whisk/trace.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.
 */

package whisk

import (
	"fmt"
	"os"
	"runtime"
	"strings"
)

type DebugLevel string

const (
	DbgInfo  DebugLevel = "Inf"
	DbgWarn  DebugLevel = "Wrn"
	DbgError DebugLevel = "Err"
	DbgFatal DebugLevel = "Ftl"
)

const MaxNameLen int = 25

var isVerbose bool
var isDebug bool

func init() {
	if len(os.Getenv("WSK_CLI_DEBUG")) > 0 { // Useful for tracing init() code, before parms are parsed
		SetDebug(true)
	}
}

func SetDebug(b bool) {
	isDebug = b
}

func SetVerbose(b bool) {
	isVerbose = b
}

func IsVerbose() bool {
	return isVerbose || isDebug
}
func IsDebug() bool {
	return isDebug
}

/* Function for tracing debug level messages to stdout
   Output format:
   [file-or-function-name]:line-#:[DebugLevel] The formatted message without any appended \n
*/
func Debug(dl DebugLevel, msgFormat string, args ...interface{}) {
	if isDebug {
		pc, file, line, _ := runtime.Caller(1)
		fcn := runtime.FuncForPC(pc)
		msg := fmt.Sprintf(msgFormat, args...)
		fcnName := fcn.Name()

		// Cobra command Run/RunE functions are anonymous, so the function name is unfriendly;
		// use the file name instead
		if strings.Contains(fcnName, "commands.glob.") || strings.Contains(fcnName, "whisk.glob.") {
			fcnName = file
		}

		// Only interested in the the trailing function/file name characters
		if len(fcnName) > MaxNameLen {
			fcnName = fcnName[len(fcnName)-MaxNameLen:]
		}
		fmt.Printf("[%-25s]:%03d:[%3s] %v", fcnName, line, dl, msg)
	}
}

/* Function for tracing debug level messages to stdout
   Output format:
   [file-or-function-name]:line-#:[DebugLevel] The formatted message without any appended newline characters
*/
func Verbose(msgFormat string, args ...interface{}) {
	if IsVerbose() {
		msg := fmt.Sprintf(msgFormat, args...)
		fmt.Printf("%v", msg)
	}
}