X-Git-Url: http://gitweb.michael.orlitzky.com/?p=dead%2Flwn-epub.git;a=blobdiff_plain;f=src%2FLWN%2FHTTP.hs;h=6216a0f1282e7a7fb1cb674ee557062254328438;hp=8b4c14d0cc04a09badc271f15bd0ea628ca24390;hb=cf0659082f2d0e6afa6b43a6ad55432a00b155e9;hpb=241e9b547e48d4af7eb37ca6989775c0d09152bc

diff --git a/src/LWN/HTTP.hs b/src/LWN/HTTP.hs
index 8b4c14d..6216a0f 100644
--- a/src/LWN/HTTP.hs
+++ b/src/LWN/HTTP.hs
@@ -1,120 +1,198 @@
+{-# LANGUAGE DoAndIfThenElse #-}
+
 module LWN.HTTP
 where
 
-import Network.Curl (
-  CurlCode(..),
-  CurlOption(..),
-  CurlResponse,
-  URLString,
-  do_curl_,
-  initialize,
-  respBody,
-  respCurlCode,
-  withCurlDo               
+import Control.Concurrent.ParallelIO (parallel)
+import qualified Data.ByteString.Char8 as C (ByteString, pack)
+import qualified Data.ByteString.Lazy as L (ByteString, hPut)
+import Data.ByteString.Lazy.UTF8 (toString)
+import qualified Data.Map as Map (Map, empty, insert)
+import Data.Maybe (fromJust, isNothing)
+import Data.Time (getCurrentTime)
+import Network.HTTP.Conduit (
+  CookieJar,
+  Response(..),
+  Request(..),
+  httpLbs,
+  insertCookiesIntoRequest,
+  parseUrl,
+  updateCookieJar,
+  urlEncodedBody,
+  withManager
   )
+import Network.HTTP.Types (status200, status302)
+import Network.HTTP.Types.Method (methodPost)
+import System.Directory (doesFileExist, getTemporaryDirectory)
 import System.IO (hPutStrLn, stderr)
+import qualified System.IO.UTF8 as Utf8 (readFile)
+import System.IO.Temp (openBinaryTempFile)
 
-login_url :: URLString
-login_url = "https://lwn.net/login"
+-- Also grab the empty cookie jar from Configuration since we'll
+-- use it in a few places.
+import qualified Configuration as C (Cfg(..), cj_empty)
+import LWN.Article (real_article_path)
+import LWN.URI (URL, filename)
 
-username_field :: String
-username_field = "Username"
+-- | The type of response we get back from http-conduit's httpLbs.
+type LBSResponse = Response L.ByteString
 
-password_field :: String
-password_field = "Password"
 
-submit_field :: String
-submit_field = "submit"
+login_url :: URL
+login_url = "https://lwn.net/login"
+
+username_field :: C.ByteString
+username_field = C.pack "Username"
 
+password_field :: C.ByteString
+password_field = C.pack "Password"
 
-default_curl_opts :: [CurlOption]
-default_curl_opts =
-  [ -- The Global cache is not thread-friendly.
-    CurlDNSUseGlobalCache False,
-    
-    -- And we don't want to use a DNS cache anyway.
-    CurlDNSCacheTimeout 0,
+submit_field :: C.ByteString
+submit_field = C.pack "submit"
 
-    -- Give it a little time...
-    CurlTimeout 45,
 
-    -- And let us know when things go wrong.
-    CurlVerbose True ]
+-- | Get the requested URL as a L.ByteString, or return the response
+--   as an error. Use the given cookie jar for the request.
+get_page :: CookieJar -> URL -> IO (Either LBSResponse L.ByteString)
+get_page cj url = do
+  init_req <- parseUrl url
+  let req' = init_req { checkStatus = \_ _ -> Nothing }
+  now <- getCurrentTime
+  let (req, _) = insertCookiesIntoRequest req' cj now
+  resp <- withManager $ httpLbs req
 
+  return $ if (responseStatus resp) == status200 then
+             Right (responseBody resp)
+           else
+             Left resp
 
 
-get_page :: Maybe FilePath -> URLString -> IO (Maybe String)
-get_page cookie_jar url =
-  withCurlDo $ do
-    -- Create a curl instance.
-    curl <- initialize
+-- | Log in using curl. Store the resulting session cookies in the
+--   supplied file.
+log_in :: String -> String -> IO (Either LBSResponse CookieJar)
+log_in username password = do
+  init_req <- parseUrl login_url
+  let req' = init_req { method = methodPost,
+                        checkStatus = \_ _ -> Nothing,
+                        redirectCount = 0 }
+  let req = urlEncodedBody post_data req'
 
-    -- Perform the request, and get back a CurlResponse object.
-    -- The cast is needed to specify how we would like our headers
-    -- and body returned (Strings).
-    resp <- do_curl_ curl login_url curl_opts :: IO CurlResponse
+  resp <- withManager $ httpLbs req
 
-    -- Pull out the response code as a CurlCode.
-    let code = respCurlCode resp
+  -- The login page redirects. If we follow it, we lose our cookies.
+  if (responseStatus resp) == status302 then do
+    now <- getCurrentTime
+    let (cj,_) = updateCookieJar resp req now C.cj_empty
+    return $ Right cj
+  else do
+    return $ Left resp
 
-    case code of
-      CurlOK -> return $ Just (respBody resp)
-      error_code -> do
-        hPutStrLn stderr ("HTTP Error: " ++ (show error_code))
-        -- If an error occurred, we want to dump as much information as
-        -- possible. If this becomes a problem, we can use respGetInfo to
-        -- query the response object for more information
-        return Nothing
   where
-    get_opts =
-      case cookie_jar of
-        Nothing -> []
-        Just cookies -> [ CurlCookieJar cookies ]
-
-    curl_opts = default_curl_opts ++ get_opts
-
-
-log_in :: FilePath -> String -> String -> IO Bool
-log_in cookie_jar username password =
-  withCurlDo $ do
-    -- Create a curl instance.
-    curl <- initialize
-
-    -- Perform the request, and get back a CurlResponse object.
-    -- The cast is needed to specify how we would like our headers
-    -- and body returned (Strings).
-    resp <- do_curl_ curl login_url curl_opts :: IO CurlResponse
-
-    -- Pull out the response code as a CurlCode.
-    let code = respCurlCode resp
-
-    case code of
-      CurlOK -> return True
-      error_code -> do
-        hPutStrLn stderr ("HTTP Error: " ++ (show error_code))
-        -- If an error occurred, we want to dump as much information as
-        -- possible. If this becomes a problem, we can use respGetInfo to
-        -- query the response object for more information
-        return False
+    post_submit :: (C.ByteString, C.ByteString)
+    post_submit = (submit_field, C.pack "Log+In")
+
+    post_username :: (C.ByteString, C.ByteString)
+    post_username = (username_field, C.pack username)
+
+    post_password :: (C.ByteString, C.ByteString)
+    post_password = (password_field, C.pack password)
+
+    post_data :: [(C.ByteString, C.ByteString)]
+    post_data = [post_username, post_password, post_submit]
+
+
+
+-- | Save the image at 'url'. Saves to a temporary file, and
+--   returns the path to that file if successful. Otherwise,
+--   returns 'Nothing'.
+--
+--   We need to be able to parse the filename out of the URL
+--   so that when we stick our image in the document, the reader
+--   knows that type (jpg, png, etc.) it is.
+save_image :: URL -> IO (Maybe FilePath)
+save_image url = do
+  it_exists <- doesFileExist url
+  if it_exists then do
+    -- It's local, just use it.
+    return $ Just url
+  else do
+    let fn = filename url
+    case fn of
+      Nothing -> return Nothing
+      Just file -> do
+        temp_dir <- getTemporaryDirectory
+        (out_path, out_handle) <- openBinaryTempFile temp_dir file
+        -- We don't need to be logged in to get the images, so use an
+        -- empty cookie jar.
+        result <- get_page C.cj_empty url
+        case result of
+          Left err -> do
+            hPutStrLn stderr $ "Failed to retrieve image. " ++
+                               "Server response:\n" ++ (show err)
+            return Nothing
+          Right bs -> do
+            L.hPut out_handle bs
+            return $ Just out_path
+
+
+
+
+-- | Map absolute image URLs to local system file paths where the
+--   image referenced by the URL is stored.
+type ImageMap = Map.Map URL FilePath
+
+download_image_urls :: [URL] -> IO ImageMap
+download_image_urls image_urls = do
+  files <- parallel $ map save_image image_urls
+  let pairs = zip image_urls files
+  return $ foldl my_insert empty_map pairs
   where
-    post_submit :: String
-    post_submit = submit_field ++ "=Log+In"
-
-    post_username :: String
-    post_username = username_field ++ "=" ++ username
-
-    post_password :: String
-    post_password = password_field ++ "=" ++ password
-
-    post_data :: [String]
-    post_data = [post_username, post_password]
-
-    post_opts :: [CurlOption]
-    post_opts =
-      [ CurlCookieSession True,
-        CurlCookieJar cookie_jar,
-        CurlPost True,
-        CurlPostFields post_data ]
-        
-    curl_opts :: [CurlOption]
-    curl_opts = default_curl_opts ++ post_opts
+    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
+
+
+
+
+
+get_login_cookie :: C.Cfg -> IO C.Cfg
+get_login_cookie cfg
+  | isNothing (C.username cfg) = return cfg
+  | isNothing (C.password cfg) = return cfg
+  | otherwise = do
+      let uname = fromJust $ C.username cfg
+      let pword = fromJust $ C.password cfg
+      li_result <- log_in uname pword
+
+      case li_result of
+        Left err -> do
+          let msg = "Failed to log in. Server response:\n" ++ (show err)
+          hPutStrLn stderr msg
+          return cfg
+        Right cj -> return $ cfg { C.cookie_jar = cj }
+
+
+-- | Try to parse the given article using HXT. We try a few different
+--   methods; if none of them work, we return 'Nothing'.
+get_article_contents :: C.Cfg -> URL -> IO (Maybe String)
+get_article_contents cfg article_name = do
+  my_article <- real_article_path article_name
+  is_file <- doesFileExist my_article
+  case is_file of
+    True -> do
+      contents <- Utf8.readFile my_article
+      return $ Just $ contents
+    False -> do
+      -- Download the URL.
+      html <- get_page (C.cookie_jar cfg) my_article
+
+      case html of
+        Left err -> do
+          let msg = "Failed to retrieve article. " ++
+                    "Server response:\n" ++ (show err)
+          hPutStrLn stderr msg
+          return Nothing
+        Right lbs_article ->
+          return $ Just (toString lbs_article)