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 #-}
20 import Database.MySQL.Simple
22 main = runCGI $ handleErrors cgiMain
24 cgiMain :: CGI CGIResult
26 conf <- liftIO $ readConf "/etc/watermeter.db"
27 conn <- liftIO $ connect defaultConnectInfo { connectHost = host conf
28 , connectUser = user conf
29 , connectPassword = pass conf
30 , connectDatabase = dbnm conf
32 today <- liftIO getClockTime
33 let tomorrow = addToClockTime (noTimeDiff {tdDay = 1}) today
34 daystart x = (toUTCTime x) { ctHour = 0, ctMin = 0
35 , ctSec = 0, ctPicosec = 0}
36 dtstr x = formatCalendarTime defaultTimeLocale "%Y-%m-%d %H:%M:%S" x
37 dlo = dtstr $ daystart today
38 dhi = dtstr $ daystart tomorrow
41 -- _ <- liftIO $ putStrLn $ " dlo=" ++ show dlo ++ " ilo=" ++ show ilo
42 -- ++ " dhi=" ++ show dhi ++ " ihi=" ++ show ihi
43 let slo = fromMaybe dlo ilo :: String
44 shi = fromMaybe dhi ihi :: String
45 [(olo, ohi)] <- liftIO $ query conn "select to_seconds(?), to_seconds(?);"
47 cold <- liftIO $ query conn
48 "select to_seconds(timestamp) as time, value+adj as value from \
49 \(select c.timestamp timestamp, c.value value, \
50 \(select sum(value) from coldadj a where a.timestamp <= c.timestamp \
51 \) adj from coldcnt c \
52 \where timestamp between ? and ? order by timestamp \
54 hot <- liftIO $ query conn
55 "select to_seconds(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 \
59 \where timestamp between ? and ? order by timestamp \
61 [(ccold, chot)] <- liftIO $ query_ conn
62 "select lcold+acold as cold, lhot+ahot as hot from \
63 \(select value as lcold from coldcnt order by timestamp desc limit 1) cc, \
64 \(select sum(value) as acold from coldadj) ac, \
65 \(select value as lhot from hotcnt order by timestamp desc limit 1) ch, \
66 \(select sum(value) as ahot from hotadj) ah;"
67 _ <- liftIO $ close conn
69 setHeader "Content-type" "application/json"
70 output $ "{\"range\": {\"lo\": " ++ show (olo :: Int)
71 ++ ", \"hi\": " ++ show (ohi :: Int)
72 ++ "}, \"current\": {\"cold\": " ++ show (floor (ccold :: Double))
73 ++ ", \"hot\": " ++ show (floor (chot :: Double))
74 ++ "}}, \"cold\": [" ++ showjson cold
75 ++ "], \"hot\": [" ++ showjson hot ++ "]}\n"
77 showjson :: [(Int, Double)] -> String
78 showjson l = intercalate "," $ map (\(t, c) -> "[" ++ show t ++ "," ++ show (floor c) ++ "]") l
80 data Conf = Conf { host :: String
86 readConf :: String -> IO Conf
88 readFile fn >>= return . (foldr parseLine (Conf "" "" "" "")) . lines
90 parseLine :: String -> Conf -> Conf
95 "host" -> sum { host = v }
96 "user" -> sum { user = v }
97 "password" -> sum { pass = v }
98 "database" -> sum { dbnm = v }
99 _ -> error $ "bad key in config line \"" ++ l ++ "\""
100 _ -> error $ "bad config line \"" ++ l ++ "\""