xds/utils/grpclog/prefixLogger.go

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */

/*
 *
 * Copyright 2020 gRPC authors.
 *
 */

package grpclog

import (
	"fmt"
)

// PrefixLogger does logging with a prefix.
//
// Logging method on a nil logs without any prefix.
type PrefixLogger struct {
	logger DepthLoggerV2
	prefix string
}

// Infof does info logging.
func (pl *PrefixLogger) Infof(format string, args ...interface{}) {
	if pl != nil {
		// Handle nil, so the tests can pass in a nil logger.
		format = pl.prefix + format
		pl.logger.InfoDepth(1, fmt.Sprintf(format, args...))
		return
	}
	InfoDepth(1, fmt.Sprintf(format, args...))
}

// Warnf does warning logging.
func (pl *PrefixLogger) Warnf(format string, args ...interface{}) {
	if pl != nil {
		format = pl.prefix + format
		pl.logger.WarningDepth(1, fmt.Sprintf(format, args...))
		return
	}
	WarningDepth(1, fmt.Sprintf(format, args...))
}

// Errorf does error logging.
func (pl *PrefixLogger) Errorf(format string, args ...interface{}) {
	if pl != nil {
		format = pl.prefix + format
		pl.logger.ErrorDepth(1, fmt.Sprintf(format, args...))
		return
	}
	ErrorDepth(1, fmt.Sprintf(format, args...))
}

// NewPrefixLogger creates a prefix logger with the given prefix.
func NewPrefixLogger(logger DepthLoggerV2, prefix string) *PrefixLogger {
	return &PrefixLogger{logger: logger, prefix: prefix}
}