rework version scheme with appBuild

api/apiroutes.go

@@ -127,7 +127,7 @@ func NewContext(client *rpcclient.Client, params *chaincfg.Params, dataSource Da
 			Height:          uint32(nodeHeight),
 			NodeConnections: conns,
 			APIVersion:      APIVersion,
-			DcrdataVersion:  appver.Ver.String(),
+			DcrdataVersion:  appver.Version(),
 		},
 		JSONIndent: JSONIndent,
 	}

config.go

@@ -295,7 +295,7 @@ func loadConfig() (*config, error) {
 	appName = strings.TrimSuffix(appName, filepath.Ext(appName))
 	if preCfg.ShowVersion {
 		fmt.Printf("%s version %s (Go version %s)\n", appName,
-			version.Ver.String(), runtime.Version())
+			version.Version(), runtime.Version())
 		os.Exit(0)
 	}
 

main.go

@@ -76,8 +76,8 @@ func mainCore() error {
 	}
 
 	// Start with version info
-	ver := &version.Ver
-	log.Infof("%s version %v (Go version %s)", version.AppName, ver, runtime.Version())
+	log.Infof("%s version %v (Go version %s)", version.AppName,
+		version.Version(), runtime.Version())
 
 	// PostgreSQL
 	usePG := cfg.FullMode
@@ -309,7 +309,7 @@ func mainCore() error {
 	mempoolSavers = append(mempoolSavers, baseDB.MPC)
 
 	// Create the explorer system
-	explore := explorer.New(&baseDB, auxDB, cfg.UseRealIP, ver.String(), !cfg.NoDevPrefetch)
+	explore := explorer.New(&baseDB, auxDB, cfg.UseRealIP, version.Version(), !cfg.NoDevPrefetch)
 	if explore == nil {
 		return fmt.Errorf("failed to create new explorer (templates missing?)")
 	}

version/version.go

@@ -1,34 +1,98 @@
+// Copyright (c) 2018 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 "fmt"
+import (
+	"bytes"
+	"fmt"
+	"strings"
+)
 
-type Version struct {
-	Major, Minor, Patch int
-	Label               string
-	Nick                string
-}
+const (
+	// semanticAlphabet defines the allowed characters for the pre-release
+	// portion of a semantic version string.
+	semanticAlphabet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-"
+
+	// semanticBuildAlphabet defines the allowed characters for the build
+	// portion of a semantic version string.
+	semanticBuildAlphabet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-."
+)
+
+// These constants define the application version and follow the semantic
+// versioning 2.0.0 spec (http://semver.org/).
+const (
+	AppName  string = "dcrdata"
+	AppMajor uint   = 3
+	AppMinor uint   = 0
+	AppPatch uint   = 0
+)
 
-var Ver = Version{
-	Major: 3,
-	Minor: 0,
-	Patch: 0,
-	Label: ""}
+// go build -ldflags "-X github.com/decred/dcrdata/version.appPreRelease= -X github.com/decred/dcrdata/version.appBuild=`git rev-parse --short HEAD`"
+var (
+	// appPreRelease is defined as a variable so it can be overridden during the
+	// build process. It MUST only contain characters from semanticAlphabet per
+	// the semantic versioning spec.
+	appPreRelease = "pre"
 
-// CommitHash may be set on the build command line:
-// go build -ldflags "-X github.com/decred/dcrdata/version.CommitHash=`git describe --abbrev=8 --long | awk -F "-" '{print $(NF-1)"-"$NF}'`"
-var CommitHash string
+	// appBuild is defined as a variable so it can be overridden during the
+	// build process. It MUST only contain characters from semanticBuildAlphabet
+	// per the semantic versioning spec.
+	appBuild = "dev"
+)
 
-const AppName string = "dcrdata"
+// Version returns the application version as a properly formed string per the
+// semantic versioning 2.0.0 spec (http://semver.org/).
+func Version() string {
+	// Start with the major, minor, and patch versions.
+	version := fmt.Sprintf("%d.%d.%d", AppMajor, AppMinor, AppPatch)
 
-func (v *Version) String() string {
-	var hashStr string
-	if CommitHash != "" {
-		hashStr = "+" + CommitHash
+	// 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 := normalizePreRelString(appPreRelease)
+	if preRelease != "" {
+		version = fmt.Sprintf("%s-%s", version, preRelease)
 	}
-	if v.Label != "" {
-		return fmt.Sprintf("%d.%d.%d-%s%s",
-			v.Major, v.Minor, v.Patch, v.Label, hashStr)
+
+	// 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.
+	build := normalizeBuildString(appBuild)
+	if build != "" {
+		version = fmt.Sprintf("%s+%s", version, build)
 	}
-	return fmt.Sprintf("%d.%d.%d%s",
-		v.Major, v.Minor, v.Patch, hashStr)
+
+	return version
+}
+
+// normalizeSemString returns the passed string stripped of all characters
+// which are not valid according to the provided semantic versioning alphabet.
+func normalizeSemString(str, alphabet string) string {
+	var result bytes.Buffer
+	for _, r := range str {
+		if strings.ContainsRune(alphabet, r) {
+			result.WriteRune(r)
+		}
+	}
+	return result.String()
+}
+
+// normalizePreRelString returns the passed string stripped of all characters
+// which are not valid according to the semantic versioning guidelines for
+// pre-release strings.  In particular they MUST only contain characters in
+// semanticAlphabet.
+func normalizePreRelString(str string) string {
+	return normalizeSemString(str, semanticAlphabet)
+}
+
+// normalizeBuildString returns the passed string stripped of all characters
+// which are not valid according to the semantic versioning guidelines for build
+// metadata strings.  In particular they MUST only contain characters in
+// semanticBuildAlphabet.
+func normalizeBuildString(str string) string {
+	return normalizeSemString(str, semanticBuildAlphabet)
 }