Add tests for get_retry_request

scrapy/downloadermiddlewares/retry.py

@@ -10,6 +10,7 @@ Failed pages are collected on the scraping process and rescheduled at the end,
 once the spider has finished crawling all regular (non failed) pages.
 """
 import logging
+from inspect import isclass
 
 from twisted.internet import defer
 from twisted.internet.error import (
@@ -81,8 +82,8 @@ def get_retry_request(
     retry_times = request.meta.get('retry_times', 0) + 1
     if max_retry_times is None:
         max_retry_times = request.meta.get('max_retry_times')
-    if max_retry_times is None:
-        max_retry_times = settings.getint('RETRY_TIMES')
+        if max_retry_times is None:
+            max_retry_times = settings.getint('RETRY_TIMES')
     if retry_times <= max_retry_times:
         logger.debug(
             "Retrying %(request)s (failed %(retry_times)d times): %(reason)s",
@@ -96,6 +97,8 @@ def get_retry_request(
             priority_adjust = settings.getint('RETRY_PRIORITY_ADJUST')
         new_request.priority = request.priority + priority_adjust
 
+        if isclass(reason):
+            reason = reason()
         if isinstance(reason, Exception):
             reason = global_object_name(reason.__class__)
 
@@ -149,10 +152,12 @@ class RetryMiddleware:
             return self._retry(request, exception, spider)
 
     def _retry(self, request, reason, spider):
+        max_retry_times = request.meta.get('max_retry_times', self.max_retry_times)
+        priority_adjust = request.meta.get('priority_adjust', self.priority_adjust)
         return get_retry_request(
             request,
             reason=reason,
             spider=spider,
-            max_retry_times=self.max_retry_times,
-            priority_adjust=self.priority_adjust,
+            max_retry_times=max_retry_times,
+            priority_adjust=priority_adjust,
         )

tests/test_downloadermiddleware_retry.py

@@ -4,18 +4,22 @@ from twisted.internet.error import (
     ConnectError,
     ConnectionDone,
     ConnectionLost,
-    ConnectionRefusedError,
     DNSLookupError,
     TCPTimedOutError,
-    TimeoutError,
 )
 from twisted.web.client import ResponseFailed
 
-from scrapy.downloadermiddlewares.retry import RetryMiddleware
-from scrapy.spiders import Spider
+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):
@@ -119,82 +123,480 @@ class RetryTest(unittest.TestCase):
 
 
 class MaxRetryTimesTest(unittest.TestCase):
-    def setUp(self):
-        self.crawler = get_crawler(Spider)
-        self.spider = self.crawler._create_spider('foo')
-        self.mw = RetryMiddleware.from_crawler(self.crawler)
-        self.mw.max_retry_times = 2
-        self.invalid_url = 'http://www.scrapytest.org/invalid_url'
+
+    invalid_url = 'http://www.scrapytest.org/invalid_url'
+
+    def get_spider_and_middleware(self, settings=None):
+        crawler = get_crawler(Spider, settings or {})
+        spider = crawler._create_spider('foo')
+        middleware = RetryMiddleware.from_crawler(crawler)
+        return spider, middleware
 
     def test_with_settings_zero(self):
-
-        # SETTINGS: RETRY_TIMES = 0
-        self.mw.max_retry_times = 0
-
+        max_retry_times = 0
+        settings = {'RETRY_TIMES': max_retry_times}
+        spider, middleware = self.get_spider_and_middleware(settings)
         req = Request(self.invalid_url)
-        self._test_retry(req, DNSLookupError('foo'), self.mw.max_retry_times)
+        self._test_retry(
+            req,
+            DNSLookupError('foo'),
+            max_retry_times,
+            spider=spider,
+            middleware=middleware,
+        )
 
     def test_with_metakey_zero(self):
-
-        # SETTINGS: meta(max_retry_times) = 0
-        meta_max_retry_times = 0
-
-        req = Request(self.invalid_url, meta={'max_retry_times': meta_max_retry_times})
-        self._test_retry(req, DNSLookupError('foo'), meta_max_retry_times)
+        max_retry_times = 0
+        spider, middleware = self.get_spider_and_middleware()
+        meta = {'max_retry_times': max_retry_times}
+        req = Request(self.invalid_url, meta=meta)
+        self._test_retry(
+            req,
+            DNSLookupError('foo'),
+            max_retry_times,
+            spider=spider,
+            middleware=middleware,
+        )
 
     def test_without_metakey(self):
-
-        # SETTINGS: RETRY_TIMES is NON-ZERO
-        self.mw.max_retry_times = 5
-
+        max_retry_times = 5
+        settings = {'RETRY_TIMES': max_retry_times}
+        spider, middleware = self.get_spider_and_middleware(settings)
         req = Request(self.invalid_url)
-        self._test_retry(req, DNSLookupError('foo'), self.mw.max_retry_times)
+        self._test_retry(
+            req,
+            DNSLookupError('foo'),
+            max_retry_times,
+            spider=spider,
+            middleware=middleware,
+        )
 
     def test_with_metakey_greater(self):
-
-        # SETINGS: RETRY_TIMES < meta(max_retry_times)
-        self.mw.max_retry_times = 2
         meta_max_retry_times = 3
+        middleware_max_retry_times = 2
 
         req1 = Request(self.invalid_url, meta={'max_retry_times': meta_max_retry_times})
         req2 = Request(self.invalid_url)
 
-        self._test_retry(req1, DNSLookupError('foo'), meta_max_retry_times)
-        self._test_retry(req2, DNSLookupError('foo'), self.mw.max_retry_times)
+        settings = {'RETRY_TIMES': middleware_max_retry_times}
+        spider, middleware = self.get_spider_and_middleware(settings)
+
+        self._test_retry(
+            req1,
+            DNSLookupError('foo'),
+            meta_max_retry_times,
+            spider=spider,
+            middleware=middleware,
+        )
+        self._test_retry(
+            req2,
+            DNSLookupError('foo'),
+            middleware_max_retry_times,
+            spider=spider,
+            middleware=middleware,
+        )
 
     def test_with_metakey_lesser(self):
-
-        # SETINGS: RETRY_TIMES > meta(max_retry_times)
-        self.mw.max_retry_times = 5
         meta_max_retry_times = 4
+        middleware_max_retry_times = 5
 
         req1 = Request(self.invalid_url, meta={'max_retry_times': meta_max_retry_times})
         req2 = Request(self.invalid_url)
 
-        self._test_retry(req1, DNSLookupError('foo'), meta_max_retry_times)
-        self._test_retry(req2, DNSLookupError('foo'), self.mw.max_retry_times)
+        settings = {'RETRY_TIMES': middleware_max_retry_times}
+        spider, middleware = self.get_spider_and_middleware(settings)
+
+        self._test_retry(
+            req1,
+            DNSLookupError('foo'),
+            meta_max_retry_times,
+            spider=spider,
+            middleware=middleware,
+        )
+        self._test_retry(
+            req2,
+            DNSLookupError('foo'),
+            middleware_max_retry_times,
+            spider=spider,
+            middleware=middleware,
+        )
 
     def test_with_dont_retry(self):
+        max_retry_times = 4
+        spider, middleware = self.get_spider_and_middleware()
+        meta = {
+            'max_retry_times': max_retry_times,
+            'dont_retry': True,
+        }
+        req = Request(self.invalid_url, meta=meta)
+        self._test_retry(
+            req,
+            DNSLookupError('foo'),
+            0,
+            spider=spider,
+            middleware=middleware,
+        )
 
-        # SETTINGS: meta(max_retry_times) = 4
-        meta_max_retry_times = 4
-
-        req = Request(self.invalid_url, meta={
-            'max_retry_times': meta_max_retry_times, 'dont_retry': True
-        })
-
-        self._test_retry(req, DNSLookupError('foo'), 0)
-
-    def _test_retry(self, req, exception, max_retry_times):
+    def _test_retry(
+        self,
+        req,
+        exception,
+        max_retry_times,
+        spider=None,
+        middleware=None,
+    ):
+        spider = spider or self.spider
+        middleware = middleware or self.mw
 
         for i in range(0, max_retry_times):
-            req = self.mw.process_exception(req, exception, self.spider)
+            req = middleware.process_exception(req, exception, spider)
             assert isinstance(req, Request)
 
         # discard it
-        req = self.mw.process_exception(req, exception, self.spider)
+        req = middleware.process_exception(req, exception, spider)
         self.assertEqual(req, None)
 
 
+class GetRetryRequestTest(unittest.TestCase):
+
+    def get_spider(self, settings=None):
+        crawler = get_crawler(Spider, settings or {})
+        return crawler._create_spider('foo')
+
+    def test_basic_usage(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+            )
+        self.assertIsInstance(new_request, Request)
+        self.assertNotEqual(new_request, request)
+        self.assertEqual(new_request.dont_filter, True)
+        expected_retry_times = 1
+        self.assertEqual(new_request.meta['retry_times'], expected_retry_times)
+        self.assertEqual(new_request.priority, -1)
+        expected_reason = "unspecified"
+        for stat in ('retry/count', f'retry/reason_count/{expected_reason}'):
+            self.assertEqual(spider.crawler.stats.get_value(stat), 1)
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "DEBUG",
+                f"Retrying {request} (failed {expected_retry_times} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_max_retries_reached(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        max_retry_times = 0
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                max_retry_times=max_retry_times,
+            )
+        self.assertEqual(new_request, None)
+        self.assertEqual(
+            spider.crawler.stats.get_value('retry/max_reached'),
+            1
+        )
+        failure_count = max_retry_times + 1
+        expected_reason = "unspecified"
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "ERROR",
+                f"Gave up retrying {request} (failed {failure_count} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_one_retry(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                max_retry_times=1,
+            )
+        self.assertIsInstance(new_request, Request)
+        self.assertNotEqual(new_request, request)
+        self.assertEqual(new_request.dont_filter, True)
+        expected_retry_times = 1
+        self.assertEqual(new_request.meta['retry_times'], expected_retry_times)
+        self.assertEqual(new_request.priority, -1)
+        expected_reason = "unspecified"
+        for stat in ('retry/count', f'retry/reason_count/{expected_reason}'):
+            self.assertEqual(spider.crawler.stats.get_value(stat), 1)
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "DEBUG",
+                f"Retrying {request} (failed {expected_retry_times} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_two_retries(self):
+        spider = self.get_spider()
+        request = Request('https://example.com')
+        new_request = request
+        max_retry_times = 2
+        for index in range(max_retry_times):
+            with LogCapture() as log:
+                new_request = get_retry_request(
+                    new_request,
+                    spider=spider,
+                    max_retry_times=max_retry_times,
+                )
+            self.assertIsInstance(new_request, Request)
+            self.assertNotEqual(new_request, request)
+            self.assertEqual(new_request.dont_filter, True)
+            expected_retry_times = index+1
+            self.assertEqual(new_request.meta['retry_times'], expected_retry_times)
+            self.assertEqual(new_request.priority, -expected_retry_times)
+            expected_reason = "unspecified"
+            for stat in ('retry/count', f'retry/reason_count/{expected_reason}'):
+                value = spider.crawler.stats.get_value(stat)
+                self.assertEqual(value, expected_retry_times)
+            log.check_present(
+                (
+                    "scrapy.downloadermiddlewares.retry",
+                    "DEBUG",
+                    f"Retrying {request} (failed {expected_retry_times} times): "
+                    f"{expected_reason}",
+                )
+            )
+
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                new_request,
+                spider=spider,
+                max_retry_times=max_retry_times,
+            )
+        self.assertEqual(new_request, None)
+        self.assertEqual(
+            spider.crawler.stats.get_value('retry/max_reached'),
+            1
+        )
+        failure_count = max_retry_times + 1
+        expected_reason = "unspecified"
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "ERROR",
+                f"Gave up retrying {request} (failed {failure_count} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_no_spider(self):
+        request = Request('https://example.com')
+        with self.assertRaises(TypeError):
+            get_retry_request(request)
+
+    def test_max_retry_times_setting(self):
+        max_retry_times = 0
+        spider = self.get_spider({'RETRY_TIMES': max_retry_times})
+        request = Request('https://example.com')
+        new_request = get_retry_request(
+            request,
+            spider=spider,
+        )
+        self.assertEqual(new_request, None)
+
+    def test_max_retry_times_meta(self):
+        max_retry_times = 0
+        spider = self.get_spider({'RETRY_TIMES': max_retry_times + 1})
+        meta = {'max_retry_times': max_retry_times}
+        request = Request('https://example.com', meta=meta)
+        new_request = get_retry_request(
+            request,
+            spider=spider,
+        )
+        self.assertEqual(new_request, None)
+
+    def test_max_retry_times_argument(self):
+        max_retry_times = 0
+        spider = self.get_spider({'RETRY_TIMES': max_retry_times + 1})
+        meta = {'max_retry_times': max_retry_times + 1}
+        request = Request('https://example.com', meta=meta)
+        new_request = get_retry_request(
+            request,
+            spider=spider,
+            max_retry_times=max_retry_times,
+        )
+        self.assertEqual(new_request, None)
+
+    def test_priority_adjust_setting(self):
+        priority_adjust = 1
+        spider = self.get_spider({'RETRY_PRIORITY_ADJUST': priority_adjust})
+        request = Request('https://example.com')
+        new_request = get_retry_request(
+            request,
+            spider=spider,
+        )
+        self.assertEqual(new_request.priority, priority_adjust)
+
+    def test_priority_adjust_argument(self):
+        priority_adjust = 1
+        spider = self.get_spider({'RETRY_PRIORITY_ADJUST': priority_adjust+1})
+        request = Request('https://example.com')
+        new_request = get_retry_request(
+            request,
+            spider=spider,
+            priority_adjust=priority_adjust,
+        )
+        self.assertEqual(new_request.priority, priority_adjust)
+
+    def test_log_extra_retry_success(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        with LogCapture(attributes=('spider',)) as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+            )
+        log.check_present(spider)
+
+    def test_log_extra_retries_exceeded(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        with LogCapture(attributes=('spider',)) as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                max_retry_times=0,
+            )
+        log.check_present(spider)
+
+    def test_reason_string(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        expected_reason = 'because'
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                reason=expected_reason,
+            )
+        expected_retry_times = 1
+        for stat in ('retry/count', f'retry/reason_count/{expected_reason}'):
+            self.assertEqual(spider.crawler.stats.get_value(stat), 1)
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "DEBUG",
+                f"Retrying {request} (failed {expected_retry_times} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_reason_builtin_exception(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        expected_reason = NotImplementedError()
+        expected_reason_string = 'builtins.NotImplementedError'
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                reason=expected_reason,
+            )
+        expected_retry_times = 1
+        stat = spider.crawler.stats.get_value(
+            f'retry/reason_count/{expected_reason_string}'
+        )
+        self.assertEqual(stat, 1)
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "DEBUG",
+                f"Retrying {request} (failed {expected_retry_times} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_reason_builtin_exception_class(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        expected_reason = NotImplementedError
+        expected_reason_string = 'builtins.NotImplementedError'
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                reason=expected_reason,
+            )
+        expected_retry_times = 1
+        stat = spider.crawler.stats.get_value(
+            f'retry/reason_count/{expected_reason_string}'
+        )
+        self.assertEqual(stat, 1)
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "DEBUG",
+                f"Retrying {request} (failed {expected_retry_times} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_reason_custom_exception(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        expected_reason = IgnoreRequest()
+        expected_reason_string = 'scrapy.exceptions.IgnoreRequest'
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                reason=expected_reason,
+            )
+        expected_retry_times = 1
+        stat = spider.crawler.stats.get_value(
+            f'retry/reason_count/{expected_reason_string}'
+        )
+        self.assertEqual(stat, 1)
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "DEBUG",
+                f"Retrying {request} (failed {expected_retry_times} times): "
+                f"{expected_reason}",
+            )
+        )
+
+    def test_reason_custom_exception_class(self):
+        request = Request('https://example.com')
+        spider = self.get_spider()
+        expected_reason = IgnoreRequest
+        expected_reason_string = 'scrapy.exceptions.IgnoreRequest'
+        with LogCapture() as log:
+            new_request = get_retry_request(
+                request,
+                spider=spider,
+                reason=expected_reason,
+            )
+        expected_retry_times = 1
+        stat = spider.crawler.stats.get_value(
+            f'retry/reason_count/{expected_reason_string}'
+        )
+        self.assertEqual(stat, 1)
+        log.check_present(
+            (
+                "scrapy.downloadermiddlewares.retry",
+                "DEBUG",
+                f"Retrying {request} (failed {expected_retry_times} times): "
+                f"{expected_reason}",
+            )
+        )
+
+
 if __name__ == "__main__":
     unittest.main()