#32 Add cron for cleanup of keys from DiceDB (#43)

.env.sample

@@ -1,8 +1,12 @@
-DICEDB_ADDR=localhost:7379
+DICEDB_ADMIN_ADDR=localhost:7379
+DICEDB_ADMIN_USERNAME=diceadmin
+DICEDB_ADMIN_PASSWORD=
+DICEDB_ADDR=localhost:7380
 DICEDB_USERNAME=dice
 DICEDB_PASSWORD=
 SERVER_PORT=:8080
 IS_TEST_ENVIRONMENT=false
 REQUEST_LIMIT_PER_MIN=1000
 REQUEST_WINDOW_SEC=60
-ALLOWED_ORIGINS=http://localhost:3000
+ALLOWED_ORIGINS=http://localhost:3000
+CRON_CLEANUP_FREQUENCY_MINS=15

config/config.go

@@ -1,59 +1,81 @@
 package config
 
 import (
-	"fmt"
+	"log/slog"
 	"os"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/joho/godotenv"
 )
 
 // Config holds the application configuration
 type Config struct {
+	// Config for DiceDBAdmin instance. This instance holds internal keys
+	// and is separate from DiceDB hosting global key pool i.e. user facing.
+	DiceDBAdmin struct {
+		Addr     string // Field for the Dice address
+		Username string // Field for the username
+		Password string // Field for the password
+	}
+	// Config for DiceDB User instance. This instance holds internal keys
+	// and is separate from DiceDB hosting global key pool i.e. user facing.
 	DiceDB struct {
 		Addr     string // Field for the Dice address
 		Username string // Field for the username
 		Password string // Field for the password
 	}
 	Server struct {
-		Port               string // Field for the server port
-		IsTestEnv          bool
-		RequestLimitPerMin int64    // Field for the request limit
-		RequestWindowSec   float64  // Field for the time window in float64
-		AllowedOrigins     []string // Field for the allowed origins
+		Port                 string // Field for the server port
+		IsTestEnv            bool
+		RequestLimitPerMin   int64         // Field for the request limit
+		RequestWindowSec     float64       // Field for the time window in float64
+		AllowedOrigins       []string      // Field for the allowed origins
+		CronCleanupFrequency time.Duration // Field for configuring key cleanup cron
 	}
 }
 
 // LoadConfig loads the application configuration from environment variables or defaults
 func LoadConfig() *Config {
 	err := godotenv.Load()
 	if err != nil {
-		fmt.Println("Warning: .env file not found, falling back to system environment variables.")
+		slog.Debug("Warning: .env file not found, falling back to system environment variables.")
 	}
 
 	return &Config{
+		DiceDBAdmin: struct {
+			Addr     string
+			Username string
+			Password string
+		}{
+			Addr:     getEnv("DICEDB_ADMIN_ADDR", "localhost:7379"), // Default DiceDB Admin address
+			Username: getEnv("DICEDB_ADMIN_USERNAME", "diceadmin"),  // Default DiceDB Admin username
+			Password: getEnv("DICEDB_ADMIN_PASSWORD", ""),           // Default DiceDB Admin password
+		},
 		DiceDB: struct {
 			Addr     string
 			Username string
 			Password string
 		}{
-			Addr:     getEnv("DICEDB_ADDR", "localhost:7379"), // Default Dice address
+			Addr:     getEnv("DICEDB_ADDR", "localhost:7380"), // Default DiceDB address
 			Username: getEnv("DICEDB_USERNAME", "dice"),       // Default username
 			Password: getEnv("DICEDB_PASSWORD", ""),           // Default password
 		},
 		Server: struct {
-			Port               string
-			IsTestEnv          bool
-			RequestLimitPerMin int64
-			RequestWindowSec   float64
-			AllowedOrigins     []string
+			Port                 string
+			IsTestEnv            bool
+			RequestLimitPerMin   int64
+			RequestWindowSec     float64
+			AllowedOrigins       []string
+			CronCleanupFrequency time.Duration
 		}{
-			Port:               getEnv("SERVER_PORT", ":8080"),
-			IsTestEnv:          getEnvBool("IS_TEST_ENVIRONMENT", false),                          // Default server port
-			RequestLimitPerMin: getEnvInt("REQUEST_LIMIT_PER_MIN", 1000),                          // Default request limit
-			RequestWindowSec:   getEnvFloat64("REQUEST_WINDOW_SEC", 60),                           // Default request window in float64
-			AllowedOrigins:     getEnvArray("ALLOWED_ORIGINS", []string{"http://localhost:3000"}), // Default allowed origins
+			Port:                 getEnv("SERVER_PORT", ":8080"),
+			IsTestEnv:            getEnvBool("IS_TEST_ENVIRONMENT", false),                                  // Default server port
+			RequestLimitPerMin:   getEnvInt("REQUEST_LIMIT_PER_MIN", 1000),                                  // Default request limit
+			RequestWindowSec:     getEnvFloat64("REQUEST_WINDOW_SEC", 60),                                   // Default request window in float64
+			AllowedOrigins:       getEnvArray("ALLOWED_ORIGINS", []string{"http://localhost:3000"}),         // Default allowed origins
+			CronCleanupFrequency: time.Duration(getEnvInt("CRON_CLEANUP_FREQUENCY_MINS", 15)) * time.Minute, // Default cron cleanup frequency
 		},
 	}
 }

docker-compose.yml

@@ -1,5 +1,5 @@
 services:
-  dicedb:
+  dicedbadmin:
     image: dicedb/dicedb:latest
     ports:
       - "7379:7379"
@@ -11,15 +11,31 @@ services:
     networks:
      - dice-network
 
+  dicedb:
+    image: dicedb/dicedb:latest
+    ports:
+      - "7380:7379"
+    healthcheck:
+      test: [ "CMD", "PING" ]
+      interval: 10s
+      timeout: 3s
+      retries: 3
+    networks:
+      - dice-network
+
   backend:
     build:
       context: .
     ports:
       - "8080:8080"
     depends_on:
+      - dicedbadmin
       - dicedb
     environment:
-      - DICEDB_ADDR=localhost:7379
+      - DICEDB_ADMIN_ADDR=localhost:7379
+      - DICEDB_ADMIN_USERNAME=${DICEDB_ADMIN_USERNAME}
+      - DICEDB_ADMIN_PASSWORD=${DICEDB_ADMIN_PASSWORD}
+      - DICEDB_ADDR=localhost:7380
       - DICEDB_USERNAME=${DICEDB_USERNAME}
       - DICEDB_PASSWORD=${DICEDB_PASSWORD}
     networks:

internal/db/dicedb.go

@@ -33,15 +33,27 @@ func (db *DiceDB) CloseDiceDB() {
 	}
 }
 
-func InitDiceClient(configValue *config.Config) (*DiceDB, error) {
-	diceClient := dicedb.NewClient(&dicedb.Options{
-		Addr:                 configValue.DiceDB.Addr,
-		Username:             configValue.DiceDB.Username,
-		Password:             configValue.DiceDB.Password,
-		DialTimeout:          10 * time.Second,
-		MaxRetries:           10,
-		EnablePrettyResponse: true,
-	})
+func InitDiceClient(configValue *config.Config, isAdmin bool) (*DiceDB, error) {
+	var diceClient *dicedb.Client
+	if isAdmin {
+		diceClient = dicedb.NewClient(&dicedb.Options{
+			Addr:                 configValue.DiceDBAdmin.Addr,
+			Username:             configValue.DiceDBAdmin.Username,
+			Password:             configValue.DiceDBAdmin.Password,
+			DialTimeout:          10 * time.Second,
+			MaxRetries:           10,
+			EnablePrettyResponse: true,
+		})
+	} else {
+		diceClient = dicedb.NewClient(&dicedb.Options{
+			Addr:                 configValue.DiceDB.Addr,
+			Username:             configValue.DiceDB.Username,
+			Password:             configValue.DiceDB.Password,
+			DialTimeout:          10 * time.Second,
+			MaxRetries:           10,
+			EnablePrettyResponse: true,
+		})
+	}
 
 	// Ping the dicedb client to verify the connection
 	err := diceClient.Ping(context.Background()).Err()

internal/middleware/ratelimiter.go

@@ -7,6 +7,7 @@ import (
 	"log/slog"
 	"net/http"
 	"server/internal/db"
+	"server/internal/server/utils"
 	mock "server/internal/tests/dbmocks"
 	"strconv"
 	"strings"
@@ -58,7 +59,7 @@ func RateLimiter(client *db.DiceDB, next http.Handler, limit int64, window float
 		// Check if the request count exceeds the limit
 		if requestCount >= limit {
 			slog.Warn("Request limit exceeded", "count", requestCount)
-			addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window))
+			addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window), 0)
 			http.Error(w, "429 - Too Many Requests", http.StatusTooManyRequests)
 			return
 		}
@@ -77,7 +78,22 @@ func RateLimiter(client *db.DiceDB, next http.Handler, limit int64, window float
 			}
 		}
 
-		addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window))
+		// Get the cron last cleanup run time
+		var lastCronCleanupTime int64
+		resp := client.Client.Get(ctx, utils.LastCronCleanupTimeUnixMs)
+		if resp.Err() != nil && !errors.Is(resp.Err(), dicedb.Nil) {
+			slog.Error("Failed to get last cron cleanup time for headers", slog.Any("err", resp.Err().Error()))
+		}
+
+		if resp.Val() != "" {
+			lastCronCleanupTime, err = strconv.ParseInt(resp.Val(), 10, 64)
+			if err != nil {
+				slog.Error("Error converting last cron cleanup time", "error", err)
+			}
+		}
+
+		addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window),
+			lastCronCleanupTime)
 
 		slog.Info("Request processed", "count", requestCount+1)
 		next.ServeHTTP(w, r)
@@ -126,7 +142,7 @@ func MockRateLimiter(client *mock.DiceDBMock, next http.Handler, limit int64, wi
 		// Check if the request limit has been exceeded
 		if requestCount >= limit {
 			slog.Warn("Request limit exceeded", "count", requestCount)
-			addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window))
+			addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window), 0)
 			http.Error(w, "429 - Too Many Requests", http.StatusTooManyRequests)
 			return
 		}
@@ -147,19 +163,21 @@ func MockRateLimiter(client *mock.DiceDBMock, next http.Handler, limit int64, wi
 			}
 		}
 
-		addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window))
+		addRateLimitHeaders(w, limit, limit-(requestCount+1), requestCount+1, currentWindow+int64(window), 0)
 
 		slog.Info("Request processed", "count", requestCount)
 		next.ServeHTTP(w, r)
 	})
 }
 
-func addRateLimitHeaders(w http.ResponseWriter, limit, remaining, used, resetTime int64) {
+func addRateLimitHeaders(w http.ResponseWriter, limit, remaining, used, resetTime, cronLastCleanupTime int64) {
 	w.Header().Set("x-ratelimit-limit", strconv.FormatInt(limit, 10))
 	w.Header().Set("x-ratelimit-remaining", strconv.FormatInt(remaining, 10))
 	w.Header().Set("x-ratelimit-used", strconv.FormatInt(used, 10))
 	w.Header().Set("x-ratelimit-reset", strconv.FormatInt(resetTime, 10))
+	w.Header().Set("x-last-cleanup-time", strconv.FormatInt(cronLastCleanupTime, 10))
 
 	// Expose the rate limit headers to the client
-	w.Header().Set("Access-Control-Expose-Headers", "x-ratelimit-limit, x-ratelimit-remaining, x-ratelimit-used, x-ratelimit-reset")
+	w.Header().Set("Access-Control-Expose-Headers", "x-ratelimit-limit, x-ratelimit-remaining,"+
+		"x-ratelimit-used, x-ratelimit-reset, x-last-cleanup-time")
 }

internal/server/cleanup_manager.go

@@ -0,0 +1,83 @@
+package server
+
+import (
+	"context"
+	"errors"
+	"log/slog"
+	"server/internal/db"
+	"server/internal/server/utils"
+	"strconv"
+	"sync"
+	"time"
+
+	"github.com/dicedb/dicedb-go"
+)
+
+type CleanupManager struct {
+	diceDBAdminClient *db.DiceDB
+	diceDBClient      *db.DiceDB
+	cronFrequency     time.Duration
+}
+
+func NewCleanupManager(diceDBAdminClient *db.DiceDB,
+	diceDBClient *db.DiceDB, cronFrequency time.Duration) *CleanupManager {
+	return &CleanupManager{
+		diceDBAdminClient: diceDBAdminClient,
+		diceDBClient:      diceDBClient,
+		cronFrequency:     cronFrequency,
+	}
+}
+
+func (c *CleanupManager) Run(ctx context.Context, wg *sync.WaitGroup) {
+	defer wg.Done()
+	c.start(ctx)
+}
+
+func (c *CleanupManager) start(ctx context.Context) {
+	ticker := time.NewTicker(c.cronFrequency)
+	defer ticker.Stop()
+
+	// Get the last cron run time
+	resp := c.diceDBAdminClient.Client.Get(ctx, utils.LastCronCleanupTimeUnixMs)
+	if resp.Err() != nil {
+		if errors.Is(resp.Err(), dicedb.Nil) {
+			// Default to current time
+			cleanupTime := strconv.FormatInt(time.Now().UnixMilli(), 10)
+			slog.Debug("Defaulting last cron cleanup time key since not set", slog.Any("cleanupTime", cleanupTime))
+			resp := c.diceDBAdminClient.Client.Set(ctx, utils.LastCronCleanupTimeUnixMs, cleanupTime, -1)
+			if resp.Err() != nil {
+				slog.Error("Failed to set default value for last cron cleanup time key",
+					slog.Any("err", resp.Err().Error()))
+			}
+		} else {
+			slog.Error("Failed to get last cron cleanup time", slog.Any("err", resp.Err().Error()))
+		}
+	}
+
+	for {
+		select {
+		case <-ticker.C:
+			c.runCronTasks()
+		case <-ctx.Done():
+			slog.Info("Shutting down cleanup manager")
+			return
+		}
+	}
+}
+
+func (c *CleanupManager) runCronTasks() {
+	// Flush the user DiceDB instance
+	resp := c.diceDBClient.Client.FlushDB(c.diceDBClient.Ctx)
+	if resp.Err() != nil {
+		slog.Error("Failed to flush keys from DiceDB user instance.")
+	}
+
+	// Update last cron run time on DiceDB instance
+	cleanupTime := strconv.FormatInt(time.Now().UnixMilli(), 10)
+	resp = c.diceDBAdminClient.Client.Set(c.diceDBClient.Ctx, utils.LastCronCleanupTimeUnixMs,
+		cleanupTime, -1)
+	slog.Debug("Updating last cron cleanup time key", slog.Any("cleanupTime", cleanupTime))
+	if resp.Err() != nil {
+		slog.Error("Failed to set LastCronCleanupTimeUnixMs")
+	}
+}