Service validation for MQTT component.

* Service validation for MQTT component.

* Fixes for failing mqtt tests.

- Changed behaviour when both 'payload' and 'payload_template' are provided
  instead of silently ignoring the payload_template value.
- Have validation accept any type of payload and leave encoding to paho-mqtt.

homeassistant/components/mqtt/__init__.py

@@ -9,12 +9,14 @@ import os
 import socket
 import time
 
+import voluptuous as vol
 
 from homeassistant.bootstrap import prepare_setup_platform
 from homeassistant.config import load_yaml_config_file
 from homeassistant.exceptions import HomeAssistantError
 import homeassistant.util as util
 from homeassistant.helpers import template
+import homeassistant.helpers.config_validation as cv
 from homeassistant.const import (
     EVENT_HOMEASSISTANT_START, EVENT_HOMEASSISTANT_STOP)
 
@@ -57,6 +59,22 @@ ATTR_RETAIN = 'retain'
 MAX_RECONNECT_WAIT = 300  # seconds
 
 
+# Service call validation schema
+def mqtt_topic(value):
+    """Validate that we can publish using this MQTT topic."""
+    if isinstance(value, str) and all(c not in value for c in '#+\0'):
+        return vol.Length(min=1, max=65535)(value)
+    raise vol.Invalid('Invalid MQTT topic name')
+
+MQTT_PUBLISH_SCHEMA = vol.Schema({
+    vol.Required(ATTR_TOPIC): mqtt_topic,
+    vol.Exclusive(ATTR_PAYLOAD, 'payload'): object,
+    vol.Exclusive(ATTR_PAYLOAD_TEMPLATE, 'payload'): cv.string,
+    vol.Required(ATTR_QOS, default=DEFAULT_QOS): vol.In([0, 1, 2]),
+    vol.Required(ATTR_RETAIN, default=DEFAULT_RETAIN): vol.Coerce(bool),
+})
+
+
 def _build_publish_data(topic, qos, retain):
     """Build the arguments for the publish service without the payload."""
     data = {ATTR_TOPIC: topic}
@@ -170,26 +188,18 @@ def setup(hass, config):
 
     def publish_service(call):
         """Handle MQTT publish service calls."""
-        msg_topic = call.data.get(ATTR_TOPIC)
+        msg_topic = call.data[ATTR_TOPIC]
         payload = call.data.get(ATTR_PAYLOAD)
         payload_template = call.data.get(ATTR_PAYLOAD_TEMPLATE)
-        qos = call.data.get(ATTR_QOS, DEFAULT_QOS)
-        retain = call.data.get(ATTR_RETAIN, DEFAULT_RETAIN)
-        if payload is None:
-            if payload_template is None:
-                _LOGGER.error(
-                    "You must set either '%s' or '%s' to use this service",
-                    ATTR_PAYLOAD, ATTR_PAYLOAD_TEMPLATE)
-                return
-            try:
-                payload = template.render(hass, payload_template)
-            except template.jinja2.TemplateError as exc:
-                _LOGGER.error(
-                    "Unable to publish to '%s': rendering payload template of "
-                    "'%s' failed because %s.",
-                    msg_topic, payload_template, exc)
-                return
-        if msg_topic is None or payload is None:
+        qos = call.data[ATTR_QOS]
+        retain = call.data[ATTR_RETAIN]
+        try:
+            payload = payload or template.render(hass, payload_template)
+        except template.jinja2.TemplateError as exc:
+            _LOGGER.error(
+                "Unable to publish to '%s': rendering payload template of "
+                "'%s' failed because %s.",
+                msg_topic, payload_template, exc)
             return
         MQTT_CLIENT.publish(msg_topic, payload, qos, retain)
 
@@ -199,7 +209,8 @@ def setup(hass, config):
         os.path.join(os.path.dirname(__file__), 'services.yaml'))
 
     hass.services.register(DOMAIN, SERVICE_PUBLISH, publish_service,
-                           descriptions.get(SERVICE_PUBLISH))
+                           descriptions.get(SERVICE_PUBLISH),
+                           schema=MQTT_PUBLISH_SCHEMA)
 
     return True
 

tests/components/mqtt/test_init.py

@@ -90,19 +90,16 @@ class TestMQTT(unittest.TestCase):
     def test_service_call_with_payload_doesnt_render_template(self):
         """Test the service call with unrendered template.
 
-        If a 'payload' is provided then use that instead of 'payload_template'.
+        If both 'payload' and 'payload_template' are provided then fail.
         """
         payload = "not a template"
         payload_template = "a template"
-        # Call the service directly because the helper functions don't allow
-        # you to provide payload AND payload_template.
         self.hass.services.call(mqtt.DOMAIN, mqtt.SERVICE_PUBLISH, {
             mqtt.ATTR_TOPIC: "test/topic",
             mqtt.ATTR_PAYLOAD: payload,
             mqtt.ATTR_PAYLOAD_TEMPLATE: payload_template
         }, blocking=True)
-        self.assertTrue(mqtt.MQTT_CLIENT.publish.called)
-        self.assertEqual(mqtt.MQTT_CLIENT.publish.call_args[0][1], payload)
+        self.assertFalse(mqtt.MQTT_CLIENT.publish.called)
 
     def test_service_call_without_payload_or_payload_template(self):
         """Test the service call without payload or payload template.