fix for etcd-io#19066 Print warnings when deprecated options are conf…

…igured in config file

Signed-off-by: mansoora <[email protected]>

server/etcdmain/config_test.go

@@ -653,3 +653,98 @@ func validateClusteringFlags(t *testing.T, cfg *config) {
 		t.Errorf("advertise-client-urls = %v, want %v", cfg.ec.AdvertiseClientUrls, wcfg.ec.AdvertiseClientUrls)
 	}
 }
+
+func TestConfigFileDeprecatedOptions(t *testing.T) {
+	type configStruct struct {
+		SnapshotCount                           uint64        `json:"snapshot-count,omitempty"`
+		MaxSnapFiles                            uint          `json:"max-snapshots,omitempty"`
+		V2Deprecation                           string        `json:"v2-deprecation,omitempty"`
+		ExperimentalCompactHashCheckEnabled     bool          `json:"experimental-compact-hash-check-enabled,omitempty"`
+		ExperimentalCompactHashCheckTime        time.Duration `json:"experimental-compact-hash-check-time,omitempty"`
+		ExperimentalWarningUnaryRequestDuration time.Duration `json:"experimental-warning-unary-request-duration,omitempty"`
+	}
+
+	testCases := []struct {
+		name             string
+		configFileYAML   configStruct
+		expectedWarnings []string
+	}{
+		{
+			name:             "no deprecated options",
+			configFileYAML:   configStruct{},
+			expectedWarnings: nil,
+		},
+		{
+			name: "deprecated experimental options",
+			configFileYAML: configStruct{
+				ExperimentalCompactHashCheckEnabled:     true,
+				ExperimentalCompactHashCheckTime:        2 * time.Minute,
+				ExperimentalWarningUnaryRequestDuration: time.Second,
+			},
+			expectedWarnings: []string{
+				"experimental-compact-hash-check-enabled is deprecated in v3.6 and will be decommissioned in v3.7. Use '--feature-gates=CompactHashCheck=true' instead",
+				"experimental-compact-hash-check-time is deprecated in v3.6 and will be decommissioned in v3.7. Use --compact-hash-check-time instead",
+				"experimental-warning-unary-request-duration is deprecated, and will be decommissioned in v3.7. Use warning-unary-request-duration instead",
+			},
+		},
+		{
+			name: "deprecated snapshot options",
+			configFileYAML: configStruct{
+				SnapshotCount: 10000,
+				MaxSnapFiles:  5,
+			},
+			expectedWarnings: []string{
+				"snapshot-count is deprecated in v3.6 and will be decommissioned in v3.7",
+				"max-snapshots is deprecated in v3.6 and will be decommissioned in v3.7",
+			},
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			b, err := yaml.Marshal(&tc.configFileYAML)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			tmpfile := mustCreateCfgFile(t, b)
+			defer os.Remove(tmpfile.Name())
+
+			cfg := newConfig()
+			err = cfg.parse([]string{fmt.Sprintf("--config-file=%s", tmpfile.Name())})
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			// Check if the expected flags were marked as deprecated
+			for flagName := range cfg.ec.FlagsExplicitlySet {
+				if msg, ok := deprecatedFlags[flagName]; ok {
+					found := false
+					for _, expected := range tc.expectedWarnings {
+						if msg == expected {
+							found = true
+							break
+						}
+					}
+					if !found {
+						t.Errorf("unexpected deprecated flag warning for %q: %q", flagName, msg)
+					}
+				}
+			}
+
+			// Check if all expected warnings were present
+			for _, expected := range tc.expectedWarnings {
+				found := false
+				for flagName := range cfg.ec.FlagsExplicitlySet {
+					if msg, ok := deprecatedFlags[flagName]; ok && msg == expected {
+						found = true
+						break
+					}
+				}
+				if !found {
+					t.Errorf("missing expected warning: %q", expected)
+				}
+			}
+		})
+	}
+}