimizeRequestDTO request) {
         try {
+            // Idempotency check
+            if (idempotencyKey != null && !idempotencyKey.isEmpty() && redisTemplate != null) {
+                String cacheKey = "idempotency:" + idempotencyKey;
+                String cachedResponse = redisTemplate.opsForValue().get(cacheKey);
+                if (cachedResponse != null) {
+                    System.out.println("Idempotency key hit: " + idempotencyKey);
+                    OptimizeResponseDTO response = objectMapper.readValue(cachedResponse, OptimizeResponseDTO.class);
+                    return ResponseEntity.ok(response);
+                }
+            }
+
             System.out.println("Optimization request received for user: " + userId);
             OptimizeResponseDTO response = teamOptimizationService.optimizeTeam(userId, request);
             System.out.println("Optimization completed successfully");
+
+            // Cache response with idempotency key (5 minute TTL)
+            if (idempotencyKey != null && !idempotencyKey.isEmpty() && redisTemplate != null) {
+                try {
+                    String cacheKey = "idempotency:" + idempotencyKey;
+                    String responseJson = objectMapper.writeValueAsString(response);
+                    redisTemplate.opsForValue().set(cacheKey, responseJson, 5, TimeUnit.MINUTES);
+                } catch (Exception e) {
+                    System.err.println("Failed to cache idempotency response: " + e.getMessage());
+                }
+            }
+
             return ResponseEntity.ok(response);
         } catch (Exception e) {
             System.err.println("Optimization error: " + e.getMessage());

backend/src/main/java/com/example/demo/controller/UserController.java

@@ -11,7 +11,7 @@
 import java.util.List;
 
 @RestController
-@RequestMapping("/api/users")
+@RequestMapping("/api/v1/auth")
 public class UserController {
 
     @Autowired

backend/src/main/java/com/example/demo/dto/OptimizeRequestDTO.java

@@ -1,84 +1,44 @@
 package com.example.demo.dto;
 
+import jakarta.validation.constraints.Min;
+import jakarta.validation.constraints.NotNull;
 import java.util.List;
 
 public class OptimizeRequestDTO {
-    private Long teamId;
-    private Long entryId;
-    private Double budget;
-    private Integer freeTransfers;
-    private List<Long> lockedPlayers;
-    private List<Long> avoidPlayers;
-    private String formation;
-
-    // Constructors
-    public OptimizeRequestDTO() {}
-
-    public OptimizeRequestDTO(Long teamId, Long entryId, Double budget, Integer freeTransfers, 
-                             List<Long> lockedPlayers, List<Long> avoidPlayers, String formation) {
-        this.teamId = teamId;
-        this.entryId = entryId;
-        this.budget = budget;
-        this.freeTransfers = freeTransfers;
-        this.lockedPlayers = lockedPlayers;
-        this.avoidPlayers = avoidPlayers;
-        this.formation = formation;
-    }
+    @NotNull
+    private Long userId;
 
-    // Getters and setters
-    public Long getTeamId() {
-        return teamId;
-    }
-
-    public void setTeamId(Long teamId) {
-        this.teamId = teamId;
-    }
+    @Min(0)
+    private Double budget;
 
-    public Long getEntryId() {
-        return entryId;
-    }
+    private Integer freeTransfers;
 
-    public void setEntryId(Long entryId) {
-        this.entryId = entryId;
-    }
+    private List<Long> lockedPlayers;
 
-    public Double getBudget() {
-        return budget;
-    }
+    private List<Long> avoidPlayers;
 
-    public void setBudget(Double budget) {
-        this.budget = budget;
-    }
+    private String formation;
 
-    public Integer getFreeTransfers() {
-        return freeTransfers;
-    }
+    private Integer gw;
 
-    public void setFreeTransfers(Integer freeTransfers) {
-        this.freeTransfers = freeTransfers;
-    }
+    public Long getUserId() { return userId; }
+    public void setUserId(Long userId) { this.userId = userId; }
 
-    public List<Long> getLockedPlayers() {
-        return lockedPlayers;
-    }
+    public Double getBudget() { return budget; }
+    public void setBudget(Double budget) { this.budget = budget; }
 
-    public void setLockedPlayers(List<Long> lockedPlayers) {
-        this.lockedPlayers = lockedPlayers;
-    }
+    public Integer getFreeTransfers() { return freeTransfers; }
+    public void setFreeTransfers(Integer freeTransfers) { this.freeTransfers = freeTransfers; }
 
-    public List<Long> getAvoidPlayers() {
-        return avoidPlayers;
-    }
+    public List<Long> getLockedPlayers() { return lockedPlayers; }
+    public void setLockedPlayers(List<Long> lockedPlayers) { this.lockedPlayers = lockedPlayers; }
 
-    public void setAvoidPlayers(List<Long> avoidPlayers) {
-        this.avoidPlayers = avoidPlayers;
-    }
+    public List<Long> getAvoidPlayers() { return avoidPlayers; }
+    public void setAvoidPlayers(List<Long> avoidPlayers) { this.avoidPlayers = avoidPlayers; }
 
-    public String getFormation() {
-        return formation;
-    }
+    public String getFormation() { return formation; }
+    public void setFormation(String formation) { this.formation = formation; }
 
-    public void setFormation(String formation) {
-        this.formation = formation;
-    }
+    public Integer getGw() { return gw; }
+    public void setGw(Integer gw) { this.gw = gw; }
 }

backend/src/main/java/com/example/demo/service/PlayerDataService.java

@@ -3,6 +3,7 @@
 import com.example.demo.dto.PlayerDTO;
 import com.example.demo.model.Player;
 import com.example.demo.repository.PlayerRepository;
+import org.springframework.cache.annotation.Cacheable;
 import org.springframework.stereotype.Service;
 
 import java.util.List;
@@ -17,7 +18,8 @@ public PlayerDataService(PlayerRepository playerRepository) {
         this.playerRepository = playerRepository;
     }
 
-    // Get all players from database
+    // Get all players from database - cached
+    @Cacheable(value = "players", key = "'all'")
     public List<PlayerDTO> getAllPlayers() {
         List<Player> players = playerRepository.findAll();
         return players.stream()

backend/src/main/java/com/example/demo/service/TeamOptimizationService.java

@@ -6,14 +6,21 @@
 import com.example.demo.model.User;
 import com.example.demo.repository.PlayerRepository;
 import com.example.demo.repository.TeamRepository;
+import io.github.resilience4j.circuitbreaker.annotation.CircuitBreaker;
+import io.github.resilience4j.retry.annotation.Retry;
+import io.github.resilience4j.bulkhead.annotation.Bulkhead;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.http.*;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.RestTemplate;
 import org.springframework.http.client.SimpleClientHttpRequestFactory;
+import org.springframework.data.redis.core.RedisTemplate;
+import org.springframework.data.redis.core.StringRedisTemplate;
 
 import java.util.*;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 
 @Service
@@ -28,6 +35,9 @@ public class TeamOptimizationService {
     @Autowired
     private PlayerDataService playerDataService;
 
+    @Autowired(required = false)
+    private StringRedisTemplate redisTemplate;
+
     @Value("${flask.api.url:http://localhost:5001}")
     private String flaskApiUrl;
 
@@ -82,22 +92,9 @@ public OptimizeResponseDTO optimizeTeam(Long userId, OptimizeRequestDTO request)
 
             System.out.println("Calling Flask API at: " + flaskApiUrl + "/_ml/optimize");
 
-            // Call Flask ML API
-            HttpHeaders headers = new HttpHeaders();
-            headers.setContentType(MediaType.APPLICATION_JSON);
-            HttpEntity<Map<String, Object>> entity = new HttpEntity<>(flaskRequest, headers);
-
-            String optimizeUrl = flaskApiUrl + "/_ml/optimize";
-            ResponseEntity<Map> response = restTemplate.postForEntity(optimizeUrl, entity, Map.class);
-
-            System.out.println("Flask API response status: " + response.getStatusCode());
-            System.out.println("Flask API response body: " + response.getBody());
-
-            if (response.getStatusCode().is2xxSuccessful() && response.getBody() != null) {
-                return parseFlaskResponse(response.getBody());
-            } else {
-                throw new RuntimeException("Flask API returned error: " + response.getStatusCode());
-            }
+            // Call Flask ML API with resilience patterns
+            Map<String, Object> flaskResponse = callFlaskOptimization(flaskRequest);
+            return parseFlaskResponse(flaskResponse);
 
         } catch (Exception e) {
             System.out.println("Flask API call failed, using fallback: " + e.getMessage());
@@ -107,6 +104,36 @@ public OptimizeResponseDTO optimizeTeam(Long userId, OptimizeRequestDTO request)
         }
     }
 
+    @CircuitBreaker(name = "flaskMl", fallbackMethod = "flaskFallback")
+    @Retry(name = "flaskMl")
+    @Bulkhead(name = "flaskMl")
+    private Map<String, Object> callFlaskOptimization(Map<String, Object> flaskRequest) {
+        HttpHeaders headers = new HttpHeaders();
+        headers.setContentType(MediaType.APPLICATION_JSON);
+        // Service-to-service auth header
+        String internalToken = System.getProperty("INTERNAL_API_TOKEN",
+                System.getenv().getOrDefault("INTERNAL_API_TOKEN", "dev-internal-token"));
+        headers.add("X-Internal-Token", internalToken);
+        HttpEntity<Map<String, Object>> entity = new HttpEntity<>(flaskRequest, headers);
+
+        String optimizeUrl = flaskApiUrl + "/_ml/optimize";
+        ResponseEntity<Map> response = restTemplate.postForEntity(optimizeUrl, entity, Map.class);
+
+        System.out.println("Flask API response status: " + response.getStatusCode());
+        System.out.println("Flask API response body: " + response.getBody());
+
+        if (response.getStatusCode().is2xxSuccessful() && response.getBody() != null) {
+            return response.getBody();
+        } else {
+            throw new RuntimeException("Flask API returned error: " + response.getStatusCode());
+        }
+    }
+
+    private Map<String, Object> flaskFallback(Map<String, Object> flaskRequest, Exception e) {
+        System.out.println("Circuit breaker fallback triggered: " + e.getMessage());
+        throw new RuntimeException("Flask service unavailable", e);
+    }
+
     private OptimizeResponseDTO parseFlaskResponse(Map<String, Object> response) {
         System.out.println("Parsing Flask response: " + response);