From 4c181bbfe5f4f62dbd467c589c010ebecd844bd4 Mon Sep 17 00:00:00 2001
From: Paulus Schoutsen <balloob@gmail.com>
Date: Fri, 5 Mar 2021 15:34:18 -0800
Subject: [PATCH] Raise error instead of crashing when template passed to call
 service target (#47467)

---
 .../components/websocket_api/commands.py      | 16 +++++---
 .../components/websocket_api/test_commands.py | 40 +++++++++++--------
 2 files changed, 34 insertions(+), 22 deletions(-)

diff --git a/homeassistant/components/websocket_api/commands.py b/homeassistant/components/websocket_api/commands.py
index ddd7548cd68..53531cf9ba9 100644
--- a/homeassistant/components/websocket_api/commands.py
+++ b/homeassistant/components/websocket_api/commands.py
@@ -13,10 +13,9 @@ from homeassistant.exceptions import (
     TemplateError,
     Unauthorized,
 )
-from homeassistant.helpers import config_validation as cv, entity
+from homeassistant.helpers import config_validation as cv, entity, template
 from homeassistant.helpers.event import TrackTemplate, async_track_template_result
 from homeassistant.helpers.service import async_get_all_descriptions
-from homeassistant.helpers.template import Template
 from homeassistant.loader import IntegrationNotFound, async_get_integration
 
 from . import const, decorators, messages
@@ -132,6 +131,11 @@ async def handle_call_service(hass, connection, msg):
     if msg["domain"] == HASS_DOMAIN and msg["service"] in ["restart", "stop"]:
         blocking = False
 
+    # We do not support templates.
+    target = msg.get("target")
+    if template.is_complex(target):
+        raise vol.Invalid("Templates are not supported here")
+
     try:
         context = connection.context(msg)
         await hass.services.async_call(
@@ -140,7 +144,7 @@ async def handle_call_service(hass, connection, msg):
             msg.get("service_data"),
             blocking,
             context,
-            target=msg.get("target"),
+            target=target,
         )
         connection.send_message(
             messages.result_message(msg["id"], {"context": context})
@@ -256,14 +260,14 @@ def handle_ping(hass, connection, msg):
 async def handle_render_template(hass, connection, msg):
     """Handle render_template command."""
     template_str = msg["template"]
-    template = Template(template_str, hass)
+    template_obj = template.Template(template_str, hass)
     variables = msg.get("variables")
     timeout = msg.get("timeout")
     info = None
 
     if timeout:
         try:
-            timed_out = await template.async_render_will_timeout(timeout)
+            timed_out = await template_obj.async_render_will_timeout(timeout)
         except TemplateError as ex:
             connection.send_error(msg["id"], const.ERR_TEMPLATE_ERROR, str(ex))
             return
@@ -294,7 +298,7 @@ async def handle_render_template(hass, connection, msg):
     try:
         info = async_track_template_result(
             hass,
-            [TrackTemplate(template, variables)],
+            [TrackTemplate(template_obj, variables)],
             _template_listener,
             raise_on_template_error=True,
         )
diff --git a/tests/components/websocket_api/test_commands.py b/tests/components/websocket_api/test_commands.py
index 1f7abc42c4e..f596db63c5e 100644
--- a/tests/components/websocket_api/test_commands.py
+++ b/tests/components/websocket_api/test_commands.py
@@ -21,13 +21,7 @@ from tests.common import MockEntity, MockEntityPlatform, async_mock_service
 
 async def test_call_service(hass, websocket_client):
     """Test call service command."""
-    calls = []
-
-    @callback
-    def service_call(call):
-        calls.append(call)
-
-    hass.services.async_register("domain_test", "test_service", service_call)
+    calls = async_mock_service(hass, "domain_test", "test_service")
 
     await websocket_client.send_json(
         {
@@ -54,13 +48,7 @@ async def test_call_service(hass, websocket_client):
 
 async def test_call_service_target(hass, websocket_client):
     """Test call service command with target."""
-    calls = []
-
-    @callback
-    def service_call(call):
-        calls.append(call)
-
-    hass.services.async_register("domain_test", "test_service", service_call)
+    calls = async_mock_service(hass, "domain_test", "test_service")
 
     await websocket_client.send_json(
         {
@@ -93,6 +81,28 @@ async def test_call_service_target(hass, websocket_client):
     }
 
 
+async def test_call_service_target_template(hass, websocket_client):
+    """Test call service command with target does not allow template."""
+    await websocket_client.send_json(
+        {
+            "id": 5,
+            "type": "call_service",
+            "domain": "domain_test",
+            "service": "test_service",
+            "service_data": {"hello": "world"},
+            "target": {
+                "entity_id": "{{ 1 }}",
+            },
+        }
+    )
+
+    msg = await websocket_client.receive_json()
+    assert msg["id"] == 5
+    assert msg["type"] == const.TYPE_RESULT
+    assert not msg["success"]
+    assert msg["error"]["code"] == const.ERR_INVALID_FORMAT
+
+
 async def test_call_service_not_found(hass, websocket_client):
     """Test call service command."""
     await websocket_client.send_json(
@@ -232,7 +242,6 @@ async def test_call_service_error(hass, websocket_client):
     )
 
     msg = await websocket_client.receive_json()
-    print(msg)
     assert msg["id"] == 5
     assert msg["type"] == const.TYPE_RESULT
     assert msg["success"] is False
@@ -249,7 +258,6 @@ async def test_call_service_error(hass, websocket_client):
     )
 
     msg = await websocket_client.receive_json()
-    print(msg)
     assert msg["id"] == 6
     assert msg["type"] == const.TYPE_RESULT
     assert msg["success"] is False