ntfy-alerts: init

modules/age-secrets.nix

@@ -65,5 +65,20 @@
       owner = "root";
       group = "root";
     };
+
+    # ntfy-alerts secrets
+    ntfy-alerts-topic = {
+      file = ../secrets/ntfy-alerts-topic.age;
+      mode = "0400";
+      owner = "root";
+      group = "root";
+    };
+
+    ntfy-alerts-token = {
+      file = ../secrets/ntfy-alerts-token.age;
+      mode = "0400";
+      owner = "root";
+      group = "root";
+    };
   };
 }

modules/ntfy-alerts.nix

@@ -0,0 +1,121 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfg = config.services.ntfyAlerts;
+
+  curl = "${pkgs.curl}/bin/curl";
+  hostname = config.networking.hostName;
+
+  # Build the curl auth args as a proper bash array fragment
+  authCurlArgs =
+    if cfg.tokenFile != null then
+      ''
+        if [ -f "${cfg.tokenFile}" ]; then
+          TOKEN=$(cat "${cfg.tokenFile}" 2>/dev/null || echo "")
+          if [ -n "$TOKEN" ]; then
+            AUTH_ARGS=(-H "Authorization: Bearer $TOKEN")
+          fi
+        fi
+      ''
+    else
+      "";
+
+  # Systemd failure alert script
+  systemdAlertScript = pkgs.writeShellScript "ntfy-systemd-alert" ''
+    set -euo pipefail
+
+    UNIT_NAME="$1"
+    SERVER_URL="${cfg.serverUrl}"
+    TOPIC=$(cat "${cfg.topicFile}" 2>/dev/null | tr -d '[:space:]')
+    if [ -z "$TOPIC" ]; then
+      echo "ERROR: Could not read topic from ${cfg.topicFile}"
+      exit 1
+    fi
+
+    # Get journal output for context
+    JOURNAL_OUTPUT=$(${pkgs.systemd}/bin/journalctl -u "$UNIT_NAME" -n 15 --no-pager 2>/dev/null || echo "No journal output available")
+
+    # Build auth args
+    AUTH_ARGS=()
+    ${authCurlArgs}
+
+    # Send notification
+    ${curl} -sf --max-time 15 -X POST \
+      "$SERVER_URL/$TOPIC" \
+      -H "Title: [${hostname}] Service failed: $UNIT_NAME" \
+      -H "Priority: high" \
+      -H "Tags: warning" \
+      "''${AUTH_ARGS[@]}" \
+      -d "$JOURNAL_OUTPUT" || true
+  '';
+
+in
+{
+  options.services.ntfyAlerts = {
+    enable = lib.mkEnableOption "ntfy push notifications for system alerts";
+
+    serverUrl = lib.mkOption {
+      type = lib.types.str;
+      description = "The ntfy server URL (e.g. https://ntfy.example.com)";
+      example = "https://ntfy.example.com";
+    };
+
+    topicFile = lib.mkOption {
+      type = lib.types.path;
+      description = "Path to a file containing the ntfy topic name to publish alerts to.";
+      example = "/run/agenix/ntfy-alerts-topic";
+    };
+
+    tokenFile = lib.mkOption {
+      type = lib.types.nullOr lib.types.path;
+      default = null;
+      description = ''
+        Path to a file containing the ntfy auth token.
+        If set, uses Authorization: Bearer header for authentication.
+      '';
+      example = "/run/secrets/ntfy-token";
+    };
+
+  };
+
+  config = lib.mkIf cfg.enable {
+    # Per-service OnFailure for monitored services
+    systemd.services = {
+      "ntfy-alert@" = {
+        description = "Send ntfy notification for failed service %i";
+
+        unitConfig.OnFailure = lib.mkForce "";
+
+        serviceConfig = {
+          Type = "oneshot";
+          ExecStart = "${systemdAlertScript} %i";
+          TimeoutSec = 30;
+        };
+      };
+
+    };
+
+    # Global OnFailure drop-in for all services
+    systemd.packages = [
+      (pkgs.writeTextDir "etc/systemd/system/service.d/onfailure.conf" ''
+        [Unit]
+        OnFailure=ntfy-alert@%p.service
+      '')
+    ];
+    # ZED (ZFS Event Daemon) ntfy notification settings
+    services.zfs.zed = {
+      enableMail = false;
+      settings = {
+        ZED_NTFY_URL = cfg.serverUrl;
+        ZED_NTFY_TOPIC = "$(cat ${cfg.topicFile} | tr -d '[:space:]')";
+        ZED_NTFY_ACCESS_TOKEN = lib.mkIf (cfg.tokenFile != null) "$(cat ${cfg.tokenFile})";
+        ZED_NOTIFY_VERBOSE = true;
+      };
+    };
+
+  };
+}