LuaLogging: A simple API to use logging features in Lua

Console appender

Console is the simplest appender. It just writes the log messages to io.stdout or io.stderr.

function logging.console {
    [destination = "stdout"|"stderr",]

    [logPattern = string,]
    [logPatterns = {
      [logging.DEBUG = string,]
      [logging.INFO  = string,]
      [logging.WARN  = string,]
      [logging.ERROR = string,]
      [logging.FATAL = string,]
    },]
    [timestampPattern = string,]
    [logLevel = log-level-constant,]
}

logPatterns:
A table with logPattern strings indexed by the log-levels. A logPattern specifies how the message is written.
If this parameter is omitted, a patterns table will be created with the parameter logPattern as the default value for each log-level. If logPattern also is omitted then each level will fall back to the current default setting, see logging.defaultLogPatterns.
logPattern:
This value will be used as the default value for each log-level that was omitted in logPatterns.
timestampPattern:
This is an optional parameter that can be used to specify a date/time formatting in the log message. See logging.date for the format. The default is taken from logging.defaultTimestampPattern().
destination:
The destination stream, optional. The value can be either "stdout", or "stderr". The default is stdout.
logLevel:
The initial log-level to set for the created logger.

Examples

local ansicolors = require("ansicolors") -- https://github.com/kikito/ansicolors.lua
local ll = require("logging")
require "logging.console"

-- set up the default logger to stderr + colorization
ll.defaultLogger(ll.console {
  logLevel = ll.DEBUG,
  destination = "stderr",
  timestampPattern = "%y-%m-%d %H:%M:%S",
  logPatterns = {
    [ll.DEBUG] = ansicolors("%date%{cyan} %level %message %{reset}(%source)\n"),
    [ll.INFO] = ansicolors("%date %level %message\n"),
    [ll.WARN] = ansicolors("%date%{yellow} %level %message\n"),
    [ll.ERROR] = ansicolors("%date%{red bright} %level %message %{reset}(%source)\n"),
    [ll.FATAL] = ansicolors("%date%{magenta bright} %level %message %{reset}(%source)\n"),
  }
})

local log = ll.defaultLogger()

log:info("logging.console test")
log:debug("debugging...")
log:error("error!")