Lua: add function pandoc.utils.run_lua_filter

pandoc-lua-engine/pandoc-lua-engine.cabal

@@ -67,6 +67,7 @@ library
  hs-source-dirs: src
  exposed-modules: Text.Pandoc.Lua
  other-modules: Text.Pandoc.Lua.Custom
+ , Text.Pandoc.Lua.Engine
  , Text.Pandoc.Lua.Filter
  , Text.Pandoc.Lua.Global
  , Text.Pandoc.Lua.Init

pandoc-lua-engine/src/Text/Pandoc/Lua.hs

@@ -23,26 +23,8 @@ module Text.Pandoc.Lua
  , getEngine
  ) where
 
-import Control.Monad.IO.Class (MonadIO (liftIO))
-import HsLua.Core (getglobal, openlibs, run, top, tostring)
-import Text.Pandoc.Error (PandocError)
-import Text.Pandoc.Lua.Filter (applyFilter)
+import Text.Pandoc.Lua.Engine (getEngine, applyFilter)
 import Text.Pandoc.Lua.Global (Global (..), setGlobals)
 import Text.Pandoc.Lua.Init (runLua, runLuaNoEnv)
 import Text.Pandoc.Lua.Custom (loadCustom)
 import Text.Pandoc.Lua.Orphans ()
-import Text.Pandoc.Scripting (ScriptingEngine (..))
-import qualified Text.Pandoc.UTF8 as UTF8
-
--- | Constructs the Lua scripting engine.
-getEngine :: MonadIO m => m ScriptingEngine
-getEngine = do
- versionName <- liftIO . run @PandocError $ do
- openlibs
- getglobal "_VERSION"
- tostring top
- pure $ ScriptingEngine
- { engineName = maybe "Lua (unknown version)" UTF8.toText versionName
- , engineApplyFilter = applyFilter
- , engineLoadCustom = loadCustom
- }

pandoc-lua-engine/src/Text/Pandoc/Lua/Engine.hs

@@ -0,0 +1,73 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE TypeApplications #-}
+{- |
+ Module : Text.Pandoc.Lua.Engine
+ Copyright : Copyright © 2017-2024 Albert Krewinkel
+ License : GPL-2.0-or-later
+ Maintainer : Albert Krewinkel <tarleb+pandoc@zeitkraut.de>
+
+Running pandoc Lua filters.
+-}
+module Text.Pandoc.Lua.Engine
+ ( getEngine
+ , applyFilter
+ ) where
+
+import Control.Exception (throw)
+import Control.Monad ((>=>))
+import Control.Monad.IO.Class (MonadIO (liftIO))
+import HsLua.Core (getglobal, openlibs, run, top, tostring)
+import Text.Pandoc.Class (PandocMonad)
+import Text.Pandoc.Definition (Pandoc)
+import Text.Pandoc.Filter (Environment (..))
+import Text.Pandoc.Error (PandocError (PandocFilterError, PandocLuaError))
+import Text.Pandoc.Lua.Filter (runFilterFile)
+import Text.Pandoc.Lua.Global (Global (..), setGlobals)
+import Text.Pandoc.Lua.Init (runLua)
+import Text.Pandoc.Lua.Custom (loadCustom)
+import Text.Pandoc.Lua.Orphans ()
+import Text.Pandoc.Scripting (ScriptingEngine (..))
+import qualified Text.Pandoc.UTF8 as UTF8
+import qualified Data.Text as T
+
+-- | Constructs the Lua scripting engine.
+getEngine :: MonadIO m => m ScriptingEngine
+getEngine = do
+ versionName <- liftIO . run @PandocError $ do
+ openlibs
+ getglobal "_VERSION"
+ tostring top
+ pure $ ScriptingEngine
+ { engineName = maybe "Lua (unknown version)" UTF8.toText versionName
+ , engineApplyFilter = applyFilter
+ , engineLoadCustom = loadCustom
+ }
+
+-- | Run the Lua filter in @filterPath@ for a transformation to the
+-- target format (first element in args). Pandoc uses Lua init files to
+-- setup the Lua interpreter.
+applyFilter :: (PandocMonad m, MonadIO m)
+ => Environment
+ -> [String]
+ -> FilePath
+ -> Pandoc
+ -> m Pandoc
+applyFilter fenv args fp doc = do
+ let globals = [ FORMAT $ case args of
+ x:_ -> T.pack x
+ _ -> ""
+ , PANDOC_READER_OPTIONS (envReaderOptions fenv)
+ , PANDOC_WRITER_OPTIONS (envWriterOptions fenv)
+ , PANDOC_SCRIPT_FILE fp
+ ]
+ runLua >=> forceResult fp $ do
+ setGlobals globals
+ runFilterFile fp doc
+
+forceResult :: (PandocMonad m, MonadIO m)
+ => FilePath -> Either PandocError Pandoc -> m Pandoc
+forceResult fp eitherResult = case eitherResult of
+ Right x -> return x
+ Left err -> throw . PandocFilterError (T.pack fp) $ case err of
+ PandocLuaError msg -> msg
+ _ -> T.pack $ show err

pandoc-lua-engine/src/Text/Pandoc/Lua/Filter.hs

@@ -1,6 +1,5 @@
 {-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE IncoherentInstances #-}
-{-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {- |
 Module : Text.Pandoc.Lua.Filter
@@ -13,29 +12,22 @@ Stability : alpha
 Types and functions for running Lua filters.
 -}
 module Text.Pandoc.Lua.Filter
- ( applyFilter
+ ( runFilterFile
  ) where
 import Control.Monad ((>=>), (<$!>))
-import HsLua as Lua
-import Text.Pandoc.Definition
-import Text.Pandoc.Filter (Environment (..))
+import HsLua
+import Text.Pandoc.Definition (Pandoc)
+import Text.Pandoc.Error (PandocError)
 import Text.Pandoc.Lua.Marshal.AST
 import Text.Pandoc.Lua.Marshal.Filter
-import Text.Pandoc.Lua.Global (Global (..), setGlobals)
-import Text.Pandoc.Lua.Init (runLua)
 import Text.Pandoc.Lua.PandocLua ()
-import Control.Exception (throw)
-import qualified Data.Text as T
-import Text.Pandoc.Class (PandocMonad)
-import Control.Monad.Trans (MonadIO)
-import Text.Pandoc.Error (PandocError (PandocFilterError, PandocLuaError))
 
 -- | Transform document using the filter defined in the given file.
 runFilterFile :: FilePath -> Pandoc -> LuaE PandocError Pandoc
 runFilterFile filterPath doc = do
  oldtop <- gettop
  stat <- dofileTrace (Just filterPath)
- if stat /= Lua.OK
+ if stat /= OK
  then throwErrorAsException
  else do
  newtop <- gettop
@@ -50,32 +42,3 @@ runFilterFile filterPath doc = do
 
 runAll :: [Filter] -> Pandoc -> LuaE PandocError Pandoc
 runAll = foldr ((>=>) . applyFully) return
-
--- | Run the Lua filter in @filterPath@ for a transformation to the
--- target format (first element in args). Pandoc uses Lua init files to
--- setup the Lua interpreter.
-applyFilter :: (PandocMonad m, MonadIO m)
- => Environment
- -> [String]
- -> FilePath
- -> Pandoc
- -> m Pandoc
-applyFilter fenv args fp doc = do
- let globals = [ FORMAT $ case args of
- x:_ -> T.pack x
- _ -> ""
- , PANDOC_READER_OPTIONS (envReaderOptions fenv)
- , PANDOC_WRITER_OPTIONS (envWriterOptions fenv)
- , PANDOC_SCRIPT_FILE fp
- ]
- runLua >=> forceResult fp $ do
- setGlobals globals
- runFilterFile fp doc
-
-forceResult :: (PandocMonad m, MonadIO m)
- => FilePath -> Either PandocError Pandoc -> m Pandoc
-forceResult fp eitherResult = case eitherResult of
- Right x -> return x
- Left err -> throw . PandocFilterError (T.pack fp) $ case err of
- PandocLuaError msg -> msg
- _ -> T.pack $ show err

pandoc-lua-engine/src/Text/Pandoc/Lua/Module/Utils.hs

@@ -29,6 +29,7 @@ import Text.Pandoc.Citeproc (getReferences, processCitations)
 import Text.Pandoc.Definition
 import Text.Pandoc.Error (PandocError)
 import Text.Pandoc.Filter (applyJSONFilter)
+import Text.Pandoc.Lua.Filter (runFilterFile)
 import Text.Pandoc.Lua.Marshal.AST
 import Text.Pandoc.Lua.Marshal.Reference
 import Text.Pandoc.Lua.PandocLua (PandocLua (unPandocLua))
@@ -60,6 +61,7 @@ documentedModule = Module
  , from_simple_table `since` v[2,11]
  , make_sections `since` v[2,8]
  , references `since` v[2,17]
+ , run_lua_filter `since` v[3,2,1]
  , run_json_filter `since` v[2,1,1]
  , normalize_date `since` v[2,0,6]
  , sha1 `since` v[2,0,6]
@@ -246,6 +248,18 @@ references = defun "references"
  , " end"
  ]
 
+-- | Run a filter from a file.
+run_lua_filter :: DocumentedFunction PandocError
+run_lua_filter = defun "run_filter_filter"
+ ### (flip runFilterFile)
+ <#> parameter peekPandoc "Pandoc" "doc" "the Pandoc document to filter"
+ <#> parameter peekString "string" "filter" "filepath of the filter to run"
+ =#> functionResult pushPandoc "Pandoc" "filtered document"
+ #? ( "Filter the given doc by passing it through a Lua filter." <>
+ "\n\nThe filter will be run in the current Lua process."
+ )
+
+-- | Process the document with a JSON filter.
 run_json_filter :: DocumentedFunction PandocError
 run_json_filter = defun "run_json_filter"
  ### (\doc filterPath margs -> do