Fix: Refactor Redis error handling and improve key deletion logic

Removed redundant error checks and imports. Enhanced the key deletion logic by checking the result of deletion operations and only appending keys that were actually deleted. This refactoring simplifies the code and improves readability.

Signed-off-by: Christian Roessner <[email protected]>

server/core/register.go

@@ -16,7 +16,6 @@
 package core
 
 import (
-	stderrors "errors"
 	"fmt"
 	"net/http"
 
@@ -34,7 +33,6 @@ import (
 	"github.com/go-kit/log/level"
 	"github.com/pquerna/otp"
 	"github.com/pquerna/otp/totp"
-	"github.com/redis/go-redis/v9"
 	"github.com/spf13/viper"
 	"golang.org/x/text/cases"
 	"golang.org/x/text/language"
@@ -793,11 +791,6 @@ func registerTotpPOSTHandler(ctx *gin.Context) {
 			if _, err = rediscli.WriteHandle.Del(ctx, userKey).Result(); err != nil {
 				stats.RedisWriteCounter.Inc()
 
-				if stderrors.Is(err, redis.Nil) {
-
-					continue
-				}
-
 				level.Error(log.Logger).Log(global.LogKeyGUID, guid, global.LogKeyMsg, err)
 
 				break

server/core/rest.go

@@ -467,6 +467,7 @@ func processFlushCache(ctx *gin.Context, userCmd *FlushUserCmd, guid string) (re
 // 5. Returns false.
 func processUserCmd(ctx *gin.Context, userCmd *FlushUserCmd, guid string) (removedKeys []string, noUserAccountFound bool) {
 	var (
+		result        int64
 		removeHash    bool
 		accountName   string
 		ipAddresses   []string
@@ -499,28 +500,24 @@ func processUserCmd(ctx *gin.Context, userCmd *FlushUserCmd, guid string) (remov
 
 	// Remove PW_HIST_SET from Redis
 	key := getPWHistIPsRedisKey(accountName)
-	if err = rediscli.WriteHandle.Del(ctx, key).Err(); err != nil {
-		if !stderrors.Is(err, redis.Nil) {
-			level.Error(log.Logger).Log(global.LogKeyGUID, guid, global.LogKeyMsg, err)
-		} else {
-			err = nil
-		}
+	if result, err = rediscli.WriteHandle.Del(ctx, key).Result(); err != nil {
+		level.Error(log.Logger).Log(global.LogKeyGUID, guid, global.LogKeyMsg, err)
 	} else {
-		removedKeys = append(removedKeys, key)
+		if result > 0 {
+			removedKeys = append(removedKeys, key)
+		}
 	}
 
 	defer stats.RedisWriteCounter.Inc()
 
-	// Remove account from BLOCKED_ACCOUNTS
+	// Remove an account from AFFECTED_ACCOUNTS
 	key = config.LoadableConfig.Server.Redis.Prefix + global.RedisAffectedAccountsKey
-	if err = rediscli.WriteHandle.SRem(ctx, key, accountName).Err(); err != nil {
-		if !stderrors.Is(err, redis.Nil) {
-			level.Error(log.Logger).Log(global.LogKeyGUID, guid, global.LogKeyMsg, err)
-		} else {
-			err = nil
-		}
+	if result, err = rediscli.WriteHandle.SRem(ctx, key, accountName).Result(); err != nil {
+		level.Error(log.Logger).Log(global.LogKeyGUID, guid, global.LogKeyMsg, err)
 	} else {
-		removedKeys = append(removedKeys, key)
+		if result > 0 {
+			removedKeys = append(removedKeys, key)
+		}
 	}
 
 	removedKeys = append(removedKeys, removeUserFromCache(ctx, userCmd, userKeys, guid, removeHash)...)
@@ -591,7 +588,10 @@ func prepareRedisUserKeys(ctx context.Context, guid string, accountName string)
 // If any error occurs during the removal process, it logs the error and immediately returns.
 // After successful removal, it logs the keys that have been flushed.
 func removeUserFromCache(ctx context.Context, userCmd *FlushUserCmd, userKeys config.StringSet, guid string, removeHash bool) []string {
-	var err error
+	var (
+		result int64
+		err    error
+	)
 
 	removedKeys := make([]string, 0)
 
@@ -612,21 +612,15 @@ func removeUserFromCache(ctx context.Context, userCmd *FlushUserCmd, userKeys co
 	}
 
 	for _, userKey := range userKeys.GetStringSlice() {
-		if err = rediscli.WriteHandle.Del(ctx, userKey).Err(); err != nil {
-			if !stderrors.Is(err, redis.Nil) {
-				stats.RedisWriteCounter.Inc()
-
-				level.Error(log.Logger).Log(global.LogKeyGUID, guid, global.LogKeyMsg, err)
+		if result, err = rediscli.WriteHandle.Del(ctx, userKey).Result(); err != nil {
+			level.Error(log.Logger).Log(global.LogKeyGUID, guid, global.LogKeyMsg, err)
 
-				return removedKeys
-			}
+			return removedKeys
 		}
 
 		stats.RedisWriteCounter.Inc()
 
-		if err != nil {
-			level.Warn(log.Logger).Log(global.LogKeyGUID, guid, "keys", userKey, "status", "not found")
-		} else {
+		if result > 0 {
 			removedKeys = append(removedKeys, userKey)
 
 			level.Info(log.Logger).Log(global.LogKeyGUID, guid, "keys", userKey, "status", "flushed")