Add additional startup checks

install/production-filesystem/services/scripts/check-nginx-config.sh

@@ -0,0 +1,50 @@
+#!/bin/sh
+# check-nginx-config.sh - verify nginx conf.active mount is writable when startup needs to render config.
+
+CONF_ACTIVE_DIR="${SYSTEM_NGINX_CONFIG}/conf.active"
+TARGET_FILE="${CONF_ACTIVE_DIR}/netalertx.conf"
+
+# If the directory is missing entirely we warn and exit failure so the caller can see the message.
+if [ ! -d "${CONF_ACTIVE_DIR}" ]; then
+    YELLOW=$(printf '\033[1;33m')
+    RESET=$(printf '\033[0m')
+    >&2 printf "%s" "${YELLOW}"
+    >&2 cat <<EOF
+══════════════════════════════════════════════════════════════════════════════
+⚠️  ATTENTION: Nginx configuration mount ${CONF_ACTIVE_DIR} is missing.
+
+    Custom listen address or port changes require a writable nginx conf.active
+    directory. Without it, the container falls back to defaults and ignores
+    your overrides.
+
+    Create a bind mount:
+        --mount type=bind,src=/path/on/host,dst=${CONF_ACTIVE_DIR}
+    and ensure it is owned by the netalertx user (20211:20211) with 700 perms.
+══════════════════════════════════════════════════════════════════════════════
+EOF
+    >&2 printf "%s" "${RESET}"
+    exit 1
+fi
+
+TMP_FILE="${CONF_ACTIVE_DIR}/.netalertx-write-test"
+if ! ( : >"${TMP_FILE}" ) 2>/dev/null; then
+    YELLOW=$(printf '\033[1;33m')
+    RESET=$(printf '\033[0m')
+    >&2 printf "%s" "${YELLOW}"
+    >&2 cat <<EOF
+══════════════════════════════════════════════════════════════════════════════
+⚠️  ATTENTION: Unable to write to ${TARGET_FILE}.
+
+    Ensure the conf.active mount is writable by the netalertx user before
+    changing LISTEN_ADDR or PORT. Fix permissions:
+        chown -R 20211:20211 ${CONF_ACTIVE_DIR}
+        find ${CONF_ACTIVE_DIR} -type d -exec chmod 700 {} +
+        find ${CONF_ACTIVE_DIR} -type f -exec chmod 600 {} +
+══════════════════════════════════════════════════════════════════════════════
+EOF
+    >&2 printf "%s" "${RESET}"
+    exit 1
+fi
+rm -f "${TMP_FILE}"
+
+exit 0