This project is not maintained anymore. I recommend you using https://github.com/influxdata/go-syslog/blob/develop/rfc5424/builder.go instead, which has all the features this library provided plus tons of others. It is also maintained by the InfluxDB engineering team, which ensures continuity on development.
A syslog formatter Golang library.
This library formats syslog messages according the RFC5424 and RFC3164.
$ go get github.com/smoya/syslog-format