use logrus for logging

main.go

@@ -3,11 +3,21 @@ package main
 import (
 	"github.com/vulcanize/vulcanizedb/cmd"
 
+	log "github.com/sirupsen/logrus"
 	"github.com/spf13/viper"
 	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
+	"os"
 )
 
 func main() {
+	log.SetFormatter(&log.JSONFormatter{})
+	file, err := os.OpenFile("vulcanizedb.log", os.O_CREATE|os.O_WRONLY, 0666)
+	if err == nil {
+		log.SetOutput(file)
+	} else {
+		log.Info("Failed to log to file, using default stderr")
+	}
+
 	tracer.Start(tracer.WithServiceName(viper.GetString("datadog.name")))
 
 	cmd.Execute()