Added publishversion to core and documentation

Author: psyciknz

HANDBOOK.md

@@ -132,6 +132,9 @@ I've written an introductory post, explaining [what mqttwarn can be used for](ht
   ; name the service providers you will be using.
   launch   = file, log, osxnotify, mysql, smtp
 
+  ; Publish the current mqttwarn version to the topic (retained)
+  publishversion = mqttwarn/version
+
 
   ; optional: TLS parameters. (Don't forget to set the port number for
   ; TLS (probably 8883).
@@ -164,6 +167,18 @@ I've written an introductory post, explaining [what mqttwarn can be used for](ht
   
   You should launch every service you want to use from your topic/target definitions here.
   
+  ###### `publishversion`
+
+  A topic that, when it exists, mqttwarn will publish it's current version as a retained payload.
+  Useful for automated updates (docker watchtower and the like)
+
+  For example:
+  ```
+  root@mymachine:~$  mosquitto_sub -v -t mqttwarn/version
+  mqttwarn/version 0.25.0
+  ```
+
+
   #### The `[config:xxx]` sections
 
   Sections called `[config:xxx]` configure settings for a service _xxx_. Each of these sections

mqttwarn/core.py

@@ -20,6 +20,7 @@
 
 import paho.mqtt.client as paho
 
+from mqttwarn import __version__
 from mqttwarn.context import RuntimeContext, FunctionInvoker
 from mqttwarn.cron import PeriodicThread
 from mqttwarn.util import \
@@ -628,6 +629,12 @@ def connect():
     # Update our runtime context (used by functions etc) now we have a connected MQTT client
     context.invoker.srv.mqttc = mqttc
 
+    try:
+        if cf.publishversion:
+            mqttc.publish(cf.publishversion,__version__,retain=True)
+    except: 
+        pass
+
     # Launch worker threads to operate on queue
     start_workers()
 

mqttwarn/examples/basic/mqttwarn.ini

@@ -55,6 +55,10 @@ functions = 'samplefuncs.py'
 ; name the service providers you will be using.
 launch    = file, log
 
+; Publish the current mqttwarn version to the topic (retained)
+publishversion = mqttwarn/version
+
+
 
 ; -------
 ; Targets

tests/test_core.py

@@ -16,6 +16,8 @@
     configfile_service_loading,
     configfile_unknown_functions,
 )
+
+
 from tests.util import core_bootstrap, send_message
 
 
@@ -282,3 +284,31 @@ def test_config_bad_functions(caplog):
         error_message = str(excinfo.value)
         assert "UNKNOWN FILE REFERENCE" in error_message
         assert "not found" in error_message
+
+
+def inactive_test_status_publish(caplog):
+    """
+    Aim to test the `status_publish` feature.
+    Test the core connection method.
+
+    Note:
+        We need figure out how ot mock a connection to a non-existent MQTT server.
+    """
+
+    from unittest import mock
+    from unittest.mock import call, PropertyMock
+    from mqttwarn.core import connect
+
+    with caplog.at_level(logging.DEBUG):
+
+        # Bootstrap the core machinery without MQTT
+        core_bootstrap(configfile=configfile_full)
+
+        mqtt_publish_mock = mock.MagicMock()
+        mqttc = mqtt_publish_mock
+
+        # Signal mocked MQTT message to the core machinery for processing
+        outcome = connect().mqttc = mqtt_publish_mock
+
+        # Proof that the message has been routed to the "log" plugin properly
+        #assert assertion here to verify the connection