X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FMain.hs;h=f2febcb95ced479f1b965e2ea96ef21bf4ab7326;hb=eb1187607a616b36bb446650dc141019345eed8f;hp=1b7458fe880c83463038abbc2de73be16f3d09ff;hpb=a2c2a1a6865be7b4cd17fb72de635bb9385728b9;p=dead%2Fhtsn.git diff --git a/src/Main.hs b/src/Main.hs index 1b7458f..f2febcb 100644 --- a/src/Main.hs +++ b/src/Main.hs @@ -4,19 +4,19 @@ module Main where -import Control.Concurrent (threadDelay) -import Control.Exception.Base (bracket) -import Control.Monad (when) -import Data.List (isPrefixOf) -import Data.Maybe (isNothing) -import Data.Monoid ((<>)) +import Control.Concurrent ( threadDelay ) +import Control.Exception.Base ( bracket ) +import Control.Monad ( when ) +import Data.List ( isPrefixOf ) +import Data.Maybe ( isNothing ) +import Data.Monoid ( (<>) ) import Network ( connectTo, PortID (PortNumber) ) -import System.Console.CmdArgs (def) -import System.Directory (doesFileExist) -import System.Exit (ExitCode(..), exitWith) -import System.FilePath (()) +import System.Console.CmdArgs ( def ) +import System.Directory ( doesFileExist ) +import System.Exit ( ExitCode(..), exitWith ) +import System.FilePath ( () ) import System.IO ( BufferMode (NoBuffering), Handle, @@ -27,30 +27,70 @@ import System.IO ( hSetBuffering, stderr, stdout ) -import System.IO.Error (catchIOError) -import System.Timeout (timeout) +import System.IO.Error ( catchIOError ) +import System.Timeout ( timeout ) -import CommandLine (get_args) -import Configuration (Configuration(..), merge_optional) +import CommandLine ( get_args ) +import Configuration ( Configuration(..), merge_optional ) import ExitCodes ( exit_no_feed_hosts, exit_no_password, exit_no_username ) +import Logging ( + init_logging, + log_debug, + log_error, + log_info, + log_warning ) import qualified OptionalConfiguration as OC ( OptionalConfiguration(..), from_rc ) -import Terminal (putGreenLn, report_error) -import TSN.FeedHosts (FeedHosts(..)) -import TSN.Xml (parse_xmlfid, xml_prologue) - - --- | Receive a single line of text from a Handle, echoing it to stdout --- in the process. +import Terminal ( + display_debug, + display_error, + display_info, + display_sent, + display_warning ) +import TSN.FeedHosts ( FeedHosts(..) ) +import TSN.Xml ( parse_xmlfid ) + + +-- | Warning! This does not automatically append a newline. The output +-- is displayed/logged as-is, for, you know, debug purposes. +report_debug :: String -> IO () +report_debug s = do + display_debug s + log_debug s + +report_error :: String -> IO () +report_error s = do + display_error $ "ERROR: " ++ s + log_error s + +report_info :: String -> IO () +report_info s = do + display_info s + log_info s + +-- | Warning! This does not automatically append a newline. +report_sent :: String -> IO () +report_sent s = do + display_sent s + log_debug s + +report_warning :: String -> IO () +report_warning s = do + display_warning $ "WARNING: " ++ s + log_warning s + + +-- | Receive a single line of text from a Handle, and send it to the +-- debug log. -- recv_line :: Handle -> IO String recv_line h = do line <- hGetLine h - putStrLn line + report_debug (line ++ "\n") return line @@ -65,39 +105,50 @@ save_document :: Configuration -> String -> IO () save_document cfg doc = case maybe_path of Nothing -> - report_error "ERROR: document missing XML_File_ID element." + report_error "Document missing XML_File_ID element." Just path -> do already_exists <- doesFileExist path when already_exists $ do - let msg = "WARNING: file " ++ path ++ " already exists. Overwriting." - report_error msg + let msg = "File " ++ path ++ " already exists, overwriting." + report_warning msg writeFile path doc + report_info $ "Wrote file: " ++ path ++ "." where xmlfid = fmap show (parse_xmlfid doc) filename = fmap (++ ".xml") xmlfid maybe_path = fmap ((output_directory cfg) ) filename --- | Loop forever, writing the buffer to file whenever a new XML --- prologue is seen. This is the low-level "loop forever" function --- that we stay in as long as we are connected to one feed. +-- | Loop forever, writing the buffer to file whenever a +-- tag is seen. This is the low-level "loop forever" function that +-- we stay in as long as we are connected to one feed. +-- +-- The documentation at +-- states +-- that \ will always be the root element of the XML +-- documents, and \ will be the final line transmitted +-- for a given document. We therefore rely on this to simplify +-- processing. -- loop :: Configuration -> Handle -> [String] -> IO () loop !cfg !h !buffer = do line <- recv_line h + let new_buffer = line : buffer - if (xml_prologue `isPrefixOf` line && not (null buffer)) + -- Use isPrefixOf to avoid line-ending issues. Hopefully they won't + -- send invalid junk (on the same line) after closing the root + -- element. + if "" `isPrefixOf` line then do - -- This is the beginning of a new document, and we have an "old" - -- one to save. The buffer is in reverse (newest first) order, - -- though, so we have to reverse it first. We then concatenate all - -- of its lines into one big string. - let document = concat $ reverse buffer + -- The buffer is in reverse (newest first) order, though, so we + -- have to reverse it first. We then concatenate all of its lines + -- into one big string. + let document = concat $ reverse new_buffer save_document cfg document - loop cfg h [line] -- empty the buffer before looping again + loop cfg h [] -- Empty the buffer before looping again. else - -- append line to the head of the buffer and loop - loop cfg h (line : buffer) + -- Append line to the head of the buffer and loop. + loop cfg h new_buffer log_in :: Configuration -> Handle -> IO () @@ -105,13 +156,13 @@ log_in cfg h = do prompt1 <- recv_prompt h if prompt1 /= username_prompt then - report_error "ERROR: didn't receive username prompt." + report_error "Didn't receive username prompt." else do send_line h (username cfg) prompt2 <- recv_prompt h if prompt2 /= password_prompt then - report_error "ERROR: didn't receive password prompt." + report_error "Didn't receive password prompt." else do send_line h (password cfg) _ <- recv_line h -- "The Sports Network" @@ -122,21 +173,23 @@ log_in cfg h = do send_line :: Handle -> String -> IO () send_line h' s = do - hPutStr h' (s ++ "\r\n") - putGreenLn s + let line = s ++ "\r\n" + hPutStr h' line + display_sent line recv_chars :: Int -> Handle -> IO String recv_chars n h' = do s <- sequence [ hGetChar h' | _ <- [1..n] ] - putStr s + report_debug s return s recv_prompt :: Handle -> IO String recv_prompt = recv_chars 10 + connect_and_loop :: Configuration -> String -> IO () connect_and_loop cfg host = do - putStrLn $ "Connecting to " ++ host ++ "..." + report_info $ "Connecting to " ++ host ++ "..." bracket acquire_handle release_handle action return () where @@ -155,12 +208,18 @@ connect_and_loop cfg host = do -- -- If we dump the packets with tcpdump, it looks like their -- software is getting confused: they send us some XML in - -- the middle of the log-in procedure. In any case, the easiest - -- fix is to disconnect and try again. + -- the middle of the log-in procedure. + -- + -- On the other hand, the documentation at + -- + -- states that you can only make one connection per username to + -- a given host. So maybe they're simply rejecting the username + -- in an unfriendly fashion. In any case, the easiest fix is to + -- disconnect and try again. -- login_worked <- timeout five_seconds $ log_in cfg h case login_worked of - Nothing -> putStrLn "Login timed out (5s)." + Nothing -> report_info "Login timed out (5s)." Just _ -> loop cfg h [] @@ -183,26 +242,30 @@ main = do -- prefering the command-line ones. let opt_config = rc_cfg <> cmd_cfg - -- This is necessary because if the user specifies an empty list of + -- Update a default config with any options that have been set in + -- either the config file or on the command-line. We initialize + -- logging before the missing parameter checks below so that we can + -- log the errors. + let cfg = (def :: Configuration) `merge_optional` opt_config + init_logging (syslog cfg) + + -- Check the optional config for missing required options. This is + -- necessary because if the user specifies an empty list of -- hostnames in e.g. the config file, we want to bail rather than - -- fall back on the default list (which gets merged from a - -- Configuration below). + -- fall back on the default list (which was merged from a default + -- Configuration above). when (null $ get_feed_hosts (OC.feed_hosts opt_config)) $ do - report_error "ERROR: no feed hosts supplied." + report_error "No feed hosts supplied." exitWith (ExitFailure exit_no_feed_hosts) when (isNothing (OC.password opt_config)) $ do - report_error "ERROR: no password supplied." + report_error "No password supplied." exitWith (ExitFailure exit_no_password) when (isNothing (OC.username opt_config)) $ do - report_error "ERROR: no username supplied." + report_error "No username supplied." exitWith (ExitFailure exit_no_username) - -- Finally, update a default config with any options that have been - -- set in either the config file or on the command-line. - let cfg = (def :: Configuration) `merge_optional` opt_config - -- This may be superstition (and I believe stderr is unbuffered), -- but it can't hurt. hSetBuffering stderr NoBuffering @@ -223,5 +286,5 @@ main = do let hosts = get_feed_hosts $ feed_hosts cfg let host = hosts !! feed_host_idx catchIOError (connect_and_loop cfg host) (report_error . show) - thread_sleep 10 -- Wait 10s before attempting to reconnect. + thread_sleep 5 -- Wait 5s before attempting to reconnect. round_robin cfg $ (feed_host_idx + 1) `mod` (length hosts)