Logging.Aeson

Documentation

By using Aeson, we can decode json string into Manager.

A basic Manager json format:

  {
    "loggers": {"root": {}, "MyLogger": {}},
    "handlers": {"console": {}, "file": {}},
    "formatters": {"default": "format", "simple": "format"},
    "disabled": false,
    "catchUncaughtException": true
  }

In practice, a set of handlers share a formatter, and other handlers share another one, so we define all the formatters in a map, handler refernces the formatter throught its key.

So as handlers, sinks may share same handlers.

Examples of Formatter json

See Format of vformat package for more information about formatting.

  "{message}"
  "{logger} {level}: {message}"
  "{logger:<20.20s} {level:<8s}: {message}"
  "{asctime:%Y-%m-%dT%H:%M:%S%6Q%z} - {level} - {logger}] {message}"

Examples of Handler json

Note: Besides some common field, handler's other fields depend on its type.

  -- StreamHandler
  {
    "type": "StreamHandler",
    "stream": "stderr",
    "level": "DEBUG",
    "filterer": ["Package.Module.Submodule"],
    "formatter": "default",
  }

  -- FileHandler
  {
    "type": "FileHandler",
    "file": "./default.log",
    "level": "INFO",
    "filterer": [],
    "formatter": "simple",
  }

Examples of Logger (Sink) json

  -- a standard format
  {
    "level": "DEBUG",
    "filterer": ["Package.Module.Submodule"],
    "handlers": ["console"],
    "propagate": true,
    "disabled": false
  }

  -- this example is equivalent to the first
  {
    "level": "DEBUG",
    "filterer": ["Package.Module.Submodule"],
    "handlers": ["console"]
  }

  -- another example
  {
    "level": "INFO",
    "handlers": ["console", "file"],
    "propagate": false
  }

Orphan instances

FromJSON Format1

Methods

parseJSON :: Value -> Parser Format1

parseJSONList :: Value -> Parser [Format1]

FromJSON Level

Methods

parseJSON :: Value -> Parser Level

parseJSONList :: Value -> Parser [Level]

FromJSON Filter

Methods

parseJSON :: Value -> Parser Filter

parseJSONList :: Value -> Parser [Filter]

FromJSON StreamHandler

Methods

parseJSON :: Value -> Parser StreamHandler

parseJSONList :: Value -> Parser [StreamHandler]

FromJSON Sink

Methods

parseJSON :: Value -> Parser Sink

parseJSONList :: Value -> Parser [Sink]

FromJSON (IO SomeHandler)

Methods

parseJSON :: Value -> Parser (IO SomeHandler)

parseJSONList :: Value -> Parser [IO SomeHandler]

FromJSON (IO Manager)

Methods

parseJSON :: Value -> Parser (IO Manager)

parseJSONList :: Value -> Parser [IO Manager]

FromJSON (IO FileHandler)

Methods

parseJSON :: Value -> Parser (IO FileHandler)

parseJSONList :: Value -> Parser [IO FileHandler]

FromJSON (Map String Format1 -> IO SomeHandler)

Methods

parseJSON :: Value -> Parser (Map String Format1 -> IO SomeHandler)

parseJSONList :: Value -> Parser [Map String Format1 -> IO SomeHandler]

FromJSON (String -> Map String SomeHandler -> Sink)

Methods

parseJSON :: Value -> Parser (String -> Map String SomeHandler -> Sink)

parseJSONList :: Value -> Parser [String -> Map String SomeHandler -> Sink]