git-annex/Logs/PreferredContent.hs
Joey Hess 3518c586cf fix transfers of key with no associated file
Several places assumed this would not happen, and when the AssociatedFile
was Nothing, did nothing.

As part of this, preferred content checks pass the Key around.

Note that checkMatcher is sometimes now called with Just Key and Just File.
It currently constructs a FileMatcher, ignoring the Key. However, if it
constructed a FileKeyMatcher, which contained both, then it might be
possible to speed up parts of Limit, which currently call the somewhat
expensive lookupFileKey to get the Key.

I have not made this optimisation yet, because I am not sure if the key is
always the same. Will need some significant checking to satisfy myself
that's the case..
2014-01-23 16:44:02 -04:00

101 lines
3.5 KiB
Haskell

{- git-annex preferred content matcher configuration
-
- Copyright 2012 Joey Hess <joey@kitenet.net>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Logs.PreferredContent (
preferredContentLog,
preferredContentSet,
isPreferredContent,
preferredContentMap,
preferredContentMapLoad,
preferredContentMapRaw,
checkPreferredContentExpression,
setStandardGroup,
) where
import qualified Data.Map as M
import qualified Data.Set as S
import Data.Either
import Common.Annex
import Logs.PreferredContent.Raw
import qualified Annex.Branch
import qualified Annex
import Logs
import Logs.UUIDBased
import qualified Utility.Matcher
import Annex.FileMatcher
import Annex.UUID
import Types.Limit
import Types.Group
import Types.Remote (RemoteConfig)
import Logs.Group
import Logs.Remote
import Types.StandardGroups
{- Checks if a file is preferred content for the specified repository
- (or the current repository if none is specified). -}
isPreferredContent :: Maybe UUID -> AssumeNotPresent -> Maybe Key -> AssociatedFile -> Bool -> Annex Bool
isPreferredContent mu notpresent mkey afile def = do
u <- maybe getUUID return mu
m <- preferredContentMap
case M.lookup u m of
Nothing -> return def
Just matcher -> checkMatcher matcher mkey afile notpresent def
{- The map is cached for speed. -}
preferredContentMap :: Annex Annex.PreferredContentMap
preferredContentMap = maybe preferredContentMapLoad return
=<< Annex.getState Annex.preferredcontentmap
{- Loads the map, updating the cache. -}
preferredContentMapLoad :: Annex Annex.PreferredContentMap
preferredContentMapLoad = do
groupmap <- groupMap
configmap <- readRemoteLog
m <- simpleMap
. parseLogWithUUID ((Just .) . makeMatcher groupmap configmap)
<$> Annex.Branch.get preferredContentLog
Annex.changeState $ \s -> s { Annex.preferredcontentmap = Just m }
return m
{- This intentionally never fails, even on unparsable expressions,
- because the configuration is shared among repositories and newer
- versions of git-annex may add new features. Instead, parse errors
- result in a Matcher that will always succeed. -}
makeMatcher :: GroupMap -> M.Map UUID RemoteConfig -> UUID -> PreferredContentExpression -> FileMatcher
makeMatcher groupmap configmap u expr
| expr == "standard" = standardMatcher groupmap configmap u
| null (lefts tokens) = Utility.Matcher.generate $ rights tokens
| otherwise = matchAll
where
tokens = exprParser groupmap configmap (Just u) expr
{- Standard matchers are pre-defined for some groups. If none is defined,
- or a repository is in multiple groups with standard matchers, match all. -}
standardMatcher :: GroupMap -> M.Map UUID RemoteConfig -> UUID -> FileMatcher
standardMatcher groupmap configmap u =
maybe matchAll (makeMatcher groupmap configmap u . preferredContent) $
getStandardGroup =<< u `M.lookup` groupsByUUID groupmap
{- Checks if an expression can be parsed, if not returns Just error -}
checkPreferredContentExpression :: PreferredContentExpression -> Maybe String
checkPreferredContentExpression expr
| expr == "standard" = Nothing
| otherwise = case parsedToMatcher tokens of
Left e -> Just e
Right _ -> Nothing
where
tokens = exprParser emptyGroupMap M.empty Nothing expr
{- Puts a UUID in a standard group, and sets its preferred content to use
- the standard expression for that group, unless something is already set. -}
setStandardGroup :: UUID -> StandardGroup -> Annex ()
setStandardGroup u g = do
groupSet u $ S.singleton $ fromStandardGroup g
m <- preferredContentMap
unless (isJust $ M.lookup u m) $
preferredContentSet u "standard"