✨ New feature: Compressing rotated log files

One requested feature for logga was to compress rotated log files to save disk space. Well, we have good news: version 1.1.1 brings you log compression!

To start to use the feature, add the compressArchives: true to the config.yaml configuration file, or update your MDM Configuration Profile.

How log compression works?

Log rotation is controlled by the maxLogFileCount and maxLogFileSize configuration keys.
maxLogFileCount tells logga how many rotated log files to keep at once. maxLogFileSize signals logga when to rotate the current log file: when the file size surpasses the configured bytes, the file gets rotated.

Initially, logs get written into audit.log (or access.log) file. A rotation event is shown in the following timeline:

# maxLogFileCount: 2

1.
[logging] logga -> audit.log

2. maxLogFileSize reached
[rotation] audit.log -> audit.log.1
[logging] logga -> audit.log

3. maxLogFileSize reached again
[rotation] audit.log.1 -> audit.log.2
[rotation] audit.log -> audit.log.1
[logging] logga -> audit.log

4. maxLogFileSize reached again
[delete] audit.log.2
[rotation] audit.log.1 -> audit.log.2
[rotation] audit.log -> audit.log.1
[logging] logga -> audit.log
...

When log compression is turned on (compressArchives: true), the rotation rules still take effect, but the files will be a bit different.

# maxLogFileCount: 2

1.
[logging] logga -> audit.log

2. maxLogFileSize reached
[rotation] audit.log -> audit.log.1 
|-> [compression] audit.log.1 -> audit.log.1710807884.gzip
[logging] logga -> audit.log

3. maxLogFileSize reached again
[no action] audit.log.1710807884.gzip
[rotation] audit.log -> audit.log.1 
|-> [compression] audit.log.1 -> audit.log.1710808030.gzip
[logging] logga -> audit.log

4. maxLogFileSize reached again
[delete] audit.log.1710807884.gzip
[no action] audit.log.1710808030.gzip
[rotation] audit.log -> audit.log.1 
|-> [compression] audit.log.1 -> audit.log.1710808102.gzip
[logging] logga -> audit.log

...

If log compression is turned on, it makes sense to bump maxLogFileCount to a high number, like 50-100, so compressed files are kept and not frequently rotated.

We hope this feature will be a useful addition to your audit-logging toolchain! If you need help with setting up logga, contact support or open an issue on Github.