lua-simplelog: Overview

lua-simplelog is a logging library that aims to be performant, simple, and capable. It exposes a log mannager which in turn is used to open up log files in the log directory. The loggers keep up with dates and roll to a new file when the date changes. It provides for multiple levels out of the box. Each log can use either the default write settings, or their own. Write settings allow for telling the logger which level's are enabled for which output.

Future

Perhaps allow dynamically adding levels and/or writers?
Perhaps allow for name formats for log files?
Perhaps allow for each log file to have its own folder?

Usage

local log_config = {
  -- this directory must exist!
  -- must end in a '/'
  dir = '/tmp/simplelog/',
  daemonized = true,
  debug_info = true,
  logs = {
    default = {
      levels = {
        write = 'info',
        print = 'info'
      }
    },
    log1 = {
      levels = {
        write = 'info',
        print = 'trace'
      }
    }
  }
}

local log_manager = require 'simplelog' (log_config)
local uses_default = log_manager:open 'loga'
local log1 = log_manager:open 'log1'
-- should not print or write to file
uses_default:trace 'This is a message'
-- should print and write to file
uses_default:error('Error %s', 1000)
-- should print but not write to file
log1:trace 'This is a message'
-- should print and write to file
log1:error 'This is a message too'
log_manager:close_all()

Documentation

Levels

These are the available log levels in order of importance with highest importance being listed last.

trace
debug
info
warn
error
fatal

Log manager

This is what's returned when you import the module.

Once you initialize a manager with a config like local manager = require 'simplelog' (cfg_table) the following functions become avaliable:

Functions: * open(string name) - opens a log file with the name given and creates said file under the directory given in the configuration. Returns the log file object. * close(string name) - closes a previously opened log file by name * closeall() - closes all log files managed by this manager

Configuration is explained below:

Excerpt from example:

  dir = '/tmp/simplelog/',
  daemonized = true,
  debug_info = true,
  logs = {
    default = {
      levels = {
        write = 'info',
        print = 'info'
      }
    },
    log1 = {
      levels = {
        write = 'info',
        print = 'trace'
      }
    }
  }
}

The table key dir is required and is the directory in which log files will be created. The logs.default is also required. The rest is optional.

Manager configuration:

dir : The directory to which log files will be written.
daemonized : Used to determine if it is neccessary to disable stdout/stderr logging.
debug_info: If enabled, the logger will include source line info in the output.

Log Configuration:

Each log can be configured to only write log lines above a certain level. If a log, specified by name in the config, exists, then that configuration is used for determining when to write information, otherwise the default. Currently logs only support writing to files (write), or writing to the screen (print). Each log config is found under the configuration table at config.logs and config.logs.default must exist. Each log's configuration follows the same format as config.logs.default. Each log config has a levels table and must have 2 keys present (one for each currently supported write situation). These keys simply must be set to one of the log levels defined above and only levels equal or greater in importance in relation to that log will be logged. Look to the excerpt for a demonstration. The levels per output can be different.

Log Object