Add MustNewPrometheusHook for less verbose hook initialisation (+tests).

promrus.go

@@ -13,6 +13,8 @@ type PrometheusHook struct {
 var supportedLevels = []logrus.Level{logrus.DebugLevel, logrus.InfoLevel, logrus.WarnLevel, logrus.ErrorLevel}
 
 // NewPrometheusHook creates a new instance of PrometheusHook which exposes Prometheus counters for various log levels.
+// Contrarily to MustNewPrometheusHook, it returns an error to the caller in case of issue.
+// Use NewPrometheusHook if you want more control. Use MustNewPrometheusHook if you want a less verbose hook creation.
 func NewPrometheusHook() (*PrometheusHook, error) {
 	counterVec := prometheus.NewCounterVec(prometheus.CounterOpts{
 		Name: "log_messages",
@@ -32,6 +34,17 @@ func NewPrometheusHook() (*PrometheusHook, error) {
 	}, nil
 }
 
+// MustNewPrometheusHook creates a new instance of PrometheusHook which exposes Prometheus counters for various log levels.
+// Contrarily to NewPrometheusHook, it does not return any error to the caller, but panics instead.
+// Use MustNewPrometheusHook if you want a less verbose hook creation. Use NewPrometheusHook if you want more control.
+func MustNewPrometheusHook() *PrometheusHook {
+	hook, err := NewPrometheusHook()
+	if err != nil {
+		panic(err)
+	}
+	return hook
+}
+
 // Fire increments the appropriate Prometheus counter depending on the entry's log level.
 func (hook *PrometheusHook) Fire(entry *logrus.Entry) error {
 	hook.counterVec.WithLabelValues(entry.Level.String()).Inc()

promrus_test.go

@@ -23,8 +23,7 @@ const (
 
 func TestExposeAndQueryLogrusCounters(t *testing.T) {
 	// Create Prometheus hook and configure logrus to use it:
-	hook, err := promrus.NewPrometheusHook()
-	assert.Nil(t, err)
+	hook := promrus.MustNewPrometheusHook()
 	log.AddHook(hook)
 	log.SetLevel(log.DebugLevel)