From 9e62355271fa39e67b06f00f5601cdb848c7894e Mon Sep 17 00:00:00 2001
From: Eugenio Lacuesta <eugenio.lacuesta@gmail.com>
Date: Tue, 2 Mar 2021 12:09:10 -0300
Subject: [PATCH] Allow logger/stats customization in get_retry_request

---
 scrapy/downloadermiddlewares/retry.py    | 16 ++++++---
 tests/test_downloadermiddleware_retry.py | 44 ++++++++++++++++++++----
 2 files changed, 50 insertions(+), 10 deletions(-)

diff --git a/scrapy/downloadermiddlewares/retry.py b/scrapy/downloadermiddlewares/retry.py
index 0f24e5d28..8955c7e4f 100644
--- a/scrapy/downloadermiddlewares/retry.py
+++ b/scrapy/downloadermiddlewares/retry.py
@@ -29,7 +29,8 @@ from scrapy.utils.response import response_status_message
 from scrapy.core.downloader.handlers.http11 import TunnelError
 from scrapy.utils.python import global_object_name
 
-logger = logging.getLogger(__name__)
+
+retry_logger = logging.getLogger(__name__)
 
 
 def get_retry_request(
@@ -39,6 +40,8 @@ def get_retry_request(
     reason='unspecified',
     max_retry_times=None,
     priority_adjust=None,
+    logger=retry_logger,
+    stats_base_key='retry',
 ):
     """
     Returns a new :class:`~scrapy.Request` object to retry the specified
@@ -76,6 +79,11 @@ def get_retry_request(
     *priority_adjust* is a number that determines how the priority of the new
     request changes in relation to *request*. If not specified, the number is
     read from the :setting:`RETRY_PRIORITY_ADJUST` setting.
+
+    *logger* is the logging.Logger object to be used when logging messages
+
+    *stats_base_key* is a string to be used as the base key for the
+    retry-related job stats
     """
     settings = spider.crawler.settings
     stats = spider.crawler.stats
@@ -102,11 +110,11 @@ def get_retry_request(
         if isinstance(reason, Exception):
             reason = global_object_name(reason.__class__)
 
-        stats.inc_value('retry/count')
-        stats.inc_value(f'retry/reason_count/{reason}')
+        stats.inc_value(f'{stats_base_key}/count')
+        stats.inc_value(f'{stats_base_key}/reason_count/{reason}')
         return new_request
     else:
-        stats.inc_value('retry/max_reached')
+        stats.inc_value(f'{stats_base_key}/max_reached')
         logger.error(
             "Gave up retrying %(request)s (failed %(retry_times)d times): "
             "%(reason)s",
diff --git a/tests/test_downloadermiddleware_retry.py b/tests/test_downloadermiddleware_retry.py
index 46e525f99..915bd3a3e 100644
--- a/tests/test_downloadermiddleware_retry.py
+++ b/tests/test_downloadermiddleware_retry.py
@@ -1,4 +1,7 @@
+import logging
 import unittest
+
+from testfixtures import LogCapture
 from twisted.internet import defer
 from twisted.internet.error import (
     ConnectError,
@@ -9,17 +12,12 @@ from twisted.internet.error import (
 )
 from twisted.web.client import ResponseFailed
 
-from scrapy.downloadermiddlewares.retry import (
-    get_retry_request,
-    RetryMiddleware,
-)
+from scrapy.downloadermiddlewares.retry import get_retry_request, RetryMiddleware
 from scrapy.exceptions import IgnoreRequest
 from scrapy.http import Request, Response
 from scrapy.spiders import Spider
 from scrapy.utils.test import get_crawler
 
-from testfixtures import LogCapture
-
 
 class RetryTest(unittest.TestCase):
     def setUp(self):
@@ -597,6 +595,40 @@ class GetRetryRequestTest(unittest.TestCase):
             )
         )
 
+    def test_custom_logger(self):
+        logger = logging.getLogger("custom-logger")
+        request = Request("https://example.com")
+        spider = self.get_spider()
+        expected_reason = "because"
+        with LogCapture() as log:
+            get_retry_request(
+                request,
+                spider=spider,
+                reason=expected_reason,
+                logger=logger,
+            )
+        log.check_present(
+            (
+                "custom-logger",
+                "DEBUG",
+                f"Retrying {request} (failed 1 times): {expected_reason}",
+            )
+        )
+
+    def test_custom_stats_key(self):
+        request = Request("https://example.com")
+        spider = self.get_spider()
+        expected_reason = "because"
+        stats_key = "custom_retry"
+        get_retry_request(
+            request,
+            spider=spider,
+            reason=expected_reason,
+            stats_base_key=stats_key,
+        )
+        for stat in (f"{stats_key}/count", f"{stats_key}/reason_count/{expected_reason}"):
+            self.assertEqual(spider.crawler.stats.get_value(stat), 1)
+
 
 if __name__ == "__main__":
     unittest.main()