X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=src%2FMain.hs;h=6b18c8646d311bdcaef94042561299f1a5836241;hb=52e788e676ea2a67ad20b23d2e5c5b351f27b834;hp=e1cb91abdd0a704a05157622bf47806baa8bd24c;hpb=c3d8b2a27a41ae8dcf425a94bce7e093964c7616;p=dead%2Fhtsn.git

diff --git a/src/Main.hs b/src/Main.hs
index e1cb91a..6b18c86 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -36,43 +36,93 @@ import ExitCodes (
   exit_no_feed_hosts,
   exit_no_password,
   exit_no_username )
-import FeedHosts (FeedHosts(..))
+import Logging (
+  init_logging,
+  log_debug,
+  log_error,
+  log_info,
+  log_warning )
 import qualified OptionalConfiguration as OC (
   OptionalConfiguration(..),
   from_rc )
-import Terminal (hPutRedLn, putGreenLn)
+import Terminal (
+  display_debug,
+  display_error,
+  display_info,
+  display_sent,
+  display_warning )
+import TSN.FeedHosts (FeedHosts(..))
 import TSN.Xml (parse_xmlfid, xml_prologue)
 
 
-report_error :: String -> IO ()
-report_error = hPutRedLn stderr
-
+-- | 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
 
 
+-- | Takes a Configuration, and an XML document (as a String). The XML
+--   document is written to the output directory, as specified by the
+--   Configuration.
+--
+--   This can fail, but we don't purposefully throw any exceptions. If
+--   something goes wrong, we would rather log it and keep going.
+--
 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.
+--   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 :: Configuration -> Handle -> [String] -> IO ()
 loop !cfg !h !buffer = do
   line <- recv_line h
@@ -85,9 +135,10 @@ loop !cfg !h !buffer = do
     -- of its lines into one big string.
     let document = concat $ reverse buffer
     save_document cfg document
-    loop cfg h [line] -- empty the buffer before looping again
+    loop cfg h [line] -- Empty the buffer before looping again.
   else
-    loop cfg h (line : buffer) -- append line to the head of the buffer and loop
+    -- Append line to the head of the buffer and loop.
+    loop cfg h (line : buffer)
 
 
 log_in :: Configuration -> Handle -> IO ()
@@ -95,13 +146,13 @@ 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"
@@ -112,21 +163,23 @@ 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
@@ -150,18 +203,20 @@ connect_and_loop cfg host = do
       --
       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 []
 
 
 -- | A wrapper around threadDelay which takes seconds instead of
 --   microseconds as its argument.
+--
 thread_sleep :: Int -> IO ()
 thread_sleep seconds = do
   let microseconds = seconds * (10 ^ (6 :: Int))
   threadDelay microseconds
 
 
+-- | The entry point of the program.
 main :: IO ()
 main = do
   rc_cfg <- OC.from_rc
@@ -171,32 +226,45 @@ 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
   hSetBuffering stdout NoBuffering
 
+  -- Begin connecting to our feed hosts, starting with the first one.
   round_robin cfg 0
 
   where
+    -- | This is the top-level "loop forever" function. If an
+    --   exception is thrown, it will propagate up to this point, where
+    --   it will be logged and ignored in style.
+    --
+    --   Afterwards, we recurse (call ourself) again to loop more forevers.
+    --
     round_robin :: Configuration -> Int -> IO ()
     round_robin cfg feed_host_idx = do
       let hosts = get_feed_hosts $ feed_hosts cfg