2.9 KiB
streamroller
node.js file streams that roll over when they reach a maximum size, or a date/time.
npm install streamroller
usage
var rollers = require('streamroller');
var stream = new rollers.RollingFileStream('myfile', 1024, 3);
stream.write("stuff");
stream.end();
The streams behave the same as standard node.js streams, except that when certain conditions are met they will rename the current file to a backup and start writing to a new file.
new RollingFileStream(filename [, maxSize, numBackups, options])
filename
(String)maxSize
- the size in bytes to trigger a rollover, if not provided this defaults to MAX_SAFE_INTEGER and the stream will not roll.numBackups
- the number of old files to keepoptions
- Objectencoding
- defaults to 'utf8'mode
- defaults to 0644flags
- defaults to 'a'compress
- (boolean) defaults tofalse
- compress the backup files using gzip (files will have.gz
extension).
This returns a WritableStream
. When the current file being written to (given by filename
) gets up to or larger than maxSize
, then the current file will be renamed to filename.1
and a new file will start being written to. Up to numBackups
of old files are maintained, so if numBackups
is 3 then there will be 4 files:
filename filename.1 filename.2 filename.3
When filename size >= maxSize then:
filename -> filename.1 filename.1 -> filename.2 filename.2 -> filename.3 filename.3 gets overwritten filename is a new file
new DateRollingFileStream(filename, pattern, options)
filename
(String)pattern
(String) - the date pattern to trigger rolling (see below)options
- Objectencoding
- defaults to 'utf8'mode
defaults to 0644flags
defaults to 'a'compress
- (boolean) compress the backup files, defaults to falsealwaysIncludePattern
- (boolean) extend the initial file with the pattern, defaults to false
This returns a WritableStream
. When the current time, formatted as pattern
, changes then the current file will be renamed to filename.formattedDate
where formattedDate
is the result of processing the date through the pattern, and a new file will begin to be written. Streamroller uses date-format to format dates, and the pattern
should use the date-format format. e.g. with a pattern
of "yyyy-MM-dd"
, and assuming today is August 29, 2013 then writing to the stream today will just write to filename
. At midnight, filename
will be renamed to filename.2013-08-29
and a new filename
will be created. If options.alwaysIncludePattern
is true, then the initial file will be filename.2013-08-29
and no renaming will occur at midnight, but a new file will be written to with the name filename.2013-08-30
.