vspd/internal/version/version.go
2023-09-29 09:20:53 +01:00

105 lines
2.8 KiB
Go

// Copyright (c) 2020 The Decred developers
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package version
import (
"bytes"
"fmt"
"runtime/debug"
"strings"
)
// semverAlphabet is an alphabet of all characters allowed in semver prerelease
// identifiers, and the . separator.
const semverAlphabet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-."
// Constants defining the application version number.
const (
major = 1
minor = 4
patch = 0
)
// preRelease contains the prerelease name of the application. It is a variable
// so it can be modified at link time (e.g.
// `-ldflags "-X decred.org/vspd/version.preRelease=rc1"`).
// It must only contain characters from the semantic version alphabet.
var preRelease = "pre"
func IsPreRelease() bool {
return preRelease != ""
}
// String returns the application version as a properly formed string per the
// semantic versioning 2.0.0 spec (https://semver.org/).
func String() string {
// Start with the major, minor, and path versions.
version := fmt.Sprintf("%d.%d.%d", major, minor, patch)
// Append pre-release version if there is one. The hyphen called for
// by the semantic versioning spec is automatically appended and should
// not be contained in the pre-release string. The pre-release version
// is not appended if it contains invalid characters.
preRelease := normalizeVerString(preRelease)
if preRelease != "" {
version = version + "-" + preRelease
}
buildMetadata := vcsCommitID()
// Append build metadata if there is any. The plus called for
// by the semantic versioning spec is automatically appended and should
// not be contained in the build metadata string. The build metadata
// string is not appended if it contains invalid characters.
buildMetadata = normalizeVerString(buildMetadata)
if buildMetadata != "" {
version = version + "+" + buildMetadata
}
return version
}
func vcsCommitID() string {
bi, ok := debug.ReadBuildInfo()
if !ok {
return ""
}
var vcs, revision string
for _, bs := range bi.Settings {
switch bs.Key {
case "vcs":
vcs = bs.Value
case "vcs.revision":
revision = bs.Value
}
}
if vcs == "" {
return ""
}
if vcs == "git" && len(revision) > 9 {
revision = revision[:9]
}
return revision
}
// normalizeVerString returns the passed string stripped of all characters which
// are not valid according to the semantic versioning guidelines for pre-release
// version and build metadata strings. In particular they MUST only contain
// characters in semanticAlphabet.
func normalizeVerString(str string) string {
var buf bytes.Buffer
for _, r := range str {
if strings.ContainsRune(semverAlphabet, r) {
_, err := buf.WriteRune(r)
// Writing to a bytes.Buffer panics on OOM, and all
// errors are unexpected.
if err != nil {
panic(err)
}
}
}
return buf.String()
}