Fix ClientID

mqtt_presence_redis_go/mqtt_presence_redis_go.go

@@ -7,7 +7,8 @@ import (
     "os"
     "strings"
     "time"
-    "crypto/rand"
+    "strconv"
+    "math/rand"
 
     mqtt "github.com/eclipse/paho.mqtt.golang"
     "github.com/go-redis/redis/v8"
@@ -39,7 +40,7 @@ func main() {
     rdb := redis.NewClient(&redis.Options{
         Addr:     fmt.Sprintf("%s:%s", redisHost, redisPort),
         Password: redisPassword,
-        DB:       atoi(redisDB),
+        DB:       parseInt(redisDB),
     })
 
     // Ping to verify connection
@@ -102,7 +103,7 @@ func handleMessage(ctx context.Context, rdb *redis.Client, msg mqtt.Message) {
         return
     }
 
-    if err := rdb.SetEX(ctx, key, data, time.Duration(atoi(redisSetEX))*time.Second).Err(); err != nil {
+    if err := rdb.SetEX(ctx, key, data, time.Duration(parseInt(redisSetEX))*time.Second).Err(); err != nil {
         log.Printf("Failed to set Redis key: %v", err)
     }
 }
@@ -114,11 +115,20 @@ func getEnv(key, defaultVal string) string {
     return defaultVal
 }
 
+func parseInt(s string) int {
+    i, err := strconv.Atoi(s)
+    if err != nil {
+        log.Printf("Failed to parse int from %s: %v", s, err)
+        return 0
+    }
+    return i
+}
+
 func randomString() string {
-    b := make([]byte, 4)
-    if _, err := rand.Read(b); err != nil {
-        log.Printf("Failed to generate random string: %v", err)
-        return ""
+    const letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+    b := make([]byte, 10)
+    for i := range b {
+        b[i] = letters[rand.Intn(len(letters))]
     }
-    return hex.EncodeToString(b)
+    return string(b)
 }