path: root/www/hs-gitit/files/extra-patch-exports

diff --git README.markdown README.markdown
index d49e0cc..c5a4ada 100644
--- README.markdown
+++ README.markdown
@@ -7,9 +7,10 @@ files are stored in a [git], [darcs], or [mercurial] repository
 and may be modified either by using the VCS's command-line tools or
 through the wiki's web interface. By default, pandoc's extended version
 of markdown is used as a markup language, but reStructuredText, LaTeX, HTML,
-DocBook, or Emacs Org-mode markup can also be used.  Gitit can
-be configured to display TeX math (using [texmath]) and
-highlighted source code (using [highlighting-kate]).
+DocBook, or Emacs Org-mode markup can also be used. Pages can be exported in a
+number of different formats, including LaTeX, RTF, OpenOffice ODT, and
+MediaWiki markup.  Gitit can be configured to display TeX math (using
+[texmath]) and highlighted source code (using [highlighting-kate]).
 
 Other features include
 
@@ -410,7 +411,7 @@ Caching
 By default, gitit does not cache content.  If your wiki receives a lot of
 traffic or contains pages that are slow to render, you may want to activate
 caching.  To do this, set the configuration option `use-cache` to `yes`.
-By default, rendered pages, and highlighted source files
+By default, rendered pages, highlighted source files, and exported PDFs
 will be cached in the `cache` directory. (Another directory can be
 specified by setting the `cache-dir` configuration option.)
 
diff --git data/default.conf data/default.conf
index cd528f9..567bf8f 100644
--- data/default.conf
+++ data/default.conf
@@ -266,9 +266,16 @@ feed-days: 14
 feed-refresh-time: 60
 # number of minutes to cache feeds before refreshing
 
+pdf-export: no
+# if yes, PDF will appear in export options. PDF will be created using
+# pdflatex, which must be installed and in the path. Note that PDF
+# exports create significant additional server load.
+
 pandoc-user-data:
 # if a directory is specified, this will be searched for pandoc
-# customizations.  If no directory is
+# customizations. These can include a templates/ directory for custom
+# templates for various export formats, an S5 directory for custom
+# S5 styles, and a reference.odt for ODT exports. If no directory is
 # specified, $HOME/.pandoc will be searched. See pandoc's README for
 # more information.
 
diff --git data/templates/pagetools.st data/templates/pagetools.st
index a5178f4..2d01dfa 100644
--- data/templates/pagetools.st
+++ data/templates/pagetools.st
@@ -9,5 +9,6 @@
       <li><a href="$base$/_feed$pageUrl$" type="application/atom+xml" rel="alternate" title="This page's ATOM Feed">Atom feed</a> <img alt="feed icon" src="$base$/img/icons/feed.png"/></li>
       $endif$
     </ul>
+    $exportbox$
   </fieldset>
 </div>
diff --git gitit.cabal gitit.cabal
index 3d0d695..361415d 100644
--- gitit.cabal
+++ gitit.cabal
@@ -115,6 +115,7 @@ Library
                      Network.Gitit.Authentication.Github,
                      Network.Gitit.Util, Network.Gitit.Server
                      Network.Gitit.Cache, Network.Gitit.State,
+                     Network.Gitit.Export,
                      Network.Gitit.Handlers,
                      Network.Gitit.Plugins, Network.Gitit.Rpxnow,
                      Network.Gitit.Page, Network.Gitit.Feed,
diff --git src/Network/Gitit.hs src/Network/Gitit.hs
index 3ad25f8..032cc9d 100644
--- src/Network/Gitit.hs
+++ src/Network/Gitit.hs
@@ -199,6 +199,7 @@ wikiHandlers =
           authenticate ForModify (unlessNoDelete deletePage showPage) ]
   , dir "_preview" preview
   , guardIndex >> indexPage
+  , guardCommand "export" >> exportPage
   , method POST >> guardCommand "cancel" >> showPage
   , method POST >> guardCommand "update" >>
       authenticate ForModify (unlessNoEdit updatePage showPage)
diff --git src/Network/Gitit/Cache.hs src/Network/Gitit/Cache.hs
index 3334d07..91b6c0a 100644
--- src/Network/Gitit/Cache.hs
+++ src/Network/Gitit/Cache.hs
@@ -41,13 +41,23 @@ import Control.Monad.Trans (liftIO)
 import Text.Pandoc.UTF8 (encodePath)
 
 -- | Expire a cached file, identified by its filename in the filestore.
+-- If there is an associated exported PDF, expire it too.
 -- Returns () after deleting a file from the cache, fails if no cached file.
 expireCachedFile :: String -> GititServerPart ()
 expireCachedFile file = do
   cfg <- getConfig
   let target = encodePath $ cacheDir cfg </> file
   exists <- liftIO $ doesFileExist target
-  when exists $ liftIO $ liftIO $ removeFile target
+  when exists $ liftIO $ do
+    liftIO $ removeFile target
+    expireCachedPDF target (defaultExtension cfg)
+
+expireCachedPDF :: String -> String -> IO ()
+expireCachedPDF file ext = 
+  when (takeExtension file == "." ++ ext) $ do
+    let pdfname = file ++ ".export.pdf"
+    exists <- doesFileExist pdfname
+    when exists $ removeFile pdfname
 
 lookupCache :: String -> GititServerPart (Maybe (UTCTime, B.ByteString))
 lookupCache file = do
@@ -74,3 +84,4 @@ cacheContents file contents = do
   liftIO $ do
     createDirectoryIfMissing True targetDir
     B.writeFile target contents
+    expireCachedPDF target (defaultExtension cfg)
diff --git src/Network/Gitit/Config.hs src/Network/Gitit/Config.hs
index d39d8cf..1bfbc47 100644
--- src/Network/Gitit/Config.hs.orig	2001-09-09 01:46:40 UTC
+++ src/Network/Gitit/Config.hs
@@ -176,6 +176,7 @@ extractConfig cfgmap = do
   cfWikiTitle <- get "DEFAULT" "wiki-title"
   cfFeedDays <- get "DEFAULT" "feed-days" >>= readNumber
   cfFeedRefreshTime <- get "DEFAULT" "feed-refresh-time" >>= readNumber
+  cfPDFExport <- get "DEFAULT" "pdf-export" >>= readBool
   cfPandocUserData <- get "DEFAULT" "pandoc-user-data"
   cfXssSanitize <- get "DEFAULT" "xss-sanitize" >>= readBool
   cfRecentActivityDays <- get "DEFAULT" "recent-activity-days" >>= readNumber
@@ -279,6 +280,7 @@ extractConfig cfgmap = do
     , wikiTitle            = cfWikiTitle
     , feedDays             = cfFeedDays
     , feedRefreshTime      = cfFeedRefreshTime
+    , pdfExport            = cfPDFExport
     , pandocUserData       = if null cfPandocUserData
                                 then Nothing
                                 else Just cfPandocUserData
diff --git src/Network/Gitit/ContentTransformer.hs src/Network/Gitit/ContentTransformer.hs
index 12e450a..fa82604 100644
--- src/Network/Gitit/ContentTransformer.hs
+++ src/Network/Gitit/ContentTransformer.hs
@@ -31,6 +31,7 @@ module Network.Gitit.ContentTransformer
   , showRawPage
   , showFileAsText
   , showPage
+  , exportPage
   , showHighlightedSource
   , showFile
   , preview
@@ -44,6 +45,7 @@ module Network.Gitit.ContentTransformer
   , textResponse
   , mimeFileResponse
   , mimeResponse
+  , exportPandoc
   , applyWikiTemplate
   -- * Content-type transformation combinators
   , pageToWikiPandoc
@@ -77,6 +79,7 @@ import Data.List (stripPrefix)
 import Data.Maybe (isNothing, mapMaybe)
 import Data.Semigroup ((<>))
 import Network.Gitit.Cache (lookupCache, cacheContents)
+import Network.Gitit.Export (exportFormats)
 import Network.Gitit.Framework hiding (uriPath)
 import Network.Gitit.Layout
 import Network.Gitit.Page (stringToPage)
@@ -183,6 +186,10 @@ showFileAsText = runFileTransformer rawTextResponse
 showPage :: Handler
 showPage = runPageTransformer htmlViaPandoc
 
+-- | Responds with page exported into selected format.
+exportPage :: Handler
+exportPage = runPageTransformer exportViaPandoc
+
 -- | Responds with highlighted source code.
 showHighlightedSource :: Handler
 showHighlightedSource = runFileTransformer highlightRawSource
@@ -213,6 +220,15 @@ applyPreCommitPlugins = runPageTransformer . applyPreCommitTransforms
 rawTextResponse :: ContentTransformer Response
 rawTextResponse = rawContents >>= textResponse
 
+-- | Responds with a wiki page in the format specified
+-- by the @format@ parameter.
+exportViaPandoc :: ContentTransformer Response
+exportViaPandoc = rawContents >>=
+                  maybe mzero return >>=
+                  contentsToPage >>=
+                  pageToWikiPandoc >>=
+                  exportPandoc
+
 -- | Responds with a wiki page. Uses the cache when
 -- possible and caches the rendered page when appropriate.
 htmlViaPandoc :: ContentTransformer Response
@@ -306,6 +322,17 @@ mimeResponse :: Monad m
 mimeResponse c mimeType =
   return . setContentType mimeType . toResponse $ c
 
+-- | Converts Pandoc to response using format specified in parameters.
+exportPandoc :: Pandoc -> ContentTransformer Response
+exportPandoc doc = do
+  params <- getParams
+  page <- getPageName
+  cfg <- lift getConfig
+  let format = pFormat params
+  case lookup format (exportFormats cfg) of
+       Nothing     -> error $ "Unknown export format: " ++ format
+       Just writer -> lift (writer page doc)
+
 -- | Adds the sidebar, page tabs, and other elements of the wiki page
 -- layout to the raw content.
 applyWikiTemplate :: Html -> ContentTransformer Response
diff --git src/Network/Gitit/Export.hs src/Network/Gitit/Export.hs
new file mode 100644
index 0000000..0842a8c
--- /dev/null
+++ src/Network/Gitit/Export.hs
@@ -0,0 +1,307 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE FlexibleContexts #-}
+{-
+Copyright (C) 2009 John MacFarlane <jgm@berkeley.edu>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+-}
+
+{- Functions for exporting wiki pages in various formats.
+-}
+
+module Network.Gitit.Export ( exportFormats ) where
+import Control.Exception (throwIO)
+import Text.Pandoc hiding (HTMLMathMethod(..), getDataFileName)
+import qualified Text.Pandoc as Pandoc
+import Text.Pandoc.PDF (makePDF)
+import Text.Pandoc.SelfContained as SelfContained
+import qualified Text.Pandoc.UTF8 as UTF8
+import qualified Data.Map as M
+import Network.Gitit.Server
+import Network.Gitit.Framework (pathForPage)
+import Network.Gitit.State (getConfig)
+import Network.Gitit.Types
+import Network.Gitit.Cache (cacheContents, lookupCache)
+import Text.DocTemplates as DT
+import Control.Monad.Trans (liftIO)
+import Control.Monad (unless)
+import Text.XHtml (noHtml)
+import qualified Data.ByteString as B
+import qualified Data.ByteString.Lazy as L
+import System.FilePath ((</>), takeDirectory)
+import System.Environment (setEnv)
+import System.Directory (doesFileExist)
+import Text.HTML.SanitizeXSS
+import Data.ByteString.Lazy (fromStrict)
+import Data.Text (Text)
+import qualified Data.Text as T
+import Data.Text.Encoding (encodeUtf8)
+import Data.List (isPrefixOf)
+import Skylighting (styleToCss, pygments)
+import System.IO.Temp (withSystemTempDirectory)
+import Paths_gitit (getDataFileName)
+
+defaultRespOptions :: WriterOptions
+defaultRespOptions = def { writerHighlightStyle = Just pygments }
+
+respondX :: String -> String -> String
+          -> (WriterOptions -> Pandoc -> PandocIO L.ByteString)
+          -> WriterOptions -> String -> Pandoc -> Handler
+respondX templ mimetype ext fn opts page doc = do
+  cfg <- getConfig
+  doc' <- if ext `elem` ["odt","pdf","beamer","epub","docx","rtf"]
+             then fixURLs page doc
+             else return doc
+  doc'' <- liftIO $ runIO $ do
+        setUserDataDir $ pandocUserData cfg
+        compiledTemplate <- compileDefaultTemplate (T.pack templ)
+        fn opts{ writerTemplate = Just compiledTemplate } doc'
+  either (liftIO . throwIO)
+         (ok . setContentType mimetype .
+           (if null ext then id else setFilename (page ++ "." ++ ext)) .
+            toResponseBS B.empty)
+         doc''
+
+respondS :: String -> String -> String -> (WriterOptions -> Pandoc -> PandocIO Text)
+          -> WriterOptions -> String -> Pandoc -> Handler
+respondS templ mimetype ext fn =
+  respondX templ mimetype ext (\o d -> fromStrict . encodeUtf8 <$> fn o d)
+
+respondSlides :: String -> (WriterOptions -> Pandoc -> PandocIO Text) -> String -> Pandoc -> Handler
+respondSlides templ fn page doc = do
+    cfg <- getConfig
+    let math = case mathMethod cfg of
+                   MathML       -> Pandoc.MathML
+                   WebTeX u     -> Pandoc.WebTeX $ T.pack u
+                   _            -> Pandoc.PlainMath
+    let opts' = defaultRespOptions { writerIncremental = True
+                                   , writerHTMLMathMethod = math}
+    -- We sanitize the body only, to protect against XSS attacks.
+    -- (Sanitizing the whole HTML page would strip out javascript
+    -- needed for the slides.)  We then pass the body into the
+    -- slide template using the 'body' variable.
+    Pandoc meta blocks <- fixURLs page doc
+    docOrError <- liftIO $ runIO $ do
+          setUserDataDir $ pandocUserData cfg
+          body' <- writeHtml5String opts' (Pandoc meta blocks) -- just body
+          let body'' = T.unpack
+                       $ (if xssSanitize cfg then sanitizeBalance else id)
+                       $ body'
+          let setVariable key val (DT.Context ctx) =
+                DT.Context $ M.insert (T.pack key) (toVal (T.pack val)) ctx
+          variables' <- if mathMethod cfg == MathML
+                          then do
+                              s <- readDataFile "MathMLinHTML.js"
+                              return $ setVariable "mathml-script"
+                                         (UTF8.toString s) mempty
+                          else return mempty
+          compiledTemplate <- compileDefaultTemplate (T.pack templ)
+          dzcore <- if templ == "dzslides"
+                      then do
+                        dztempl <- readDataFile $ "dzslides" </> "template.html"
+                        return $ unlines
+                            $ dropWhile (not . isPrefixOf "<!-- {{{{ dzslides core")
+                            $ lines $ UTF8.toString dztempl
+                      else return ""
+          let opts'' = opts'{
+                             writerVariables =
+                               setVariable "body" body'' $
+                               setVariable "dzslides-core" dzcore $
+                               setVariable "highlighting-css" pygmentsCss
+                               $ variables'
+                            ,writerTemplate = Just compiledTemplate }
+          h <- fn opts'' (Pandoc meta [])
+          makeSelfContained h
+    either (liftIO . throwIO)
+           (ok . setContentType "text/html;charset=UTF-8" .
+             (setFilename (page ++ ".html")) .
+             toResponseBS B.empty . L.fromStrict . UTF8.fromText)
+           docOrError
+
+respondLaTeX :: String -> Pandoc -> Handler
+respondLaTeX = respondS "latex" "application/x-latex" "tex"
+  writeLaTeX defaultRespOptions
+
+respondConTeXt :: String -> Pandoc -> Handler
+respondConTeXt = respondS "context" "application/x-context" "tex"
+  writeConTeXt defaultRespOptions
+
+
+respondRTF :: String -> Pandoc -> Handler
+respondRTF = respondX "rtf" "application/rtf" "rtf"
+  (\o d -> L.fromStrict . UTF8.fromText <$> writeRTF o d) defaultRespOptions
+
+respondRST :: String -> Pandoc -> Handler
+respondRST = respondS "rst" "text/plain; charset=utf-8" ""
+  writeRST defaultRespOptions{writerReferenceLinks = True}
+
+respondMarkdown :: String -> Pandoc -> Handler
+respondMarkdown = respondS "markdown" "text/plain; charset=utf-8" ""
+  writeMarkdown defaultRespOptions{writerReferenceLinks = True}
+
+respondCommonMark :: String -> Pandoc -> Handler
+respondCommonMark = respondS "commonmark" "text/plain; charset=utf-8" ""
+  writeCommonMark defaultRespOptions{writerReferenceLinks = True}
+
+respondPlain :: String -> Pandoc -> Handler
+respondPlain = respondS "plain" "text/plain; charset=utf-8" ""
+  writePlain defaultRespOptions
+
+respondMan :: String -> Pandoc -> Handler
+respondMan = respondS "man" "text/plain; charset=utf-8" ""
+  writeMan defaultRespOptions
+
+respondTexinfo :: String -> Pandoc -> Handler
+respondTexinfo = respondS "texinfo" "application/x-texinfo" "texi"
+  writeTexinfo defaultRespOptions
+
+respondDocbook :: String -> Pandoc -> Handler
+respondDocbook = respondS "docbook" "application/docbook+xml" "xml"
+  writeDocbook5 defaultRespOptions
+
+respondOrg :: String -> Pandoc -> Handler
+respondOrg = respondS "org" "text/plain; charset=utf-8" ""
+  writeOrg defaultRespOptions
+
+respondICML :: String -> Pandoc -> Handler
+respondICML = respondX "icml" "application/xml; charset=utf-8" ""
+              (\o d -> L.fromStrict . UTF8.fromText <$> writeICML o d)
+                         defaultRespOptions
+
+respondTextile :: String -> Pandoc -> Handler
+respondTextile = respondS "textile" "text/plain; charset=utf-8" ""
+  writeTextile defaultRespOptions
+
+respondAsciiDoc :: String -> Pandoc -> Handler
+respondAsciiDoc = respondS "asciidoc" "text/plain; charset=utf-8" ""
+  writeAsciiDoc defaultRespOptions
+
+respondMediaWiki :: String -> Pandoc -> Handler
+respondMediaWiki = respondS "mediawiki" "text/plain; charset=utf-8" ""
+  writeMediaWiki defaultRespOptions
+
+respondODT :: String -> Pandoc -> Handler
+respondODT = respondX "opendocument" "application/vnd.oasis.opendocument.text"
+              "odt" writeODT defaultRespOptions
+
+respondEPUB :: String -> Pandoc -> Handler
+respondEPUB = respondX "html" "application/epub+zip" "epub" writeEPUB3
+               defaultRespOptions
+
+respondDocx :: String -> Pandoc -> Handler
+respondDocx = respondX "native"
+  "application/vnd.openxmlformats-officedocument.wordprocessingml.document"
+  "docx" writeDocx defaultRespOptions
+
+respondPDF :: Bool -> String -> Pandoc -> Handler
+respondPDF useBeamer page old_pndc = fixURLs page old_pndc >>= \pndc -> do
+  cfg <- getConfig
+  unless (pdfExport cfg) $ error "PDF export disabled"
+  let cacheName = pathForPage page (defaultExtension cfg) ++ ".export.pdf"
+  cached <- if useCache cfg
+               then lookupCache cacheName
+               else return Nothing
+  pdf' <- case cached of
+            Just (_modtime, bs) -> return $ Right $ L.fromChunks [bs]
+            Nothing -> liftIO $
+                withSystemTempDirectory "gitit" $ \tmpdir -> do
+              let toc = tableOfContents cfg
+              -- ensure that LaTeX \include commands can't include
+              -- files outside the working directory, e.g. /etc/passwd:
+              writeFile (tmpdir </> "texmf.cnf")
+                "openout_any = p\nopenin_any = p\n"
+              setEnv "TEXMFCNF" (tmpdir ++ ":")
+              res <- runIO $ do
+                setUserDataDir $ pandocUserData cfg
+                setInputFiles [baseUrl cfg]
+                let templ = if useBeamer then "beamer" else "latex"
+                compiledTemplate <- compileDefaultTemplate templ
+                makePDF "pdflatex" [] (if useBeamer then writeBeamer else writeLaTeX)
+                  defaultRespOptions{ writerTemplate = Just compiledTemplate
+                                    , writerTableOfContents = toc } pndc
+              either (liftIO . throwIO) return res
+
+  case pdf' of
+       Left logOutput' -> simpleErrorHandler ("PDF creation failed:\n"
+                           ++ UTF8.toStringLazy logOutput')
+       Right pdfBS -> do
+              case cached of
+                Nothing ->
+                     cacheContents cacheName $ B.concat . L.toChunks $ pdfBS
+                _ -> return ()
+              ok $ setContentType "application/pdf" $ setFilename (page ++ ".pdf") $
+                        (toResponse noHtml) {rsBody = pdfBS}
+
+-- | When we create a PDF or ODT from a Gitit page, we need to fix the URLs of any
+-- images on the page. Those URLs will often be relative to the staticDir, but the
+-- PDF or ODT processor only understands paths relative to the working directory.
+--
+-- Because the working directory will not in general be the root of the gitit instance
+-- at the time the Pandoc is fed to e.g. pdflatex, this function replaces the URLs of
+-- images in the staticDir with their correct absolute file path.
+fixURLs :: String -> Pandoc -> GititServerPart Pandoc
+fixURLs page pndc = do
+    cfg <- getConfig
+    defaultStatic <- liftIO $ getDataFileName $ "data" </> "static"
+
+    let static = staticDir cfg
+    let repoPath = repositoryPath cfg
+
+    let go (Image attr ils (url, title)) = do
+           fixedURL <- fixURL $ T.unpack url
+           return $ Image attr ils (T.pack fixedURL, title)
+        go x                        = return x
+
+        fixURL ('/':url) = resolve url
+        fixURL url       = resolve $ takeDirectory page </> url
+
+        resolve p = do
+           sp <- doesFileExist $ static </> p
+           dsp <- doesFileExist $ defaultStatic </> p
+           return (if sp then static </> p
+                   else (if dsp then defaultStatic </> p
+                         else repoPath </> p))
+    liftIO $ bottomUpM go pndc
+
+exportFormats :: Config -> [(String, String -> Pandoc -> Handler)]
+exportFormats cfg = if pdfExport cfg
+                       then ("PDF", respondPDF False) :
+                            ("Beamer", respondPDF True) :
+                            rest
+                       else rest
+   where rest = [ ("LaTeX",     respondLaTeX)     -- (description, writer)
+                , ("ConTeXt",   respondConTeXt)
+                , ("Texinfo",   respondTexinfo)
+                , ("reST",      respondRST)
+                , ("Markdown",  respondMarkdown)
+                , ("CommonMark",respondCommonMark)
+                , ("Plain text",respondPlain)
+                , ("MediaWiki", respondMediaWiki)
+                , ("Org-mode",  respondOrg)
+                , ("ICML",      respondICML)
+                , ("Textile",   respondTextile)
+                , ("AsciiDoc",  respondAsciiDoc)
+                , ("Man page",  respondMan)
+                , ("DocBook",   respondDocbook)
+                , ("DZSlides",  respondSlides "dzslides" writeDZSlides)
+                , ("Slidy",     respondSlides "slidy" writeSlidy)
+                , ("S5",        respondSlides "s5" writeS5)
+                , ("EPUB",      respondEPUB)
+                , ("ODT",       respondODT)
+                , ("DOCX",      respondDocx)
+                , ("RTF",       respondRTF) ]
+
+pygmentsCss :: String
+pygmentsCss = styleToCss pygments
diff --git src/Network/Gitit/Handlers.hs src/Network/Gitit/Handlers.hs
index 44b19fe..d9f894f 100644
--- src/Network/Gitit/Handlers.hs
+++ src/Network/Gitit/Handlers.hs
@@ -42,6 +42,7 @@ module Network.Gitit.Handlers (
                       , showPage
                       , showPageDiff
                       , showFileDiff
+                      , exportPage
                       , updatePage
                       , editPage
                       , deletePage
@@ -60,7 +61,7 @@ import Network.Gitit.Feed (filestoreToXmlFeed, FeedConfig(..))
 import Network.Gitit.Util (orIfNull)
 import Network.Gitit.Cache (expireCachedFile, lookupCache, cacheContents)
 import Network.Gitit.ContentTransformer (showRawPage, showFileAsText, showPage,
-        showHighlightedSource, preview, applyPreCommitPlugins)
+        exportPage, showHighlightedSource, preview, applyPreCommitPlugins)
 import Network.Gitit.Page (readCategories)
 import qualified Control.Exception as E
 import System.FilePath
diff --git src/Network/Gitit/Layout.hs src/Network/Gitit/Layout.hs
index f835d42..fd307c7 100644
--- src/Network/Gitit/Layout.hs
+++ src/Network/Gitit/Layout.hs
@@ -31,11 +31,12 @@ import Network.Gitit.Server
 import Network.Gitit.Framework
 import Network.Gitit.State
 import Network.Gitit.Types
+import Network.Gitit.Export (exportFormats)
 import Network.HTTP (urlEncodeVars)
 import qualified Text.StringTemplate as T
 import Text.XHtml hiding ( (</>), dir, method, password, rev )
 import Text.XHtml.Strict ( stringToHtmlString )
-import Data.Maybe (isNothing)
+import Data.Maybe (isNothing, isJust, fromJust)
 
 defaultPageLayout :: PageLayout
 defaultPageLayout = PageLayout
@@ -110,6 +111,8 @@ filledPageTemplate base' cfg layout htmlContents templ =
                    maybe id (T.setAttribute "markuphelp") (pgMarkupHelp layout) .
                    setBoolAttr "printable" (pgPrintable layout) .
                    maybe id (T.setAttribute "revision") rev .
+                   T.setAttribute "exportbox"
+                       (renderHtmlFragment $  exportBox base' cfg page rev) .
                    (if null (pgTabs layout) then id else T.setAttribute "tabs"
                        (renderHtmlFragment tabs)) .
                    (\f x xs -> if null xs then x else f xs) (T.setAttribute "messages") id (pgMessages layout) .
@@ -119,6 +122,17 @@ filledPageTemplate base' cfg layout htmlContents templ =
                    templ
 
 
+exportBox :: String -> Config -> String -> Maybe String -> Html
+exportBox base' cfg page rev | not (isSourceCode page) =
+  gui (base' ++ urlForPage page) ! [identifier "exportbox"] <<
+    ([ textfield "revision" ! [thestyle "display: none;",
+         value (fromJust rev)] | isJust rev ] ++
+     [ select ! [name "format"] <<
+         map ((\f -> option ! [value f] << f) . fst) (exportFormats cfg)
+     , primHtmlChar "nbsp"
+     , submit "export" "Export" ])
+exportBox _ _ _ _ = noHtml
+
 -- auxiliary functions:
 
 linkForTab :: (Tab -> Html -> Html) -> String -> String -> Maybe String -> Tab -> Html
diff --git src/Network/Gitit/Types.hs src/Network/Gitit/Types.hs
index aa23ec1..8f037b9 100644
--- src/Network/Gitit/Types.hs
+++ src/Network/Gitit/Types.hs
@@ -204,6 +204,8 @@ data Config = Config {
   feedDays             :: Integer,
   -- | Number of minutes to cache feeds before refreshing
   feedRefreshTime      :: Integer,
+  -- | Allow PDF export?
+  pdfExport            :: Bool,
   -- | Directory to search for pandoc customizations
   pandocUserData       :: Maybe FilePath,
   -- | Filter HTML through xss-sanitize
@@ -465,7 +467,7 @@ instance FromData Command where
        return $ case map fst pairs `intersect` commandList of
                  []          -> Command Nothing
                  (c:_)       -> Command $ Just c
-               where commandList = ["update", "cancel"]
+               where commandList = ["update", "cancel", "export"]
 
 -- | State for a single wiki.
 data WikiState = WikiState {