cmd.go

// +build go1.2

// Copyright 2013 com 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 com is an open source project for commonly used functions for the Go programming language.
package com

import (
	"bytes"
	"fmt"
	"os/exec"
	"runtime"
	"strings"
)

// ExecCmdDirBytes executes system command in given directory
// and return stdout, stderr in bytes type, along with possible error.
func ExecCmdDirBytes(dir, cmdName string, args ...string) ([]byte, []byte, error) {
	bufOut := new(bytes.Buffer)
	bufErr := new(bytes.Buffer)

	cmd := exec.Command(cmdName, args...)
	cmd.Dir = dir
	cmd.Stdout = bufOut
	cmd.Stderr = bufErr

	err := cmd.Run()
	return bufOut.Bytes(), bufErr.Bytes(), err
}

// ExecCmdBytes executes system command
// and return stdout, stderr in bytes type, along with possible error.
func ExecCmdBytes(cmdName string, args ...string) ([]byte, []byte, error) {
	return ExecCmdDirBytes("", cmdName, args...)
}

// ExecCmdDir executes system command in given directory
// and return stdout, stderr in string type, along with possible error.
func ExecCmdDir(dir, cmdName string, args ...string) (string, string, error) {
	bufOut, bufErr, err := ExecCmdDirBytes(dir, cmdName, args...)
	return string(bufOut), string(bufErr), err
}

// ExecCmd executes system command
// and return stdout, stderr in string type, along with possible error.
func ExecCmd(cmdName string, args ...string) (string, string, error) {
	return ExecCmdDir("", cmdName, args...)
}

// _________        .__                 .____
// \_   ___ \  ____ |  |   ___________  |    |    ____   ____
// /    \  \/ /  _ \|  |  /  _ \_  __ \ |    |   /  _ \ / ___\
// \     \___(  <_> )  |_(  <_> )  | \/ |    |__(  <_> ) /_/  >
//  \______  /\____/|____/\____/|__|    |_______ \____/\___  /
//         \/                                   \/    /_____/

// Color number constants.
const (
	Gray = uint8(iota + 90)
	Red
	Green
	Yellow
	Blue
	Magenta
	//NRed      = uint8(31) // Normal
	EndColor = "\033[0m"
)

// getColorLevel returns colored level string by given level.
func getColorLevel(level string) string {
	level = strings.ToUpper(level)
	switch level {
	case "TRAC":
		return fmt.Sprintf("\033[%dm%s\033[0m", Blue, level)
	case "ERRO":
		return fmt.Sprintf("\033[%dm%s\033[0m", Red, level)
	case "WARN":
		return fmt.Sprintf("\033[%dm%s\033[0m", Magenta, level)
	case "SUCC":
		return fmt.Sprintf("\033[%dm%s\033[0m", Green, level)
	default:
		return level
	}
}

// ColorLogS colors log and return colored content.
// Log format: <level> <content [highlight][path]> [ error ].
// Level: TRAC -> blue; ERRO -> red; WARN -> Magenta; SUCC -> green; others -> default.
// Content: default; path: yellow; error -> red.
// Level has to be surrounded by "[" and "]".
// Highlights have to be surrounded by "# " and " #"(space), "#" will be deleted.
// Paths have to be surrounded by "( " and " )"(space).
// Errors have to be surrounded by "[ " and " ]"(space).
// Note: it hasn't support windows yet, contribute is welcome.
func ColorLogS(format string, a ...interface{}) string {
	log := fmt.Sprintf(format, a...)

	var clog string

	if runtime.GOOS != "windows" {
		// Level.
		i := strings.Index(log, "]")
		if log[0] == '[' && i > -1 {
			clog += "[" + getColorLevel(log[1:i]) + "]"
		}

		log = log[i+1:]

		// Error.
		log = strings.Replace(log, "[ ", fmt.Sprintf("[\033[%dm", Red), -1)
		log = strings.Replace(log, " ]", EndColor+"]", -1)

		// Path.
		log = strings.Replace(log, "( ", fmt.Sprintf("(\033[%dm", Yellow), -1)
		log = strings.Replace(log, " )", EndColor+")", -1)

		// Highlights.
		log = strings.Replace(log, "# ", fmt.Sprintf("\033[%dm", Gray), -1)
		log = strings.Replace(log, " #", EndColor, -1)

	} else {
		// Level.
		i := strings.Index(log, "]")
		if log[0] == '[' && i > -1 {
			clog += "[" + log[1:i] + "]"
		}

		log = log[i+1:]

		// Error.
		log = strings.Replace(log, "[ ", "[", -1)
		log = strings.Replace(log, " ]", "]", -1)

		// Path.
		log = strings.Replace(log, "( ", "(", -1)
		log = strings.Replace(log, " )", ")", -1)

		// Highlights.
		log = strings.Replace(log, "# ", "", -1)
		log = strings.Replace(log, " #", "", -1)
	}
	return clog + log
}

// ColorLog prints colored log to stdout.
// See color rules in function 'ColorLogS'.
func ColorLog(format string, a ...interface{}) {
	fmt.Print(ColorLogS(format, a...))
}