gen-ldflags.go

// +build ignore

/*
 * Federator, (C) 2017 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"
	"os/exec"
	"strings"
	"time"
)

func genLDFlags(version string) string {
	ldflagsStr := "-s -w"
	ldflagsStr += " -X github.com/minio/federator/cmd.Version=" + version
	ldflagsStr += " -X github.com/minio/federator/cmd.ReleaseTag=" + releaseTag(version)
	ldflagsStr += " -X github.com/minio/federator/cmd.CommitID=" + commitID()
	ldflagsStr += " -X github.com/minio/federator/cmd.ShortCommitID=" + commitID()[:12]
	ldflagsStr += " -X github.com/minio/federator/cmd.GOPATH=" + os.Getenv("GOPATH")
	return ldflagsStr
}

// genReleaseTag prints release tag to the console for easy git tagging.
func releaseTag(version string) string {
	relPrefix := "DEVELOPMENT"
	if prefix := os.Getenv("FEDERATOR_RELEASE"); prefix != "" {
		relPrefix = prefix
	}

	relTag := strings.Replace(version, " ", "-", -1)
	relTag = strings.Replace(relTag, ":", "-", -1)
	relTag = strings.Replace(relTag, ",", "", -1)
	return relPrefix + "." + relTag
}

// commitID returns the abbreviated commit-id hash of the last commit.
func commitID() string {
	// git log --format="%h" -n1
	var (
		commit []byte
		e      error
	)
	cmdName := "git"
	cmdArgs := []string{"log", "--format=%H", "-n1"}
	if commit, e = exec.Command(cmdName, cmdArgs...).Output(); e != nil {
		fmt.Fprintln(os.Stderr, "Error generating git commit-id: ", e)
		os.Exit(1)
	}

	return strings.TrimSpace(string(commit))
}

func main() {
	fmt.Println(genLDFlags(time.Now().UTC().Format(time.RFC3339)))
}