Format LogEvents as JSON

Source: R/Layout.R

A format for formatting LogEvents as jsonlines log files. This provides a nice balance between human- an machine-readability.

Super class

lgr::Layout -> LayoutJson

Active bindings

toJSON_args

a list of values passed on to jsonlite::toJSON()

timestamp_fmt

Used by $format_event() to format timestamps.

Methods

Public methods

Inherited methods

    Method new()

    Usage

    LayoutJson$new(toJSON_args = list(auto_unbox = TRUE), timestamp_fmt = NULL)

    Method format_event()

    Usage

    LayoutJson$format_event(event)

    Method set_toJSON_args()

    Set arguments to pass on to jsonlite::toJSON()

    Usage

    LayoutJson$set_toJSON_args(x)

    Arguments

    x

    a named list

    Method set_timestamp_fmt()

    Set a format that this Layout will apply to timestamps.

    Usage

    LayoutJson$set_timestamp_fmt(x)

    Arguments

    x

    • NULL (the default): formatting of the timestamp is left to jsonlite::toJSON(),

    • a character scalar as for format.POSIXct(), or

    • a function that returns a vector of the same length as its (POSIXct) input. The returned vector can be of any type supported by jsonlite::toJSON(), but should usually be character.

    Method toString()

    Usage

    LayoutJson$toString()

    Method parse()

    Usage

    LayoutJson$parse(file)

    Method read()

    Usage

    LayoutJson$read(file, threshold = NA_integer_, n = 20L)

    Method clone()

    The objects of this class are cloneable with this method.

    Usage

    LayoutJson$clone(deep = FALSE)

    Arguments

    deep

    Whether to make a deep clone.

    Examples

    # setup a dummy LogEvent
event <- LogEvent$new(
  logger = Logger$new("dummy logger"),
  level = 200,
  timestamp = Sys.time(),
  caller = NA_character_,
  msg = "a test message",
  custom_field = "LayoutJson can handle arbitrary fields"
)

# Default settings show all event fals
lo <- LayoutJson$new()
lo$format_event(event)
#> {"level":200,"timestamp":"2023-03-04 20:04:30","logger":"dummy logger","caller":null,"msg":"a test message","custom_field":"LayoutJson can handle arbitrary fields"}