+{-# LANGUAGE DoAndIfThenElse #-}
+
module LWN.HTTP
where
+import qualified Data.ByteString as B (hPut)
+
import Network.Curl (
CurlCode(..),
CurlOption(..),
respCurlCode,
withCurlDo
)
-import System.IO (hPutStrLn, stderr)
+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)
login_url :: URLString
login_url = "https://lwn.net/login"
CurlVerbose True ]
+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 =
-- 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
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 =
curl_opts :: [CurlOption]
curl_opts = default_curl_opts ++ post_opts
+
+
+-- | 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 :: URLString -> 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
+ 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