// Dial dials the local Redis server and selects database 9. To prevent
// stomping on real data, DialTestDB fails if database 9 contains data. The
// returned connection flushes database 9 on close.
func Dial() (redis.Conn, error) {
c, err := redis.DialTimeout("tcp", ":6379", 0, 1*time.Second, 1*time.Second)
if err != nil {
return nil, err
}
_, err = c.Do("SELECT", "9")
if err != nil {
c.Close()
return nil, err
}
n, err := redis.Int(c.Do("DBSIZE"))
if err != nil {
c.Close()
return nil, err
}
if n != 0 {
c.Close()
return nil, errors.New("database #9 is not empty, test can not continue")
}
return testConn{c}, nil
}
func (app *App) configureRedis(configuration *configuration.Configuration) {
if configuration.Redis.Addr == "" {
ctxu.GetLogger(app).Infof("redis not configured")
return
}
pool := &redis.Pool{
Dial: func() (redis.Conn, error) {
// TODO(stevvooe): Yet another use case for contextual timing.
ctx := context.WithValue(app, "redis.connect.startedat", time.Now())
done := func(err error) {
logger := ctxu.GetLoggerWithField(ctx, "redis.connect.duration",
ctxu.Since(ctx, "redis.connect.startedat"))
if err != nil {
logger.Errorf("redis: error connecting: %v", err)
} else {
logger.Infof("redis: connect %v", configuration.Redis.Addr)
}
}
conn, err := redis.DialTimeout("tcp",
configuration.Redis.Addr,
configuration.Redis.DialTimeout,
configuration.Redis.ReadTimeout,
configuration.Redis.WriteTimeout)
if err != nil {
ctxu.GetLogger(app).Errorf("error connecting to redis instance %s: %v",
configuration.Redis.Addr, err)
done(err)
return nil, err
}
// authorize the connection
if configuration.Redis.Password != "" {
if _, err = conn.Do("AUTH", configuration.Redis.Password); err != nil {
defer conn.Close()
done(err)
return nil, err
}
}
// select the database to use
if configuration.Redis.DB != 0 {
if _, err = conn.Do("SELECT", configuration.Redis.DB); err != nil {
defer conn.Close()
done(err)
return nil, err
}
}
done(nil)
return conn, nil
},
MaxIdle: configuration.Redis.Pool.MaxIdle,
MaxActive: configuration.Redis.Pool.MaxActive,
IdleTimeout: configuration.Redis.Pool.IdleTimeout,
TestOnBorrow: func(c redis.Conn, t time.Time) error {
// TODO(stevvooe): We can probably do something more interesting
// here with the health package.
_, err := c.Do("PING")
return err
},
Wait: false, // if a connection is not avialable, proceed without cache.
}
app.redis = pool
// setup expvar
registry := expvar.Get("registry")
if registry == nil {
registry = expvar.NewMap("registry")
}
registry.(*expvar.Map).Set("redis", expvar.Func(func() interface{} {
return map[string]interface{}{
"Config": configuration.Redis,
"Active": app.redis.ActiveCount(),
}
}))
}