Factory-Pattern log module with rotatable DefaultWriter (file) in Golang.
<Logger>
<!-- Directory in which log files will be placed. -->
<Directory>logs/</Directory>
<!-- Log file name, which will be formated with datetime. -->
<FileName>2006-01-02 15-04-05.000.log</FileName>
<!-- Level could be one of "trace", "debug[N]", "info", "warn", "error". -->
<!-- N could be 0-7, and "debug0" equals to "debug". -->
<Level>trace|debug1|info|warn|error</Level>
<Rotation>
<!-- Maximum file size in kilobytes (1024 bytes). -->
<MaxSize>32768</MaxSize>
<!-- Rotation Time, there are 2 types: -->
<!-- If type="daily", rotation only occurs every 24 hours, and the format -->
<!-- is hh:mm:ss, for example 00:00:00 will rotates every midnight; -->
<!-- If type="duration", rotation occurs when the duration of the log -->
<!-- exceed a certain length. A duration string is a possibly signed -->
<!-- sequence of decimal numbers, each with optional fraction and a unit -->
<!-- suffix, such as "300ms", "1.5h" or "2h45m". Valid time units are -->
<!-- "ns", "us" (or "µs"), "ms", "s", "m", "h". -->
<Schedule type="daily">00:00:00</Schedule>
<!-- Max number of log files to keep. -->
<History>32</History>
</Rotation>
</Logger>constraints := new(log.DefaultWriterConstraints)
constraints.Directory = "logs/"
constraints.FileName = "2006-01-02 15-04-05.000.log"
constraints.Level = "trace|debug1|info|warn|error"
constraints.Rotation.MaxSize = 32 * 1024 * 1024
constraints.Rotation.Schedule.Type = "daily"
constraints.Rotation.Schedule.Duration = "00:00:00"
constraints.Rotation.History = 32
factory := log.NewDefaultLoggerFactory(constraints)
logger := factory.NewLogger("CORE")
logger.Infof("Hello, %s", "world")
logger.Debugf(1, "Hello, %s", "world")