libnix (empty) → 0.2.0.0

raw patch · 9 files changed

+1322/−0 lines, 9 filesdep +aesondep +basedep +directorysetup-changed

Dependencies added: aeson, base, directory, errors, filepath, libnix, process, protolude, tasty, tasty-hunit, text

Files

• Foreign/Nix/Shellout.hs +161/−0
• Foreign/Nix/Shellout/Helpers.hs +105/−0
• Foreign/Nix/Shellout/Prefetch.hs +176/−0
• Foreign/Nix/Shellout/Types.hs +34/−0
• LICENSE +674/−0
• Setup.hs +2/−0
• libnix.cabal +57/−0
• tests/Main.hs +8/−0
• tests/TestShellout.hs +105/−0

@@ -0,0 +1,161 @@+{-|+Module      : Foreign.Nix.Shellout+Description : Interface to the nix package manager’s CLI+Copyright   : Profpatsch, 2016–2018+License     : GPL-3+Stability   : experimental+Portability : nix 1.11.x, nix 2.0++Calls to the nix command line to convert+textual nix expressions to derivations & realized storepaths.+-}+module Foreign.Nix.Shellout+( -- * Calling nix+  -- ** Parse+  parseNixExpr, ParseError(..)+  -- ** Instantiate+, instantiate, InstantiateError(..)+, eval+  -- ** Realize+, realize, RealizeError(..)+  -- ** Helpers+, addToStore+, parseInstRealize+, NixError(..)+  -- * Types+, StorePath(fromStorePath), Derivation, Realized+, NixExpr+, runNixAction, NixAction(..)+) where++import Protolude hiding (show, isPrefixOf)+import Control.Error hiding (bool, err)+import Data.String (String)+import Data.Text (stripPrefix, lines, isPrefixOf)+import System.FilePath (isValid)+import Text.Show (Show(..))++import qualified Foreign.Nix.Shellout.Helpers as Helpers+import Foreign.Nix.Shellout.Types++------------------------------------------------------------------------------+-- Parsing++-- | A sucessfully parsed nix expression.+newtype NixExpr = NixExpr Text deriving (Show, Eq)++data ParseError+  = SyntaxError Text+    -- ^ the input string was not a syntactically valid nix expression+  | UnknownParseError+    -- ^ catch-all error+  deriving (Show, Eq)++-- | Parse a nix expression and check for syntactic validity.+parseNixExpr :: Text -> NixAction ParseError NixExpr+parseNixExpr e =+  bimap parseParseError NixExpr+    $ evalNixOutput "nix-instantiate" [ "--parse", "-E", e ]+++parseParseError :: Text -> ParseError+parseParseError+  (stripPrefix "error: syntax error, "+               -> Just mes) = SyntaxError $ mes+parseParseError _           = UnknownParseError++------------------------------------------------------------------------------+-- Instantiating++data InstantiateError+  = NotADerivation+    -- ^ the given expression does not evaluate to a derivaton+  | UnknownInstantiateError+    -- ^ catch-all error+  deriving (Show, Eq)++-- | Instantiate a parsed expression into a derivation.+instantiate :: NixExpr -> NixAction InstantiateError (StorePath Derivation)+instantiate (NixExpr e) =+  first parseInstantiateError+    $ evalNixOutput "nix-instantiate" [ "-E", e ]+      >>= toNixFilePath StorePath++-- | Just tests if the expression can be evaluated.+-- That doesn’t mean it has to instantiate however.+eval :: NixExpr -> NixAction InstantiateError ()+eval (NixExpr e) =+  void $ first parseInstantiateError+       $ evalNixOutput "nix-instantiate" [ "--eval", "-E", e ]++parseInstantiateError :: Text -> InstantiateError+parseInstantiateError+  (stripPrefix "error: expression does not evaluate to a derivation"+               -> Just _) = NotADerivation+parseInstantiateError _   = UnknownInstantiateError+++------------------------------------------------------------------------------+-- Realizing++data RealizeError = UnknownRealizeError deriving (Show, Eq)++-- | Finally derivations are realized into full store outputs.+-- This will typically take a while so it should be executed asynchronously.+realize :: StorePath Derivation -> NixAction RealizeError (StorePath Realized)+realize (StorePath d) =+     storeOp [ "-r", toS d ]++-- | Copy the given file or folder to the nix store and return it’s path.+addToStore :: FilePath -> NixAction RealizeError (StorePath Realized)+addToStore fp = storeOp [ "--add", toS fp ]++storeOp :: [Text] -> NixAction RealizeError (StorePath Realized)+storeOp op =+  first (const UnknownRealizeError)+    $ evalNixOutput "nix-store" op+      >>= toNixFilePath StorePath++------------------------------------------------------------------------------+-- Convenience++-- | Combines all error types that could happen.+data NixError+  = ParseError ParseError+  | InstantiateError InstantiateError+  | RealizeError RealizeError deriving (Show, Eq)++-- | A convenience function to directly realize a nix expression.+-- Any errors are put into a combined error type.+parseInstRealize :: Text -> NixAction NixError (StorePath Realized)+parseInstRealize = first ParseError . parseNixExpr+               >=> first InstantiateError . instantiate+               >=> first RealizeError . realize++------------------------------------------------------------------------------+-- Helpers++-- | Take args and return either error message or output path+evalNixOutput :: Text+              -- ^ name of executable+              -> [Text]+              -- ^ arguments+              -> NixAction Text Text+              -- ^ error: (stderr, errormsg), success: path+evalNixOutput = Helpers.readProcess (\(out, err) -> \case+  ExitFailure _ -> throwE $+    case mconcat . intersperse "\n"+      . dropWhile (not . isPrefixOf "error: ")+      . lines $ toS err of+      "" -> "nix didn’t output any error message"+      s  -> s+  ExitSuccess -> tryLast+      "nix didn’t output a store path" (lines $ toS out))+++-- | Apply filePath p to constructor a if it’s a valid filepath+toNixFilePath :: (String -> a) -> Text -> NixAction Text a+toNixFilePath a p@(toS -> ps) = NixAction $+  if isValid ps then (pure $ a ps)+  else (throwE $ (nostderr, p <> " is not a filepath!"))+  where nostderr = mempty

@@ -0,0 +1,105 @@+module Foreign.Nix.Shellout.Helpers where++import Protolude hiding (async, wait)+import Foreign.Nix.Shellout.Types+import qualified System.Process as P+import qualified Data.Text.IO as TIO+import qualified Data.Text as T+import qualified System.IO as SIO++-- needed for ignoreSigPipe+import GHC.IO.Exception (IOErrorType(..), IOException(..))+import Foreign.C.Error (Errno(Errno), ePIPE)++-- | Read the output of a process into a NixAction.+-- | Keeps stderr if process returns a failure exit code.+-- | The text is decoded as @UTF-8@.+readProcess :: ((Text, Text) -> ExitCode -> ExceptT e IO a)+            -- ^ handle (stdout, stderr) depending on the return value+            -> Text+            -- ^ name of executable+            -> [Text]+            -- ^ arguments+            -> NixAction e a+            -- ^ error: (stderr, errormsg), success: path+readProcess with exec args = NixAction $ do+  (exc, out, err) <- liftIO+    $ readCreateProcessWithExitCodeAndEncoding+        (P.proc (toS exec) (map toS args)) SIO.utf8 ""+  withExceptT (err,) $ with (out, err) exc+++-- Copied & modified from System.Process (process-1.6.4.0)++-- | like @readCreateProcessWithExitCodeAndEncoding, but uses+-- | Text instead of [Char] and lets the user specify an encoding+-- | for the handles.+readCreateProcessWithExitCodeAndEncoding+    :: P.CreateProcess+    -> SIO.TextEncoding            -- ^ encoding for handles+    -> Text                        -- ^ standard input+    -> IO (ExitCode, Text, Text)   -- ^ exitcode, stdout, stderr+readCreateProcessWithExitCodeAndEncoding cp encoding input = do+    let cp_opts = cp+          { P.std_in  = P.CreatePipe+          , P.std_out = P.CreatePipe+          , P.std_err = P.CreatePipe }+    -- todo: this is not exposed by System.Process+    -- withCreateProcess_ "readCreateProcessWithExitCode" cp_opts $+    P.withCreateProcess cp_opts $+      \(Just inh) (Just outh) (Just errh) ph -> do++        SIO.hSetEncoding outh encoding+        SIO.hSetEncoding errh encoding+        SIO.hSetEncoding inh encoding++        out <- TIO.hGetContents outh+        err <- TIO.hGetContents errh++        -- fork off threads to start consuming stdout & stderr+        withForkWait  (evaluate $ rnf out) $ \waitOut ->+         withForkWait (evaluate $ rnf err) $ \waitErr -> do++          -- now write any input+          unless (T.null input) $+            ignoreSigPipe $ hPutStr inh input+          -- hClose performs implicit hFlush, and thus may trigger a SIGPIPE+          ignoreSigPipe $ SIO.hClose inh++          -- wait on the output+          waitOut+          waitErr++          -- TODO: isn’t this done by `withCreateProcess`?+          SIO.hClose outh+          SIO.hClose errh++        -- wait on the process+        ex <- P.waitForProcess ph++        return (ex, out, err)+++-- Copied from System.Process (process-1.6.4.0)++-- | Fork a thread while doing something else, but kill it if there's an+-- exception.+--+-- This is important in the cases above because we want to kill the thread+-- that is holding the Handle lock, because when we clean up the process we+-- try to close that handle, which could otherwise deadlock.+--+withForkWait :: IO () -> (IO () ->  IO a) -> IO a+withForkWait async body = do+  waitVar <- newEmptyMVar :: IO (MVar (Either SomeException ()))+  mask $ \restore -> do+    tid <- forkIO $ try (restore async) >>= putMVar waitVar+    let wait = takeMVar waitVar >>= either throwIO return+    restore (body wait) `onException` killThread tid++ignoreSigPipe :: IO () -> IO ()+ignoreSigPipe = handle $ \e -> case e of+  IOError { ioe_type  = ResourceVanished+          , ioe_errno = Just ioe }+    | Errno ioe == ePIPE -> return ()+  _ -> throwIO e

@@ -0,0 +1,176 @@+{-|+Description : Wrapper for the @nix-prefetch@ CLI utilities+Copyright   : Profpatsch, 2018+License     : GPL-3+Stability   : experimental+Portability : nix-prefetch-scripts 2018 (no version number)++Calls to the @nix-prefetch-X@ utilities, to parse their output+into nice reusable data types.+-}+{-# LANGUAGE RecordWildCards, GeneralizedNewtypeDeriving, ApplicativeDo #-}+module Foreign.Nix.Shellout.Prefetch+( -- * nix-prefetch-url+  url, UrlOptions(..), defaultUrlOptions+  -- * nix-prefetch-git+, git, GitOptions(..), defaultGitOptions, GitOutput(..)+  -- * Types+, PrefetchError(..)+, Url(..), Sha256(..)+  -- * Reexports+, runNixAction, NixAction(..)+) where++import Protolude+import Control.Error hiding (bool, err)+import qualified Data.Text as T++import qualified Data.Aeson as Aeson+import qualified Data.Aeson.Types as AesonT++import Foreign.Nix.Shellout.Types+import qualified Foreign.Nix.Shellout.Helpers as Helpers++data PrefetchError+  = PrefetchOutputMalformed Text+    -- ^ the tool’s output could not be parsed as expected+  | ExpectedHashError+    -- ^ an expected hash was given and not valid+  | UnknownPrefetchError+    -- ^ catch-all error+  deriving (Eq, Show)++-- | A descriptive type for URLs.+newtype Url = Url { unUrl :: Text } deriving (Show, Eq, IsString)+-- | A @sha-256@ hash.+newtype Sha256 = Sha256 { unSha256 :: Text } deriving (Show, Eq, IsString)++data UrlOptions = UrlOptions+  { urlUrl :: Url+    -- ^ the URL+  , urlUnpack :: Bool+    -- ^ whether to unpack before hashing (useful for prefetching @fetchTarball@)+  , urlName :: Maybe Text+    -- ^ name of the store path+  , urlExpectedHash :: Maybe Sha256+    -- ^ the hash we are expecting+  }++-- | Takes the URL, doesn’t unpack and uses the default name.+defaultUrlOptions :: Url -> UrlOptions+defaultUrlOptions u = UrlOptions+  { urlUrl = u+  , urlUnpack = False+  , urlName = Nothing+  , urlExpectedHash = Nothing }++-- | Runs @nix-prefetch-url@.+url :: UrlOptions -> NixAction PrefetchError (Sha256, StorePath Realized)+url UrlOptions{..} = Helpers.readProcess handler exec args+  where+    exec = "nix-prefetch-url"+    args =  bool [] ["--unpack"] urlUnpack+         <> maybe [] (\n -> ["--name", n]) urlName+         <> [ "--type", "sha256"+            , "--print-path"+            , unUrl urlUrl ]+         <> maybe [] (pure.unSha256) urlExpectedHash++    handler (out, err) = \case+      ExitSuccess -> withExceptT PrefetchOutputMalformed $ do+        let ls = T.lines $ T.stripEnd out+        path <- tryLast (exec <> " didn’t output a store path") ls+        sha  <- let errS = (exec <> " didn’t output a hash")+                in tryInit errS ls >>= tryLast errS+        pure (Sha256 sha, StorePath $ toS path)+      ExitFailure _ -> throwE $+        if "error: hash mismatch" `T.isPrefixOf` err+        then ExpectedHashError+        else UnknownPrefetchError+++data GitOptions = GitOptions+  { gitUrl :: Url+    -- ^ the URL+  , gitRev :: Maybe Text+    -- ^ a git revision (hash, branch name, tag, ref, …)+  , gitExpectedHash :: Maybe Sha256+    -- ^ the hash we are expecting+  , gitDeepClone :: Bool+    -- ^ whether to do a deep instead of a shallow (@--depth=1@) git clone+  , gitLeaveDotGit :: Bool+    -- ^ whether to keep @.git@ directories+  , gitFetchSubmodules :: Bool+    -- ^ whether to fetch submodules+  }++-- | Takes the url, mirrors the default `fetchgit` options in nixpkgs:+-- no deep clone, no @.git@, fetches submodules by default.+-- By default, the latest default @rev@ is used.+defaultGitOptions :: Url -> GitOptions+defaultGitOptions u = GitOptions+  { gitUrl = u+  , gitRev = Nothing+  , gitExpectedHash = Nothing+  , gitDeepClone = False+  , gitLeaveDotGit = False+  , gitFetchSubmodules = True }++data GitOutput = GitOutput+  { gitOutputRev :: Text+    -- ^ The actual revision that is used (useful if no 'gitRev' was given)+  , gitOutputSha256 :: Sha256+    -- ^ the hash+  , gitOuputPath :: StorePath Realized+    -- ^ the store path of the result+  } deriving (Show, Eq)++-- | Runs @nix-prefetch-git@.+git :: GitOptions -> NixAction PrefetchError GitOutput+git GitOptions{..} = Helpers.readProcess handler exec args+  where+    exec = "nix-prefetch-git"+    args =  bool ["--no-deepClone"] ["--deepClone"] gitDeepClone+         <> bool [] ["--leave-dotGit"] gitLeaveDotGit+         <> bool [] ["--fetch-submodules"] gitFetchSubmodules+         <> [ "--hash", "sha256" -- --hash is the type, not the thing+            -- we need @url [rev [hash]]@,+            -- otherwise we can’t expect a hash+            , unUrl gitUrl+            , maybe "" identity gitRev ]+            -- hash comes last+         <> maybe [] (\(Sha256 h) -> [h]) gitExpectedHash++    handler (out, err) = \case+      ExitSuccess -> withExceptT PrefetchOutputMalformed $ do+        let error msg = exec <> " " <> msg+            jsonError :: [Char] -> Text+            jsonError = \msg -> error (T.intercalate "\n"+                      [ "parsing json output failed:"+                      , toS msg+                      , "The output was:"+                      , out ])++        (gitOutputRev, gitOutputSha256)+          <- ExceptT . pure . first jsonError $ do+            val <- Aeson.eitherDecode' (toS out)+            flip AesonT.parseEither val+              $ Aeson.withObject "GitPrefetchOutput" $ \obj -> do+                    (,) <$> obj Aeson..: "rev"+                        <*> fmap Sha256 (obj Aeson..: "sha256")++        -- The path isn’t output in the json, but on stderr. :(+        -- So this is a bit more hacky than necessary.+        gitOuputPath <- case+          find ("path is /nix/store" `T.isPrefixOf`) (T.lines err)+          >>= T.stripPrefix "path is " of+          Nothing -> throwE+            $ error "could not find nix store output path on stderr"+          Just path -> pure $ StorePath $ toS path++        pure GitOutput{..}++      ExitFailure _ -> throwE $+        if ("hash mismatch for URL" `T.isInfixOf` err)+        then ExpectedHashError+        else UnknownPrefetchError

@@ -0,0 +1,34 @@+{-|+Description : Common Types+Copyright   : Profpatsch, 2018+License     : GPL-3+Stability   : experimental+-}+{-# LANGUAGE GeneralizedNewtypeDeriving #-}+module Foreign.Nix.Shellout.Types where++import Protolude+import Control.Error++-- | Calls a command that returns an error and the whole stderr on failure.+newtype NixAction e a = NixAction+  { unNixAction :: ExceptT (Text, e) IO a }+  deriving (Functor, Applicative, Monad, MonadIO)++-- | Run a 'NixAction' without having to go through 'ExceptT' first.+runNixAction :: NixAction e a -> IO (Either (Text, e) a)+runNixAction = runExceptT . unNixAction++instance Bifunctor NixAction where+  bimap f g = NixAction . bimapExceptT (fmap f) g . unNixAction++-- | A path in the nix store. It carries a phantom @a@ to differentiate+-- between 'Derivation' files and 'Realized' paths.+newtype StorePath a = StorePath+  { fromStorePath :: FilePath }+  deriving (Eq, Show)++-- | A nix derivation is a complete build instruction that can be realized.+data Derivation+-- | Once a derivation is realized, the finished output can be used.+data Realized

@@ -0,0 +1,674 @@+              GNU GENERAL PUBLIC LICENSE+                Version 3, 29 June 2007++ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>+ Everyone is permitted to copy and distribute verbatim copies+ of this license document, but changing it is not allowed.++                     Preamble++  The GNU General Public License is a free, copyleft license for+software and other kinds of works.++  The licenses for most software and other practical works are designed+to take away your freedom to share and change the works.  By contrast,+the GNU General Public License is intended to guarantee your freedom to+share and change all versions of a program--to make sure it remains free+software for all its users.  We, the Free Software Foundation, use the+GNU General Public License for most of our software; it applies also to+any other work released this way by its authors.  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@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain

@@ -0,0 +1,57 @@+-- Initial libnix.cabal generated by cabal init.  For further +-- documentation, see http://haskell.org/cabal/users-guide/++name:                libnix+version:             0.2.0.0+synopsis:            Bindings to the nix package manager+-- description:       +license:             GPL-3+license-file:        LICENSE+author:              Profpatsch+maintainer:          mail@profpatsch.de+-- copyright:           +category:            Foreign, Nix+build-type:          Simple+-- extra-source-files:  +cabal-version:       >=1.10++library+  exposed-modules:     Foreign.Nix.Shellout+                     , Foreign.Nix.Shellout.Prefetch+                     , Foreign.Nix.Shellout.Types+  other-modules:       Foreign.Nix.Shellout.Helpers+  build-depends:       base >=4.9 && <5+                     , aeson >=1.0.0.0 && <1.5.0.0+                     , errors >=2.2.0 && <2.4.0+                     , filepath+                     , protolude ==0.2.*+                     , process+                     , text+  -- hs-source-dirs:      +  ghc-options:        -Wall+  default-extensions:  NoImplicitPrelude+                     , OverloadedStrings+                     , LambdaCase+                     , TupleSections+                     , ViewPatterns+  default-language:    Haskell2010++test-suite tests+  type:                exitcode-stdio-1.0+  main-is:             Main.hs+  hs-source-dirs:      tests+  other-modules:       TestShellout+  build-depends:       base+                     , directory+                     , errors+                     , text+                     , libnix+                     , protolude+                     , tasty+                     , tasty-hunit+  ghc-options:        -threaded -rtsopts -with-rtsopts=-N -Wall+  default-extensions:  NoImplicitPrelude+                     , OverloadedStrings+                     , LambdaCase+                     , TupleSections+  default-language:    Haskell2010

@@ -0,0 +1,8 @@+module Main where++import Prelude+import TestShellout+import Test.Tasty++main :: IO ()+main = defaultMain shelloutTests

@@ -0,0 +1,105 @@+module TestShellout where++import Protolude hiding (check)+import qualified Data.Text as T+import System.IO (openTempFile, hClose)+import System.Directory (getTemporaryDirectory)++import Test.Tasty+import Test.Tasty.HUnit++import Foreign.Nix.Shellout+++shelloutTests :: TestTree+shelloutTests = testGroup "shellout tests"+  [ testGroup "parsing"+    [ syntaxError ]+  , testGroup "evaluating"+    [ infiniteRecursion+    , notADerivation+    , someDerivation ]+  , testGroup "realizing"+    [ nixpkgsExists+    , multilineErrors+    , helloWorld+    , copyTempfileToStore ]+  ]++syntaxError, infiniteRecursion, notADerivation, someDerivation :: TestTree+nixpkgsExists, multilineErrors, helloWorld, copyTempfileToStore :: TestTree++syntaxError = testCase "syntax error"+  $ parseNixExpr ";"+  `isE` (Left ("", SyntaxError "unexpected ';', at (string):1:1"))++infiniteRecursion = testCase "infinite recursion"+  $ parseInst "let a = a; in a"+  `isE` (Left ( "error: infinite recursion encountered, at (string):1:10"+              , UnknownInstantiateError))++notADerivation = testCase "not a derivation"+  $ parseInst "42"+  `isE` (Left ("", NotADerivation))++someDerivation = testCase "a basic derivation"+  $ assertNoFailure $ parseInst+      "derivation { name = \"foo\"; builder = \" \"; system = \" \"; }"++nixpkgsExists = testCase "nixpkgs is accessible"+  $ assertNoFailure $ parseEval "import <nixpkgs> {}"++multilineErrors = testCase "nixpkgs multiline stderr it parsed"+  $ parseEval "builtins.abort ''wow\nsuch error''"+  `isE` (Left+           ( "error: evaluation aborted with the following error \+             \message: 'wow\nsuch error'"+           , UnknownInstantiateError))++helloWorld = testCase "build the GNU hello package"+  $ assertNoFailure $ parseInstRealize "with import <nixpkgs> {}; hello"++copyTempfileToStore = testCase "copy a temporary file to store"+  $ assertNoFailure $ do+    (fp, h) <- liftIO $+      getTemporaryDirectory >>= flip openTempFile "store-test"+    liftIO $ hClose h+    addToStore fp+++--------------------------------------------------------------------+-- Helpers++parseInst :: Text -> NixAction InstantiateError (StorePath Derivation)+parseInst = parseInstLike instantiate++parseEval :: Text -> NixAction InstantiateError ()+parseEval = parseInstLike eval++parseInstLike :: (NixExpr -> NixAction InstantiateError a)+              -> Text+              -> NixAction InstantiateError a+parseInstLike like =+  first (\_ -> UnknownInstantiateError)+              . parseNixExpr >=> like++isE :: (Eq e, Eq a, Show a, Show e)+    => NixAction e a+    -> Either (Text, e) a+       -- ^ Left (subset of stdout, error)+    -> Assertion+isE na match = runExceptT (unNixAction na) >>= check match+  where+    check (Left (outMatch, err)) (Left (out, err')) = do+      assertBool "stderr not matched" (outMatch `T.isInfixOf` out)+      err @=? err'+    check (Right _) (Left _) =+      assertFailure "output should have succeeded, but is failed"+    check a b = a @=? b++assertNoFailure :: Show e => NixAction e a -> Assertion+assertNoFailure na = do+  ei <- runExceptT (unNixAction na)+  case ei of+    (Left (_, e)) -> assertFailure $ show e+    (Right _) -> pure ()