Fetching - Make an obvious error when using BrowserSteps with the simple text fetcher (#2145)

changedetectionio/content_fetcher.py

@@ -61,6 +61,10 @@ class PageUnloadable(Exception):
         self.message = message
         return
 
+class BrowserStepsInUnsupportedFetcher(Exception):
+    def __init__(self, url):
+        self.url = url
+        return
 
 class EmptyReply(Exception):
     def __init__(self, status_code, url, screenshot=None):
@@ -712,6 +716,9 @@ class html_requests(Fetcher):
             current_include_filters=None,
             is_binary=False):
 
+        if self.browser_steps_get_valid_steps():
+            raise BrowserStepsInUnsupportedFetcher(url=url)
+
         # Make requests use a more modern looking user-agent
         if not {k.lower(): v for k, v in request_headers.items()}.get('user-agent', None):
             request_headers['User-Agent'] = os.getenv("DEFAULT_SETTINGS_HEADERS_USERAGENT",

changedetectionio/update_worker.py

@@ -430,6 +430,12 @@ class update_worker(threading.Thread):
                                                                            'last_check_status': e.status_code,
                                                                            'has_ldjson_price_data': None})
                         process_changedetection_results = False
+                    except content_fetcher.BrowserStepsInUnsupportedFetcher as e:
+                        err_text = "This watch has Browser Steps configured and so it cannot run with the 'Basic fast Plaintext/HTTP Client', either remove the Browser Steps or select a Chrome fetcher."
+                        self.datastore.update_watch(uuid=uuid, update_obj={'last_error': err_text})
+                        process_changedetection_results = False
+                        logger.error(f"Exception (BrowserStepsInUnsupportedFetcher) reached processing watch UUID: {uuid}")
+
                     except UnableToExtractRestockData as e:
                         # Usually when fetcher.instock_data returns empty
                         logger.error(f"Exception (UnableToExtractRestockData) reached processing watch UUID: {uuid}")