cli: add version validation and force flag

Version validation checks that the configured versions
are not more than one minor version below the CLI's version.
The validation can be disabled using --force.
This is necessary for now during development as the CLI
does not have a prerelease version, as our images do.

internal/config/validation_test.go

@@ -0,0 +1,51 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package config
+
+import (
+	"testing"
+
+	"github.com/edgelesssys/constellation/v2/internal/constants"
+	"github.com/stretchr/testify/assert"
+)
+
+// TestValidateVersionCompatibilityHelper checks that basic version and image short paths are correctly validated.
+func TestValidateVersionCompatibilityHelper(t *testing.T) {
+	testCases := map[string]struct {
+		cli       string
+		target    string
+		wantError bool
+	}{
+		"full version works": {
+			cli:    "v0.1.0",
+			target: "v0.0.0",
+		},
+		"short path works": {
+			cli:    "v0.1.0",
+			target: "ref/main/stream/debug/v0.0.0-pre.0.20230109121528-d24fac00f018",
+		},
+		"minor version difference > 1": {
+			cli:       "0.0.0",
+			target:    "ref/main/stream/debug/v0.2.0-pre.0.20230109121528-d24fac00f018",
+			wantError: true,
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			assert := assert.New(t)
+
+			constants.VersionInfo = tc.cli
+			err := validateVersionCompatibilityHelper("Image", tc.target)
+			if tc.wantError {
+				assert.Error(err)
+				return
+			}
+			assert.NoError(err)
+		})
+	}
+}