From 2677e8466311e2becdd7f65f1f6c23d559db14aa Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Thu, 8 Aug 2013 11:09:00 -0700
Subject: [PATCH] Revert "Revert "Added `--filter` option.""
This reverts commit 2e5edbb27837372f658b1abbe05371be57415847.
---
README | 8 ++++++++
pandoc.cabal | 1 +
pandoc.hs | 25 +++++++++++++++++++++----
3 files changed, 30 insertions(+), 4 deletions(-)
diff --git a/README b/README
index bc5d5619d..e85ca1905 100644
--- a/README
+++ b/README
@@ -259,6 +259,14 @@ Reader options
require different kinds of images. Currently this option only affects
the markdown and LaTeX readers.
+`--filter=`*PATH*
+: Specify an executable to be used as a filter transforming the
+ Pandoc AST after the input is parsed and before the output is
+ written. The executable should read JSON from stdin and write
+ JSON to stdout. The JSON must be formatted like pandoc's own
+ JSON input and output. Filters may be most easily created in Haskell,
+ using the utility function `toJsonFilter` from `Text.Pandoc`.
+
`--normalize`
: Normalize the document after reading: merge adjacent
`Str` or `Emph` elements, for example, and remove repeated `Space`s.
diff --git a/pandoc.cabal b/pandoc.cabal
index 19f8c14ef..a8dd528ad 100644
--- a/pandoc.cabal
+++ b/pandoc.cabal
@@ -352,6 +352,7 @@ Executable pandoc
extensible-exceptions >= 0.1 && < 0.2,
highlighting-kate >= 0.5.5 && < 0.6,
HTTP >= 4000.0.5 && < 4000.3,
+ process >= 1 && < 1.2,
citeproc-hs >= 0.3.7 && < 0.4
Ghc-Options: -rtsopts -with-rtsopts=-K16m -Wall -fno-warn-unused-do-bind
Ghc-Prof-Options: -auto-all -caf-all -rtsopts -with-rtsopts=-K16m
diff --git a/pandoc.hs b/pandoc.hs
index 79bade221..94d206103 100644
--- a/pandoc.hs
+++ b/pandoc.hs
@@ -43,6 +43,7 @@ import System.Environment ( getArgs, getProgName )
import System.Exit ( exitWith, ExitCode (..) )
import System.FilePath
import System.Console.GetOpt
+import System.Process (readProcess)
import Data.Char ( toLower )
import Data.List ( intercalate, isPrefixOf, sort )
import System.Directory ( getAppUserDataDirectory, doesFileExist, findExecutable )
@@ -53,6 +54,7 @@ import Control.Exception.Extensible ( throwIO )
import qualified Text.Pandoc.UTF8 as UTF8
import qualified Text.CSL as CSL
import Control.Monad (when, unless, liftM)
+import Data.Foldable (foldrM)
import Network.HTTP (simpleHTTP, mkRequest, getResponseBody, RequestMethod(..))
import Network.URI (parseURI, isURI, URI(..))
import qualified Data.ByteString.Lazy as B
@@ -86,6 +88,12 @@ wrapWords indent c = wrap' (c - indent) (c - indent)
isTextFormat :: String -> Bool
isTextFormat s = takeWhile (`notElem` "+-") s `notElem` ["odt","docx","epub","epub3"]
+externalFilter :: FilePath -> Pandoc -> IO Pandoc
+externalFilter f d = E.catch
+ (readJSON def `fmap` readProcess f [] (writeJSON def d))
+ (\e -> let _ = (e :: E.SomeException)
+ in err 83 $ "Error running filter `" ++ f ++ "'")
+
-- | Data structure for command line options.
data Opt = Opt
{ optTabStop :: Int -- ^ Number of spaces per tab
@@ -272,6 +280,13 @@ options =
"STRING")
"" -- "Classes (whitespace- or comma-separated) to use for indented code-blocks"
+ , Option "" ["filter"]
+ (ReqArg
+ (\arg opt -> return opt { optPlugins = externalFilter arg :
+ optPlugins opt })
+ "PROGRAM")
+ "" -- "External JSON filter"
+
, Option "" ["normalize"]
(NoArg
(\opt -> return opt { optTransforms =
@@ -876,6 +891,7 @@ main = do
, optReferenceLinks = referenceLinks
, optWrapText = wrap
, optColumns = columns
+ , optPlugins = plugins
, optEmailObfuscation = obfuscationMethod
, optIdentifierPrefix = idPrefix
, optIndentedCodeClasses = codeBlockClasses
@@ -1099,6 +1115,7 @@ main = do
reader readerOpts
let doc0 = foldr ($) doc transforms
+ doc1 <- foldrM ($) doc0 plugins
let writeBinary :: B.ByteString -> IO ()
writeBinary = B.writeFile (UTF8.encodePath outputFile)
@@ -1109,15 +1126,15 @@ main = do
case getWriter writerName' of
Left e -> err 9 e
- Right (IOStringWriter f) -> f writerOptions doc0 >>= writerFn outputFile
- Right (IOByteStringWriter f) -> f writerOptions doc0 >>= writeBinary
+ Right (IOStringWriter f) -> f writerOptions doc1 >>= writerFn outputFile
+ Right (IOByteStringWriter f) -> f writerOptions doc1 >>= writeBinary
Right (PureStringWriter f)
| pdfOutput -> do
- res <- makePDF latexEngine f writerOptions doc0
+ res <- makePDF latexEngine f writerOptions doc1
case res of
Right pdf -> writeBinary pdf
Left err' -> err 43 $ UTF8.toStringLazy err'
- | otherwise -> selfcontain (f writerOptions doc0 ++
+ | otherwise -> selfcontain (f writerOptions doc1 ++
['\n' | not standalone'])
>>= writerFn outputFile . handleEntities
where htmlFormat = writerName' `elem`