Introduces --json flag for k6 version sub-command (#4093)

* Introduces --json flag for k6 version sub-command

* Align terms with registry

* Moving version related logic to cmd

* Ensure that extension version match before grouping

* Simplify JSON details marshaling

cmd/root.go

@@ -19,7 +19,6 @@ import (
 	"go.k6.io/k6/cmd/state"
 	"go.k6.io/k6/errext"
 	"go.k6.io/k6/errext/exitcodes"
-	"go.k6.io/k6/lib/consts"
 	"go.k6.io/k6/log"
 )
 
@@ -79,7 +78,7 @@ func (c *rootCommand) persistentPreRunE(_ *cobra.Command, _ []string) error {
 	if err != nil {
 		return err
 	}
-	c.globalState.Logger.Debugf("k6 version: v%s", consts.FullVersion())
+	c.globalState.Logger.Debugf("k6 version: v%s", fullVersion())
 	return nil
 }
 

cmd/version.go

@@ -1,7 +1,10 @@
 package cmd
 
 import (
+	"encoding/json"
 	"fmt"
+	"runtime"
+	"runtime/debug"
 	"strings"
 
 	"github.com/spf13/cobra"
@@ -10,8 +13,89 @@ import (
 	"go.k6.io/k6/lib/consts"
 )
 
+const (
+	commitKey      = "commit"
+	commitDirtyKey = "commit_dirty"
+)
+
+// fullVersion returns the maximally full version and build information for
+// the currently running k6 executable.
+func fullVersion() string {
+	details := versionDetails()
+
+	goVersionArch := fmt.Sprintf("%s, %s/%s", details["go_version"], details["go_os"], details["go_arch"])
+
+	k6version := fmt.Sprintf("%s", details["version"])
+	// for the fallback case when the version is not in the expected format
+	// cobra adds a "v" prefix to the version
+	k6version = strings.TrimLeft(k6version, "v")
+
+	commit, ok := details[commitKey].(string)
+	if !ok || commit == "" {
+		return fmt.Sprintf("%s (%s)", k6version, goVersionArch)
+	}
+
+	isDirty, ok := details[commitDirtyKey].(bool)
+	if ok && isDirty {
+		commit += "-dirty"
+	}
+
+	return fmt.Sprintf("%s (commit/%s, %s)", k6version, commit, goVersionArch)
+}
+
+// versionDetails returns the structured details about version
+func versionDetails() map[string]interface{} {
+	v := consts.Version
+	if !strings.HasPrefix(v, "v") {
+		v = "v" + v
+	}
+
+	details := map[string]interface{}{
+		"version":    v,
+		"go_version": runtime.Version(),
+		"go_os":      runtime.GOOS,
+		"go_arch":    runtime.GOARCH,
+	}
+
+	buildInfo, ok := debug.ReadBuildInfo()
+	if !ok {
+		return details
+	}
+
+	var (
+		commit string
+		dirty  bool
+	)
+	for _, s := range buildInfo.Settings {
+		switch s.Key {
+		case "vcs.revision":
+			commitLen := 10
+			if len(s.Value) < commitLen {
+				commitLen = len(s.Value)
+			}
+			commit = s.Value[:commitLen]
+		case "vcs.modified":
+			if s.Value == "true" {
+				dirty = true
+			}
+		default:
+		}
+	}
+
+	if commit == "" {
+		return details
+	}
+
+	details[commitKey] = commit
+	if dirty {
+		details[commitDirtyKey] = true
+	}
+
+	return details
+}
+
 func versionString() string {
-	v := consts.FullVersion()
+	v := fullVersion()
 
 	if exts := ext.GetAll(); len(exts) > 0 {
 		extsDesc := make([]string, 0, len(exts))
@@ -24,16 +108,70 @@ func versionString() string {
 	return v
 }
 
-func getCmdVersion(_ *state.GlobalState) *cobra.Command {
-	// versionCmd represents the version command.
-	return &cobra.Command{
+type versionCmd struct {
+	gs     *state.GlobalState
+	isJSON bool
+}
+
+func (c *versionCmd) run(cmd *cobra.Command, _ []string) error {
+	if !c.isJSON {
+		root := cmd.Root()
+		root.SetArgs([]string{"--version"})
+		_ = root.Execute()
+		return nil
+	}
+
+	details := versionDetails()
+	if exts := ext.GetAll(); len(exts) > 0 {
+		type extInfo struct {
+			Module  string   `json:"module"`
+			Version string   `json:"version"`
+			Imports []string `json:"imports"`
+		}
+
+		ext := make(map[string]extInfo)
+		for _, e := range exts {
+			key := e.Path + "@" + e.Version
+
+			if v, ok := ext[key]; ok {
+				v.Imports = append(v.Imports, e.Name)
+				ext[key] = v
+				continue
+			}
+
+			ext[key] = extInfo{
+				Module:  e.Path,
+				Version: e.Version,
+				Imports: []string{e.Name},
+			}
+		}
+
+		list := make([]extInfo, 0, len(ext))
+		for _, v := range ext {
+			list = append(list, v)
+		}
+
+		details["extensions"] = list
+	}
+
+	if err := json.NewEncoder(c.gs.Stdout).Encode(details); err != nil {
+		return fmt.Errorf("failed to encode/output version details: %w", err)
+	}
+
+	return nil
+}
+
+func getCmdVersion(gs *state.GlobalState) *cobra.Command {
+	versionCmd := &versionCmd{gs: gs}
+
+	cmd := &cobra.Command{
 		Use:   "version",
 		Short: "Show application version",
 		Long:  `Show the application version and exit.`,
-		Run: func(cmd *cobra.Command, _ []string) {
-			root := cmd.Root()
-			root.SetArgs([]string{"--version"})
-			_ = root.Execute()
-		},
+		RunE:  versionCmd.run,
 	}
+
+	cmd.Flags().BoolVar(&versionCmd.isJSON, "json", false, "if set, output version information will be in JSON format")
+
+	return cmd
 }

cmd/version_test.go

@@ -0,0 +1,82 @@
+package cmd
+
+import (
+	"encoding/json"
+	"runtime"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"go.k6.io/k6/cmd/tests"
+	"go.k6.io/k6/lib/consts"
+)
+
+func TestVersionFlag(t *testing.T) {
+	t.Parallel()
+
+	ts := tests.NewGlobalTestState(t)
+	ts.ExpectedExitCode = 0
+	ts.CmdArgs = []string{"k6", "--version"}
+
+	ExecuteWithGlobalState(ts.GlobalState)
+
+	stdout := ts.Stdout.String()
+	t.Log(stdout)
+	assert.NotEmpty(t, stdout)
+
+	// Check that the version/format string is correct
+	assert.Contains(t, stdout, "k6 v")
+	assert.Contains(t, stdout, consts.Version)
+	assert.Contains(t, stdout, runtime.Version())
+	assert.Contains(t, stdout, runtime.GOOS)
+	assert.Contains(t, stdout, runtime.GOARCH)
+}
+
+func TestVersionSubCommand(t *testing.T) {
+	t.Parallel()
+
+	ts := tests.NewGlobalTestState(t)
+	ts.ExpectedExitCode = 0
+	ts.CmdArgs = []string{"k6", "version"}
+
+	ExecuteWithGlobalState(ts.GlobalState)
+
+	stdout := ts.Stdout.String()
+	t.Log(stdout)
+	assert.NotEmpty(t, stdout)
+
+	// Check that the version/format string is correct
+	assert.Contains(t, stdout, "k6 v")
+	assert.Contains(t, stdout, consts.Version)
+	assert.Contains(t, stdout, runtime.Version())
+	assert.Contains(t, stdout, runtime.GOOS)
+	assert.Contains(t, stdout, runtime.GOARCH)
+}
+
+func TestVersionJSONSubCommand(t *testing.T) {
+	t.Parallel()
+
+	ts := tests.NewGlobalTestState(t)
+	ts.ExpectedExitCode = 0
+	ts.CmdArgs = []string{"k6", "version", "--json"}
+
+	ExecuteWithGlobalState(ts.GlobalState)
+
+	stdout := ts.Stdout.String()
+	t.Log(stdout)
+	assert.NotEmpty(t, stdout)
+
+	// try to unmarshal the JSON output
+	var details map[string]interface{}
+	err := json.Unmarshal([]byte(stdout), &details)
+	assert.NoError(t, err)
+
+	// Check that details are correct
+	assert.Contains(t, details, "version")
+	assert.Contains(t, details, "go_version")
+	assert.Contains(t, details, "go_os")
+	assert.Contains(t, details, "go_arch")
+	assert.Equal(t, "v"+consts.Version, details["version"])
+	assert.Equal(t, runtime.Version(), details["go_version"])
+	assert.Equal(t, runtime.GOOS, details["go_os"])
+	assert.Equal(t, runtime.GOARCH, details["go_arch"])
+}

lib/consts/consts.go

@@ -2,56 +2,12 @@
 package consts
 
 import (
-	"fmt"
-	"runtime"
-	"runtime/debug"
 	"strings"
 )
 
 // Version contains the current semantic version of k6.
 const Version = "0.55.0"
 
-// FullVersion returns the maximally full version and build information for
-// the currently running k6 executable.
-func FullVersion() string {
-	goVersionArch := fmt.Sprintf("%s, %s/%s", runtime.Version(), runtime.GOOS, runtime.GOARCH)
-
-	buildInfo, ok := debug.ReadBuildInfo()
-	if !ok {
-		return fmt.Sprintf("%s (%s)", Version, goVersionArch)
-	}
-
-	var (
-		commit string
-		dirty  bool
-	)
-	for _, s := range buildInfo.Settings {
-		switch s.Key {
-		case "vcs.revision":
-			commitLen := 10
-			if len(s.Value) < commitLen {
-				commitLen = len(s.Value)
-			}
-			commit = s.Value[:commitLen]
-		case "vcs.modified":
-			if s.Value == "true" {
-				dirty = true
-			}
-		default:
-		}
-	}
-
-	if commit == "" {
-		return fmt.Sprintf("%s (%s)", Version, goVersionArch)
-	}
-
-	if dirty {
-		commit += "-dirty"
-	}
-
-	return fmt.Sprintf("%s (commit/%s, %s)", Version, commit, goVersionArch)
-}
-
 // Banner returns the ASCII-art banner with the k6 logo
 func Banner() string {
 	banner := strings.Join([]string{