infoutil: relax buildctl version format

Allow `buildctl github.com/moby/buildkit 0.0.0+unknown`

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

Author: AkihiroSuda

pkg/infoutil/infoutil.go

@@ -158,30 +158,48 @@ func ServerSemVer(ctx context.Context, client *containerd.Client) (*semver.Versi
 }
 
 func buildctlVersion() dockercompat.ComponentVersion {
-	const buildctl = "buildctl"
 	buildctlBinary, err := buildkitutil.BuildctlBinary()
 	if err != nil {
 		logrus.Warnf("unable to determine buildctl version: %s", err.Error())
-		return dockercompat.ComponentVersion{Name: buildctl}
+		return dockercompat.ComponentVersion{Name: "builctl"}
 	}
 
 	stdout, err := exec.Command(buildctlBinary, "--version").Output()
 	if err != nil {
 		logrus.Warnf("unable to determine buildctl version: %s", err.Error())
-		return dockercompat.ComponentVersion{Name: buildctl}
+		return dockercompat.ComponentVersion{Name: "buildctl"}
 	}
 
-	versionStr := strings.Fields(strings.TrimSpace(string(stdout)))
-	if len(versionStr) != 4 {
-		logrus.Errorf("unable to determine buildctl version got: %s", versionStr)
-		return dockercompat.ComponentVersion{Name: buildctl}
+	v, err := parseBuildctlVersion(stdout)
+	if err != nil {
+		logrus.Warn(err)
+		return dockercompat.ComponentVersion{Name: "buildctl"}
 	}
+	return *v
+}
 
-	return dockercompat.ComponentVersion{
-		Name:    buildctl,
-		Version: versionStr[2],
-		Details: map[string]string{"GitCommit": versionStr[3]},
+func parseBuildctlVersion(buildctlVersionStdout []byte) (*dockercompat.ComponentVersion, error) {
+	fields := strings.Fields(strings.TrimSpace(string(buildctlVersionStdout)))
+	var v *dockercompat.ComponentVersion
+	switch len(fields) {
+	case 4:
+		v = &dockercompat.ComponentVersion{
+			Name:    fields[0],
+			Version: fields[2],
+			Details: map[string]string{"GitCommit": fields[3]},
+		}
+	case 3:
+		v = &dockercompat.ComponentVersion{
+			Name:    fields[0],
+			Version: fields[2],
+		}
+	default:
+		return nil, fmt.Errorf("unable to determine buildctl version, got %q", string(buildctlVersionStdout))
+	}
+	if v.Name != "buildctl" {
+		return nil, fmt.Errorf("unable to determine buildctl version, got %q", string(buildctlVersionStdout))
 	}
+	return v, nil
 }
 
 func runcVersion() dockercompat.ComponentVersion {

pkg/infoutil/infoutil_test.go

@@ -0,0 +1,58 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package infoutil
+
+import (
+	"testing"
+
+	"github.com/containerd/nerdctl/pkg/inspecttypes/dockercompat"
+	"gotest.tools/v3/assert"
+)
+
+func TestParseBuildctlVersion(t *testing.T) {
+	testCases := map[string]*dockercompat.ComponentVersion{
+		"buildctl github.com/moby/buildkit v0.10.3 c8d25d9a103b70dc300a4fd55e7e576472284e31": {
+			Name:    "buildctl",
+			Version: "v0.10.3",
+			Details: map[string]string{
+				"GitCommit": "c8d25d9a103b70dc300a4fd55e7e576472284e31",
+			},
+		},
+		"buildctl github.com/moby/buildkit v0.10.0-380-g874eef9b 874eef9b70dbaf4f074d2bc8f4dc64237f8e83a0": {
+			Name:    "buildctl",
+			Version: "v0.10.0-380-g874eef9b",
+			Details: map[string]string{
+				"GitCommit": "874eef9b70dbaf4f074d2bc8f4dc64237f8e83a0",
+			},
+		},
+		"buildctl github.com/moby/buildkit 0.0.0+unknown": {
+			Name:    "buildctl",
+			Version: "0.0.0+unknown",
+		},
+		"foo bar baz": nil,
+	}
+
+	for s, expected := range testCases {
+		got, err := parseBuildctlVersion([]byte(s))
+		if expected != nil {
+			assert.NilError(t, err)
+			assert.DeepEqual(t, expected, got)
+		} else {
+			assert.Assert(t, err != nil)
+		}
+	}
+}