Shadow PostgreSQL promotion database preflight

ocf/loxthelion/managed-container.d/applications/postgresql/promote.sh

@@ -1,5 +1,63 @@
 # Sourced by managed-container; uses the shared OCF and parameter environment.
 
+mc_pg_promote_database_shadow()
+{
+    local socket_path resource response rc
+
+    socket_path="${MC_PROXY_SOCKET:-/run/user/1000/managed-containerd/managed-containerd.sock}"
+    resource="${OCF_RESOURCE_INSTANCE:-}"
+    resource="${resource%%:*}"
+
+    # Standalone/resource-agent tests may not have a real resource identity.
+    [ -n "${resource}" ] || return 0
+
+    if response="$(
+        timeout --kill-after=1s 5s \
+            python3 \
+            "${MC_PROXY_CLIENT:-/usr/lib/ocf/resource.d/loxthelion/managed-container.d/proxy_client.py}" \
+            "${socket_path}" \
+            "${resource}" \
+            "promote.database" \
+            10 \
+            11
+    )"; then
+        rc=0
+    else
+        rc=$?
+    fi
+
+    if [ "${rc}" -ne 0 ]; then
+        ocf_log warn \
+            "managed-containerd promote.database shadow unavailable rc=${rc}"
+        return 0
+    fi
+
+    if MC_DAEMON_RESPONSE="${response}" python3 -c '
+import json
+import os
+
+response = json.loads(os.environ["MC_DAEMON_RESPONSE"])
+
+if (
+    response.get("ocf_rc") != 0
+    or response.get("ready") is not True
+    or response.get("mutation") is not False
+):
+    raise SystemExit(1)
+'; then
+        ocf_log info \
+            "managed-containerd promote.database shadow: comparison=MATCH response=${response}"
+    else
+        ocf_log err \
+            "managed-containerd promote.database shadow MISMATCH response=${response}"
+    fi
+
+    # Shadow-only milestone: daemon disagreement must not alter the
+    # authoritative native promotion result yet.
+    return 0
+}
+
+
 managed_promote()
 {
     local monitor_rc role i
@@ -58,6 +116,11 @@ managed_promote()
     ocf_log info \
         "Promoting PostgreSQL standby inside ${CONTAINER_NAME}"
 
+    # Independent managed-containerd promotion preflight.
+    # Shadow-only for now: disagreement is logged but does not block
+    # the authoritative native PostgreSQL promotion.
+    mc_pg_promote_database_shadow
+
     if ! pg_command '
         BINDIR="$(pg_config --bindir)" || exit 1
         exec "$BINDIR/pg_ctl" \