git-annex/Assistant/XMPP.hs
2012-11-10 02:35:54 -04:00

231 lines
7.2 KiB
Haskell

{- core xmpp support
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE OverloadedStrings #-}
module Assistant.XMPP where
import Assistant.Common
import Assistant.Types.NetMessager
import Assistant.Pairing
import Network.Protocol.XMPP hiding (Node)
import Data.Text (Text)
import qualified Data.Text as T
import Data.ByteString (ByteString)
import qualified Data.ByteString as B
import Data.XML.Types
import qualified Codec.Binary.Base64 as B64
{- Name of the git-annex tag, in our own XML namespace.
- (Not using a namespace URL to avoid unnecessary bloat.) -}
gitAnnexTagName :: Name
gitAnnexTagName = "{git-annex}git-annex"
{- Creates a git-annex tag containing a particular attribute and value. -}
gitAnnexTag :: Name -> Text -> Element
gitAnnexTag attr val = gitAnnexTagContent attr val []
{- Also with some content. -}
gitAnnexTagContent :: Name -> Text -> [Node] -> Element
gitAnnexTagContent attr val = Element gitAnnexTagName [(attr, [ContentText val])]
isGitAnnexTag :: Element -> Bool
isGitAnnexTag t = elementName t == gitAnnexTagName
{- Things that a git-annex tag can inserted into. -}
class GitAnnexTaggable a where
insertGitAnnexTag :: a -> Element -> a
extractGitAnnexTag :: a -> Maybe Element
hasGitAnnexTag :: a -> Bool
hasGitAnnexTag = isJust . extractGitAnnexTag
instance GitAnnexTaggable Message where
insertGitAnnexTag m elt = m { messagePayloads = elt : messagePayloads m }
extractGitAnnexTag = headMaybe . filter isGitAnnexTag . messagePayloads
instance GitAnnexTaggable Presence where
-- always mark extended away
insertGitAnnexTag p elt = p { presencePayloads = extendedAway : elt : presencePayloads p }
extractGitAnnexTag = headMaybe . filter isGitAnnexTag . presencePayloads
data GitAnnexTagInfo = GitAnnexTagInfo
{ tagAttr :: Name
, tagValue :: Text
, tagElement :: Element
}
gitAnnexTagInfo :: GitAnnexTaggable a => a -> Maybe GitAnnexTagInfo
gitAnnexTagInfo v = case extractGitAnnexTag v of
{- Each git-annex tag has a single attribute. -}
Just (tag@(Element _ [(attr, _)] _)) -> GitAnnexTagInfo
<$> pure attr
<*> attributeText attr tag
<*> pure tag
_ -> Nothing
{- A presence with a git-annex tag in it. -}
gitAnnexPresence :: Element -> Presence
gitAnnexPresence = insertGitAnnexTag $ emptyPresence PresenceAvailable
{- A presence with an empty git-annex tag in it, used for letting other
- clients know we're around and are a git-annex client. -}
gitAnnexSignature :: Presence
gitAnnexSignature = gitAnnexPresence $ Element gitAnnexTagName [] []
{- A message with a git-annex tag in it. -}
gitAnnexMessage :: Element -> JID -> JID -> Message
gitAnnexMessage elt tojid fromjid = (insertGitAnnexTag silentMessage elt)
{ messageTo = Just tojid
, messageFrom = Just fromjid
}
{- A notification that we've pushed to some repositories, listing their
- UUIDs. -}
pushNotification :: [UUID] -> Presence
pushNotification = gitAnnexPresence . gitAnnexTag pushAttr . encodePushNotification
pushAttr :: Name
pushAttr = "push"
uuidSep :: Text
uuidSep = ","
encodePushNotification :: [UUID] -> Text
encodePushNotification = T.intercalate uuidSep . map (T.pack . fromUUID)
decodePushNotification :: Text -> [UUID]
decodePushNotification = map (toUUID . T.unpack) . T.splitOn uuidSep
{- A request for other git-annex clients to send presence. -}
presenceQuery :: Presence
presenceQuery = gitAnnexPresence $ gitAnnexTag queryAttr T.empty
queryAttr :: Name
queryAttr = "query"
{- A notification about a stage of pairing. -}
pairingNotification :: PairStage -> UUID -> JID -> JID -> Message
pairingNotification pairstage u = gitAnnexMessage $
gitAnnexTag pairAttr $ encodePairingNotification pairstage u
pairAttr :: Name
pairAttr = "pair"
encodePairingNotification :: PairStage -> UUID -> Text
encodePairingNotification pairstage u = T.unwords $ map T.pack
[ show pairstage
, fromUUID u
]
decodePairingNotification :: Message -> GitAnnexTagInfo -> Maybe NetMessage
decodePairingNotification m = parse . words . T.unpack . tagValue
where
parse [stage, u] = PairingNotification
<$> readish stage
<*> (formatJID <$> messageFrom m)
<*> pure (toUUID u)
parse _ = Nothing
canPush :: JID -> JID -> Message
canPush = gitAnnexMessage $ gitAnnexTag canPushAttr T.empty
decodeCanPush :: Message -> GitAnnexTagInfo -> Maybe NetMessage
decodeCanPush m _ = CanPush <$> (formatJID <$> messageFrom m)
canPushAttr :: Name
canPushAttr = "canpush"
pushRequest :: JID -> JID -> Message
pushRequest = gitAnnexMessage $ gitAnnexTag pushRequestAttr T.empty
decodePushRequest :: Message -> GitAnnexTagInfo -> Maybe NetMessage
decodePushRequest m _ = PushRequest <$> (formatJID <$> messageFrom m)
pushRequestAttr :: Name
pushRequestAttr = "pushrequest"
startingPush :: JID -> JID -> Message
startingPush = gitAnnexMessage $ gitAnnexTag startingPushAttr T.empty
startingPushAttr :: Name
startingPushAttr = "startingpush"
decodeStartingPush :: Message -> GitAnnexTagInfo -> Maybe NetMessage
decodeStartingPush m _ = StartingPush <$> (formatJID <$> messageFrom m)
receivePackOutput :: ByteString -> JID -> JID -> Message
receivePackOutput = gitAnnexMessage .
gitAnnexTagContent receivePackAttr T.empty . encodeTagContent
receivePackAttr :: Name
receivePackAttr = "rp"
decodeReceivePackOutput :: Message -> GitAnnexTagInfo -> Maybe NetMessage
decodeReceivePackOutput m i = ReceivePackOutput
<$> (formatJID <$> messageFrom m)
<*> decodeTagContent (tagElement i)
sendPackOutput :: ByteString -> JID -> JID -> Message
sendPackOutput = gitAnnexMessage .
gitAnnexTagContent sendPackAttr T.empty . encodeTagContent
sendPackAttr :: Name
sendPackAttr = "sp"
decodeSendPackOutput :: Message -> GitAnnexTagInfo -> Maybe NetMessage
decodeSendPackOutput m i = SendPackOutput
<$> (formatJID <$> messageFrom m)
<*> decodeTagContent (tagElement i)
receivePackDone :: ExitCode -> JID -> JID -> Message
receivePackDone = gitAnnexMessage . gitAnnexTag receivePackDoneAttr . T.pack . show . toi
where
toi (ExitSuccess) = 0
toi (ExitFailure i) = i
decodeReceivePackDone :: Message -> GitAnnexTagInfo -> Maybe NetMessage
decodeReceivePackDone m i = ReceivePackDone
<$> (formatJID <$> messageFrom m)
<*> (convert <$> readish (T.unpack $ tagValue i))
where
convert 0 = ExitSuccess
convert n = ExitFailure n
receivePackDoneAttr :: Name
receivePackDoneAttr = "rpdone"
{- Base 64 encoding a ByteString to use as the content of a tag. -}
encodeTagContent :: ByteString -> [Node]
encodeTagContent b = [NodeContent $ ContentText $ T.pack $ B64.encode $ B.unpack b]
decodeTagContent :: Element -> Maybe ByteString
decodeTagContent elt = B.pack <$> B64.decode s
where
s = T.unpack $ T.concat $ elementText elt
{- The JID without the client part. -}
baseJID :: JID -> JID
baseJID j = JID (jidNode j) (jidDomain j) Nothing
{- An XMPP chat message with an empty body. This should not be displayed
- by clients, but can be used for communications. -}
silentMessage :: Message
silentMessage = (emptyMessage MessageChat)
{ messagePayloads = [ emptybody ] }
where
emptybody = Element
{ elementName = "body"
, elementAttributes = []
, elementNodes = []
}
{- Add to a presence to mark its client as extended away. -}
extendedAway :: Element
extendedAway = Element "show" [] [NodeContent $ ContentText "xa"]