git-annex/Logs/View.hs
Joey Hess a11d6e0baf
avoid sync pushing view branches to remotes, and better view branch names
* sync: Avoid pushing view branches to remotes.
* Changed the name of view branches to include the parent branch.
  Existing view branches checked out using an old name will still work.

It does not seem useful for sync to push view branches around, because
the information in a view branch can entirely be derived from other
information in git. And sync doesn't push adjusted branches around either.

The better view branch names make it more in line with adjusted branch
names, but were also needed to make fromViewBranch be able to return the
original branch name.

Kept the old view branch names still working. But, when those branches
exist in a repo, sync will still try to push them as before. Avoiding
that would need more complicated and/or expensive changes to sync.

Sponsored-By: Boyd Stephen Smith Jr. on Patreon
2023-02-08 13:57:48 -04:00

130 lines
3.9 KiB
Haskell

{- git-annex recent views log
-
- The most recently accessed view comes first.
-
- This file is stored locally in .git/annex/, not in the git-annex branch.
-
- Copyright 2014-2023 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE OverloadedStrings #-}
module Logs.View (
currentView,
setView,
removeView,
recentViews,
branchView,
fromViewBranch,
is_branchView,
prop_branchView_legal,
) where
import Annex.Common
import Types.View
import Types.MetaData
import qualified Git
import qualified Git.Branch
import qualified Git.Ref
import Git.Types
import Logs.File
import qualified Data.Text as T
import qualified Data.Set as S
import Data.Char
import qualified Data.ByteString as B
setView :: View -> Annex ()
setView v = do
old <- take 99 . filter (/= v) <$> recentViews
writeViews (v : old)
writeViews :: [View] -> Annex ()
writeViews l = do
f <- fromRepo gitAnnexViewLog
writeLogFile f $ unlines $ map show l
removeView :: View -> Annex ()
removeView v = writeViews =<< filter (/= v) <$> recentViews
recentViews :: Annex [View]
recentViews = do
f <- fromRawFilePath <$> fromRepo gitAnnexViewLog
liftIO $ mapMaybe readish . lines <$> catchDefaultIO [] (readFile f)
{- Gets the currently checked out view, if there is one. -}
currentView :: Annex (Maybe View)
currentView = go =<< inRepo Git.Branch.current
where
go (Just b) | branchViewPrefix `B.isPrefixOf` fromRef' b =
headMaybe . filter (\v -> branchView v == b || branchViewOld v == b)
<$> recentViews
go _ = return Nothing
branchViewPrefix :: B.ByteString
branchViewPrefix = "refs/heads/views"
{- Generates a git branch name for a View.
-
- There is no guarantee that each view gets a unique branch name,
- but the branch name is used to express the view as well as possible
- given the constraints on git branch names. It includes the name of the
- parent branch, and what metadata is used.
-}
branchView :: View -> Git.Branch
branchView view = Git.Ref $
branchViewPrefix <> "/" <> basebranch
<> "(" <> branchViewDesc view False <> ")"
where
basebranch = fromRef' (Git.Ref.base (viewParentBranch view))
{- Old name used for a view did not include the name of the parent branch. -}
branchViewOld :: View -> Git.Branch
branchViewOld view = Git.Ref $
branchViewPrefix <> "/" <> branchViewDesc view True
branchViewDesc :: View -> Bool -> B.ByteString
branchViewDesc view pareninvisibles = encodeBS $
intercalate ";" $ map branchcomp (viewComponents view)
where
branchcomp c
| viewVisible c || not pareninvisibles = branchcomp' c
| otherwise = "(" ++ branchcomp' c ++ ")"
branchcomp' (ViewComponent metafield viewfilter _) = concat
[ forcelegal (T.unpack (fromMetaField metafield))
, branchvals viewfilter
]
branchvals (FilterValues set) = '=' : branchset set
branchvals (FilterGlob glob) = '=' : forcelegal glob
branchvals (ExcludeValues set) = "!=" ++ branchset set
branchvals (FilterValuesOrUnset set _) = '=' : branchset set
branchvals (FilterGlobOrUnset glob _) = '=' : forcelegal glob
branchset = intercalate ","
. map (forcelegal . decodeBS . fromMetaValue)
. S.toList
forcelegal s
| Git.Ref.legal True s = s
| otherwise = map (\c -> if isAlphaNum c then c else '_') s
is_branchView :: Git.Branch -> Bool
is_branchView (Ref b) = (branchViewPrefix <> "/") `B.isPrefixOf` b
{- Converts a view branch as generated by branchView (but not by
- branchViewOld) back to the parent branch.
- Has no effect on other branches. -}
fromViewBranch :: Git.Branch -> Git.Branch
fromViewBranch b =
let bs = fromRef' b
in if (branchViewPrefix <> "/") `B.isPrefixOf` bs
then
let (branch, _desc) = separate' (== openparen) (B.drop prefixlen bs)
in Ref branch
else b
where
prefixlen = B.length branchViewPrefix + 1
openparen = fromIntegral (ord '(')
prop_branchView_legal :: View -> Bool
prop_branchView_legal = Git.Ref.legal False . fromRef . branchView