log-rotate-stream

Stream data to a rotating log file. When the output.log file grows too big, it is moved to output.log.0. By default, 10 old log files are saved, and they are always numbered in order of age. So output.log.0 is always the most recent archive, and output.log.9 the oldest archive.

For example, log the output of a child process:

var fork = require('child_process').fork,
  es = require('event-stream'),
  createLogStream = require('log-rotate-stream');
 
var child = fork('child.js', {silent: true});
 
es.merge(child.stdout, child.stderr).pipe(createLogStream('child.log'));

createLogStream(path, options)

Create and return a new log stream to path. The optional arguments are:

• maxSize - When the log file exceeds this size, it will be rotated. Default: 5 * 1024 * 1024 (5 MB)

• count - The number of old log files to save. Default: 10.

Note that the log is rotated when maxSize is exceeded. This is so that typically only complete messages will be written to the log.