mqtt as optional extra

pyproject.toml

@@ -27,7 +27,6 @@ dependencies = [
     "PyYAML>=6.0.1,<7",
     "jmespath>=1,<2",
     "jsonschema>=4,<5",
-    "paho-mqtt>=1.3.1,<=1.6.1",
     "pyjwt>=2.5.0,<3",
     "pykwalify>=1.8.0,<2",
     "pytest>=7,<7.3",
@@ -89,6 +88,9 @@ dev = [
     # "tbump@https://github.com/michaelboulton/tbump/archive/714ba8957a3c84b625608ceca39811ebe56229dc.zip",
 ]
 
+mqtt = [
+    "paho-mqtt>=1.3.1,<=1.6.1",
+]
 
 [project.scripts]
 

tavern/_core/plugins.py

@@ -4,6 +4,7 @@
 significantly if/when a proper plugin system is implemented!
 """
 import dataclasses
+import importlib.util
 import logging
 from functools import partial
 from typing import Any, List, Mapping, Optional
@@ -105,7 +106,12 @@ def enabled(current_backend, ext):
                 ext.name == test_block_config.tavern_internal.backends[current_backend]
             )
 
-        for backend in ["http", "mqtt"]:
+        backends = ["http"]
+
+        if importlib.util.find_spec("paho.mqtt") is not None:
+            backends.append("mqtt")
+
+        for backend in backends:
             namespace = "tavern_{}".format(backend)
 
             manager = stevedore.EnabledExtensionManager(

tests/conftest.py

@@ -6,7 +6,8 @@
 import yaml
 
 import tavern
-import tavern._plugins.mqtt.tavernhook as mqtt_plugin
+
+# import tavern._plugins.mqtt.tavernhook as mqtt_plugin
 from tavern._plugins.rest.tavernhook import TavernRestPlugin as rest_plugin
 
 
@@ -28,8 +29,8 @@ def extension(name, point):
             "requests",
             rest_plugin,
         ),
-        extension(
-            "paho-mqtt",
-            mqtt_plugin,
-        ),
+        # extension(
+        #     "paho-mqtt",
+        #     mqtt_plugin,
+        # ),
     ]

tox-integration.ini

@@ -6,6 +6,8 @@ isolated_build = True
 [testenv]
 allowlist_externals =
     docker
+extras =
+    mqtt: mqtt
 basepython = python3.11
 passenv = DOCKER_TLS_VERIFY,DOCKER_HOST,DOCKER_CERT_PATH,DOCKER_BUILDKIT
 setenv =

tox.ini

@@ -11,6 +11,7 @@ allowlist_externals =
 install_command = python -m pip install {opts} {packages} -c constraints.txt
 extras =
     dev
+    mqtt
 commands =
     {envbindir}/python -m pytest --cov-report term-missing --cov tavern {posargs}