content: {-# LANGUAGE TupleSections, TemplateHaskell #-}
  {-| Configuration server for the metadata daemon.
  
  -}
  
  {-
  
  Copyright (C) 2014 Google Inc.
  All rights reserved.
  
  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions are
  met:
  
  1. Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
  
  2. Redistributions in binary form must reproduce the above copyright
  notice, this list of conditions and the following disclaimer in the
  documentation and/or other materials provided with the distribution.
  
  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  -}
  module Ganeti.Metad.ConfigServer where
  
  import Control.Exception (finally)
  import Control.Monad (forever)
  
  import Ganeti.Path as Path
  import Ganeti.Daemon (DaemonOptions, cleanupSocket, describeError)
  import Ganeti.Runtime (GanetiDaemon(..), GanetiGroup(..), MiscGroup(..))
  import Ganeti.THH.RPC
  import Ganeti.UDSServer (ConnectConfig(..), ServerConfig(..))
  import qualified Ganeti.UDSServer as UDSServer
  import Ganeti.Utils (FilePermissions(..))
  
  import Ganeti.Metad.ConfigCore
  
  -- * The handler that converts RPCs to calls to the above functions
  
  handler :: RpcServer MetadMonadInt
  handler = $( mkRpcM exportedFunctions )
  
  -- * The main server code
  
  start :: DaemonOptions -> MetadHandle -> IO ()
  start _ config = do
       socket_path <- Path.defaultMetadSocket
       cleanupSocket socket_path
       server <- describeError "binding to the socket" Nothing (Just socket_path)
                 $ UDSServer.connectServer metadConfig True socket_path
       finally
         (forever $ runMetadMonadInt (UDSServer.listener handler server) config)
         (UDSServer.closeServer server)
    where
      metadConfig =
        ServerConfig
          -- The permission 0600 is completely acceptable because only the node
          -- daemon talks to the metadata daemon, and the node daemon runs as
          -- root.
          FilePermissions { fpOwner = Just GanetiMetad
                          , fpGroup = Just $ ExtraGroup DaemonsGroup
                          , fpPermissions = 0o0600
                          }
          ConnectConfig { recvTmo = 60
                        , sendTmo = 60
                        }
  