git-annex/Assistant/XMPP.hs
2012-11-03 14:16:17 -04:00

114 lines
3.5 KiB
Haskell

{- core xmpp support
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Assistant.XMPP where
import Assistant.Common
import Annex.UUID
import Assistant.Pairing
import Network.Protocol.XMPP
import qualified Data.Text as T
import Data.XML.Types
{- A presence with a git-annex tag in it. -}
gitAnnexPresence :: Element -> Presence
gitAnnexPresence tag = (emptyPresence PresenceAvailable)
{ presencePayloads = [extendedAway, tag] }
where
extendedAway = Element (Name (T.pack "show") Nothing Nothing) []
[NodeContent $ ContentText $ T.pack "xa"]
{- Does a presence contain a git-annex tag? -}
isGitAnnexPresence :: Presence -> Bool
isGitAnnexPresence p = any isGitAnnexTag (presencePayloads p)
{- Name of a git-annex tag, in our own XML namespace.
- (Not using a namespace URL to avoid unnecessary bloat.) -}
gitAnnexTagName :: Name
gitAnnexTagName = Name (T.pack "git-annex") (Just $ T.pack "git-annex") Nothing
isGitAnnexTag :: Element -> Bool
isGitAnnexTag t = elementName t == gitAnnexTagName
{- A git-annex tag, to let other clients know we're a git-annex client too. -}
gitAnnexSignature :: Element
gitAnnexSignature = Element gitAnnexTagName [] []
queryAttr :: Name
queryAttr = Name (T.pack "query") Nothing Nothing
pushAttr :: Name
pushAttr = Name (T.pack "push") Nothing Nothing
pairingAttr :: Name
pairingAttr = Name (T.pack "pairing") Nothing Nothing
isAttr :: Name -> (Name, [Content]) -> Bool
isAttr attr (k, _) = k == attr
getAttr :: Name -> [(Name, [Content])] -> Maybe String
getAttr wantattr attrs = content <$> headMaybe (filter (isAttr wantattr) attrs)
where
content (_name, cs) = T.unpack $ T.concat $ map unpack cs
unpack (ContentText t) = t
unpack (ContentEntity t) = t
uuidAttr :: Name
uuidAttr = Name (T.pack "uuid") Nothing Nothing
uuidSep :: T.Text
uuidSep = T.pack ","
{- git-annex tag with one push attribute per UUID pushed to. -}
encodePushNotification :: [UUID] -> Element
encodePushNotification us = Element gitAnnexTagName
[(pushAttr, [ContentText pushvalue])] []
where
pushvalue = T.intercalate uuidSep $
map (T.pack . fromUUID) us
decodePushNotification :: Element -> Maybe [UUID]
decodePushNotification (Element name attrs _nodes)
| name == gitAnnexTagName && not (null us) = Just us
| otherwise = Nothing
where
us = map (toUUID . T.unpack) $
concatMap (T.splitOn uuidSep . T.concat . map fromContent . snd) $
filter ispush attrs
ispush (k, _) = k == pushAttr
fromContent (ContentText t) = t
fromContent (ContentEntity t) = t
{- A request for other git-annex clients to send presence. -}
presenceQuery :: Presence
presenceQuery = gitAnnexPresence $ Element gitAnnexTagName
[ (queryAttr, [ContentText T.empty]) ]
[]
isPresenceQuery :: Presence -> Bool
isPresenceQuery p = case filter isGitAnnexTag (presencePayloads p) of
[] -> False
((Element _name attrs _nodes):_) -> any (isAttr queryAttr) attrs
{- A notification about a stage of pairing. -}
pairingNotification :: PairStage -> Annex Presence
pairingNotification pairstage = do
u <- getUUID
return $ gitAnnexPresence $ Element gitAnnexTagName
[ (pairingAttr, [ContentText $ T.pack $ show pairstage])
, (uuidAttr, [ContentText $ T.pack $ fromUUID u])
]
[]
isPairingNotification :: Presence -> Maybe (PairStage, UUID)
isPairingNotification p = case filter isGitAnnexTag (presencePayloads p) of
[] -> Nothing
((Element _name attrs _nodes):_) ->
(,)
<$> (readish =<< getAttr pairingAttr attrs)
<*> (toUUID <$> getAttr uuidAttr attrs)