1 #!/usr/bin/env runhaskell
4 -- I am truly sorry. I would have used servant, but it failed to install. --
5 -- I would have used sqeletto, but got thrown back by depencencies. --
6 -- I would have used some standard config file parser but they are all --
7 -- overkills. This program is a very quick and dirty hack. --
10 {-# LANGUAGE OverloadedStrings #-}
21 import Database.MySQL.Simple
23 main = runCGI $ handleErrors cgiMain
25 cgiMain :: CGI CGIResult
27 conf <- liftIO $ readConf "/etc/watermeter.db"
28 conn <- liftIO $ connect defaultConnectInfo { connectHost = host conf
29 , connectUser = user conf
30 , connectPassword = pass conf
31 , connectDatabase = dbnm conf
33 today <- liftIO getClockTime
34 let tomorrow = addToClockTime (noTimeDiff {tdDay = 1}) today
35 daystart x = (toUTCTime x) { ctHour = 0, ctMin = 0
36 , ctSec = 0, ctPicosec = 0}
37 dtstr x = formatCalendarTime defaultTimeLocale "%Y-%m-%d %H:%M:%S" x
38 dlo = dtstr $ daystart today
39 dhi = dtstr $ daystart tomorrow
42 -- _ <- liftIO $ putStrLn $ " dlo=" ++ show dlo ++ " ilo=" ++ show ilo
43 -- ++ " dhi=" ++ show dhi ++ " ihi=" ++ show ihi
44 let slo = fromMaybe dlo ilo :: String
45 shi = fromMaybe dhi ihi :: String
46 [(olo, ohi)] <- liftIO $ query conn "select unix_timestamp(?), unix_timestamp(?);"
48 cold <- liftIO $ query conn
49 "select unix_timestamp(timestamp) as time, value+adj as value from \
50 \(select c.timestamp timestamp, c.value value, \
51 \(select sum(value) from coldadj a where a.timestamp <= c.timestamp \
52 \) adj from coldcnt c where timestamp between ? and ? \
53 \) t order by timestamp;" (slo, shi)
54 hot <- liftIO $ query conn
55 "select unix_timestamp(timestamp) as time, value+adj as value from \
56 \(select c.timestamp timestamp, c.value value, \
57 \(select sum(value) from hotadj a where a.timestamp <= c.timestamp \
58 \) adj from hotcnt c where timestamp between ? and ? \
59 \) t order by timestamp;" (slo, shi)
60 [(ccold, chot)] <- liftIO $ query_ conn
61 "select lcold+acold as cold, lhot+ahot as hot from \
62 \(select value as lcold from coldcnt order by timestamp desc limit 1) cc, \
63 \(select sum(value) as acold from coldadj) ac, \
64 \(select value as lhot from hotcnt order by timestamp desc limit 1) ch, \
65 \(select sum(value) as ahot from hotadj) ah;"
66 _ <- liftIO $ close conn
68 setHeader "Content-type" "application/json"
69 output $ "{\"range\": {\"lo\": " ++ show (floor (olo :: (Ratio Integer)))
70 ++ ", \"hi\": " ++ show (floor (ohi :: (Ratio Integer)))
71 ++ "}, \"current\": {\"cold\": " ++ show (floor (ccold :: (Ratio Integer)))
72 ++ ", \"hot\": " ++ show (floor (chot :: (Ratio Integer)))
73 ++ "}, \"cold\": [" ++ showjson cold
74 ++ "], \"hot\": [" ++ showjson hot ++ "]}\n"
76 showjson :: [(Int, (Ratio Integer))] -> String
77 showjson l = intercalate "," $ map (\(t, c) -> "[" ++ show t ++ "," ++ show (floor c) ++ "]") l
79 data Conf = Conf { host :: String
85 readConf :: String -> IO Conf
87 readFile fn >>= return . (foldr parseLine (Conf "" "" "" "")) . lines
89 parseLine :: String -> Conf -> Conf
94 "host" -> sum { host = v }
95 "user" -> sum { user = v }
96 "password" -> sum { pass = v }
97 "database" -> sum { dbnm = v }
98 _ -> error $ "bad key in config line \"" ++ l ++ "\""
99 _ -> error $ "bad config line \"" ++ l ++ "\""