class SemanticLogger::Formatters::Json

def call(log, logger)

Returns log messages in JSON format 
def call(log, logger)
  super.to_json
end

def initialize(time_format: :iso_8601, time_key: :timestamp, **args)

Default JSON time format is ISO8601 
def initialize(time_format: :iso_8601, time_key: :timestamp, **args)
  super
end