Source reorganization and cleanup.

[dead/lwn-epub.git] / src / LWN / HTTP.hs

diff --git a/src/LWN/HTTP.hs b/src/LWN/HTTP.hs
index 3793f10ae7470966d5b1526bcdf435af05f6fb5a..a8a1980f273cfdc352911bb7bcd3b55b58137cdf 100644 (file)
--- a/src/LWN/HTTP.hs
+++ b/src/LWN/HTTP.hs
@@ -4,26 +4,25 @@ module LWN.HTTP
 where
 
 import qualified Data.ByteString as B (hPut)
-
+import qualified Data.Map as Map (Map, empty, insert)
 import Network.Curl (
   CurlCode(..),
   CurlOption(..),
   CurlResponse,
-  URLString,
   do_curl_,
   initialize,
   respBody,
   respCurlCode,
-  withCurlDo               
+  withCurlDo
   )
 import Network.Curl.Download (openURI)
 import System.Directory (doesFileExist, getTemporaryDirectory)
 import System.IO (hClose, hPutStrLn, stderr)
 import System.IO.Temp (openBinaryTempFile, openTempFile)
 
-import LWN.URI (filename)
+import LWN.URI (URL, filename)
 
-login_url :: URLString
+login_url :: URL
 login_url = "https://lwn.net/login"
 
 username_field :: String
@@ -44,11 +43,11 @@ default_curl_opts =
     -- And we don't want to use a DNS cache anyway.
     CurlDNSCacheTimeout 0,
 
-    -- Give it a little time...
-    CurlTimeout 45,
+    -- Follow redirects.
+    CurlFollowLocation True,
 
-    -- And let us know when things go wrong.
-    CurlVerbose True ]
+    -- Give it a little time...
+    CurlTimeout 45 ]
 
 
 make_cookie_jar :: IO FilePath
@@ -59,8 +58,8 @@ make_cookie_jar = do
   hClose out_handle -- We just want to create it for now.
   return out_path
 
-get_page :: Maybe FilePath -> URLString -> IO (Maybe String)
-get_page cookie_jar url =
+get_page :: Maybe FilePath -> URL -> IO (Either String String)
+get_page cookie_file url =
   withCurlDo $ do
     -- Create a curl instance.
     curl <- initialize
@@ -73,24 +72,25 @@ get_page cookie_jar url =
     -- Pull out the response code as a CurlCode.
     let code = respCurlCode resp
 
-    case code of
-      CurlOK -> return $ Just (respBody resp)
-      error_code -> do
-        hPutStrLn stderr ("HTTP Error: " ++ (show error_code))
+    return $
+      case code of
+        CurlOK -> Right (respBody resp)
+        error_code -> Left ("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
+      case cookie_file of
         Nothing -> []
-        Just cookies -> [ CurlCookieJar cookies ]
+        Just cookies -> [ CurlCookieFile cookies ]
 
     curl_opts = default_curl_opts ++ get_opts
 
 
-log_in :: FilePath -> String -> String -> IO Bool
+-- | Log in using curl. Store the resulting session cookies in the
+--   supplied file.
+log_in :: FilePath -> String -> String -> IO (Either String String)
 log_in cookie_jar username password =
   withCurlDo $ do
     -- Create a curl instance.
@@ -104,14 +104,13 @@ log_in cookie_jar username password =
     -- 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))
+    return $
+      case code of
+        CurlOK -> Right (respBody resp)
+        error_code -> Left $ "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
   where
     post_submit :: String
     post_submit = submit_field ++ "=Log+In"
@@ -143,7 +142,7 @@ log_in cookie_jar username password =
 --   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 :: URLString -> IO (Maybe FilePath)
+save_image :: URL -> IO (Maybe FilePath)
 save_image url = do
   it_exists <- doesFileExist url
   if it_exists then do
@@ -164,3 +163,22 @@ save_image url = do
           Right bs -> do
             B.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 <- 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