Logrus is a popular structured logger that allows to add hooks that are invoked for every message. These hooks can be used to send the messages to remote tracking and reporting system. Things may go wrong when talking to remote systems, like delays and errors.
The hooks from this package are decorators that help to deal with:
- Transient errors
- Excessive logging messages
- Slow transmission times
The examples will use the syslog hook to send messages to syslog daemon. The setup looks like this:
import (
"log/syslog"
"github.com/misho-kr/logrus-hooks"
"github.com/sirupsen/logrus"
lSyslog "github.com/sirupsen/logrus/hooks/syslog"
)
func init() {
// create a hook to be added to an instance of logger
hook, err := NewSyslogHook("udp", "server.fqdn:514", syslog.LOG_DEBUG, "")
}From here additional hooks can be added for enhanced logging functionality.
Prevent transient errors from procesing the log messages with retries
log.AddHook(RetryHook(
hook,
100 * time.Millisecond, // delay between retries
hooks.Retries(3), // retry 3 times
hooks.FactorPct(100), // increase delay by 100% between retries
hooks.JitterPct(10), // jitter of 10% to the delay between retries
))Put a cap on the number of logging messages per time interval
log.AddHook(RateLimitHook(
hook,
hooks.PerSecond(10), // 10 messages per second
hooks.Burst(20), // burst of 20 messages allowed
))Fire the hook in separate goroutine to avoid blocking the logger and main application
log.AddHook(AsyncHook(
hook,
hooks.Senders(10), // 10 goroutines to send messages
hooks.BoostSenders(20), // up to 20 additional goroutines when needed
))