Create warning event when postgres version is EOL.

internal/controller/postgrescluster/controller.go

@@ -136,6 +136,16 @@ func (r *Reconciler) Reconcile(
 			return runtime.ErrorWithBackoff(err)
 		}
 	}
+	// Issue Warning Event if postgres version is EOL according to PostgreSQL:
+	// https://www.postgresql.org/support/versioning/
+	currentTime := time.Now()
+	if postgres.ReleaseIsFinal(cluster.Spec.PostgresVersion, currentTime) {
+		r.Recorder.Eventf(cluster, corev1.EventTypeWarning, "EndOfLifePostgresVersion",
+			"The last minor version of Postgres %[1]v has been released."+
+				" PG %[1]v will no longer receive updates. We recommend upgrading."+
+				" See https://www.postgresql.org/support/versioning",
+			cluster.Spec.PostgresVersion)
+	}
 
 	if cluster.Spec.Standby != nil &&
 		cluster.Spec.Standby.Enabled &&

internal/controller/postgrescluster/controller_test.go

@@ -556,4 +556,66 @@ spec:
 			Expect(instance.Spec.Replicas).To(PointTo(BeEquivalentTo(1)))
 		})
 	})
+
+	Context("Postgres version EOL", func() {
+		var cluster *v1beta1.PostgresCluster
+
+		BeforeEach(func() {
+			cluster = create(`
+metadata:
+  name: old-postgres
+spec:
+  postgresVersion: 11
+  image: postgres
+  instances:
+  - name: instance1
+    dataVolumeClaimSpec:
+      accessModes:
+      - "ReadWriteMany"
+      resources:
+        requests:
+          storage: 1Gi
+  backups:
+    pgbackrest:
+      image: pgbackrest
+      repos:
+      - name: repo1
+        volume:
+          volumeClaimSpec:
+            accessModes:
+            - "ReadWriteOnce"
+            resources:
+              requests:
+                storage: 1Gi
+`)
+			Expect(reconcile(cluster)).To(BeZero())
+		})
+
+		AfterEach(func() {
+			ctx := context.Background()
+
+			if cluster != nil {
+				Expect(client.IgnoreNotFound(
+					suite.Client.Delete(ctx, cluster),
+				)).To(Succeed())
+
+				// Remove finalizers, if any, so the namespace can terminate.
+				Expect(client.IgnoreNotFound(
+					suite.Client.Patch(ctx, cluster, client.RawPatch(
+						client.Merge.Type(), []byte(`{"metadata":{"finalizers":[]}}`))),
+				)).To(Succeed())
+			}
+		})
+
+		Specify("Postgres EOL Warning Event", func() {
+			existing := &v1beta1.PostgresCluster{}
+			Expect(suite.Client.Get(
+				context.Background(), client.ObjectKeyFromObject(cluster), existing,
+			)).To(Succeed())
+
+			event, ok := <-test.Recorder.Events
+			Expect(ok).To(BeTrue())
+			Expect(event).To(ContainSubstring("PG 11 will no longer receive updates. We recommend upgrading."))
+		})
+	})
 })

internal/postgres/versions.go

@@ -0,0 +1,26 @@
+// Copyright 2021 - 2024 Crunchy Data Solutions, Inc.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package postgres
+
+import "time"
+
+// https://www.postgresql.org/support/versioning
+var finalReleaseDates = map[int]time.Time{
+	10: time.Date(2022, time.November+1, 10, 0, 0, 0, 0, time.UTC),
+	11: time.Date(2023, time.November+1, +9, 0, 0, 0, 0, time.UTC),
+	12: time.Date(2024, time.November+1, 14, 0, 0, 0, 0, time.UTC),
+	13: time.Date(2025, time.November+1, 13, 0, 0, 0, 0, time.UTC),
+	14: time.Date(2026, time.November+1, 12, 0, 0, 0, 0, time.UTC),
+	15: time.Date(2027, time.November+1, 11, 0, 0, 0, 0, time.UTC),
+	16: time.Date(2028, time.November+1, +9, 0, 0, 0, 0, time.UTC),
+	17: time.Date(2029, time.November+1, +8, 0, 0, 0, 0, time.UTC),
+}
+
+// ReleaseIsFinal returns whether or not t is definitively past the final
+// scheduled release of a Postgres version.
+func ReleaseIsFinal(majorVersion int, t time.Time) bool {
+	known, ok := finalReleaseDates[majorVersion]
+	return ok && t.After(known)
+}

internal/postgres/versions_test.go

@@ -0,0 +1,34 @@
+// Copyright 2021 - 2024 Crunchy Data Solutions, Inc.
+//
+// SPDX-License-Identifier: Apache-2.0
+
+package postgres
+
+import (
+	"testing"
+	"time"
+
+	"gotest.tools/v3/assert"
+)
+
+func TestReleaseIsFinal(t *testing.T) {
+	// On November 4th, 2024, PG 10 and 11 were EOL and 12-17 were supported.
+	testDate, err := time.Parse("2006-Jan-02", "2024-Nov-04")
+	assert.NilError(t, err)
+	assert.Check(t, ReleaseIsFinal(10, testDate))
+	assert.Check(t, ReleaseIsFinal(11, testDate))
+	assert.Check(t, !ReleaseIsFinal(12, testDate))
+	assert.Check(t, !ReleaseIsFinal(13, testDate))
+	assert.Check(t, !ReleaseIsFinal(14, testDate))
+	assert.Check(t, !ReleaseIsFinal(15, testDate))
+	assert.Check(t, !ReleaseIsFinal(16, testDate))
+	assert.Check(t, !ReleaseIsFinal(17, testDate))
+
+	// On December 15th, 2024 we alert that PG 12 is EOL
+	testDate = testDate.AddDate(0, 1, 11)
+	assert.Check(t, ReleaseIsFinal(12, testDate))
+
+	// ReleaseIsFinal covers PG versions 10 and greater. Any version not covered
+	// by the case statement in ReleaseIsFinal returns false
+	assert.Check(t, !ReleaseIsFinal(1, testDate))
+}