Snap.Snaplet.RedisDB

Redis DB snaplet.

Documentation

newtype RedisDB

Snaplet's state data type

Constructors

RedisDB

Fields

• _connection :: Connection

  DB connection pool.

runRedisDB :: (MonadIO m, MonadState app m) => Lens' app (Snaplet RedisDB) -> Redis a -> m a

Perform action using Redis connection from RedisDB snaplet pool (wrapper for runRedis).

runRedisDB database $ do
  set "hello" "world"

redisConnection :: Lens' RedisDB Connection

A lens to retrieve the connection to Redis from the RedisDB wrapper.

redisDBInit

Arguments

:: ConnectInfo

Information for connnecting to a Redis server.

-> SnapletInit b RedisDB

Make RedisDB snaplet and initialize database connection.

appInit :: SnapletInit MyApp MyApp
appInit = makeSnaplet "app" "App with Redis child snaplet" Nothing $
          do
            d <- nestSnaplet "" database $
                                redisDBInit defaultConnectInfo
            return $ MyApp d

redisDBInitConf :: SnapletInit b RedisDB

Make RedisDB snaplet and initialize database connection from snaplet config file. Options are read from the "redis" section of the application config (e.g. ./devel.cfg) or from the main section of the Redis snaplet config (e.g. .snapletsredis/devel.cfg).

Every field is optional and defaults to defaultConnectInfo values.

redis {
    host = "192.168.0.42"
    port = 31415
    auth = "i am so secret"
    max_connections = 1
    max_idle_time = 0.5
}

Alternately, you can configure it to connect via a socket, for example:

redis {
    port = "/var/run/redis/redis.sock"
}

This corresponds to setting:

connectPort = UnixSocket "/var/run/redis/redis.sock"

in ConnectInfo. In this case, the host setting, if anything, is ignored.

appInit :: SnapletInit MyApp MyApp
appInit = makeSnaplet "app" "App with Redis child snaplet" Nothing $
          do
            d <- nestSnaplet "redis" database redisDBInitConf
            return $ MyApp d