SETEX error - "Use of closed network connection" - go

Question

I'm using the following code to execute a SET and EXPIRE from my Go app.
_, err = C.Cache.Do("SETEX", key, 3600, data)
but I've started to get an error: Use of closed network connection. I use Gary Burd's Redigo package and RedisLabs.
My code to connect to Redis is:
//Connect to cache (Redis)
cache, err := connectToCache()
if err != nil {
log.Printf("Cache connection settings are invalid")
os.Exit(1)
}
defer cache.Close()
func connectToCache() (redis.Conn, error) {
cache, err := redis.Dial("tcp", CACHE_URI)
if err != nil {
return nil, err
}
_, err = cache.Do("AUTH", CACHE_AUTH)
if err != nil {
cache.Close()
return nil, err
}
return cache, nil
}

Answer 1

You can use a redis.Pool to manage multiple connections, check that idle connections are alive, and get new connections automatically. You can also do the AUTH step automatically when dialing a new connection:
func newPool(server, password string) *redis.Pool {
return &redis.Pool{
MaxIdle: 3,
IdleTimeout: 240 * time.Second,
Dial: func () (redis.Conn, error) {
c, err := redis.Dial("tcp", server)
if err != nil {
return nil, err
}
if _, err := c.Do("AUTH", password); err != nil {
c.Close()
return nil, err
}
return c, err
},
TestOnBorrow: func(c redis.Conn, t time.Time) error {
_, err := c.Do("PING")
return err
},
}
}
var (
pool *redis.Pool
redisServer = flag.String("redisServer", ":6379", "")
redisPassword = flag.String("redisPassword", "", "")
)
func main() {
flag.Parse()
pool = newPool(*redisServer, *redisPassword)
...
}