On Wed, Apr 2, 2014 at 9:34 AM, Jose A. Lopes <[email protected]> wrote:
> The configuration server listens on a Unix socket for connections from > the node daemon. The node daemon sends the instance parameters to the > configuration server so they can be served through the metadata daemon > web server to the instances which have the communication mechanism > enabled. > > The configuration server reads the instance parameters and, currently, > it extracts the instance's name and the instance's IP address on the > instance communication NIC. The instance's name is used for logging > and the IP address is used to index the instance parameters, given > that instances do not authenticate with the metadata daemon, and the > only thing we know about them is their IP address. > > The configuration server also extracts the OS parameters, including > public, private and secret, and creates an object containing those > parameters and their visibility. > > The configuration is kept internally in an 'MVar' which will be shared > with the metadata daemon web server. > > Signed-off-by: Jose A. Lopes <[email protected]> > --- > Makefile.am | 1 + > src/Ganeti/Metad/ConfigServer.hs | 196 > +++++++++++++++++++++++++++++++++++++++ > 2 files changed, 197 insertions(+) > create mode 100644 src/Ganeti/Metad/ConfigServer.hs > > diff --git a/Makefile.am b/Makefile.am > index 279013a..67b54fd 100644 > --- a/Makefile.am > +++ b/Makefile.am > @@ -773,6 +773,7 @@ HS_LIB_SRCS = \ > src/Ganeti/Logging.hs \ > src/Ganeti/Logging/Lifted.hs \ > src/Ganeti/Luxi.hs \ > + src/Ganeti/Metad/ConfigServer.hs \ > src/Ganeti/Metad/Types.hs \ > src/Ganeti/Metad/WebServer.hs \ > src/Ganeti/Monitoring/Server.hs \ > diff --git a/src/Ganeti/Metad/ConfigServer.hs > b/src/Ganeti/Metad/ConfigServer.hs > new file mode 100644 > index 0000000..b49c7d9 > --- /dev/null > +++ b/src/Ganeti/Metad/ConfigServer.hs > @@ -0,0 +1,196 @@ > +{-# LANGUAGE TupleSections #-} > +{-| Configuration server for the metadata daemon. > + > +-} > + > +{- > + > +Copyright (C) 2014 Google Inc. > + > +This program is free software; you can redistribute it and/or modify > +it under the terms of the GNU General Public License as published by > +the Free Software Foundation; either version 2 of the License, or > +(at your option) any later version. > + > +This program is distributed in the hope that it will be useful, but > +WITHOUT ANY WARRANTY; without even the implied warranty of > +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > +General Public License for more details. > + > +You should have received a copy of the GNU General Public License > +along with this program; if not, write to the Free Software > +Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA > +02110-1301, USA. > + > +-} > +module Ganeti.Metad.ConfigServer where > + > +import Control.Arrow (second) > +import Control.Concurrent > +import Control.Exception (try, finally) > +import Control.Monad (unless) > +import qualified Data.List as List > +import qualified Data.Map as Map > +import Text.JSON > +import qualified Text.JSON as JSON > +import System.FilePath ((</>)) > +import System.IO.Error (isEOFError) > + > +import Ganeti.Constants as Constants > +import Ganeti.Path as Path > +import Ganeti.Daemon (DaemonOptions) > +import qualified Ganeti.Logging as Logging > +import Ganeti.Runtime (GanetiDaemon(..)) > +import Ganeti.UDSServer (Client, ConnectConfig(..), Server) > +import qualified Ganeti.UDSServer as UDSServer > + > +import Ganeti.Metad.Types (InstanceParams) > + > +metadSocket :: IO FilePath > +metadSocket = > + do dir <- Path.socketDir > + return $ dir </> "ganeti-metad" > + > +mergeConfig :: InstanceParams -> InstanceParams -> InstanceParams > +mergeConfig cfg1 cfg2 = cfg2 `Map.union` cfg1 > + > +-- | Extracts the OS parameters (public, private, secret) from a JSON > +-- object. > +-- > +-- This function checks whether the OS parameters are in fact a JSON > +-- object. > +getOsParams :: String -> String -> JSObject JSValue -> Result (JSObject > JSValue) > +getOsParams key msg jsonObj = > + case lookup key (fromJSObject jsonObj) of > + Nothing -> Error $ "Could not find " ++ msg ++ " OS parameters" > + Just (JSObject x) -> Ok x > + _ -> Error "OS params is not a JSON object" > + > +getPublicOsParams :: JSObject JSValue -> Result (JSObject JSValue) > +getPublicOsParams = getOsParams "osparams" "public" > + > +getPrivateOsParams :: JSObject JSValue -> Result (JSObject JSValue) > +getPrivateOsParams = getOsParams "osparams_private" "private" > + > +getSecretOsParams :: JSObject JSValue -> Result (JSObject JSValue) > +getSecretOsParams = getOsParams "osparams_secret" "secret" > + > +-- | Finds the IP address of the instance communication NIC in the > +-- instance's NICs. > +getInstanceCommunicationIp :: JSObject JSValue -> Result String > +getInstanceCommunicationIp jsonObj = > + getNics >>= getInstanceCommunicationNic >>= getIp > + where > + getIp nic = > + case lookup "ip" (fromJSObject nic) of > + Nothing -> Error "Could not find instance communication IP" > + Just (JSString ip) -> Ok (JSON.fromJSString ip) > + _ -> Error "Instance communication IP is not a string" > + > + getInstanceCommunicationNic [] = > + Error "Could not find instance communication NIC" > + getInstanceCommunicationNic (JSObject nic:nics) = > + case lookup "name" (fromJSObject nic) of > + Just (JSString name) > + | Constants.instanceCommunicationNicPrefix > + `List.isPrefixOf` JSON.fromJSString name -> > + Ok nic > + _ -> getInstanceCommunicationNic nics > + getInstanceCommunicationNic (_:nics) = > + getInstanceCommunicationNic nics > Why not an error here? > + > + getNics = > + case lookup "nics" (fromJSObject jsonObj) of > + Nothing -> Error "Could not find OS parameters key 'nics'" > + Just (JSArray nics) -> Ok nics > + _ -> Error "Instance nics is not an array" > + > +-- | Merges the OS parameters (public, private, secret) in a single > +-- data structure containing all parameters and their visibility. > +-- > +-- Example: > +-- { "os-image": ["http://example.com/disk.img";, "public"], > +-- "os-password": ["mypassword", "secret"] } > +makeInstanceParams > + :: JSObject JSValue -> JSObject JSValue -> JSObject JSValue -> JSValue > +makeInstanceParams pub priv sec = > + JSObject . JSON.toJSObject $ > + addVisibility "public" pub ++ > + addVisibility "private" priv ++ > + addVisibility "secret" sec > + where > + key = JSString . JSON.toJSString > + > + addVisibility param params = > + map (second (JSArray . (:[key param]))) (JSON.fromJSObject params) > + > +-- | Extracts the OS parameters from the instance's parameters and > +-- returns a data structure containing all the OS parameters and their > +-- visibility indexed by the instance's IP address which is used in > +-- the instance communication NIC. > +getInstanceParams :: JSValue -> Result (String, InstanceParams) > +getInstanceParams json = > + case json of > + JSObject jsonObj -> do > + name <- case lookup "name" (fromJSObject jsonObj) of > + Nothing -> Error "Could not find instance name" > + Just (JSString x) -> Ok (JSON.fromJSString x) > + _ -> Error "Name is not a string" > + ip <- getInstanceCommunicationIp jsonObj > + publicOsParams <- getPublicOsParams jsonObj > + privateOsParams <- getPrivateOsParams jsonObj > + secretOsParams <- getSecretOsParams jsonObj > + let instanceParams = > + makeInstanceParams publicOsParams privateOsParams > secretOsParams > + Ok (name, Map.fromList [(ip, instanceParams)]) > + _ -> > + Error "Expecting a dictionary" > + > +-- | Update the configuration with the received instance parameters. > +updateConfig :: MVar InstanceParams -> String -> IO () > +updateConfig config str = > + case decode str of > + Error err -> > + Logging.logDebug $ show err > + Ok x -> > + case getInstanceParams x of > + Error err -> > + Logging.logError $ "Could not get instance parameters: " ++ err > + Ok (name, instanceParams) -> do > + cfg <- takeMVar config > + let cfg' = mergeConfig cfg instanceParams > + putMVar config cfg' > + Logging.logInfo $ > + "Updated instance " ++ show name ++ " configuration" > + Logging.logDebug $ "Instance configuration: " ++ show cfg' > + > +-- | Reads messages from clients and update the configuration > +-- according to these messages. > +acceptConfig :: MVar InstanceParams -> Client -> IO () > +acceptConfig config client = > + do res <- try $ UDSServer.recvMsg client > + case res of > + Left err -> do > + unless (isEOFError err) . > + Logging.logDebug $ show err > + return () > + Right str -> do > + Logging.logDebug $ "Received: " ++ str > + updateConfig config str > + > +-- | Loop that accepts clients and dispatches them to an isolated > +-- thread that will handle the client's requests. > +acceptClients :: MVar InstanceParams -> Server -> IO () > +acceptClients config server = > + do client <- UDSServer.acceptClient server > + _ <- forkIO $ acceptConfig config client > + acceptClients config server > + > +start :: DaemonOptions -> MVar InstanceParams -> IO () > +start _ config = > + do server <- UDSServer.connectServer metadConfig True =<< metadSocket > + finally > + (acceptClients config server) > + (UDSServer.closeServer server) > + where > + metadConfig = ConnectConfig GanetiMetad 60 60 > -- > 1.9.1.423.g4596e3a > >
