feat: error early if min. supported version match

cmd/main.go

@@ -27,6 +27,7 @@ import (
 	"github.com/mercedes-benz/garm-operator/pkg/client"
 	"github.com/mercedes-benz/garm-operator/pkg/config"
 	"github.com/mercedes-benz/garm-operator/pkg/flags"
+	"github.com/mercedes-benz/garm-operator/pkg/version"
 )
 
 var (
@@ -129,6 +130,20 @@ func run() error {
 		return fmt.Errorf("unable to setup garm: %w", err)
 	}
 
+	// create a controller client to get controller info
+	// for the version check
+	controllerClient := client.NewControllerClient()
+	controllerInfo, err := controllerClient.GetControllerInfo()
+	if err != nil {
+		return fmt.Errorf("unable to get controller info: %w", err)
+	}
+
+	// if the version of the controller is not compatible with the Garm version
+	// return an error and stop the operator
+	if !version.EnsureMinimalVersion(controllerInfo.Payload.Version) {
+		return fmt.Errorf("garm-operator is not compatible with Garm version %s. Minimal required version is %s", controllerInfo.Payload.Version, version.MinVersion)
+	}
+
 	if err = (&garmcontroller.EnterpriseReconciler{
 		Client:   mgr.GetClient(),
 		Scheme:   mgr.GetScheme(),
@@ -273,5 +288,6 @@ func run() error {
 	if err := mgr.Start(ctx); err != nil {
 		return fmt.Errorf("unable to start manager: %w", err)
 	}
+
 	return nil
 }

go.mod

@@ -21,6 +21,7 @@ require (
 	github.com/spf13/pflag v1.0.5
 	github.com/stretchr/testify v1.9.0
 	go.uber.org/mock v0.5.0
+	golang.org/x/mod v0.18.0
 	gopkg.in/yaml.v2 v2.4.0
 	k8s.io/api v0.29.9
 	k8s.io/apimachinery v0.29.9

go.sum

@@ -207,6 +207,8 @@ golang.org/x/exp v0.0.0-20220722155223-a9213eeb770e h1:+WEEuIdZHnUeJJmEUjyYC2gfU
 golang.org/x/exp v0.0.0-20220722155223-a9213eeb770e/go.mod h1:Kr81I6Kryrl9sr8s2FK3vxD90NdsKWRuOIl2O4CvYbA=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
+golang.org/x/mod v0.18.0 h1:5+9lSbEzPSdWkH32vYPBwEpX8KwDbM52Ud9xBUvNlb0=
+golang.org/x/mod v0.18.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=

pkg/version/version.go

@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: MIT
+
+package version
+
+import "golang.org/x/mod/semver"
+
+const MinVersion = "v0.1.5"
+
+func EnsureMinimalVersion(version string) bool {
+	return semver.Compare(version, MinVersion) >= 0
+}

pkg/version/version_test.go

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: MIT
+
+package version
+
+import "testing"
+
+func TestCompare(t *testing.T) {
+
+	tests := []struct {
+		name    string
+		version string
+		isValid bool
+	}{
+		{
+			name:    "is equal",
+			version: "v0.1.5",
+			isValid: true,
+		},
+		{
+			name:    "garm is newer",
+			version: "v0.1.6",
+			isValid: true,
+		},
+		{
+			name:    "garm version to old",
+			version: "v0.1.4",
+			isValid: false,
+		},
+		{
+			name:    "garm is based on custom build without using build tags",
+			version: "v0.0.0-unknown.",
+			isValid: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := EnsureMinimalVersion(tt.version); got != tt.isValid {
+				t.Errorf("Compare() = %v, want %v", got, tt.isValid)
+			}
+		})
+	}
+}