From 10df575ef72481117866eb81f691915b465a1aa3 Mon Sep 17 00:00:00 2001
From: Ednunp <ednunp@gmail.com>
Date: Fri, 15 May 2026 17:24:27 +0100
Subject: [PATCH] =?UTF-8?q?server:=20update=20to=20v2.3=20=E2=80=94=20dual?=
 =?UTF-8?q?-protocol=20relay=20(v1=20pair=20+=20v2=20lobby)=20+=20auto-upd?=
 =?UTF-8?q?ater=20with=20EXIT=20trap=20fix?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 server/remsound-relay-update.sh | 358 ++++++++++++++++++++++++++++++++
 1 file changed, 358 insertions(+)
 create mode 100644 server/remsound-relay-update.sh

diff --git a/server/remsound-relay-update.sh b/server/remsound-relay-update.sh
new file mode 100644
index 0000000..0dba8a3
--- /dev/null
+++ b/server/remsound-relay-update.sh
@@ -0,0 +1,358 @@
+#!/bin/bash
+# remsound-relay-update.sh — periodic GitHub-release-based updater for the
+# RemSound relay. Designed to run from a systemd .timer; safe to run by hand
+# too. Idempotent: if there is no newer release, exits 0 quickly with no
+# system changes.
+#
+# What it does:
+#   1. Read the installed tag from /etc/remsound-relay/version.
+#   2. Query the GitHub Releases API for tags starting with "server-".
+#   3. If the latest is newer than the installed tag:
+#      a. Download the matching tarball asset.
+#      b. Snapshot current installed files to /etc/remsound-relay/backup/.
+#      c. Stop the relay service.
+#      d. Replace the relay files with the new tarball contents.
+#      e. systemctl daemon-reload + start.
+#      f. Wait 3s and check the service is active.
+#         If yes: write the new tag, log success, exit 0.
+#         If no:  restore from backup, restart, log failure, exit 1.
+#   4. Log everything to /var/log/remsound-relay-update.log.
+#
+# Failure modes are defensive — a broken updater run leaves the previously
+# installed version running, never less.
+
+set -euo pipefail
+
+# -------- configuration ------------------------------------------------------
+
+REPO="${REMSOUND_UPDATE_REPO:-Ednunp/RemSound}"
+TAG_PREFIX="${REMSOUND_UPDATE_TAG_PREFIX:-server-}"
+ASSET_PATTERN="${REMSOUND_UPDATE_ASSET_PATTERN:-remsound-server-.*\.tar\.gz$}"
+
+INSTALL_BIN="/usr/local/sbin/remsound-relay.py"
+INSTALL_UPDATER="/usr/local/sbin/remsound-relay-update.sh"
+INSTALL_SERVICE="/etc/systemd/system/remsound-relay.service"
+INSTALL_UPDATE_SERVICE="/etc/systemd/system/remsound-relay-update.service"
+INSTALL_UPDATE_TIMER="/etc/systemd/system/remsound-relay-update.timer"
+
+STATE_DIR="/etc/remsound-relay"
+VERSION_FILE="$STATE_DIR/version"
+BACKUP_DIR="$STATE_DIR/backup"
+LOG_FILE="/var/log/remsound-relay-update.log"
+
+SERVICE_NAME="remsound-relay.service"
+HEALTH_WAIT_SECONDS=3
+
+# Script-global mktemp working directory. Set by main(); cleaned up by the
+# EXIT trap below. Kept at script scope (not function-local) so the trap can
+# still see it under `set -u` after main returns.
+WORK_DIR=""
+
+cleanup_work_dir() {
+    if [[ -n "$WORK_DIR" && -d "$WORK_DIR" ]]; then
+        rm -rf "$WORK_DIR"
+    fi
+}
+trap cleanup_work_dir EXIT
+
+# -------- helpers ------------------------------------------------------------
+
+log() {
+    local ts msg
+    ts="$(date '+%Y-%m-%d %H:%M:%S')"
+    msg="$ts $*"
+    printf '%s\n' "$msg" | tee -a "$LOG_FILE" >&2
+}
+
+require_root() {
+    if [[ $EUID -ne 0 ]]; then
+        log "ERROR: this script must run as root"
+        exit 1
+    fi
+}
+
+ensure_dirs() {
+    mkdir -p "$STATE_DIR" "$BACKUP_DIR" "$(dirname "$LOG_FILE")"
+    touch "$LOG_FILE"
+}
+
+read_current_version() {
+    if [[ -f "$VERSION_FILE" ]]; then
+        local v
+        v="$(tr -d '[:space:]' < "$VERSION_FILE")"
+        if [[ -n "$v" ]]; then
+            printf '%s' "$v"
+            return
+        fi
+    fi
+    printf '%s' "${TAG_PREFIX}v0"
+}
+
+# Parse a tag like "server-v2.10" into a comparable numeric form.
+# Outputs MAJOR.MINOR; both default to 0 if the tag is unparseable.
+tag_to_version() {
+    local tag="$1"
+    # strip the prefix
+    tag="${tag#"$TAG_PREFIX"}"
+    # strip a leading "v" if present
+    tag="${tag#v}"
+    local major minor
+    major="${tag%%.*}"
+    minor="${tag#*.}"
+    # if there's no dot, minor==major. Treat as MAJOR.0.
+    if [[ "$minor" == "$tag" ]]; then
+        minor="0"
+    fi
+    # keep only digits — survive things like "v2.0-rc1" by ignoring the suffix.
+    major="${major//[^0-9]/}"
+    minor="${minor//[^0-9]/}"
+    : "${major:=0}"
+    : "${minor:=0}"
+    printf '%s.%s' "$major" "$minor"
+}
+
+# Returns 0 if $1 > $2 (i.e. left tag is newer), 1 otherwise.
+tag_newer_than() {
+    local left right lv rv
+    left="$(tag_to_version "$1")"
+    right="$(tag_to_version "$2")"
+    # Numeric compare major then minor.
+    lv="${left%.*}"; rv="${right%.*}"
+    if (( lv > rv )); then return 0; fi
+    if (( lv < rv )); then return 1; fi
+    lv="${left#*.}"; rv="${right#*.}"
+    if (( lv > rv )); then return 0; fi
+    return 1
+}
+
+# -------- GitHub releases query ---------------------------------------------
+
+# Fetch the releases list and pick the latest server-tag release.
+# Outputs three lines: tag, asset_url, asset_name. Exits non-zero on no match.
+get_latest_release() {
+    local json
+    if ! json="$(curl --fail --silent --show-error --max-time 30 \
+        -H "Accept: application/vnd.github+json" \
+        "https://api.github.com/repos/${REPO}/releases?per_page=30" 2>&1)"; then
+        log "ERROR: failed to query GitHub releases: $json"
+        return 2
+    fi
+
+    REPO="$REPO" TAG_PREFIX="$TAG_PREFIX" ASSET_PATTERN="$ASSET_PATTERN" \
+    python3 - "$json" <<'PY'
+import json, os, re, sys
+
+raw = sys.argv[1] if len(sys.argv) > 1 else ""
+prefix = os.environ.get("TAG_PREFIX", "server-")
+asset_re = re.compile(os.environ.get("ASSET_PATTERN", r"remsound-server-.*\.tar\.gz$"))
+
+try:
+    releases = json.loads(raw)
+except Exception as exc:
+    sys.stderr.write(f"json parse failed: {exc}\n")
+    sys.exit(3)
+
+if not isinstance(releases, list):
+    sys.stderr.write(f"unexpected releases response shape\n")
+    sys.exit(3)
+
+def parse_version(tag):
+    # strip prefix
+    if tag.startswith(prefix):
+        tag = tag[len(prefix):]
+    if tag.startswith("v"):
+        tag = tag[1:]
+    parts = tag.split(".")
+    out = []
+    for p in parts:
+        digits = "".join(c for c in p if c.isdigit())
+        out.append(int(digits) if digits else 0)
+    if len(out) < 2:
+        out.append(0)
+    return tuple(out)
+
+candidates = []
+for r in releases:
+    if not isinstance(r, dict):
+        continue
+    tag = r.get("tag_name") or ""
+    if not tag.startswith(prefix):
+        continue
+    if r.get("draft") or r.get("prerelease"):
+        continue
+    asset = None
+    for a in r.get("assets") or []:
+        name = (a or {}).get("name") or ""
+        if asset_re.search(name):
+            asset = a
+            break
+    if asset is None:
+        continue
+    url = asset.get("browser_download_url") or ""
+    name = asset.get("name") or ""
+    if not url:
+        continue
+    candidates.append((parse_version(tag), tag, url, name))
+
+if not candidates:
+    sys.stderr.write("no eligible server-* releases found\n")
+    sys.exit(4)
+
+candidates.sort(reverse=True)
+_, tag, url, name = candidates[0]
+print(tag)
+print(url)
+print(name)
+PY
+}
+
+# -------- backup + install ---------------------------------------------------
+
+snapshot_backup() {
+    log "snapshotting current install to $BACKUP_DIR"
+    rm -rf "$BACKUP_DIR"
+    mkdir -p "$BACKUP_DIR"
+    for f in \
+        "$INSTALL_BIN" "$INSTALL_UPDATER" \
+        "$INSTALL_SERVICE" "$INSTALL_UPDATE_SERVICE" "$INSTALL_UPDATE_TIMER" \
+        "$VERSION_FILE"
+    do
+        if [[ -f "$f" ]]; then
+            cp -a "$f" "$BACKUP_DIR/$(basename "$f")"
+        fi
+    done
+}
+
+restore_backup() {
+    log "rolling back from $BACKUP_DIR"
+    for f in \
+        "$INSTALL_BIN" "$INSTALL_UPDATER" \
+        "$INSTALL_SERVICE" "$INSTALL_UPDATE_SERVICE" "$INSTALL_UPDATE_TIMER" \
+        "$VERSION_FILE"
+    do
+        local backup="$BACKUP_DIR/$(basename "$f")"
+        if [[ -f "$backup" ]]; then
+            cp -a "$backup" "$f"
+        fi
+    done
+    systemctl daemon-reload
+    systemctl start "$SERVICE_NAME" || true
+}
+
+install_from_staging() {
+    local staging="$1"
+    # Required files: remsound-relay.py + remsound-relay.service.
+    if [[ ! -f "$staging/remsound-relay.py" ]]; then
+        log "ERROR: staging missing remsound-relay.py"
+        return 1
+    fi
+    install -o root -g root -m 755 "$staging/remsound-relay.py" "$INSTALL_BIN"
+    python3 -m py_compile "$INSTALL_BIN"
+    if [[ -f "$staging/remsound-relay.service" ]]; then
+        install -o root -g root -m 644 "$staging/remsound-relay.service" "$INSTALL_SERVICE"
+    fi
+    if [[ -f "$staging/remsound-relay-update.sh" ]]; then
+        install -o root -g root -m 755 "$staging/remsound-relay-update.sh" "$INSTALL_UPDATER"
+    fi
+    if [[ -f "$staging/remsound-relay-update.service" ]]; then
+        install -o root -g root -m 644 "$staging/remsound-relay-update.service" "$INSTALL_UPDATE_SERVICE"
+    fi
+    if [[ -f "$staging/remsound-relay-update.timer" ]]; then
+        install -o root -g root -m 644 "$staging/remsound-relay-update.timer" "$INSTALL_UPDATE_TIMER"
+    fi
+    return 0
+}
+
+# -------- main flow ----------------------------------------------------------
+
+main() {
+    require_root
+    ensure_dirs
+
+    log "update check starting (repo=$REPO prefix=$TAG_PREFIX)"
+
+    local current latest_tag asset_url asset_name
+    current="$(read_current_version)"
+    log "currently installed: $current"
+
+    local release_info
+    if ! release_info="$(get_latest_release)"; then
+        log "no upgrade attempted (could not query releases or no eligible release)"
+        return 0
+    fi
+    latest_tag="$(printf '%s\n' "$release_info" | sed -n '1p')"
+    asset_url="$(printf '%s\n' "$release_info" | sed -n '2p')"
+    asset_name="$(printf '%s\n' "$release_info" | sed -n '3p')"
+    log "latest available: $latest_tag asset=$asset_name"
+
+    if ! tag_newer_than "$latest_tag" "$current"; then
+        log "up to date (installed $current >= available $latest_tag)"
+        return 0
+    fi
+
+    log "newer release found: $latest_tag -> upgrading from $current"
+
+    # Working area in /tmp. Use the script-global $WORK_DIR (not a function
+    # local) so the EXIT trap can still see the variable after main returns.
+    # The trap is also script-global, registered just below.
+    WORK_DIR="$(mktemp -d -t remsound-relay-update.XXXXXXXX)"
+
+    local tarball="$WORK_DIR/$asset_name"
+    log "downloading $asset_url"
+    if ! curl --fail --silent --show-error --max-time 120 \
+            --location -o "$tarball" "$asset_url"; then
+        log "ERROR: download failed"
+        return 1
+    fi
+
+    log "extracting $asset_name"
+    if ! tar -xzf "$tarball" -C "$WORK_DIR"; then
+        log "ERROR: tarball extraction failed"
+        return 1
+    fi
+    # Find the staging root — first directory inside the work dir.
+    local staging
+    staging="$(find "$WORK_DIR" -mindepth 1 -maxdepth 1 -type d | head -n 1)"
+    if [[ -z "$staging" ]]; then
+        log "ERROR: tarball did not contain a top-level folder"
+        return 1
+    fi
+    log "staging at $staging"
+
+    snapshot_backup
+
+    log "stopping $SERVICE_NAME"
+    systemctl stop "$SERVICE_NAME" || true
+
+    if ! install_from_staging "$staging"; then
+        log "ERROR: install step failed — rolling back"
+        restore_backup
+        return 1
+    fi
+
+    # Persist the new version BEFORE starting, so a crash after start still
+    # leaves the version file consistent with what's on disk.
+    printf '%s\n' "$latest_tag" > "$VERSION_FILE"
+
+    log "reloading systemd + starting $SERVICE_NAME"
+    systemctl daemon-reload
+    systemctl start "$SERVICE_NAME" || true
+
+    sleep "$HEALTH_WAIT_SECONDS"
+
+    if systemctl is-active --quiet "$SERVICE_NAME"; then
+        log "post-install check: $SERVICE_NAME is active — upgrade to $latest_tag complete"
+        return 0
+    fi
+
+    log "post-install check FAILED: $SERVICE_NAME not active — rolling back"
+    restore_backup
+    if systemctl is-active --quiet "$SERVICE_NAME"; then
+        log "rollback succeeded — back on $current"
+    else
+        log "ERROR: rollback also did not restore service — manual intervention required"
+    fi
+    return 1
+}
+
+main "$@"