module LWN.Page
where
-import qualified Data.Map as Map
+import Control.Concurrent.ParallelIO (parallel)
+import qualified Data.Map as Map (lookup)
import Data.Time (getCurrentTime)
-import System.IO (Handle)
import qualified Data.ByteString.Lazy as B (ByteString, hPut)
import Data.String.Utils (split, strip)
+import qualified Data.Map as Map (Map, empty, insert)
import Data.Maybe (catMaybes, fromJust, isNothing)
-import Data.Tree.NTree.TypeDefs (NTree)
+import Prelude hiding (readFile)
+import System.IO (Handle, hClose, hFlush)
import Test.HUnit (Assertion, assertEqual)
import Test.Framework (Test, testGroup)
import Test.Framework.Providers.HUnit (testCase)
-import Text.Pandoc
+import Text.Pandoc (
+ defaultParserState,
+ defaultWriterOptions,
+ readHtml,
+ writeEPUB,
+ writerEPUBMetadata)
import Text.XML.HXT.Core (
ArrowXml,
IOSArrow,
XmlTree,
- XNode,
+ ($<),
(>>>),
(/>),
(//>),
getAttrValue,
getChildren,
getText,
- hasAttrValue,
hasName,
- isElem,
- mkName,
- none,
processAttrl,
processTopDown,
+ this,
runX,
- setElemName,
xshow,
- when
- )
+ when)
import Text.HandsomeSoup (css, parseHtml)
+import Configuration (Cfg, full_stories)
import LWN.Article
-import LWN.HTTP (save_image)
-import LWN.URI (URL, try_make_absolute_url)
-import Misc (contains)
-import XHTML
+import LWN.HTTP (
+ ImageMap,
+ download_image_urls,
+ get_article_contents)
+import LWN.URI (URL)
+import LWN.XHTML (
+ XHTML,
+ full_story_urls,
+ image_srcs,
+ full_story_link,
+ full_story_paragraph,
+ is_image,
+ preprocess,
+ remove_byline,
+ remove_full_story_paragraphs,
+ remove_title,
+ to_xhtml,
+ to_xml,
+ xml_from_contents)
--- Map absolute image URLs to local system file paths where the image
--- referenced by the URL is stored.
-type ImageMap = Map.Map URL FilePath
--- Should be called *after* preprocessing.
-download_images :: IOSArrow XmlTree (NTree XNode) -> IO ImageMap
-download_images xml = do
- image_urls <- runX $ xml >>> image_srcs
- files <- mapM save_image image_urls
- let pairs = zip image_urls files
- return $ foldl my_insert empty_map pairs
- where
- empty_map = Map.empty :: ImageMap
-
- my_insert :: ImageMap -> (URL, Maybe FilePath) -> ImageMap
- my_insert dict (_, Nothing) = dict
- my_insert dict (k, Just v) = Map.insert k v dict
data Page =
" <title>" ++ (show $ LWN.Article.title a) ++ "</title>" ++
"</head>" ++
"<body>" ++
- "<div>" ++
(to_xhtml a) ++
- "</div>" ++
"</body>" ++
"</html>"
-is_link :: (ArrowXml a) => a XmlTree XmlTree
-is_link =
- isElem >>> hasName "a"
+page_from_url :: Cfg -> URL -> IO (Maybe Page)
+page_from_url cfg url = do
+ contents <- get_article_contents cfg url
+ case (xml_from_contents contents) of
+ Just html -> parse cfg html
+ Nothing -> return Nothing
-remove_comment_links :: (ArrowXml a) => a XmlTree XmlTree
-remove_comment_links =
- processTopDown $ kill_comments `when` is_link
- where
- is_comment_link =
- hasAttrValue "href" (contains "#Comments")
- kill_comments =
- none `when` is_comment_link
-
-replace_links_with_spans :: (ArrowXml a) => a XmlTree XmlTree
-replace_links_with_spans =
- processTopDown $ (make_span >>> remove_attrs) `when` is_link
+insert_full_stories :: (ArrowXml a) => StoryMap -> a XmlTree XmlTree
+insert_full_stories story_map =
+ processTopDown (article_xml `when` full_story_paragraph)
where
- make_span = setElemName $ mkName "span"
- remove_attrs = processAttrl none
-
-
--- | Preprocessing common to both page types.
-preprocess :: (ArrowXml a) => a XmlTree XmlTree
-preprocess =
- make_image_srcs_absolute
- >>>
- remove_comment_links
- >>>
- replace_links_with_spans
-
-
+ lookup_func :: (ArrowXml a) => URL -> a XmlTree XmlTree
+ lookup_func href =
+ case Map.lookup href story_map of
+ -- Leave it alone if we don't have the full story.
+ Nothing -> this
+ Just v -> to_xml v
+
+ article_xml :: (ArrowXml a) => a XmlTree XmlTree
+ article_xml =
+ lookup_func
+ $< -- From HXT's Control.Arrow.ArrowList
+ (this /> full_story_link >>> getAttrValue "href")
+
replace_remote_img_srcs :: (ArrowXml a) => ImageMap -> a XmlTree XmlTree
replace_remote_img_srcs image_map =
processTopDown (make_srcs_local `when` is_image)
processAttrl $ (change_src `when` (hasName "src"))
-parse :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe Page)
-parse xml = do
- let clean_xml = xml >>> preprocess
+
+
+-- Should be called *after* preprocessing.
+download_images :: IOSArrow XmlTree XmlTree -> IO ImageMap
+download_images xml = do
+ image_urls <- runX $ xml >>> image_srcs
+ download_image_urls image_urls
+
+
+
+type StoryMap = Map.Map URL Article
+
+-- These come *before* preprocessing.
+download_full_story_urls :: Cfg -> [URL] -> IO StoryMap
+download_full_story_urls cfg story_urls = do
+ pages <- parallel $ map (page_from_url cfg) story_urls
+ let pairs = zip story_urls pages
+ return $ foldl my_insert empty_map pairs
+ where
+ empty_map = Map.empty :: StoryMap
+
+ my_insert :: StoryMap -> (URL, Maybe Page) -> StoryMap
+ my_insert dict (k, Just (ArticlePage v)) = Map.insert k v dict
+ my_insert dict (_, _) = dict
+
+
+download_full_stories :: Cfg -> IOSArrow XmlTree XmlTree -> IO StoryMap
+download_full_stories cfg xml = do
+ story_urls <- runX $ xml >>> full_story_urls
+ download_full_story_urls cfg story_urls
+
+
+parse :: Cfg -> IOSArrow XmlTree XmlTree -> IO (Maybe Page)
+parse cfg xml = do
+ fs_xml <- if (full_stories cfg) then do
+ story_map <- download_full_stories cfg xml
+ return $ xml >>> insert_full_stories story_map
+ else do
+ -- Get rid of them if we don't want them.
+ return $ xml >>> remove_full_story_paragraphs
+
+ let clean_xml = fs_xml >>> preprocess
image_map <- download_images clean_xml
let local_xml = clean_xml >>> replace_remote_img_srcs image_map
+
appr <- ap_parse local_xml
fppr <- fp_parse local_xml
return $
if (isNothing appr) then
fppr
- else
+ else
appr
-parse_headline :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe String)
+parse_headline :: IOSArrow XmlTree XmlTree -> IO (Maybe String)
parse_headline xml = do
let element_filter = xml >>> css "div.PageHeadline h1"
let element_text_filter = element_filter /> getText
_ -> error "Found more than one headline."
-parse_byline :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe String)
+parse_byline :: IOSArrow XmlTree XmlTree -> IO (Maybe String)
parse_byline xml = do
let element_filter = xml >>> css "div.FeatureByLine"
let element_text_filter = element_filter /> getText
--
-- ArticlePage Stuff
--
-ap_parse :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe Page)
+ap_parse :: IOSArrow XmlTree XmlTree -> IO (Maybe Page)
ap_parse xml = do
- arts <- ap_parse_articles xml
+ arts <- ap_parse_articles xml
case arts of
[x] -> return $ Just $ ArticlePage x
_ -> return Nothing
-
-ap_parse_body :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe String)
+
+ap_parse_body :: IOSArrow XmlTree XmlTree -> IO (Maybe String)
ap_parse_body xml = do
let element_filter = xml >>> css "div.ArticleText"
let element_html_filter = xshow element_filter
_ -> error "Found more than one article."
-ap_parse_articles :: IOSArrow XmlTree (NTree XNode) -> IO [Article]
+ap_parse_articles :: IOSArrow XmlTree XmlTree -> IO [Article]
ap_parse_articles xml = do
parsed_headline <- parse_headline xml
parsed_byline <- parse_byline xml
parsed_body <- ap_parse_body xml
- putStrLn $ fromJust parsed_headline
-
if (isNothing parsed_headline) || (isNothing parsed_body)
then return []
- else do
+ else do
let title' = Title $ fromJust parsed_headline
let byline' = Byline parsed_byline
let body' = BodyHtml $ fromJust parsed_body
-
+
return $ [Article title' byline' body']
-- FullPage Stuff
--
-fp_parse :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe Page)
+fp_parse :: IOSArrow XmlTree XmlTree -> IO (Maybe Page)
fp_parse xml = do
hl <- parse_headline xml
parsed_articles <- fp_parse_articles xml
-fp_parse_article_title :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe String)
+fp_parse_article_title :: IOSArrow XmlTree XmlTree -> IO (Maybe String)
fp_parse_article_title xml = do
let element_filter = xml >>> css "h2.SummaryHL"
let element_text_filter = element_filter //> getText
-is_title :: (ArrowXml a) => a XmlTree XmlTree
-is_title =
- (hasName "h2")
- >>>
- (hasAttrValue "class" (== "SummaryHL"))
-
-
-is_byline :: (ArrowXml a) => a XmlTree XmlTree
-is_byline =
- (hasName "div")
- >>>
- (hasAttrValue "class" (== "FeatureByLine"))
-
-
-is_image :: (ArrowXml a) => a XmlTree XmlTree
-is_image = isElem >>> hasName "img"
-remove_title :: (ArrowXml a) => a XmlTree XmlTree
-remove_title =
- processTopDown ((none) `when` is_title)
-
-
-remove_byline :: (ArrowXml a) => a XmlTree XmlTree
-remove_byline =
- processTopDown ((none) `when` is_byline)
-
-
-
-fp_parse_article_body :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe String)
+fp_parse_article_body :: IOSArrow XmlTree XmlTree -> IO (Maybe String)
fp_parse_article_body xml = do
-- First, delete the article title and byline.
let clean_xml' = xml >>> remove_title >>> remove_byline
[] -> Nothing
_ -> error "Found more than one article body."
-fp_parse_article :: IOSArrow XmlTree (NTree XNode) -> IO (Maybe Article)
+fp_parse_article :: IOSArrow XmlTree XmlTree -> IO (Maybe Article)
fp_parse_article xml = do
parsed_article_title <- fp_parse_article_title xml
parsed_article_byline <- parse_byline xml
let xml = parseHtml $ wrap_in_body_div html
fp_parse_article xml
-
+
-- | In the full page, all of the article titles and bodies are
-- wrapped in one big div.ArticleText.
-parse_bodies :: IOSArrow XmlTree (NTree XNode) -> IOSArrow XmlTree (NTree XNode)
+parse_bodies :: IOSArrow XmlTree XmlTree -> IOSArrow XmlTree XmlTree
parse_bodies xml =
xml >>> css "div.ArticleText"
-fp_parse_articles :: IOSArrow XmlTree (NTree XNode) -> IO [Article]
+fp_parse_articles :: IOSArrow XmlTree XmlTree -> IO [Article]
fp_parse_articles xml = do
bodies <- runX . xshow $ parse_bodies xml
let article_separator = "<h2 class=\"SummaryHL\">"
[] -> []
-- Put the separator back, it was lost during the split.
let split_articles = map (article_separator ++) split_articles'
- --_ <- mapM print_article split_articles
real_articles <- mapM parse_html_article split_articles
let just_articles = catMaybes real_articles
return just_articles
epmd <- metadata obj
epub <- xhtml_to_epub epmd xhtml
B.hPut handle epub
-
+ hFlush handle
+ hClose handle
xhtml_to_epub :: String -> String -> IO B.ByteString
xhtml_to_epub epmd =
read_html = readHtml defaultParserState
-
---
--- Misc
---
-
-image_srcs :: (ArrowXml a) => a XmlTree URL
-image_srcs =
- css "img"
- >>>
- getAttrValue "src"
-
-make_image_srcs_absolute :: (ArrowXml a) => a XmlTree XmlTree
-make_image_srcs_absolute =
- processTopDown (make_srcs_absolute `when` is_image)
- where
- change_src :: (ArrowXml a) => a XmlTree XmlTree
- change_src =
- changeAttrValue try_make_absolute_url
-
- make_srcs_absolute :: (ArrowXml a) => a XmlTree XmlTree
- make_srcs_absolute =
- processAttrl $ change_src `when` hasName "src"
-
-
--
-- Tests
--
expected_xml'' = parseHtml expected_html
+test_full_story_urls_parsed :: Assertion
+test_full_story_urls_parsed = do
+ actual <- runX $ actual'
+
+ assertEqual
+ "Full Story URLs are parsed"
+ expected
+ actual
+ where
+ expected = ["/Articles/500738/", "/Articles/501837/"]
+
+ full_story_html =
+ concat ["<p>",
+ "<a href=\"/Articles/500738/\">Full Story</a> ",
+ "(<a href=\"/Articles/500738/#Comments\">comments: 49</a>)",
+ "<p>",
+ "<a href=\"/Articles/501837/\">Full Story</a> ",
+ "(<a href=\"/Articles/501837/#Comments\">comments: none</a>)",
+ "<p>"]
+
+ xml = parseHtml full_story_html
+ actual' = xml >>> full_story_urls
page_tests :: Test
page_tests =
testGroup "Page Tests" [
testCase "Links are replaced with spans" test_preprocess_links,
testCase "Image srcs are made absolute" test_absolve_images,
- testCase "Comment links are removed" test_comments_removed ]
+ testCase "Comment links are removed" test_comments_removed,
+ testCase "Full Story URLs are parsed" test_full_story_urls_parsed ]