mouthpiece/pkg/version.go

package mouthpiece

import (
	"encoding/json"
	"fmt"
	"os"
	"runtime"
	"runtime/debug"
	"strings"
	"text/tabwriter"
	"time"

	"github.com/common-nighthawk/go-figure"
)

const unknown = "unknown"

// Base version information.
//
// This is the fallback data used when version information from git is not
// provided via go ldflags.
var (
	// Output of "git describe". The prerequisite is that the
	// branch should be tagged using the correct versioning strategy.
	gitVersion = "devel"
	// SHA1 from git, output of $(git rev-parse HEAD)
	gitCommit = unknown
	// State of git tree, either "clean" or "dirty"
	gitTreeState = unknown
	// Build date in ISO8601 format, output of $(date -u +'%Y-%m-%dT%H:%M:%SZ')
	buildDate = unknown
	// flag to print the ascii name banner
	asciiName = "true"
	// goVersion is the used golang version.
	goVersion = unknown
	// compiler is the used golang compiler.
	compiler = unknown
	// platform is the used os/arch identifier.
	platform = unknown
)

type Info struct {
	GitVersion   string `json:"gitVersion"`
	GitCommit    string `json:"gitCommit"`
	GitTreeState string `json:"gitTreeState"`
	BuildDate    string `json:"buildDate"`
	GoVersion    string `json:"goVersion"`
	Compiler     string `json:"compiler"`
	Platform     string `json:"platform"`

	ASCIIName   string `json:"-"`
	FontName    string `json:"-"`
	Name        string `json:"-"`
	Description string `json:"-"`
}

func getBuildInfo() *debug.BuildInfo {
	bi, ok := debug.ReadBuildInfo()
	if !ok {
		return nil
	}
	return bi
}

func getGitVersion(bi *debug.BuildInfo) string {
	if bi == nil {
		return unknown
	}

	// TODO: remove this when the issue https://github.com/golang/go/issues/29228 is fixed
	if bi.Main.Version == "(devel)" || bi.Main.Version == "" {
		return gitVersion
	}

	return bi.Main.Version
}

func getCommit(bi *debug.BuildInfo) string {
	return getKey(bi, "vcs.revision")
}

func getDirty(bi *debug.BuildInfo) string {
	modified := getKey(bi, "vcs.modified")
	if modified == "true" {
		return "dirty"
	}
	if modified == "false" {
		return "clean"
	}
	return unknown
}

func getBuildDate(bi *debug.BuildInfo) string {
	buildTime := getKey(bi, "vcs.time")
	t, err := time.Parse("2006-01-02T15:04:05Z", buildTime)
	if err != nil {
		return unknown
	}
	return t.Format("2006-01-02T15:04:05")
}

func getKey(bi *debug.BuildInfo, key string) string {
	if bi == nil {
		return unknown
	}
	for _, iter := range bi.Settings {
		if iter.Key == key {
			return iter.Value
		}
	}
	return unknown
}

// GetVersionInfo represents known information on how this binary was built.
func GetVersionInfo() *Info {
	buildInfo := getBuildInfo()
	gitVersion = getGitVersion(buildInfo)
	if gitCommit == unknown {
		gitCommit = getCommit(buildInfo)
	}

	if gitTreeState == unknown {
		gitTreeState = getDirty(buildInfo)
	}

	if buildDate == unknown {
		buildDate = getBuildDate(buildInfo)
	}

	if goVersion == unknown {
		goVersion = runtime.Version()
	}

	if compiler == unknown {
		compiler = runtime.Compiler
	}

	if platform == unknown {
		platform = fmt.Sprintf("%s/%s", runtime.GOOS, runtime.GOARCH)
	}

	return &Info{
		ASCIIName:    asciiName,
		GitVersion:   gitVersion,
		GitCommit:    gitCommit,
		GitTreeState: gitTreeState,
		BuildDate:    buildDate,
		GoVersion:    goVersion,
		Compiler:     compiler,
		Platform:     platform,
	}
}

// String returns the string representation of the version info
func (i *Info) String() string {
	b := strings.Builder{}
	w := tabwriter.NewWriter(&b, 0, 0, 2, ' ', 0)

	// name and description are optional.
	if i.Name != "" {
		if i.ASCIIName == "true" {
			f := figure.NewFigure(strings.ToUpper(i.Name), i.FontName, true)
			_, _ = fmt.Fprint(w, f.String())
		}
		_, _ = fmt.Fprint(w, i.Name)
		if i.Description != "" {
			_, _ = fmt.Fprintf(w, ": %s", i.Description)
		}
		_, _ = fmt.Fprint(w, "\n\n")
	}

	_, _ = fmt.Fprintf(w, "GitVersion:\t%s\n", i.GitVersion)
	_, _ = fmt.Fprintf(w, "GitCommit:\t%s\n", i.GitCommit)
	_, _ = fmt.Fprintf(w, "GitTreeState:\t%s\n", i.GitTreeState)
	_, _ = fmt.Fprintf(w, "BuildDate:\t%s\n", i.BuildDate)
	_, _ = fmt.Fprintf(w, "GoVersion:\t%s\n", i.GoVersion)
	_, _ = fmt.Fprintf(w, "Compiler:\t%s\n", i.Compiler)
	_, _ = fmt.Fprintf(w, "Platform:\t%s\n", i.Platform)

	_ = w.Flush()
	return b.String()
}

// JSONString returns the JSON representation of the version info
func (i *Info) JSONString() (string, error) {
	b, err := json.MarshalIndent(i, "", "  ")
	if err != nil {
		return "", err
	}

	return string(b), nil
}

func (i *Info) CheckFontName(fontName string) bool {
	assetNames := figure.AssetNames()

	for _, font := range assetNames {
		if strings.Contains(font, fontName) {
			return true
		}
	}

	fmt.Fprintln(os.Stderr, "font not valid, using default")
	return false
}