Text.Pandoc.App: ToJSON and FromJSON instances for Opts.

This can be used e.g. to pass options via web interface,
such as trypandoc.

3 files changed, 66 insertions, 5 deletions

diff --git a/src/Text/Pandoc/App.hs b/src/Text/Pandoc/App.hs
index c874a2cde..eee72fd3c 100644
--- a/src/Text/Pandoc/App.hs
+++ b/src/Text/Pandoc/App.hs
@@ -1,6 +1,7 @@
 {-# LANGUAGE CPP                 #-}
 {-# LANGUAGE ScopedTypeVariables #-}
 {-# LANGUAGE TupleSections       #-}
+{-# LANGUAGE DeriveGeneric       #-}
 {-
 Copyright (C) 2006-2017 John MacFarlane <jgm@berkeley.edu>
 
@@ -42,12 +43,14 @@ import qualified Control.Exception as E
 import Control.Monad.Except (throwError)
 import Control.Monad
 import Control.Monad.Trans
-import Data.Aeson (eitherDecode', encode)
+import Data.Aeson (eitherDecode', encode, ToJSON(..), FromJSON(..),
+                   genericToEncoding, defaultOptions)
 import qualified Data.ByteString as BS
 import qualified Data.ByteString.Lazy as B
 import Data.Char (toLower, toUpper)
 import qualified Data.Set as Set
 import Data.Foldable (foldrM)
+import GHC.Generics
 import Data.List (intercalate, isPrefixOf, isSuffixOf, sort)
 import qualified Data.Map as M
 import Data.Maybe (fromMaybe, isJust, isNothing)
@@ -65,7 +68,8 @@ import System.Directory (Permissions (..), doesFileExist, findExecutable,
 import System.Environment (getArgs, getEnvironment, getProgName)
 import System.Exit (ExitCode (..), exitSuccess)
 import System.FilePath
-import System.IO (stdout, nativeNewline, Newline(..))
+import System.IO (stdout, nativeNewline)
+import qualified System.IO as IO (Newline(..))
 import System.IO.Error (isDoesNotExistError)
 import Text.Pandoc
 import Text.Pandoc.Builder (setMeta)
@@ -86,6 +90,12 @@ import System.Posix.IO (stdOutput)
 import System.Posix.Terminal (queryTerminal)
 #endif
 
+data Newline = LF | CRLF deriving (Show, Generic)
+
+instance ToJSON Newline where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON Newline
+
 parseOptions :: [OptDescr (Opt -> IO Opt)] -> Opt -> IO Opt
 parseOptions options' defaults = do
   rawArgs <- map UTF8.decodeArg <$> getArgs
@@ -411,7 +421,10 @@ convertWithOpts opts = do
                    return $ ("csl", jatsEncoded) : optMetadata opts
                  else return $ optMetadata opts
 
-  let eol = fromMaybe nativeNewline $ optEol opts
+  let eol = case optEol opts of
+                 Just CRLF -> IO.CRLF
+                 Just LF   -> IO.LF
+                 Nothing   -> nativeNewline
 
   runIO' $ do
     setResourcePath (optResourcePath opts)
@@ -572,7 +585,11 @@ data Opt = Opt
     , optIncludeInHeader       :: [FilePath]       -- ^ Files to include in header
     , optResourcePath          :: [FilePath] -- ^ Path to search for images etc
     , optEol                   :: Maybe Newline    -- ^ Enforce line-endings
-    }
+    } deriving (Generic, Show)
+
+instance ToJSON Opt where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON Opt
 
 -- | Defaults for command-line options.
 defaultOpts :: Opt
@@ -790,7 +807,7 @@ writeFnBinary :: MonadIO m => FilePath -> B.ByteString -> m ()
 writeFnBinary "-" = liftIO . B.putStr
 writeFnBinary f   = liftIO . B.writeFile (UTF8.encodePath f)
 
-writerFn :: MonadIO m => Newline -> FilePath -> String -> m ()
+writerFn :: MonadIO m => IO.Newline -> FilePath -> String -> m ()
 writerFn eol "-" = liftIO . UTF8.putStrWith eol
 writerFn eol f   = liftIO . UTF8.writeFileWith eol f
 
diff --git a/src/Text/Pandoc/Logging.hs b/src/Text/Pandoc/Logging.hs
index 2cca4b7d3..bf7f33d29 100644
--- a/src/Text/Pandoc/Logging.hs
+++ b/src/Text/Pandoc/Logging.hs
@@ -39,6 +39,7 @@ module Text.Pandoc.Logging (
   , messageVerbosity
   ) where
 
+import Control.Monad (mzero)
 import Data.Aeson
 import Data.Aeson.Encode.Pretty (Config (..), defConfig, encodePretty',
                                  keyOrder)
@@ -56,6 +57,15 @@ data Verbosity = ERROR | WARNING | INFO | DEBUG
 
 instance ToJSON Verbosity where
   toJSON x = toJSON (show x)
+instance FromJSON Verbosity where
+  parseJSON (String t) =
+    case t of
+         "ERROR"   -> return ERROR
+         "WARNING" -> return WARNING
+         "INFO"    -> return INFO
+         "DEBUG"   -> return DEBUG
+         _         -> mzero
+  parseJSON _      =  mzero
 
 data LogMessage =
     SkippedContent String SourcePos
diff --git a/src/Text/Pandoc/Options.hs b/src/Text/Pandoc/Options.hs
index 6757c6782..c7211c86e 100644
--- a/src/Text/Pandoc/Options.hs
+++ b/src/Text/Pandoc/Options.hs
@@ -45,6 +45,8 @@ module Text.Pandoc.Options ( module Text.Pandoc.Extensions
                            , def
                            , isEnabled
                            ) where
+import Data.Aeson (ToJSON(..), FromJSON(..),
+                   genericToEncoding, defaultOptions)
 import Data.Data (Data)
 import Data.Default
 import qualified Data.Set as Set
@@ -104,17 +106,29 @@ data HTMLMathMethod = PlainMath
                     | KaTeX String String -- url of stylesheet and katex.js
                     deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON HTMLMathMethod where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON HTMLMathMethod
+
 data CiteMethod = Citeproc                        -- use citeproc to render them
                   | Natbib                        -- output natbib cite commands
                   | Biblatex                      -- output biblatex cite commands
                 deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON CiteMethod where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CiteMethod
+
 -- | Methods for obfuscating email addresses in HTML.
 data ObfuscationMethod = NoObfuscation
                        | ReferenceObfuscation
                        | JavascriptObfuscation
                        deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON ObfuscationMethod where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ObfuscationMethod
+
 -- | Varieties of HTML slide shows.
 data HTMLSlideVariant = S5Slides
                       | SlidySlides
@@ -124,18 +138,30 @@ data HTMLSlideVariant = S5Slides
                       | NoSlides
                       deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON HTMLSlideVariant where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON HTMLSlideVariant
+
 -- | Options for accepting or rejecting MS Word track-changes.
 data TrackChanges = AcceptChanges
                   | RejectChanges
                   | AllChanges
                   deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON TrackChanges where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON TrackChanges
+
 -- | Options for wrapping text in the output.
 data WrapOption = WrapAuto        -- ^ Automatically wrap to width
                 | WrapNone        -- ^ No non-semantic newlines
                 | WrapPreserve    -- ^ Preserve wrapping of input source
                 deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON WrapOption where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON WrapOption
+
 -- | Options defining the type of top-level headers.
 data TopLevelDivision = TopLevelPart      -- ^ Top-level headers become parts
                       | TopLevelChapter   -- ^ Top-level headers become chapters
@@ -144,12 +170,20 @@ data TopLevelDivision = TopLevelPart      -- ^ Top-level headers become parts
                                           --   heuristics
                       deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON TopLevelDivision where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON TopLevelDivision
+
 -- | Locations for footnotes and references in markdown output
 data ReferenceLocation = EndOfBlock    -- ^ End of block
                        | EndOfSection  -- ^ prior to next section header (or end of document)
                        | EndOfDocument -- ^ at end of document
                        deriving (Show, Read, Eq, Data, Typeable, Generic)
 
+instance ToJSON ReferenceLocation where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ReferenceLocation
+
 -- | Options for writers
 data WriterOptions = WriterOptions
   { writerTemplate          :: Maybe String -- ^ Template to use