add warning

Author: Mantisus

src/crawlee/crawlers/_abstract_http/_abstract_http_crawler.py

@@ -2,6 +2,7 @@
 
 import asyncio
 import logging
+import warnings
 from abc import ABC
 from datetime import timedelta
 from typing import TYPE_CHECKING, Generic
@@ -47,6 +48,12 @@ class HttpCrawlerOptions(
     navigation_timeout: NotRequired[timedelta | None]
     """Timeout for the HTTP request."""
 
+    impersonate: NotRequired[bool]
+    """Whether the default HTTP client should impersonate a browser by sending browser-like headers. This applies only
+        to the default client. If you pass your own `http_client`, this flag is ignored and you configure impersonation
+        on that client directly.
+    """
+
 
 @docs_group('Crawlers')
 class AbstractHttpCrawler(
@@ -101,6 +108,15 @@ def __init__(
 
         if impersonate is False and 'http_client' not in kwargs:
             kwargs['http_client'] = ImpitHttpClient(browser=None)
+        elif impersonate is False and 'http_client' in kwargs:
+            warnings.warn(
+                (
+                    '`impersonate` option is ignored when custom `http_client` is provided. '
+                    'Please configure impersonation directly on the `http_client` instance.'
+                ),
+                category=UserWarning,
+                stacklevel=2,
+            )
 
         kwargs.setdefault('_logger', logging.getLogger(self.__class__.__name__))
         super().__init__(**kwargs)