Safe Haskell | Safe-Infered |
---|
- Entering ShIO.
- Running external commands.
- Modifying and querying environment.
- Environment directory
- Printing
- Querying filesystem.
- Finding files
- Filename helpers
- Manipulating filesystem.
- exiting the program
- Utilities.
- convert between Text and FilePath
- Re-exported for your convenience
- internal functions for writing extension
A module for shell-like / perl-like programming in Haskell. Shelly's focus is entirely on ease of use for those coming from shell scripting. However, it also tries to use modern libraries and techniques to keep things efficient.
The functionality provided by this module is (unlike standard Haskell filesystem functionality) thread-safe: each ShIO maintains its own environment and its own working directory.
I highly recommend putting the following at the top of your program, otherwise you will likely need either type annotations or type conversions
{-# LANGUAGE OverloadedStrings #-} {-# LANGUAGE ExtendedDefaultRules #-} {-# OPTIONS_GHC -fno-warn-type-defaults #-} import Data.Text.Lazy as LT default (LT.Text)
- type ShIO a = ReaderT (IORef State) IO a
- shelly :: MonadIO m => ShIO a -> m a
- sub :: ShIO a -> ShIO a
- silently :: ShIO a -> ShIO a
- verbosely :: ShIO a -> ShIO a
- escaping :: Bool -> ShIO a -> ShIO a
- print_stdout :: Bool -> ShIO a -> ShIO a
- print_commands :: Bool -> ShIO a -> ShIO a
- run :: FilePath -> [Text] -> ShIO Text
- run_ :: FilePath -> [Text] -> ShIO ()
- cmd :: ShellCommand result => FilePath -> result
- (-|-) :: ShIO Text -> ShIO b -> ShIO b
- lastStderr :: ShIO Text
- setStdin :: Text -> ShIO ()
- command :: FilePath -> [Text] -> [Text] -> ShIO Text
- command_ :: FilePath -> [Text] -> [Text] -> ShIO ()
- command1 :: FilePath -> [Text] -> Text -> [Text] -> ShIO Text
- command1_ :: FilePath -> [Text] -> Text -> [Text] -> ShIO ()
- sshPairs :: Text -> [(FilePath, [Text])] -> ShIO Text
- sshPairs_ :: Text -> [(FilePath, [Text])] -> ShIO ()
- setenv :: Text -> Text -> ShIO ()
- getenv :: Text -> ShIO Text
- getenv_def :: Text -> Text -> ShIO Text
- appendToPath :: FilePath -> ShIO ()
- cd :: FilePath -> ShIO ()
- chdir :: FilePath -> ShIO a -> ShIO a
- pwd :: ShIO FilePath
- echo, echo_n_err, echo_err, echo_n :: Text -> ShIO ()
- inspect :: Show s => s -> ShIO ()
- inspect_err :: Show s => s -> ShIO ()
- tag :: ShIO a -> Text -> ShIO a
- trace :: Text -> ShIO ()
- show_command :: FilePath -> [Text] -> Text
- ls :: FilePath -> ShIO [FilePath]
- ls' :: FilePath -> ShIO [Text]
- test_e :: FilePath -> ShIO Bool
- test_f :: FilePath -> ShIO Bool
- test_d :: FilePath -> ShIO Bool
- test_s :: FilePath -> ShIO Bool
- which :: FilePath -> ShIO (Maybe FilePath)
- find :: FilePath -> ShIO [FilePath]
- findWhen :: FilePath -> (FilePath -> ShIO Bool) -> ShIO [FilePath]
- findFold :: FilePath -> a -> (a -> FilePath -> ShIO a) -> ShIO a
- findDirFilter :: FilePath -> (FilePath -> ShIO Bool) -> ShIO [FilePath]
- findDirFilterWhen :: FilePath -> (FilePath -> ShIO Bool) -> (FilePath -> ShIO Bool) -> ShIO [FilePath]
- findFoldDirFilter :: FilePath -> (FilePath -> ShIO Bool) -> a -> (a -> FilePath -> ShIO a) -> ShIO a
- path :: FilePath -> ShIO FilePath
- absPath :: FilePath -> ShIO FilePath
- (</>) :: (ToFilePath filepath1, ToFilePath filepath2) => filepath1 -> filepath2 -> FilePath
- (<.>) :: ToFilePath filepath => filepath -> Text -> FilePath
- relativeTo :: FilePath -> FilePath -> ShIO FilePath
- canonic :: FilePath -> ShIO FilePath
- mv :: FilePath -> FilePath -> ShIO ()
- rm :: FilePath -> ShIO ()
- rm_f :: FilePath -> ShIO ()
- rm_rf :: FilePath -> ShIO ()
- cp :: FilePath -> FilePath -> ShIO ()
- cp_r :: FilePath -> FilePath -> ShIO ()
- mkdir :: FilePath -> ShIO ()
- mkdir_p :: FilePath -> ShIO ()
- readfile :: FilePath -> ShIO Text
- writefile :: FilePath -> Text -> ShIO ()
- appendfile :: FilePath -> Text -> ShIO ()
- withTmpDir :: (FilePath -> ShIO a) -> ShIO a
- exit :: Int -> ShIO ()
- errorExit :: Text -> ShIO ()
- terror :: Text -> ShIO a
- (<$>) :: Functor f => (a -> b) -> f a -> f b
- (<$$>) :: Functor m => (b -> c) -> (a -> m b) -> a -> m c
- grep :: PredicateLike pattern hay => pattern -> [hay] -> [hay]
- whenM :: Monad m => m Bool -> m () -> m ()
- unlessM :: Monad m => m Bool -> m () -> m ()
- catchany :: IO a -> (SomeException -> IO a) -> IO a
- catch_sh :: Exception e => ShIO a -> (e -> ShIO a) -> ShIO a
- data ShellyHandler a = forall e . Exception e => ShellyHandler (e -> ShIO a)
- catches_sh :: ShIO a -> [ShellyHandler a] -> ShIO a
- catchany_sh :: ShIO a -> (SomeException -> ShIO a) -> ShIO a
- data Timing = Timing Double
- time :: ShIO a -> ShIO (Timing, a)
- data RunFailed = RunFailed FilePath [Text] Int Text
- toTextIgnore :: FilePath -> Text
- toTextWarn :: FilePath -> ShIO Text
- fromText :: Text -> FilePath
- liftIO :: MonadIO m => forall a. IO a -> m a
- when :: Monad m => Bool -> m () -> m ()
- unless :: Monad m => Bool -> m () -> m ()
- data FilePath
- get :: ShIO State
- put :: State -> ShIO ()
Entering ShIO.
shelly :: MonadIO m => ShIO a -> m aSource
Enter a ShIO from (Monad)IO. The environment and working directories are inherited from the current process-wide values. Any subsequent changes in processwide working directory or environment are not reflected in the running ShIO.
Enter a sub-ShIO that inherits the environment The original state will be restored when the sub-ShIO completes. Exceptions are propagated normally.
silently :: ShIO a -> ShIO aSource
Create a sub-ShIO in which external command outputs are not echoed. Also commands are not printed. See sub.
verbosely :: ShIO a -> ShIO aSource
Create a sub-ShIO in which external command outputs are echoed. Executed commands are printed See sub.
print_stdout :: Bool -> ShIO a -> ShIO aSource
Turn on/off printing stdout
print_commands :: Bool -> ShIO a -> ShIO aSource
Turn on/off command echoing.
Running external commands.
run :: FilePath -> [Text] -> ShIO TextSource
Execute an external command. Takes the command name (no shell allowed,
just a name of something that can be found via PATH
; FIXME: setenv'd
PATH
is not taken into account when finding the exe name)
stdout and stderr are collected. The stdout is returned as a result of run, and complete stderr output is available after the fact using lastStderr
All of the stdout output will be loaded into memory You can avoid this but still consume the result by using run_, If you want to avoid the memory and need to process the output then use runFoldLines.
cmd :: ShellCommand result => FilePath -> resultSource
variadic argument version of run.
The syntax is more convenient but it also allows the use of a FilePath as a command argument.
So an argument can be a Text or a FilePath.
a FilePath is converted to Text with toTextIgnore
.
You will need to add the following to your module:
{-# LANGUAGE OverloadedStrings #-} {-# LANGUAGE ExtendedDefaultRules #-} {-# OPTIONS_GHC -fno-warn-type-defaults #-} import Shelly import Data.Text.Lazy as LT default (LT.Text)
(-|-) :: ShIO Text -> ShIO b -> ShIO bSource
Pipe operator. set the stdout the first command as the stdin of the second.
The output of last external command. See run.
sshPairs :: Text -> [(FilePath, [Text])] -> ShIO TextSource
run commands over SSH.
An ssh executable is expected in your path.
Commands are in the same form as run
, but given as pairs
sshPairs "server-name" [("cd", "dir"), ("rm",["-r","dir2"])]
I am not fond of this interface, but it seems to work.
Please note this sets escaping
to False: the commands will not be shell escaped.
I think this should be more convenient for ssh.
Internally the list of commands are combined with the string && before given to ssh.
Modifying and querying environment.
setenv :: Text -> Text -> ShIO ()Source
Set an environment variable. The environment is maintained in ShIO internally, and is passed to any external commands to be executed.
getenv :: Text -> ShIO TextSource
Fetch the current value of an environment variable. Both empty and non-existent variables give empty string as a result.
getenv_def :: Text -> Text -> ShIO TextSource
Fetch the current value of an environment variable. Both empty and non-existent variables give the default value as a result
appendToPath :: FilePath -> ShIO ()Source
add the filepath onto the PATH env variable
FIXME: only effects the PATH once the process is ran, as per comments in which
Environment directory
cd :: FilePath -> ShIO ()Source
Change current working directory of ShIO. This does *not* change the working directory of the process we are running it. Instead, ShIO keeps track of its own workking directory and builds absolute paths internally instead of passing down relative paths. This may have performance repercussions if you are doing hundreds of thousands of filesystem operations. You will want to handle these issues differently in those cases.
chdir :: FilePath -> ShIO a -> ShIO aSource
cd, execute a ShIO action in the new directory and then pop back to the original directory
Printing
echo, echo_n_err, echo_err, echo_n :: Text -> ShIO ()Source
Echo text to standard (error, when using _err variants) output. The _n variants do not print a final newline.
inspect_err :: Show s => s -> ShIO ()Source
a print lifted into ShIO using stderr
show_command :: FilePath -> [Text] -> TextSource
Querying filesystem.
ls :: FilePath -> ShIO [FilePath]Source
List directory contents. Does *not* include "." and "..", but it does include (other) hidden files.
which :: FilePath -> ShIO (Maybe FilePath)Source
Get a full path to an executable on PATH
, if exists. FIXME does not
respect setenv'd environment and uses findExecutable
which uses the PATH
inherited from the process
environment.
FIXME: findExecutable does not maintain a hash of existing commands and does a ton of file stats
Finding files
find :: FilePath -> ShIO [FilePath]Source
List directory recursively (like the POSIX utility find). listing is relative if the path given is relative. If you want to filter out some results or fold over them you can do that with the returned files. A more efficient approach is to use one of the other find functions.
findWhen :: FilePath -> (FilePath -> ShIO Bool) -> ShIO [FilePath]Source
find
that filters the found files as it finds.
Files must satisfy the given filter to be returned in the result.
findDirFilter :: FilePath -> (FilePath -> ShIO Bool) -> ShIO [FilePath]Source
find
that filters out directories as it finds
Filtering out directories can make a find much more efficient by avoiding entire trees of files.
:: FilePath | directory |
-> (FilePath -> ShIO Bool) | directory filter |
-> (FilePath -> ShIO Bool) | file filter |
-> ShIO [FilePath] |
similar findWhen
, but also filter out directories
Alternatively, similar to findDirFilter
, but also filter out files
Filtering out directories makes the find much more efficient
findFoldDirFilter :: FilePath -> (FilePath -> ShIO Bool) -> a -> (a -> FilePath -> ShIO a) -> ShIO aSource
like findDirFilterWhen
but use a folding function rather than a filter
The most general finder: you likely want a more specific one
Filename helpers
absPath :: FilePath -> ShIO FilePathSource
makes an absolute path based on the working directory.
path
will also canonicalize
(</>) :: (ToFilePath filepath1, ToFilePath filepath2) => filepath1 -> filepath2 -> FilePathSource
uses System.FilePath.CurrentOS, but can automatically convert a Text
(<.>) :: ToFilePath filepath => filepath -> Text -> FilePathSource
uses System.FilePath.CurrentOS, but can automatically convert a Text
make the second path relative to the first
Uses stripPrefix
, but will canonicalize the paths if necessary
canonic :: FilePath -> ShIO FilePathSource
Obtain a (reasonably) canonic file path to a filesystem object. Based on canonicalizePath in FileSystem.
Manipulating filesystem.
mv :: FilePath -> FilePath -> ShIO ()Source
Currently a renameFile wrapper. TODO: Support cross-filesystem move. TODO: Support directory paths in the second parameter, like in cp.
rm :: FilePath -> ShIO ()Source
Remove a file.
Does fail if the file does not exist (use rm_f
instead) or is not a file.
rm_f :: FilePath -> ShIO ()Source
Remove a file. Does not fail if the file already is not there. Does fail if the file is not a file.
rm_rf :: FilePath -> ShIO ()Source
A swiss army cannon for removing things. Actually this goes farther than a
normal rm -rf, as it will circumvent permission problems for the files we
own. Use carefully.
Uses removeTree
cp :: FilePath -> FilePath -> ShIO ()Source
Copy a file. The second path could be a directory, in which case the original file name is used, in that directory.
mkdir_p :: FilePath -> ShIO ()Source
Create a new directory, including parents (succeeds if the directory already exists).
readfile :: FilePath -> ShIO TextSource
(Strictly) read file into a Text. All other functions use Lazy Text. So Internally this reads a file as strict text and then converts it to lazy text, which is inefficient
withTmpDir :: (FilePath -> ShIO a) -> ShIO aSource
Create a temporary directory and pass it as a parameter to a ShIO computation. The directory is nuked afterwards.
exiting the program
Utilities.
(<$$>) :: Functor m => (b -> c) -> (a -> m b) -> a -> m cSource
A functor-lifting function composition.
grep :: PredicateLike pattern hay => pattern -> [hay] -> [hay]Source
Like filter, but more conveniently used with String lists, where a
substring match (TODO: also provide globs) is expressed as
grep "needle" [ "the", "stack", "of", "hay" ]
. Boolean
predicates just like with filter are supported too:
grep ("fun"
.
isPrefixOf
) [...]
unlessM :: Monad m => m Bool -> m () -> m ()Source
A monadic-conditional version of the unless guard.
catchany :: IO a -> (SomeException -> IO a) -> IO aSource
A helper to catch any exception (same as
...
).
catch
(e :: SomeException) -> ...
catch_sh :: Exception e => ShIO a -> (e -> ShIO a) -> ShIO aSource
Catch an exception in the ShIO monad.
data ShellyHandler a Source
You need this when using catches_sh
.
forall e . Exception e => ShellyHandler (e -> ShIO a) |
catches_sh :: ShIO a -> [ShellyHandler a] -> ShIO aSource
Catch multiple exceptions in the ShIO monad.
catchany_sh :: ShIO a -> (SomeException -> ShIO a) -> ShIO aSource
Catch an exception in the ShIO monad.
convert between Text and FilePath
toTextIgnore :: FilePath -> TextSource
silently uses the Right or Left value of Filesystem.Path.CurrentOS.toText
toTextWarn :: FilePath -> ShIO TextSource
Re-exported for your convenience
when :: Monad m => Bool -> m () -> m ()
Conditional execution of monadic expressions. For example,
when debug (putStr "Debugging\n")
will output the string Debugging\n
if the Boolean value debug
is True
,
and otherwise do nothing.
data FilePath