Monadic correlated log events

Latest on Hackage:6.1.5

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BSD3 licensed by Michael Adlai Arnold
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Monadic correlated log events!

To Use:

  • given a data type: ` data UserSpec = UserSpec { email :: Email , password :: Text , name :: Text } deriving (Eq, Show, Generic) `

    we can create an instance of ToLog: ` instance ToLog UserSpec where toLog UserSpec{email, name} = dictionary [ pair "email" email , pair "password" Redacted , pair "name" name ] `

    and derive JSON instances of that: ` deriveJSON defaultOptions ''UserSpec `

    which can then be logged inside a monad: ` foo = do let jimbo = UserSpec (Email "" ...) logJSON $ Event (CorrelationId 0) (EventId 0) "User" (toLog jimbo) return jimbo `

  • you must force stdout to flush after each line, or logs won't appear in a timely manner: call Graflog.Console.enableStdoutLineBuffering at the top of your main function.

  • CorrelationId and EventId generation are not yet supported, so you must create an event manually: - inside do notation: let event = Event (CorrelationId 0) (EventId 0) - followed at some point by: logJSON $ event (Action "some kind of metadata") (toLog dataToLog)

To Do:

  • CorrelationId and EventId generation
  • Generic derivation of ToLog / ToJSON instances
  • Support for non-JSON logging?
Used by 1 package:
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