Explain rejected notifications.

And run as a dynamic user.

module.nix

@@ -50,6 +50,8 @@ in {
       path = [ tattler ];
       wantedBy = [ "default.target" ];
       serviceConfig = {
+        DynamicUser = true;
+        LoadCredential = [ "mqtt.passwd:${cfg.mqtt.password-file}" ];
         ExecStart = pkgs.writeShellScript "tattler.sh" (concatStringsSep " " ([
           "tattler"
           "--mqtt-host=${cfg.mqtt.host}"
@@ -59,7 +61,8 @@ in {
         ] ++ (optional cfg.verbose "--verbose")
           ++ (optional (cfg.mqtt.user != null) "--mqtt-user=${cfg.mqtt.user}")
           ++ (optional (cfg.mqtt.password-file != null)
-            "--mqtt-user=${cfg.mqtt.password-file}")));
+            "--mqtt-user=$CREDENTIALS_DIRECTORY/mqtt.passwd")));
+        Restart = "always";
       };
     };
   };

src/tattler/core.clj

@@ -26,6 +26,7 @@
                                           :body    (:body note)
                                           :urgency (-> note :urgency (keyword))
                                           })
-              (log/error! logger (format "rejecting invalid notification: %s" note)))
+              (log/error! logger (format "rejecting invalid notification: %s"
+                                         (->> note (t/explain Notification) (t/humanize)))))
             (recur (<! note-chan)))
         (log/info! logger "stopping")))))