diff --git a/vendor/github.com/coreos/etcd/pkg/logutil/zap.go b/vendor/github.com/coreos/etcd/pkg/logutil/zap.go
new file mode 100644
index 0000000..2f69223
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/pkg/logutil/zap.go
@@ -0,0 +1,97 @@
+// Copyright 2019 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package logutil
+
+import (
+	"sort"
+
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+)
+
+// DefaultZapLoggerConfig defines default zap logger configuration.
+var DefaultZapLoggerConfig = zap.Config{
+	Level: zap.NewAtomicLevelAt(ConvertToZapLevel(DefaultLogLevel)),
+
+	Development: false,
+	Sampling: &zap.SamplingConfig{
+		Initial:    100,
+		Thereafter: 100,
+	},
+
+	Encoding: "json",
+
+	// copied from "zap.NewProductionEncoderConfig" with some updates
+	EncoderConfig: zapcore.EncoderConfig{
+		TimeKey:        "ts",
+		LevelKey:       "level",
+		NameKey:        "logger",
+		CallerKey:      "caller",
+		MessageKey:     "msg",
+		StacktraceKey:  "stacktrace",
+		LineEnding:     zapcore.DefaultLineEnding,
+		EncodeLevel:    zapcore.LowercaseLevelEncoder,
+		EncodeTime:     zapcore.ISO8601TimeEncoder,
+		EncodeDuration: zapcore.StringDurationEncoder,
+		EncodeCaller:   zapcore.ShortCallerEncoder,
+	},
+
+	// Use "/dev/null" to discard all
+	OutputPaths:      []string{"stderr"},
+	ErrorOutputPaths: []string{"stderr"},
+}
+
+// AddOutputPaths adds output paths to the existing output paths, resolving conflicts.
+func AddOutputPaths(cfg zap.Config, outputPaths, errorOutputPaths []string) zap.Config {
+	outputs := make(map[string]struct{})
+	for _, v := range cfg.OutputPaths {
+		outputs[v] = struct{}{}
+	}
+	for _, v := range outputPaths {
+		outputs[v] = struct{}{}
+	}
+	outputSlice := make([]string, 0)
+	if _, ok := outputs["/dev/null"]; ok {
+		// "/dev/null" to discard all
+		outputSlice = []string{"/dev/null"}
+	} else {
+		for k := range outputs {
+			outputSlice = append(outputSlice, k)
+		}
+	}
+	cfg.OutputPaths = outputSlice
+	sort.Strings(cfg.OutputPaths)
+
+	errOutputs := make(map[string]struct{})
+	for _, v := range cfg.ErrorOutputPaths {
+		errOutputs[v] = struct{}{}
+	}
+	for _, v := range errorOutputPaths {
+		errOutputs[v] = struct{}{}
+	}
+	errOutputSlice := make([]string, 0)
+	if _, ok := errOutputs["/dev/null"]; ok {
+		// "/dev/null" to discard all
+		errOutputSlice = []string{"/dev/null"}
+	} else {
+		for k := range errOutputs {
+			errOutputSlice = append(errOutputSlice, k)
+		}
+	}
+	cfg.ErrorOutputPaths = errOutputSlice
+	sort.Strings(cfg.ErrorOutputPaths)
+
+	return cfg
+}