1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
from testfixtures import LogCapture
from twisted.internet import defer
from twisted.trial.unittest import TestCase
from scrapy.http import Request
from scrapy.utils.test import get_crawler
from tests.mockserver import MockServer
from tests.spiders import MockServerSpider
class InjectArgumentsDownloaderMiddleware:
"""
Make sure downloader middlewares are able to update the keyword arguments
"""
def process_request(self, request, spider):
if request.callback.__name__ == "parse_downloader_mw":
request.cb_kwargs["from_process_request"] = True
def process_response(self, request, response, spider):
if request.callback.__name__ == "parse_downloader_mw":
request.cb_kwargs["from_process_response"] = True
return response
class InjectArgumentsSpiderMiddleware:
"""
Make sure spider middlewares are able to update the keyword arguments
"""
async def process_start(self, start):
async for request in start:
if request.callback.__name__ == "parse_spider_mw":
request.cb_kwargs["from_process_start"] = True
yield request
def process_spider_input(self, response, spider):
request = response.request
if request.callback.__name__ == "parse_spider_mw":
request.cb_kwargs["from_process_spider_input"] = True
def process_spider_output(self, response, result, spider):
for element in result:
if (
isinstance(element, Request)
and element.callback.__name__ == "parse_spider_mw_2"
):
element.cb_kwargs["from_process_spider_output"] = True
yield element
class KeywordArgumentsSpider(MockServerSpider):
name = "kwargs"
custom_settings = {
"DOWNLOADER_MIDDLEWARES": {
InjectArgumentsDownloaderMiddleware: 750,
},
"SPIDER_MIDDLEWARES": {
InjectArgumentsSpiderMiddleware: 750,
},
}
checks: list[bool] = []
async def start(self):
data = {"key": "value", "number": 123, "callback": "some_callback"}
yield Request(self.mockserver.url("/first"), self.parse_first, cb_kwargs=data)
yield Request(
self.mockserver.url("/general_with"), self.parse_general, cb_kwargs=data
)
yield Request(self.mockserver.url("/general_without"), self.parse_general)
yield Request(self.mockserver.url("/no_kwargs"), self.parse_no_kwargs)
yield Request(
self.mockserver.url("/default"), self.parse_default, cb_kwargs=data
)
yield Request(
self.mockserver.url("/takes_less"), self.parse_takes_less, cb_kwargs=data
)
yield Request(
self.mockserver.url("/takes_more"), self.parse_takes_more, cb_kwargs=data
)
yield Request(self.mockserver.url("/downloader_mw"), self.parse_downloader_mw)
yield Request(self.mockserver.url("/spider_mw"), self.parse_spider_mw)
def parse_first(self, response, key, number):
self.checks.append(key == "value")
self.checks.append(number == 123)
self.crawler.stats.inc_value("boolean_checks", 2)
yield response.follow(
self.mockserver.url("/two"),
self.parse_second,
cb_kwargs={"new_key": "new_value"},
)
def parse_second(self, response, new_key):
self.checks.append(new_key == "new_value")
self.crawler.stats.inc_value("boolean_checks")
def parse_general(self, response, **kwargs):
if response.url.endswith("/general_with"):
self.checks.append(kwargs["key"] == "value")
self.checks.append(kwargs["number"] == 123)
self.checks.append(kwargs["callback"] == "some_callback")
self.crawler.stats.inc_value("boolean_checks", 3)
elif response.url.endswith("/general_without"):
self.checks.append(
kwargs == {} # pylint: disable=use-implicit-booleaness-not-comparison
)
self.crawler.stats.inc_value("boolean_checks")
def parse_no_kwargs(self, response):
self.checks.append(response.url.endswith("/no_kwargs"))
self.crawler.stats.inc_value("boolean_checks")
def parse_default(self, response, key, number=None, default=99):
self.checks.append(response.url.endswith("/default"))
self.checks.append(key == "value")
self.checks.append(number == 123)
self.checks.append(default == 99)
self.crawler.stats.inc_value("boolean_checks", 4)
def parse_takes_less(self, response, key, callback):
"""
Should raise
TypeError: parse_takes_less() got an unexpected keyword argument 'number'
"""
def parse_takes_more(self, response, key, number, callback, other):
"""
Should raise
TypeError: parse_takes_more() missing 1 required positional argument: 'other'
"""
def parse_downloader_mw(
self, response, from_process_request, from_process_response
):
self.checks.append(bool(from_process_request))
self.checks.append(bool(from_process_response))
self.crawler.stats.inc_value("boolean_checks", 2)
def parse_spider_mw(self, response, from_process_spider_input, from_process_start):
self.checks.append(bool(from_process_spider_input))
self.checks.append(bool(from_process_start))
self.crawler.stats.inc_value("boolean_checks", 2)
return Request(self.mockserver.url("/spider_mw_2"), self.parse_spider_mw_2)
def parse_spider_mw_2(self, response, from_process_spider_output):
self.checks.append(bool(from_process_spider_output))
self.crawler.stats.inc_value("boolean_checks", 1)
class TestCallbackKeywordArguments(TestCase):
maxDiff = None
@classmethod
def setUpClass(cls):
cls.mockserver = MockServer()
cls.mockserver.__enter__()
@classmethod
def tearDownClass(cls):
cls.mockserver.__exit__(None, None, None)
@defer.inlineCallbacks
def test_callback_kwargs(self):
crawler = get_crawler(KeywordArgumentsSpider)
with LogCapture() as log:
yield crawler.crawl(mockserver=self.mockserver)
assert all(crawler.spider.checks)
assert len(crawler.spider.checks) == crawler.stats.get_value("boolean_checks")
# check exceptions for argument mismatch
exceptions = {}
for line in log.records:
for key in ("takes_less", "takes_more"):
if key in line.getMessage():
exceptions[key] = line
assert exceptions["takes_less"].exc_info[0] is TypeError
assert str(exceptions["takes_less"].exc_info[1]).endswith(
"parse_takes_less() got an unexpected keyword argument 'number'"
), "Exception message: " + str(exceptions["takes_less"].exc_info[1])
assert exceptions["takes_more"].exc_info[0] is TypeError
assert str(exceptions["takes_more"].exc_info[1]).endswith(
"parse_takes_more() missing 1 required positional argument: 'other'"
), "Exception message: " + str(exceptions["takes_more"].exc_info[1])
|
