| Copyright | (c) 2014-2016 Peter Trško |
|---|---|
| License | BSD3 |
| Maintainer | peter.trsko@gmail.com |
| Stability | unstable (internal module) |
| Portability | GHC specific language extensions. |
| Safe Haskell | None |
| Language | Haskell2010 |
Data.ConnectionPool.Internal.TCP
Description
Module defines type family of connection pools that is later specialised
using type tags (phantom types) to specialize implementation of underlying
ConnectionPool for various protocols.
Internal packages are here to provide access to internal definitions for library writers, but they should not be used in application code.
Preferably use qualified import, e.g.:
import qualified Data.ConnectionPool.Internal.TCP as Internal
Module introduced in version 0.2.
Synopsis
- data family ConnectionPool :: k -> *
- data TcpClient
- createTcpClientPool :: ResourcePoolParams -> ClientSettings -> IO (ConnectionPool TcpClient)
- withTcpClientConnection :: (MonadBaseControl io m, io ~ IO) => ConnectionPool TcpClient -> (AppData -> m r) -> m r
- tryWithTcpClientConnection :: (MonadBaseControl io m, io ~ IO) => ConnectionPool TcpClient -> (AppData -> m r) -> m (Maybe r)
- destroyAllTcpClientConnections :: ConnectionPool TcpClient -> IO ()
Documentation
data family ConnectionPool :: k -> * #
Family of connection pools parametrised by transport protocol.
Definition changed in version 0.2 to be kind polymorphic (only on GHC >= 7.10), and became part of stable API by being moved in to Data.ConnectionPool.Family module.
Instances
Type tag used to specialize connection pool for TCP clients.
Instance for Generic introduced in version 0.2.
Instances
createTcpClientPool :: ResourcePoolParams -> ClientSettings -> IO (ConnectionPool TcpClient) #
Create connection pool for TCP clients.
withTcpClientConnection :: (MonadBaseControl io m, io ~ IO) => ConnectionPool TcpClient -> (AppData -> m r) -> m r #
Temporarily take a TCP connection from a pool, run client with it, and
return it to the pool afterwards. For details how connections are allocated
see withResource.
tryWithTcpClientConnection :: (MonadBaseControl io m, io ~ IO) => ConnectionPool TcpClient -> (AppData -> m r) -> m (Maybe r) #
Similar to withConnection, but only performs action if a TCP connection
could be taken from the pool without blocking. Otherwise,
tryWithResource returns immediately with Nothing (ie. the action
function is not called). Conversely, if a connection can be acquired from
the pool without blocking, the action is performed and it's result is
returned, wrapped in a Just.
Since version 0.2.
destroyAllTcpClientConnections :: ConnectionPool TcpClient -> IO () #
Destroy all TCP connections that might be still open in a connection pool. This is useful when one needs to release all resources at once and not to wait for idle timeout to be reached.
For more details see destroyAllResources.
Since version 0.1.1.0.