Split logrus config out (#65)

- Keep main.go as simple as possiable

- Add `BYTOM_DEBUG` environment variable to set the log level to DEBUG

cmd/bytomd/log_hook.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	log "github.com/sirupsen/logrus"
+	"os"
+	"path"
+	"runtime"
+	"strings"
+)
+
+type ContextHook struct{}
+
+func (hook ContextHook) Levels() []log.Level {
+	return log.AllLevels
+}
+
+func (hook ContextHook) Fire(entry *log.Entry) error {
+	pc := make([]uintptr, 3, 3)
+	cnt := runtime.Callers(6, pc)
+
+	for i := 0; i < cnt; i++ {
+		fu := runtime.FuncForPC(pc[i] - 1)
+		name := fu.Name()
+		if !strings.Contains(name, "github.com/Sirupsen/log") {
+			file, line := fu.FileLine(pc[i] - 1)
+			entry.Data["file"] = path.Base(file)
+			entry.Data["func"] = path.Base(name)
+			entry.Data["line"] = line
+			break
+		}
+	}
+	return nil
+}
+
+func init() {
+	log.SetFormatter(&log.TextFormatter{FullTimestamp: true})
+
+	// If environment variable BYTOM_DEBUG is not empty,
+	// then add the hook to logrus and set the log level to DEBUG
+	if os.Getenv("BYTOM_DEBUG") != "" {
+		log.AddHook(ContextHook{})
+		log.SetLevel(log.DebugLevel)
+	}
+}

cmd/bytomd/main.go

@@ -2,44 +2,11 @@ package main
 
 import (
 	"github.com/bytom/cmd/bytomd/commands"
-	"github.com/sirupsen/logrus"
 	"github.com/tendermint/tmlibs/cli"
 	"os"
-	"path"
-	"runtime"
-	"strings"
 )
 
-type ContextHook struct{}
-
-func (hook ContextHook) Levels() []logrus.Level {
-	return logrus.AllLevels
-}
-
-func (hook ContextHook) Fire(entry *logrus.Entry) error {
-	pc := make([]uintptr, 3, 3)
-	cnt := runtime.Callers(6, pc)
-
-	for i := 0; i < cnt; i++ {
-		fu := runtime.FuncForPC(pc[i] - 1)
-		name := fu.Name()
-		if !strings.Contains(name, "github.com/Sirupsen/logrus") {
-			file, line := fu.FileLine(pc[i] - 1)
-			entry.Data["file"] = path.Base(file)
-			entry.Data["func"] = path.Base(name)
-			entry.Data["line"] = line
-			break
-		}
-	}
-	return nil
-}
-
-func init() {
-	logrus.SetFormatter(&logrus.TextFormatter{FullTimestamp: true})
-}
-
 func main() {
-	logrus.AddHook(ContextHook{})
 	cmd := cli.PrepareBaseCmd(commands.RootCmd, "TM", os.ExpandEnv("./.bytomd"))
 	cmd.Execute()
 }