minio/main.go

/*
 * Minio Cloud Storage, (C) 2015 Minio, Inc.
 *
 * 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 main

import (
	"fmt"
	"os"
	"runtime"
	"sort"
	"strconv"

	"github.com/dustin/go-humanize"
	"github.com/minio/cli"
	"github.com/minio/minio/pkg/probe"
)

// Help template for minio.
var minioHelpTemplate = `NAME:
  {{.Name}} - {{.Usage}}

DESCRIPTION:
  {{.Description}}

USAGE:
  minio {{if .Flags}}[flags] {{end}}command{{if .Flags}}{{end}} [arguments...]

COMMANDS:
  {{range .Commands}}{{join .Names ", "}}{{ "\t" }}{{.Usage}}
  {{end}}{{if .Flags}}
FLAGS:
  {{range .Flags}}{{.}}
  {{end}}{{end}}
VERSION:
  ` + minioVersion +
	`{{ "\n"}}{{range $key, $value := ExtraInfo}}
{{$key}}:
  {{$value}}
{{end}}`

// init - check the environment before main starts
func init() {
	// Check if minio was compiled using a supported version of Golang.
	checkGoVersion()

	// It is an unsafe practice to run network services as
	// root. Containers are an exception.
	if !isContainerized() && os.Geteuid() == 0 {
		Fatalln("Please run ‘minio’ as a non-root user.")
	}

}

func migrate() {
	// Migrate config file
	migrateConfig()
}

// Tries to get os/arch/platform specific information
// Returns a map of current os/arch/platform/memstats
func getSystemData() map[string]string {
	host, err := os.Hostname()
	if err != nil {
		host = ""
	}
	memstats := &runtime.MemStats{}
	runtime.ReadMemStats(memstats)
	mem := fmt.Sprintf("Used: %s | Allocated: %s | Used-Heap: %s | Allocated-Heap: %s",
		humanize.Bytes(memstats.Alloc),
		humanize.Bytes(memstats.TotalAlloc),
		humanize.Bytes(memstats.HeapAlloc),
		humanize.Bytes(memstats.HeapSys))
	platform := fmt.Sprintf("Host: %s | OS: %s | Arch: %s",
		host,
		runtime.GOOS,
		runtime.GOARCH)
	goruntime := fmt.Sprintf("Version: %s | CPUs: %s", runtime.Version(), strconv.Itoa(runtime.NumCPU()))
	return map[string]string{
		"PLATFORM": platform,
		"RUNTIME":  goruntime,
		"MEM":      mem,
	}
}

func findClosestCommands(command string) []string {
	var closestCommands []string
	for _, value := range commandsTree.PrefixMatch(command) {
		closestCommands = append(closestCommands, value.(string))
	}
	sort.Strings(closestCommands)
	// Suggest other close commands - allow missed, wrongly added and
	// even transposed characters
	for _, value := range commandsTree.walk(commandsTree.root) {
		if sort.SearchStrings(closestCommands, value.(string)) < len(closestCommands) {
			continue
		}
		// 2 is arbitrary and represents the max
		// allowed number of typed errors
		if DamerauLevenshteinDistance(command, value.(string)) < 2 {
			closestCommands = append(closestCommands, value.(string))
		}
	}
	return closestCommands
}

func registerApp() *cli.App {
	// register all commands
	registerCommand(serverCmd)
	registerCommand(configCmd)
	registerCommand(versionCmd)
	registerCommand(updateCmd)

	// register all flags
	registerFlag(configFolderFlag)
	registerFlag(addressFlag)
	registerFlag(accessLogFlag)
	registerFlag(certFlag)
	registerFlag(keyFlag)

	// set up app
	app := cli.NewApp()
	app.Name = "Minio"
	app.Author = "Minio.io"
	app.Usage = "Cloud Storage Server for Micro Services."
	app.Description = `Micro services environment provisions one Minio server per application instance. Scalability is achieved through large number of smaller personalized instances. This version of the Minio binary is built using Filesystem storage backend for magnetic and solid state disks.`
	app.Flags = flags
	app.Commands = commands
	app.CustomAppHelpTemplate = minioHelpTemplate
	app.CommandNotFound = func(ctx *cli.Context, command string) {
		msg := fmt.Sprintf("‘%s’ is not a minio sub-command. See ‘minio help’.", command)
		closestCommands := findClosestCommands(command)
		if len(closestCommands) > 0 {
			msg += fmt.Sprintf("\n\nDid you mean one of these?\n")
			for _, cmd := range closestCommands {
				msg += fmt.Sprintf("        ‘%s’\n", cmd)
			}
		}
		Fatalln(msg)
	}
	return app
}

func checkMainSyntax(c *cli.Context) {
	configPath, err := getConfigPath()
	if err != nil {
		Fatalf("Unable to obtain user's home directory. \nError: %s\n", err)
	}
	if configPath == "" {
		Fatalf("Config folder cannot be empty, please specify --config-folder <foldername>.")
	}
}

func main() {
	probe.Init() // Set project's root source path.
	probe.SetAppInfo("Release-Tag", minioReleaseTag)
	probe.SetAppInfo("Commit-ID", minioShortCommitID)

	app := registerApp()
	app.Before = func(c *cli.Context) error {
		// Sets new config folder.
		setGlobalConfigPath(c.GlobalString("config-folder"))

		// Valid input arguments to main.
		checkMainSyntax(c)

		// Migrate any old version of config / state files to newer format.
		migrate()

		return nil
	}
	app.ExtraInfo = func() map[string]string {
		return getSystemData()
	}

	app.RunAndExitOnError()
}