From b9cc32d8a1ba845be330a3fa6b39188b19569ec6 Mon Sep 17 00:00:00 2001
From: Andreas Motl <andreas@hiveeyes.org>
Date: Sun, 21 Apr 2024 22:29:46 +0200
Subject: [PATCH] Data Model: Make MQTT settings optional

To allow running the data logger without configuring them.
---
 CHANGES.md                  | 2 ++
 ds18b20_datalogger/model.py | 9 ++++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/CHANGES.md b/CHANGES.md
index 6845bf7..ecd343f 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -5,6 +5,8 @@
   `version`. Thanks, @bee-mois.
 - Emit user admonition on `make-config` subcommand. Thanks,
   @bee-mois.
+- Data Model: Make MQTT settings optional, to allow running the
+  data logger without configuring them.
 
 ## v0.0.3 - 2024-04-20
 - Tests: Make sensor tests work, using a fake sysfs filesystem
diff --git a/ds18b20_datalogger/model.py b/ds18b20_datalogger/model.py
index db5f4a5..f3e89a1 100644
--- a/ds18b20_datalogger/model.py
+++ b/ds18b20_datalogger/model.py
@@ -66,8 +66,8 @@ class Settings:
     General settings container.
     """
 
-    mqtt: MqttSettings
-    devicemap: DeviceMap
+    mqtt: t.Union[MqttSettings, None]
+    devicemap: t.Union[DeviceMap, None]
 
     @classmethod
     def from_file(cls, configfile: Path):
@@ -75,7 +75,10 @@ def from_file(cls, configfile: Path):
         devicemap = DeviceMap()
         for item in data["one-wire"]:
             devicemap.devices.append(Device(**item))
-        return cls(mqtt=MqttSettings(**data["mqtt"]), devicemap=devicemap)
+        mqtt = None
+        if "mqtt" in data:
+            mqtt = MqttSettings(**data["mqtt"])
+        return cls(mqtt=mqtt, devicemap=devicemap)
 
 
 @dataclasses.dataclass