ldoc

• Index

Contents

• Provided features
• Example
• Custom Formatters:

Topics

• readme

Modules

• lumber.format.file
• lumber.format.plain
• lumber.format.term
• lumber

Lumber

A simple and extensible logging library for Lua

Provided features

• Log Levels
• Default formatters (Term, File and Plain)
• Function arguments (for expensive debugging info)
• Simple extension interface

Example

local lumber = require 'lumber'

log = lumber.new {
    format = require 'lumber.format.term'; -- default is lumber.format.plain
 out = io.stderr; -- default
 level = lumber.levels.DEBUG; -- default is INFO
 separator = "\n"; -- default is single space
 filter = require 'inspect'; -- default tostring
}

log("Some Information") -- same as log:info()

log("Foo", "Bar") -- Concatenated with separator

log(some_object) -- Fed through filter before printing

log:debug(
    "Open connections:",
    list_open_connections -- Won't get called when log level < debug
)

Custom Formatters:

Formatters are functions that take the log level (as an object) and a single input string. Function calling and argument concatenation is taken care of by the library. They are expected to output a single string to be written to the output object.

-- Custom formatter to prepend the log level name
local my_formatter(level, input)
    return level.name .. " : " .. input
end