Initial Commit

ops/registry/rollback.sh

@@ -0,0 +1,74 @@
+#!/usr/bin/env bash
+# rollback.sh — atomic-swap the live registry tree with the most
+# recent snapshot under /srv/registry/.previous/.
+#
+# Usage (on the OVH host, as deploy-registry or root):
+#   bash /srv/registry/ops/rollback.sh
+#
+# Idempotent within reason: a second invocation immediately after the
+# first promotes what was previously live (effectively roll-forward).
+# Exits non-zero with a clear message if no snapshot exists.
+
+set -euo pipefail
+
+REGISTRY_ROOT="${REGISTRY_ROOT:-/srv/registry}"
+LIVE_R="${REGISTRY_ROOT}/r"
+LIVE_SB="${REGISTRY_ROOT}/storybook"
+SNAPSHOT_ROOT="${REGISTRY_ROOT}/.previous"
+ROLLBACK_PARK="${REGISTRY_ROOT}/.rollback-park"
+
+log() {
+	printf '[rollback %s] %s\n' "$(date -u +%Y-%m-%dT%H:%M:%SZ)" "$*" >&2
+}
+
+err() {
+	log "ERROR: $*"
+	exit 1
+}
+
+if [[ ! -d "${SNAPSHOT_ROOT}" ]]; then
+	err "no snapshot directory at ${SNAPSHOT_ROOT}; nothing to roll back to"
+fi
+
+# Pick the most recent snapshot directory by name (ISO-8601 lexically sorts).
+LATEST="$(find "${SNAPSHOT_ROOT}" -mindepth 1 -maxdepth 1 -type d -printf '%f\n' 2>/dev/null | sort | tail -n 1)"
+
+if [[ -z "${LATEST}" ]]; then
+	err "no snapshots present under ${SNAPSHOT_ROOT}; cannot roll back"
+fi
+
+SNAPSHOT_DIR="${SNAPSHOT_ROOT}/${LATEST}"
+log "rolling back to snapshot: ${SNAPSHOT_DIR}"
+
+# Park the current tree as the next-snapshot so we can roll-forward
+# by re-running the script.
+PARK_DIR="${ROLLBACK_PARK}/$(date -u +%Y%m%dT%H%M%SZ)"
+mkdir -p "${PARK_DIR}"
+
+if [[ -d "${LIVE_R}" ]]; then
+	mv "${LIVE_R}" "${PARK_DIR}/r"
+fi
+if [[ -d "${LIVE_SB}" ]]; then
+	mv "${LIVE_SB}" "${PARK_DIR}/storybook"
+fi
+
+# Promote snapshot to live.
+if [[ -d "${SNAPSHOT_DIR}/r" ]]; then
+	mv "${SNAPSHOT_DIR}/r" "${LIVE_R}"
+fi
+if [[ -d "${SNAPSHOT_DIR}/storybook" ]]; then
+	mv "${SNAPSHOT_DIR}/storybook" "${LIVE_SB}"
+fi
+
+# Move the parked tree into the snapshots dir so the next rollback
+# call (a roll-forward) can find it.
+NEW_SNAPSHOT="${SNAPSHOT_ROOT}/$(basename "${PARK_DIR}")"
+mv "${PARK_DIR}" "${NEW_SNAPSHOT}"
+
+# Drained snapshot dir is now empty — clean up so next rollback picks
+# the right "latest".
+rmdir "${SNAPSHOT_DIR}" 2>/dev/null || true
+rmdir "${ROLLBACK_PARK}" 2>/dev/null || true
+
+log "rollback complete; live tree now serves contents from ${LATEST}"
+log "previous live tree parked at ${NEW_SNAPSHOT} (re-run to roll forward)"