diff options
Diffstat (limited to 'app/Main.hs')
| -rw-r--r-- | app/Main.hs | 307 |
1 files changed, 20 insertions, 287 deletions
diff --git a/app/Main.hs b/app/Main.hs index 31c9882..de77adc 100644 --- a/app/Main.hs +++ b/app/Main.hs @@ -7,302 +7,35 @@ {-# LANGUAGE TypeApplications #-} {-# LANGUAGE LambdaCase #-} {-# LANGUAGE RecordWildCards #-} - +{-# LANGUAGE DeriveGeneric #-} +{-# LANGUAGE DeriveAnyClass #-} +{-# LANGUAGE DerivingStrategies #-} +{-# LANGUAGE GeneralizedNewtypeDeriving #-} +-- | module Main where -import qualified Data.ByteString.Lazy as LB -import qualified Data.ByteString as BS -import qualified Data.Csv as CSV -import Data.Csv ((.:)) -import qualified Codec.Archive.Zip as Zip -import qualified Data.Vector as V -import Data.Vector (Vector) -import Text.Regex.TDFA ( (=~) ) -import Data.Text (Text) -import Fmt ( (+|), (|+) ) -import Data.Kind (Type) import Data.Maybe (fromMaybe, fromJust) -import Data.Functor ((<&>)) -import qualified Data.Time.Calendar.OrdinalDate as Day -import Data.Time.Calendar.OrdinalDate (Day) import Data.Time.Calendar.MonthDay (monthAndDayToDayOfYearValid) -import Data.Time (getCurrentTime, UTCTime (utctDay), dayOfWeek) -import Data.Time.Calendar.WeekDate (DayOfWeek(..)) - - -newtype Time = Time { toSeconds :: Int } - -instance CSV.FromField Time where - parseField f = do - text :: String <- CSV.parseField f - let (_,_,_,subs) = text =~ ("([0-9][0-9]?):([0-9][0-9]?):([0-9][0-9]?)" :: Text) - :: (String, String, String, [String]) - case subs of - [hh,mm,ss] -> pure $ Time $ read hh * 3600 + read mm * 60 + read ss - _ -> fail $ "encountered an invalid date: " <> text - -instance Show Time where - show (Time seconds) = "" - +|seconds `div` 3600|+":" - +|(seconds `mod` 3600) `div` 60|+":" - +|seconds `mod` 60|+"" - -instance CSV.FromField Day where - parseField f = do - text :: String <- CSV.parseField f - let (_,_,_,subs) = text =~ ("([0-9][0-9][0-9][0-9])([0-9][0-9])([0-9][0-9])" :: Text) - :: (String, String, String, [String]) - case subs of - [yyyy,mm,dd] -> do - let Just dayOfYear = monthAndDayToDayOfYearValid (Day.isLeapYear (read yyyy)) (read mm) (read dd) - pure $ Day.fromOrdinalDate (read yyyy) dayOfYear - _ -> fail $ "invalid date encountered: " <> show f - - - -data Depth = Shallow | Deep -type Switch :: Depth -> Type -> Type -> Type -type family Switch c a b where - Switch Deep a b = a - Switch Shallow a b = b - -type StationID = Text - --- | This is what's called a Stop in GTFS -data Station = Station - { stationId :: StationID - , stationName :: Text - , stationLat :: Float - , stationLon :: Float - } deriving Show - --- | This is what's called a stop time in GTFS -data Stop (deep :: Depth) = Stop - { stopTrip :: Int - , stopArrival :: Time - , stopDeparture :: Time - , stopStation:: Switch deep Station StationID - , stopSequence :: Int - } - -deriving instance Show (Stop 'Shallow) -deriving instance Show (Stop 'Deep) - - -data Calendar = Calendar - { calServiceId :: Text - , calMonday :: Bool - , calTuesday :: Bool - , calWednesday :: Bool - , calThursday :: Bool - , calFriday :: Bool - , calSaturday :: Bool - , calSunday :: Bool - , calStartDate :: Day - , calEndDate :: Day - } deriving Show - -data CalendarExceptionType = ServiceAdded | ServiceRemoved - deriving (Show, Eq) - -data CalendarDate = CalendarDate - { caldateServiceId :: Text - , caldateDate :: Day - , caldateExceptionType :: CalendarExceptionType - } deriving Show - -type TripID = Text -type ServiceID = Text - -data Trip = Trip - { tripRoute :: Text - , tripTripID :: TripID - , tripHeadsign :: Maybe Text - , tripShortName :: Maybe Text - , tripDirection :: Maybe Bool - -- NOTE: there's also block_id, which we're unlikely to ever need - , tripServiceId :: Text - -- , tripWheelchairAccessible :: Bool - -- , tripBikesAllowed :: Bool - , tripShapeId :: Text - } deriving Show - --- | helper function to find things in Vectors of things -tableLookup :: Eq key => (a -> key) -> key -> Vector a -> Maybe a -tableLookup proj key = V.find (\a -> proj a == key) - -instance CSV.FromNamedRecord Station where - parseNamedRecord r = Station - <$> r .: "stop_id" - <*> r .: "stop_name" - <*> r .: "stop_lat" - <*> r .: "stop_lon" - -instance CSV.FromNamedRecord (Stop 'Shallow) where - parseNamedRecord r = Stop - <$> r .: "trip_id" - <*> r .: "arrival_time" - <*> r .: "departure_time" - <*> r .: "stop_id" - <*> r .: "stop_sequence" - -instance CSV.FromNamedRecord Calendar where - parseNamedRecord r = Calendar - <$> r .: "service_id" - <*> intAsBool' r "monday" - <*> intAsBool' r "tuesday" - <*> intAsBool' r "wednesday" - <*> intAsBool' r "thursday" - <*> intAsBool' r "friday" - <*> intAsBool' r "saturday" - <*> intAsBool' r "sunday" - <*> r .: "start_date" - <*> r .: "end_date" - -intAsBool :: CSV.NamedRecord -> BS.ByteString -> CSV.Parser (Maybe Bool) -intAsBool r field = do - int <- r .: field - pure $ case int :: Int of - 1 -> Just True - 0 -> Just False - _ -> Nothing - -intAsBool' :: CSV.NamedRecord -> BS.ByteString -> CSV.Parser Bool -intAsBool' r field = intAsBool r field >>= maybe - (fail "unexpected value for a boolean.") - pure - - -instance CSV.FromNamedRecord CalendarDate where - parseNamedRecord r = CalendarDate - <$> r .: "service_id" - <*> r .: "date" - <*> do - int <- r .: "exception_type" - case int :: Int of - 1 -> pure ServiceAdded - 2 -> pure ServiceRemoved - _ -> fail $ "unexpected value in exception_type: "+|int|+"." - - -instance CSV.FromNamedRecord Trip where - parseNamedRecord r = Trip - <$> r .: "route_id" - <*> r .: "trip_id" - <*> r .: "trip_headsign" - <*> r .: "trip_short_name" - <*> intAsBool r "direction_id" - <*> r .: "service_id" - -- NOTE: these aren't booleans but triple-values - -- <*> intAsBool r "wheelchair_accessible" - -- <*> intAsBool r "bikes_allowed" - <*> r .: "shape_id" - -data GTFS (depth :: Depth) = GTFS - { stations :: Vector Station - , stops :: Vector (Stop depth) - , trips :: Vector Trip - , calendar :: Maybe (Vector Calendar) - , calendarDates :: Maybe (Vector CalendarDate) - } - -deriving instance Show (GTFS Shallow) -deriving instance Show (GTFS Deep) - -class Loadable depth where - loadGtfs :: FilePath -> IO (GTFS depth) - -instance Loadable Shallow where - loadGtfs path = do - zip <- Zip.toArchive <$> LB.readFile "./gtfs.zip" - GTFS <$> decodeTable' "stops.txt" zip - <*> decodeTable' "stop_times.txt" zip - <*> decodeTable' "trips.txt" zip - <*> decodeTable "calendar.txt" zip - <*> decodeTable "calendar_dates.txt" zip - where - decodeTable :: CSV.FromNamedRecord a => FilePath -> Zip.Archive -> IO (Maybe (Vector a)) - decodeTable path zip = do - case Zip.findEntryByPath path zip of - Nothing -> pure Nothing - Just csv -> case CSV.decodeByName (Zip.fromEntry csv) of - Left err -> error "blah" - Right (_,v :: a) -> pure (Just v) - decodeTable' path zip = - decodeTable path zip >>= \case - Nothing -> fail $ "required file "+|path|+" not found in gtfs.zip" - Just a -> pure a - -instance Loadable Deep where - loadGtfs path = do - shallow <- loadGtfs @Shallow path - stops' <- V.mapM (pushStop (stations shallow)) (stops shallow) - pure $ shallow { stops = stops' } - where - pushStop :: Vector Station -> Stop Shallow -> IO (Stop Deep) - pushStop stations stop = do - station <- case tableLookup stationId (stopStation stop) stations of - Just a -> pure a - Nothing -> fail $ "station with id "+|stopStation stop|+"is mentioned but not defined." - pure $ stop { stopStation = station } - - - -servicesOnDay :: GTFS Deep -> Day -> Vector ServiceID -servicesOnDay GTFS{..} day = - fmap caldateServiceId added <> V.filter notCancelled regular - where (added,removed) = case calendarDates of - Nothing -> (mempty,mempty) - Just exs -> - V.partition (\cd -> caldateExceptionType cd == ServiceAdded) - $ V.filter (\cd -> caldateDate cd == day) exs - regular = case calendar of - Nothing -> mempty - Just cs -> V.mapMaybe (\cal -> if isRunning cal then Just (calServiceId cal) else Nothing) cs - where isRunning Calendar{..} = - day >= calStartDate && - day <= calEndDate && - case weekday of - Monday -> calMonday - Tuesday -> calTuesday - Wednesday -> calWednesday - Thursday -> calThursday - Friday -> calFriday - Saturday -> calSaturday - Sunday -> calSunday - weekday = dayOfWeek day - notCancelled serviceID = - null (tableLookup caldateServiceId serviceID removed) +import qualified Data.Time.Calendar.OrdinalDate as Day +import qualified Data.ByteString.Lazy as LB +import qualified Data.Aeson as A +import Network.Wai.Middleware.RequestLogger (OutputFormat (..), + RequestLoggerSettings (..), + mkRequestLogger) +import Network.Wai.Handler.Warp (run) +import Data.Default.Class (def) -tripsOfService :: GTFS Deep -> ServiceID -> Vector Trip -tripsOfService GTFS{..} serviceId = - V.filter (\trip -> tripServiceId trip == serviceId ) trips +import GTFS +import Server main :: IO () main = do gtfs <- loadGtfs @Deep "./gtfs.zip" - - -- today <- getCurrentTime <&> utctDay - -- print (calendar gtfs) - let today = Day.fromOrdinalDate 2022 (fromJust $ monthAndDayToDayOfYearValid False 6 6) - print today - - putStrLn "trips today:" - print (fmap (tripsOfService gtfs) (servicesOnDay gtfs today)) - - -{- -TODO: -there should be a basic API allowing the questions: - - what are the next trips leaving from $station? (or $geolocation?) - - all stops of a given tripID - -then the "ingress" API: - - train ping (location, estimated delay, etc.) - - cancel trip - - add trip? - --} + app <- application gtfs + loggerMiddleware <- mkRequestLogger + $ def { outputFormat = Detailed True } + putStrLn "starting server …" + run 4000 (loggerMiddleware app) |