improve monitor validation message for syntax error

Author: GabrielSalla

src/components/http_server/monitor_routes.py

@@ -190,6 +190,9 @@ async def monitor_validate(request: Request) -> Response:
             "error": e.get_error_message(include_monitor_name=False),
         }
         return web.json_response(error_response, status=400)
+    except SyntaxError as e:
+        error_response = {"status": "error", "error": f"'{e.args[1][3]}' {e.msg}"}
+        return web.json_response(error_response, status=400)
     except Exception as e:
         error_response = {"status": "error", "error": str(e)}
         _logger.error(traceback.format_exc().strip())

tests/components/http_server/test_monitor_routes.py

@@ -381,22 +381,32 @@ async def test_monitor_validate_check_fail():
             }
 
 
+async def test_monitor_validate_syntax_error(mocker):
+    """The 'monitor validate' route should return an error if the provided module code has any
+    errors"""
+    request_payload = {
+        "monitor_code": "print('a",
+    }
+
+    url = BASE_URL + "/validate"
+    async with aiohttp.ClientSession() as session:
+        async with session.post(url, json=request_payload) as response:
+            assert await response.json() == {
+                "status": "error",
+                "error": "'print('a' unterminated string literal (detected at line 1)",
+            }
+
+
 @pytest.mark.parametrize(
     "monitor_code, expected_error",
     [
         ("something", "name 'something' is not defined"),
         ("import time;\n\ntime.abc()", "module 'time' has no attribute 'abc'"),
-        (
-            "print('a",
-            "unterminated string literal (detected at line 1) ({monitor_name}.py, line 1)",
-        ),
     ],
 )
 async def test_monitor_validate_invalid_monitor_code(mocker, monitor_code, expected_error):
     """The 'monitor validate' route should return an error if the provided module code has any
     errors"""
-    check_monitor_spy: MagicMock = mocker.spy(monitors_loader, "check_monitor")
-
     request_payload = {
         "monitor_code": monitor_code,
     }
@@ -406,7 +416,7 @@ async def test_monitor_validate_invalid_monitor_code(mocker, monitor_code, expec
         async with session.post(url, json=request_payload) as response:
             assert await response.json() == {
                 "status": "error",
-                "error": expected_error.format(monitor_name=check_monitor_spy.call_args.args[0]),
+                "error": expected_error,
             }