feat(version): print RootlessKit version in nerdctl version

pkg/infoutil/infoutil.go

@@ -122,6 +122,7 @@
 		Arch:      runtime.GOARCH,
 		Components: []dockercompat.ComponentVersion{
 			buildctlVersion(),
+			rootlesskitVersion(),
 		},
 	}
 }
@@ -232,6 +233,52 @@
 	}, nil
 }
 
+func rootlesskitVersion() dockercompat.ComponentVersion {
+	stdout, err := exec.Command("rootlesskit", "--version").Output()
+	if err != nil {
+		log.L.WithError(err).Warnf("unable to determine rootlesskit version")
+		return dockercompat.ComponentVersion{Name: "rootlesskit"}
+	}
+	v, err := parseRootlesskitVersion(stdout)
+	if err != nil {
+		log.L.Warn(err)
+		return dockercompat.ComponentVersion{Name: "rootlesskit"}
+	}
+	return *v
+}
+
+func parseRootlesskitVersion(rootlesskitVersionStdout []byte) (*dockercompat.ComponentVersion, error) {
+	var versionList = strings.Split(strings.TrimSpace(string(rootlesskitVersionStdout)), "\n")
+	if len(versionList) == 0 {
+		return nil, fmt.Errorf("unable to determine rootlesskit version, got: %s", string(rootlesskitVersionStdout))
+	}
+	firstLine := strings.Fields(versionList[0])
+	if len(firstLine) != 3 || firstLine[0] != "rootlesskit" {
+		return nil, fmt.Errorf("unable to determine rootlesskit version, got: %s", string(rootlesskitVersionStdout))
+	}
+	version := firstLine[2]
+
+	details := map[string]string{}
+	for _, detailsLine := range versionList[1:] {
+		detail := strings.SplitN(detailsLine, ":", 2)
+		if len(detail) != 2 {
+			log.L.Warnf("unable to determine one of rootlesskit details, got: %s, %d", detail, len(detail))
+			continue
+		}
+		switch strings.TrimSpace(detail[0]) {
+		case "commit":
+			details["GitCommit"] = strings.TrimSpace(detail[1])
+		}
+	}
+
+	return &dockercompat.ComponentVersion{
+		Name:    "rootlesskit",
+		Version: version,
+		Details: details,
+	}, nil
+}
+
+
 // getMobySysInfo returns the moby system info for the given cgroup manager
 func getMobySysInfo(cgroupManager string) *sysinfo.SysInfo {
 	var info dockercompat.Info

pkg/infoutil/infoutil_test.go

@@ -83,3 +83,31 @@ libseccomp: 2.5.1`: {
 		}
 	}
 }
+
+func TestParseRootlesskitVersion(t *testing.T) {
+	testCases := map[string]*dockercompat.ComponentVersion{
+		`rootlesskit version 2.0.2
+commit: 8d573c0b4b4b6e2e1c8e9044c4f8b4f3e2c1a0b1`: {
+			Name:    "rootlesskit",
+			Version: "2.0.2",
+			Details: map[string]string{
+				"GitCommit": "8d573c0b4b4b6e2e1c8e9044c4f8b4f3e2c1a0b1",
+			},
+		},
+		`rootlesskit version 1.1.1`: {
+			Name:    "rootlesskit",
+			Version: "1.1.1",
+		},
+		"foo bar baz": nil,
+	}
+
+	for s, expected := range testCases {
+		got, err := parseRootlesskitVersion([]byte(s))
+		if expected != nil {
+			assert.NilError(t, err)
+			assert.DeepEqual(t, expected, got)
+		} else {
+			assert.Assert(t, err != nil)
+		}
+	}
+}