chore(logging)_: introduce geth adapter

logutils/geth_adapter.go

@@ -0,0 +1,51 @@
+package logutils
+
+import (
+	"fmt"
+	"strings"
+
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+
+	"github.com/ethereum/go-ethereum/log"
+)
+
+// gethAdapter returns a log.Handler interface that forwards logs to a zap.Logger.
+// Logs are forwarded raw as if geth were printing them.
+func gethAdapter(logger *zap.Logger) log.Handler {
+	return log.FuncHandler(func(r *log.Record) error {
+		level, err := lvlFromString(r.Lvl.String())
+		if err != nil {
+			return err
+		}
+		// Skip trace logs to not clutter the output
+		if level == traceLevel {
+			return nil
+		}
+		serializedLog := string(log.TerminalFormat(false).Format(r))
+		logger.Check(level, fmt.Sprintf("'%s'", strings.TrimSuffix(serializedLog, "\n"))).Write()
+		return nil
+	})
+}
+
+const traceLevel = zapcore.DebugLevel - 1
+
+// lvlFromString returns the appropriate zapcore.Level from a string.
+func lvlFromString(lvlString string) (zapcore.Level, error) {
+	switch strings.ToLower(lvlString) {
+	case "trace", "trce":
+		return traceLevel, nil // zap does not have a trace level, use custom
+	case "debug", "dbug":
+		return zapcore.DebugLevel, nil
+	case "info":
+		return zapcore.InfoLevel, nil
+	case "warn":
+		return zapcore.WarnLevel, nil
+	case "error", "eror":
+		return zapcore.ErrorLevel, nil
+	case "crit":
+		return zapcore.DPanicLevel, nil // zap does not have a crit level, using DPanicLevel as closest
+	default:
+		return zapcore.InvalidLevel, fmt.Errorf("unknown level: %v", lvlString)
+	}
+}

logutils/geth_adapter_test.go

@@ -0,0 +1,43 @@
+package logutils
+
+import (
+	"bytes"
+	"testing"
+
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/ethereum/go-ethereum/log"
+)
+
+func TestGethAdapter(t *testing.T) {
+	level := zap.NewAtomicLevelAt(zap.InfoLevel)
+	buffer := bytes.NewBuffer(nil)
+
+	core := zapcore.NewCore(
+		zapcore.NewConsoleEncoder(zap.NewDevelopmentEncoderConfig()),
+		zapcore.AddSync(buffer),
+		level,
+	)
+	logger := zap.New(core)
+
+	log.Root().SetHandler(gethAdapter(logger))
+
+	log.Debug("should not be printed, as it's below the log level")
+	require.Empty(t, buffer.String())
+
+	buffer.Reset()
+	log.Info("should be printed")
+	require.Regexp(t, `INFO\s+'INFO\s*\[.*\]\s*should be printed '`, buffer.String())
+
+	buffer.Reset()
+	level.SetLevel(zap.DebugLevel)
+	log.Debug("should be printed with context", "value1", 12345, "value2", "string")
+	require.Regexp(t, `DEBUG\s+'DEBUG\s*\[.*\]\s*should be printed with context\s+value1=12345\s+value2=string'`, buffer.String())
+
+	buffer.Reset()
+	log.Trace("should be skipped")
+	require.Empty(t, buffer.String())
+}