version: Add a version command

contrib/completions/bash/runc

@@ -760,6 +760,7 @@ _runc() {
 		start
 		state
 		update
+		version
 		help
 		h
 	)

main.go

@@ -4,21 +4,11 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"strings"
 
 	"github.com/Sirupsen/logrus"
-	"github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/urfave/cli"
 )
 
-// version will be populated by the Makefile, read from
-// VERSION file of the source code.
-var version = ""
-
-// gitCommit will be the hash that the binary was built from
-// and will be populated by the Makefile
-var gitCommit = ""
-
 const (
 	specConfig = "config.json"
 	usage      = `Open Container Initiative runtime
@@ -50,16 +40,11 @@ func main() {
 	app := cli.NewApp()
 	app.Name = "runc"
 	app.Usage = usage
+	app.Version = ""
 
-	var v []string
-	if version != "" {
-		v = append(v, version)
-	}
-	if gitCommit != "" {
-		v = append(v, fmt.Sprintf("commit: %s", gitCommit))
+	cli.VersionPrinter = func(context *cli.Context) {
+		printVersion(context)
 	}
-	v = append(v, fmt.Sprintf("spec: %s", specs.Version))
-	app.Version = strings.Join(v, "\n")
 	app.Flags = []cli.Flag{
 		cli.BoolFlag{
 			Name:  "debug",
@@ -108,6 +93,7 @@ func main() {
 		startCommand,
 		stateCommand,
 		updateCommand,
+		versionCommand,
 	}
 	app.Before = func(context *cli.Context) error {
 		if context.GlobalBool("debug") {

man/runc-version.8.md

@@ -0,0 +1,14 @@
+# NAME
+   runc version - output the runtime version
+
+# SYNOPSIS
+   runc version
+
+Write version information to stdout and exit.
+
+# DESCRIPTION
+   The version command writes version information for runc and the
+supported spec release.  This information is also exposed through
+`runc --version`, and callers can use whichever is more convenient for
+them.
+

man/runc.8.md

@@ -44,6 +44,7 @@ value for "bundle" is the current directory.
    start        executes the user defined process in a created container
    state        output the state of a container
    update       update container resource constraints
+   version      output the runtime version
    help, h      Shows a list of commands or help for one command
 
 # GLOBAL OPTIONS

tests/integration/help.bats

@@ -7,11 +7,13 @@ load helpers
   [ "$status" -eq 0 ]
   [[ ${lines[0]} =~ NAME:+ ]]
   [[ ${lines[1]} =~ runc\ '-'\ Open\ Container\ Initiative\ runtime+ ]]
+  [ "${output}" = "${output/VERSION/}" ]
 
   runc --help
   [ "$status" -eq 0 ]
   [[ ${lines[0]} =~ NAME:+ ]]
   [[ ${lines[1]} =~ runc\ '-'\ Open\ Container\ Initiative\ runtime+ ]]
+  [ "${output}" = "${output/VERSION/}" ]
 }
 
 @test "runc command -h" {

tests/integration/version.bats

@@ -2,10 +2,18 @@
 
 load helpers
 
-@test "runc version" {
+@test "runc --version" {
   runc -v
   [ "$status" -eq 0 ]
-  [[ ${lines[0]} =~ runc\ version\ [0-9]+\.[0-9]+\.[0-9]+ ]]
+  [[ ${lines[0]} =~ runc\ [0-9]+\.[0-9]+\.[0-9]+ ]]
+  [[ ${lines[1]} =~ commit:+ ]]
+  [[ ${lines[2]} =~ spec:\ [0-9]+\.[0-9]+\.[0-9]+ ]]
+}
+
+@test "runc version" {
+  runc version
+  [ "$status" -eq 0 ]
+  [[ ${lines[0]} =~ runc\ [0-9]+\.[0-9]+\.[0-9]+ ]]
   [[ ${lines[1]} =~ commit:+ ]]
   [[ ${lines[2]} =~ spec:\ [0-9]+\.[0-9]+\.[0-9]+ ]]
 }

version.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/urfave/cli"
+)
+
+// version will be populated by the Makefile, read from
+// VERSION file of the source code.
+var version = ""
+
+// gitCommit will be the hash that the binary was built from
+// and will be populated by the Makefile
+var gitCommit = ""
+
+var versionCommand = cli.Command{
+	Name:        "version",
+	Usage:       "output the runtime version",
+	Description: `The version command outputs the runtime version.`,
+	Action:      printVersion,
+}
+
+func printVersion(context *cli.Context) (err error) {
+	if version == "" {
+		_, err = fmt.Print("runc unknown\n")
+	} else {
+		_, err = fmt.Printf("runc %s\n", version)
+	}
+	if err != nil {
+		return err
+	}
+	if gitCommit != "" {
+		_, err = fmt.Printf("commit: %s\n", gitCommit)
+		if err != nil {
+			return err
+		}
+	}
+	_, err = fmt.Printf("spec: %s\n", specs.Version)
+	return err
+}