web/Settings.hs

   1 {-# LANGUAGE CPP #-}
   2 {-# LANGUAGE TemplateHaskell #-}
   3
   4 -- | Settings are centralized, as much as possible, into this file. This
   5 -- includes database connection settings, static file locations, etc.
   6 -- In addition, you can configure a number of different aspects of Yesod
   7 -- by overriding methods in the Yesod typeclass. That instance is
   8 -- declared in the Foundation.hs file.
   9 module Settings where
  10
  11 import ClassyPrelude.Yesod
  12 import Control.Exception           (throw)
  13 import Data.Aeson                  (Result (..), fromJSON, withObject, (.!=),
  14                                     (.:?))
  15 import Data.FileEmbed              (embedFile)
  16 import Data.Yaml                   (decodeEither')
  17 import Database.Persist.Sqlite     (SqliteConf)
  18 import Language.Haskell.TH.Syntax  (Exp, Name, Q)
  19 import Network.Wai.Handler.Warp    (HostPreference)
  20 import Yesod.Default.Config2       (applyEnvValue, configSettingsYml)
  21 import Yesod.Default.Util          (WidgetFileSettings, widgetFileNoReload,
  22                                     widgetFileReload)
  23
  24 -- | Runtime settings to configure this application. These settings can be
  25 -- loaded from various sources: defaults, environment variables, config files,
  26 -- theoretically even a database.
  27 data AppSettings = AppSettings
  28     { appStaticDir              :: String
  29     -- ^ Directory from which to serve static files.
  30     , appDatabaseConf           :: SqliteConf
  31     -- ^ Configuration settings for accessing the database.
  32     , appRoot                   :: Text
  33     -- ^ Base for all generated URLs.
  34     , appHost                   :: HostPreference
  35     -- ^ Host/interface the server should bind to.
  36     , appPort                   :: Int
  37     -- ^ Port to listen on
  38     , appIpFromHeader           :: Bool
  39     -- ^ Get the IP address from the header when logging. Useful when sitting
  40     -- behind a reverse proxy.
  41
  42     , appDetailedRequestLogging :: Bool
  43     -- ^ Use detailed request logging system
  44     , appShouldLogAll           :: Bool
  45     -- ^ Should all log messages be displayed?
  46     , appReloadTemplates        :: Bool
  47     -- ^ Use the reload version of templates
  48     , appMutableStatic          :: Bool
  49     -- ^ Assume that files in the static dir may change after compilation
  50     , appSkipCombining          :: Bool
  51     -- ^ Perform no stylesheet/script combining
  52
  53     -- Example app-specific configuration values.
  54     , appCopyright              :: Text
  55     -- ^ Copyright text to appear in the footer of the page
  56     , appAnalytics              :: Maybe Text
  57     -- ^ Google Analytics code
  58     }
  59
  60 instance FromJSON AppSettings where
  61     parseJSON = withObject "AppSettings" $ \o -> do
  62         let defaultDev =
  63 #if DEVELOPMENT
  64                 True
  65 #else
  66                 False
  67 #endif
  68         appStaticDir              <- o .: "static-dir"
  69         appDatabaseConf           <- o .: "database"
  70         appRoot                   <- o .: "approot"
  71         appHost                   <- fromString <$> o .: "host"
  72         appPort                   <- o .: "port"
  73         appIpFromHeader           <- o .: "ip-from-header"
  74
  75         appDetailedRequestLogging <- o .:? "detailed-logging" .!= defaultDev
  76         appShouldLogAll           <- o .:? "should-log-all"   .!= defaultDev
  77         appReloadTemplates        <- o .:? "reload-templates" .!= defaultDev
  78         appMutableStatic          <- o .:? "mutable-static"   .!= defaultDev
  79         appSkipCombining          <- o .:? "skip-combining"   .!= defaultDev
  80
  81         appCopyright              <- o .: "copyright"
  82         appAnalytics              <- o .:? "analytics"
  83
  84         return AppSettings {..}
  85
  86 -- | Settings for 'widgetFile', such as which template languages to support and
  87 -- default Hamlet settings.
  88 --
  89 -- For more information on modifying behavior, see:
  90 --
  91 -- https://github.com/yesodweb/yesod/wiki/Overriding-widgetFile
  92 widgetFileSettings :: WidgetFileSettings
  93 widgetFileSettings = def
  94
  95 -- | How static files should be combined.
  96 combineSettings :: CombineSettings
  97 combineSettings = def
  98
  99 -- The rest of this file contains settings which rarely need changing by a
 100 -- user.
 101
 102 widgetFile :: String -> Q Exp
 103 widgetFile = (if appReloadTemplates compileTimeAppSettings
 104                 then widgetFileReload
 105                 else widgetFileNoReload)
 106               widgetFileSettings
 107
 108 -- | Raw bytes at compile time of @config/settings.yml@
 109 configSettingsYmlBS :: ByteString
 110 configSettingsYmlBS = $(embedFile configSettingsYml)
 111
 112 -- | @config/settings.yml@, parsed to a @Value@.
 113 configSettingsYmlValue :: Value
 114 configSettingsYmlValue = either throw id $ decodeEither' configSettingsYmlBS
 115
 116 -- | A version of @AppSettings@ parsed at compile time from @config/settings.yml@.
 117 compileTimeAppSettings :: AppSettings
 118 compileTimeAppSettings =
 119     case fromJSON $ applyEnvValue False mempty configSettingsYmlValue of
 120         Error e -> error e
 121         Success settings -> settings
 122
 123 -- The following two functions can be used to combine multiple CSS or JS files
 124 -- at compile time to decrease the number of http requests.
 125 -- Sample usage (inside a Widget):
 126 --
 127 -- > $(combineStylesheets 'StaticR [style1_css, style2_css])
 128
 129 combineStylesheets :: Name -> [Route Static] -> Q Exp
 130 combineStylesheets = combineStylesheets'
 131     (appSkipCombining compileTimeAppSettings)
 132     combineSettings
 133
 134 combineScripts :: Name -> [Route Static] -> Q Exp
 135 combineScripts = combineScripts'
 136     (appSkipCombining compileTimeAppSettings)
 137     combineSettings