web/Settings.hs

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