X-Git-Url: http://gitweb.michael.orlitzky.com/?p=dead%2Flwn-epub.git;a=blobdiff_plain;f=src%2FLWN%2FHTTP.hs;h=4cfcb04bfbc389c6c75f539516249ee91145b882;hp=c74248ba9dca05bdcc54c2417758906ecd021212;hb=4220827f62d772d7edcbdcc1c2f13d6c2eb5f534;hpb=79eb04e3c84bd9514659d0d52c2e862959647aa6

diff --git a/src/LWN/HTTP.hs b/src/LWN/HTTP.hs
index c74248b..4cfcb04 100644
--- a/src/LWN/HTTP.hs
+++ b/src/LWN/HTTP.hs
@@ -1,26 +1,28 @@
+{-# LANGUAGE DoAndIfThenElse #-}
+
 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 (getTemporaryDirectory)
-import System.IO (hPutStrLn, stderr)
-import System.IO.Temp (openBinaryTempFile)
+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
@@ -37,20 +39,27 @@ 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,
 
-    -- 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
+make_cookie_jar = do
+  temp_dir <- getTemporaryDirectory
+  let file_name_template = "lwn-epub-cookies.txt"
+  (out_path, out_handle) <- openTempFile temp_dir file_name_template
+  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
@@ -58,29 +67,30 @@ get_page cookie_jar url =
     -- 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 <- do_curl_ curl url curl_opts :: IO CurlResponse
 
     -- 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.
@@ -94,14 +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"
@@ -113,7 +122,7 @@ log_in cookie_jar username password =
     post_password = password_field ++ "=" ++ password
 
     post_data :: [String]
-    post_data = [post_username, post_password]
+    post_data = [post_username, post_password, post_submit]
 
     post_opts :: [CurlOption]
     post_opts =
@@ -121,7 +130,7 @@ log_in cookie_jar username password =
         CurlCookieJar cookie_jar,
         CurlPost True,
         CurlPostFields post_data ]
-        
+
     curl_opts :: [CurlOption]
     curl_opts = default_curl_opts ++ post_opts
 
@@ -133,19 +142,43 @@ 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
-  let fn = filename url
-  case fn of
-    Nothing -> return Nothing
-    Just file -> do
-      temp_dir <- getTemporaryDirectory
-      (out_path, out_handle) <- openBinaryTempFile temp_dir file
-      result <- openURI url
-      case result of
-        Left err -> do
-          hPutStrLn stderr ("HTTP Error: " ++ err)
-          return Nothing
-        Right bs -> do
-          B.hPut out_handle bs
-          return $ Just out_path
+  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
+        result <- openURI url
+        case result of
+          Left err -> do
+            hPutStrLn stderr ("HTTP Error: " ++ err)
+            return Nothing
+          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