A very simple logging library for node.js

npm install node-lumberjack
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A very simple logging library for node.js


  • Supports the %s format string - use it for every argument. If the parameter is not a string, it is converted to one using String(object)
  • Prints:
    • Timestamp
    • Log Statement Severity
    • Module Name
    • Constructor name
    • Function name
    • Line number

Example usage

var path     = require('path');
var filename = path.basename(path.normalize(__filename))
var log      = require('node-lumberjack').getLogger(filename, 'fatal');"Line 1");
log.warn("Line %s", 2);

See the file test.js for a complete example on how to use this library.

Example output

[2012-06-10 12:14:23.350] [INFO] [test.js:test:7] - Line 1
[2012-06-10 12:14:23.359] [WARN] [test.js:test:8] - Line 2
[2012-06-10 12:14:23.359] [DEBUG] [test.js:test:9] - 3rd line
[2012-06-10 12:14:23.360] [ERROR] [test.js:test:10] - 4th Line comes here
[2012-06-10 12:14:23.360] [TRACE] [test.js:test:11] - Tracing on the 5th line

node-lumberjack prints the module name, constructor name, function name and the line number on which the logging function was called. Here is an example:

[2012-06-10 12:14:23.362] [TRACE] [test.js:CtorName.functionName:20] - You should see the object & function name on this line
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