efritz/ij

package environment

import (
    "fmt"
    "os/exec"
    "os/user"
    "regexp"
    "strings"
    "time"
)

const BuildTimeFormat = "2006-01-02T15:04:05-0700"

func Default() (Environment, error) {
    user, err := user.Current()
    if err != nil {
        return nil, err
    }

    lines := []string{
        fmt.Sprintf("UID=%s", user.Uid),
        fmt.Sprintf("GID=%s", user.Gid),
        fmt.Sprintf("BUILD_TIME=%s", formatNow()),
    }

    branch := gitOutput("rev-parse", "--abbrev-ref", "HEAD")
    remote := gitOutput("config", "--local", "remote.origin.url")
    commit := gitOutput("rev-parse", "HEAD")
    shortCommit := gitOutput("rev-parse", "--short", "HEAD")

    if commit != "" {
        lines = append(lines, fmt.Sprintf("GIT_BRANCH_NORMALIZED=%s", normalize(branch)))
        lines = append(lines, fmt.Sprintf("GIT_BRANCH=%s", branch))
        lines = append(lines, fmt.Sprintf("GIT_COMMIT_SHORT=%s", shortCommit))
        lines = append(lines, fmt.Sprintf("GIT_COMMIT=%s", commit))
        lines = append(lines, fmt.Sprintf("GIT_REMOTE=%s", remote))
    }

    return New(lines), nil
}

func formatNow() string {
    return time.Now().UTC().Format(BuildTimeFormat)
}

func normalize(value string) string {
    return regexp.MustCompile("[^._A-Za-z0-9-]").ReplaceAllLiteralString(value, "_")
}

func gitOutput(args ...string) string {
    out, err := exec.Command("git", args...).Output()
    if err != nil {
        return ""
    }

    return strings.TrimSpace(string(out))
}