1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
--------------------------------------------------------------------------------
-- | Wraps pandocs bibiliography handling
--
-- In order to add a bibliography, you will need a bibliography file (e.g.
-- @.bib@) and a CSL file (@.csl@). Both need to be compiled with their
-- respective compilers ('biblioCompiler' and 'cslCompiler'). Then, you can
-- refer to these files when you use 'readPandocBiblio'. This function also
-- takes the reader options for completeness -- you can use
-- 'defaultHakyllReaderOptions' if you're unsure.
-- 'pandocBiblioCompiler' is a convenience wrapper which works like 'pandocCompiler',
-- but also takes paths to compiled bibliography and csl files.
{-# LANGUAGE Arrows #-}
{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE OverloadedStrings #-}
module Hakyll.Web.Pandoc.Biblio
( CSL
, cslCompiler
, Biblio (..)
, biblioCompiler
, readPandocBiblio
, pandocBiblioCompiler
) where
--------------------------------------------------------------------------------
import Control.Monad (liftM)
import Data.Binary (Binary (..))
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy as BL
import qualified Data.Map as Map
import qualified Data.Time as Time
import Data.Typeable (Typeable)
import Hakyll.Core.Compiler
import Hakyll.Core.Compiler.Internal
import Hakyll.Core.Identifier
import Hakyll.Core.Item
import Hakyll.Core.Writable
import Hakyll.Web.Pandoc
import Text.Pandoc (Extension (..), Pandoc,
ReaderOptions (..),
enableExtension)
import qualified Text.Pandoc as Pandoc
import qualified Text.Pandoc.Citeproc as Pandoc (processCitations)
--------------------------------------------------------------------------------
newtype CSL = CSL {unCSL :: B.ByteString}
deriving (Binary, Show, Typeable)
--------------------------------------------------------------------------------
instance Writable CSL where
-- Shouldn't be written.
write _ _ = return ()
--------------------------------------------------------------------------------
cslCompiler :: Compiler (Item CSL)
cslCompiler = fmap (CSL . BL.toStrict) <$> getResourceLBS
--------------------------------------------------------------------------------
newtype Biblio = Biblio {unBiblio :: B.ByteString}
deriving (Binary, Show, Typeable)
--------------------------------------------------------------------------------
instance Writable Biblio where
-- Shouldn't be written.
write _ _ = return ()
--------------------------------------------------------------------------------
biblioCompiler :: Compiler (Item Biblio)
biblioCompiler = fmap (Biblio . BL.toStrict) <$> getResourceLBS
--------------------------------------------------------------------------------
readPandocBiblio :: ReaderOptions
-> Item CSL
-> Item Biblio
-> (Item String)
-> Compiler (Item Pandoc)
readPandocBiblio ropt csl biblio item = do
-- It's not straightforward to use the Pandoc API as of 2.11 to deal with
-- citations, since it doesn't export many things in 'Text.Pandoc.Citeproc'.
-- The 'citeproc' package is also hard to use.
--
-- So instead, we try treating Pandoc as a black box. Pandoc can read
-- specific csl and bilbio files based on metadata keys.
--
-- So we load the CSL and Biblio files and pass them to Pandoc using the
-- ersatz filesystem.
Pandoc.Pandoc (Pandoc.Meta meta) blocks <- itemBody <$>
readPandocWith ropt item
let cslFile = Pandoc.FileInfo zeroTime . unCSL $ itemBody csl
bibFile = Pandoc.FileInfo zeroTime . unBiblio $ itemBody biblio
addBiblioFiles = \st -> st
{ Pandoc.stFiles =
Pandoc.insertInFileTree "_hakyll/style.csl" cslFile .
Pandoc.insertInFileTree "_hakyll/refs.bib" bibFile $
Pandoc.stFiles st
}
biblioMeta = Pandoc.Meta .
Map.insert "csl" (Pandoc.MetaString "_hakyll/style.csl") .
Map.insert "bibliography" (Pandoc.MetaString "_hakyll/refs.bib") $
meta
errOrPandoc = Pandoc.runPure $ do
Pandoc.modifyPureState addBiblioFiles
Pandoc.processCitations $ Pandoc.Pandoc biblioMeta blocks
pandoc <- case errOrPandoc of
Left e -> compilerThrow ["Error during processCitations: " ++ show e]
Right x -> return x
return $ fmap (const pandoc) item
where
zeroTime = Time.UTCTime (toEnum 0) 0
--------------------------------------------------------------------------------
-- | Compiles a markdown file via Pandoc. Requires the .csl and .bib files to be known to the compiler via match statements.
pandocBiblioCompiler :: String -> String -> Compiler (Item String)
pandocBiblioCompiler cslFileName bibFileName = do
csl <- load $ fromFilePath cslFileName
bib <- load $ fromFilePath bibFileName
liftM writePandoc
(getResourceBody >>= readPandocBiblio ropt csl bib)
where ropt = defaultHakyllReaderOptions
{ -- The following option enables citation rendering
readerExtensions = enableExtension Ext_citations $ readerExtensions defaultHakyllReaderOptions
}
|
