Update feature gate logging to include default on

After the 5.7 release, when AutoUserSchemaCreate was graduated to
default on/true, we discovered that our current system (and the
underlying featuregate implementation) treats features explicitly
turned on by the user differently than features turned on by default.

This PR updates that logging to make clear that the features are those
specifically requested by the user (kept as a string to help debugging)
and revises the 'ShowGates' function to include those set through defaults.

Issues: [PGO-1824]

Author: benjaminjb

cmd/postgres-operator/main.go

@@ -134,7 +134,8 @@ func main() {
 
 	features := feature.NewGate()
 	assertNoError(features.Set(os.Getenv("PGO_FEATURE_GATES")))
-	log.Info("feature gates enabled", "PGO_FEATURE_GATES", features.String())
+	// This logs just the feature gates as set by the user
+	log.Info("feature gates enabled during deployment", "PGO_FEATURE_GATES", features.String())
 
 	cfg, err := runtime.GetConfig()
 	assertNoError(err)

internal/feature/features.go

@@ -42,6 +42,9 @@ package feature
 
 import (
 	"context"
+	"fmt"
+	"sort"
+	"strings"
 
 	"k8s.io/component-base/featuregate"
 )
@@ -52,6 +55,7 @@ type Feature = featuregate.Feature
 type Gate interface {
 	Enabled(Feature) bool
 	String() string
+	GetAll() map[Feature]featuregate.FeatureSpec
 }
 
 // MutableGate contains features that can be enabled or disabled.
@@ -122,11 +126,23 @@ func NewContext(ctx context.Context, gate Gate) context.Context {
 	return context.WithValue(ctx, contextKey{}, gate)
 }
 
+// ShowGates returns all the gates that are on by default
+// (if not turned off by the user) or were explicitly set
+// on by the user.
 func ShowGates(ctx context.Context) string {
-	featuresEnabled := ""
+	featuresEnabled := []string{}
 	gate, ok := ctx.Value(contextKey{}).(Gate)
 	if ok {
-		featuresEnabled = gate.String()
+		specs := gate.GetAll()
+		for feature := range specs {
+			// `gate.Enabled` first checks if the feature is enabled;
+			// then (if not explicitly set by the user),
+			// it checks if the feature is on/true by default
+			if gate.Enabled(feature) {
+				featuresEnabled = append(featuresEnabled, fmt.Sprintf("%s=true", feature))
+			}
+		}
 	}
-	return featuresEnabled
+	sort.Strings(featuresEnabled)
+	return strings.Join(featuresEnabled, ",")
 }

internal/feature/features_test.go

@@ -53,13 +53,21 @@ func TestContext(t *testing.T) {
 	t.Parallel()
 	gate := NewGate()
 	ctx := NewContext(context.Background(), gate)
-	assert.Equal(t, ShowGates(ctx), "")
+
+	// ShowGates returns all fields that are turned on, whether explicitly
+	// by the user or implicitly due to feature default.
+	// Currently, the only feature defaulting to true is `AutoCreateUserSchema`.
+	assert.Equal(t, ShowGates(ctx), "AutoCreateUserSchema=true")
 
 	assert.NilError(t, gate.Set("TablespaceVolumes=true"))
 	assert.Assert(t, true == Enabled(ctx, TablespaceVolumes))
-	assert.Equal(t, ShowGates(ctx), "TablespaceVolumes=true")
+	assert.Equal(t, ShowGates(ctx), "AutoCreateUserSchema=true,TablespaceVolumes=true")
 
-	assert.NilError(t, gate.SetFromMap(map[string]bool{TablespaceVolumes: false}))
+	assert.NilError(t, gate.SetFromMap(map[string]bool{
+		TablespaceVolumes:    false,
+		AutoCreateUserSchema: false,
+	}))
 	assert.Assert(t, false == Enabled(ctx, TablespaceVolumes))
-	assert.Equal(t, ShowGates(ctx), "TablespaceVolumes=false")
+	assert.Assert(t, false == Enabled(ctx, AutoCreateUserSchema))
+	assert.Equal(t, ShowGates(ctx), "")
 }

internal/upgradecheck/http_test.go

@@ -69,7 +69,7 @@ func TestCheckForUpgrades(t *testing.T) {
 		assert.Equal(t, data.RegistrationToken, "speakFriend")
 		assert.Equal(t, data.BridgeClustersTotal, 2)
 		assert.Equal(t, data.PGOClustersTotal, 2)
-		assert.Equal(t, data.FeatureGatesEnabled, "TablespaceVolumes=true")
+		assert.Equal(t, data.FeatureGatesEnabled, "AutoCreateUserSchema=true,TablespaceVolumes=true")
 	}
 
 	t.Run("success", func(t *testing.T) {