scrapy/tests/test_downloadermiddleware_r...

478 lines
18 KiB
Python

import logging
from unittest.mock import MagicMock
import pytest
from scrapy.downloadermiddlewares.redirect import RedirectMiddleware
from scrapy.exceptions import NotConfigured
from scrapy.http import Request, Response
from scrapy.spidermiddlewares.referer import (
POLICY_NO_REFERRER,
POLICY_ORIGIN,
POLICY_UNSAFE_URL,
RefererMiddleware,
)
from scrapy.spiders import Spider
from scrapy.utils.misc import build_from_crawler
from scrapy.utils.spider import DefaultSpider
from scrapy.utils.test import get_crawler
from tests.test_downloadermiddleware_redirect_base import (
REDIRECT_SCHEME_CASES,
SCHEME_PARAMS,
Base,
)
class TestRedirectMiddleware(Base.Test):
mwcls = RedirectMiddleware
reason = 302
def setup_method(self):
crawler = get_crawler(DefaultSpider)
crawler.spider = crawler._create_spider()
self.mw = self.mwcls.from_crawler(crawler)
def get_response(self, request, location, status=302):
headers = {"Location": location}
return Response(request.url, status=status, headers=headers)
def test_redirect_3xx_permanent(self):
def _test(method, status: int):
url = f"http://www.example.com/{status}"
url2 = "http://www.example.com/redirected"
req = Request(url, method=method)
rsp = Response(url, headers={"Location": url2}, status=status)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == url2
assert req2.method == method
# response without Location header but with status code is 3XX should be ignored
del rsp.headers["Location"]
assert self.mw.process_response(req, rsp) is rsp
_test("GET", status=307)
_test("POST", status=307)
_test("HEAD", status=307)
_test("GET", status=308)
_test("POST", status=308)
_test("HEAD", status=308)
@pytest.mark.parametrize("status", [301, 302, 303])
def test_method_becomes_get(self, status):
source_url = f"http://www.example.com/{status}"
target_url = "http://www.example.com/redirected2"
request = Request(
source_url,
method="POST",
body="test",
headers={"Content-Type": "text/plain", "Content-length": "4"},
)
response = Response(source_url, headers={"Location": target_url}, status=status)
redirect_request = self.mw.process_response(request, response)
assert isinstance(redirect_request, Request)
assert redirect_request.url == target_url
assert redirect_request.method == "GET"
assert "Content-Type" not in redirect_request.headers
assert "Content-Length" not in redirect_request.headers
assert not redirect_request.body
@pytest.mark.parametrize("status", [301, 302])
@pytest.mark.parametrize("method", ["PUT", "DELETE"])
def test_method_not_converted_on_301_302(self, status, method):
url = f"http://www.example.com/{status}"
url2 = "http://www.example.com/redirected"
body = b"test-body"
req = Request(
url,
method=method,
body=body,
headers={"Content-Type": "text/plain", "Content-Length": str(len(body))},
)
rsp = Response(url, headers={"Location": url2}, status=status)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == url2
assert req2.method == method
assert req2.body == body
assert req2.headers[b"Content-Type"] == b"text/plain"
assert req2.headers[b"Content-Length"] == str(len(body)).encode()
@pytest.mark.parametrize("method", ["PUT", "DELETE"])
def test_method_converted_on_303(self, method):
status = 303
url = f"http://www.example.com/{status}"
url2 = "http://www.example.com/redirected"
req = Request(url, method=method)
rsp = Response(url, headers={"Location": url2}, status=status)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == url2
assert req2.method == "GET"
def test_get_method_body_preserved_on_303(self):
status = 303
url = f"http://www.example.com/{status}"
url2 = "http://www.example.com/redirected"
body = b"test-body"
req = Request(
url,
method="GET",
body=body,
headers={"Content-Type": "text/plain", "Content-Length": str(len(body))},
)
rsp = Response(url, headers={"Location": url2}, status=status)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == url2
assert req2.method == "GET"
assert req2.body == body
assert req2.headers[b"Content-Type"] == b"text/plain"
assert req2.headers[b"Content-Length"] == str(len(body)).encode()
def test_redirect_strips_content_headers(self):
url = "http://www.example.com/303"
url2 = "http://www.example.com/redirected"
headers = {
"Content-Type": "application/json",
"Content-Length": "100",
"Content-Encoding": "gzip",
"Content-Language": "en",
"Content-Location": "http://www.example.com/original",
"X-Custom": "foo",
}
req = Request(url, method="POST", headers=headers, body=b"foo")
rsp = Response(url, headers={"Location": url2}, status=303)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == url2
assert req2.method == "GET"
assert req2.body == b""
assert "Content-Type" not in req2.headers
assert "Content-Length" not in req2.headers
assert "Content-Encoding" not in req2.headers
assert "Content-Language" not in req2.headers
assert "Content-Location" not in req2.headers
assert req2.headers["X-Custom"] == b"foo"
@pytest.mark.parametrize(
(
"referer",
"source_url",
"target_url",
"policy_header",
"expected_referer",
),
[
(
None,
"http://www.example.com/302",
"http://www.example.com/redirected",
None,
b"http://www.example.com/302",
),
(
"http://example.com/old",
"http://www.example.com/302",
"http://www.example.com/redirected",
None,
b"http://www.example.com/302",
),
(
"https://example.com/old",
"https://www.example.com/302",
"http://www.example.com/redirected",
None,
None,
),
(
"http://example.com/old",
"http://www.example.com/foo/bar",
"http://www.example.com/redirected",
"origin",
b"http://www.example.com/",
),
],
)
def test_redirect_referer(
self, referer, source_url, target_url, policy_header, expected_referer
):
headers = {"Referer": referer} if referer else {}
source_request = Request(source_url, headers=headers)
resp_headers = {"Location": target_url}
if policy_header:
resp_headers["Referrer-Policy"] = policy_header
response = Response(source_url, headers=resp_headers, status=302)
crawler = get_crawler()
referer_mw = build_from_crawler(RefererMiddleware, crawler)
redirect_mw = self.mwcls.from_crawler(crawler)
redirect_mw._referer_spider_middleware = referer_mw
redirect_request = redirect_mw.process_response(source_request, response)
if expected_referer:
assert redirect_request.headers.get("Referer") == expected_referer
else:
assert "Referer" not in redirect_request.headers
def test_redirect_strips_referer_no_middleware(self):
source_url = "http://www.example.com/302"
redirect_url = "http://www.example.com/redirected"
source_request = Request(
source_url, headers={"Referer": "http://example.com/old"}
)
response = Response(source_url, headers={"Location": redirect_url}, status=302)
redirect_mw = self.mwcls.from_crawler(get_crawler())
redirect_mw._referer_spider_middleware = None
redirect_request = redirect_mw.process_response(source_request, response)
assert "Referer" not in redirect_request.headers
@pytest.mark.parametrize("status", [307, 308])
def test_cross_origin_maintain_body(self, status):
source_url = "https://example.com"
target_url = "https://attacker.example"
body = b"secret"
request = Request(
source_url,
method="POST",
body=body,
headers={
"Content-Type": "application/json",
"Content-Length": str(len(body)),
},
)
response1 = Response(
source_url, headers={"Location": target_url}, status=status
)
redirect_request = self.mw.process_response(request, response1)
assert isinstance(redirect_request, Request)
assert redirect_request.url == target_url
assert redirect_request.method == "POST"
assert redirect_request.body == body
assert redirect_request.headers[b"Content-Type"] == b"application/json"
assert redirect_request.headers[b"Content-Length"] == str(len(body)).encode()
def test_redirect_keeps_fragment(self):
url = "http://www.example.com/301#frag"
url2 = "http://www.example.com/redirected"
req = Request(url)
rsp = Response(url, headers={"Location": url2}, status=302)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == "http://www.example.com/redirected#frag"
def test_redirect_target_has_fragment(self):
url = "http://www.example.com/302#original"
url2 = "http://www.example.com/redirected#target"
req = Request(url)
rsp = Response(url, headers={"Location": url2}, status=302)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == "http://www.example.com/redirected#target"
def test_redirect_302_head(self):
url = "http://www.example.com/302"
url2 = "http://www.example.com/redirected2"
req = Request(url, method="HEAD")
rsp = Response(url, headers={"Location": url2}, status=302)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == url2
assert req2.method == "HEAD"
def test_redirect_302_relative(self):
url = "http://www.example.com/302"
url2 = "///i8n.example2.com/302"
url3 = "http://i8n.example2.com/302"
req = Request(url, method="HEAD")
rsp = Response(url, headers={"Location": url2}, status=302)
req2 = self.mw.process_response(req, rsp)
assert isinstance(req2, Request)
assert req2.url == url3
assert req2.method == "HEAD"
def test_spider_handling(self):
self.mw.crawler.spider.handle_httpstatus_list = [404, 301, 302]
url = "http://www.example.com/301"
url2 = "http://www.example.com/redirected"
req = Request(url)
rsp = Response(url, headers={"Location": url2}, status=301)
r = self.mw.process_response(req, rsp)
assert r is rsp
def test_request_meta_handling(self):
url = "http://www.example.com/301"
url2 = "http://www.example.com/redirected"
def _test_passthrough(req):
rsp = Response(url, headers={"Location": url2}, status=301, request=req)
r = self.mw.process_response(req, rsp)
assert r is rsp
_test_passthrough(
Request(url, meta={"handle_httpstatus_list": [404, 301, 302]})
)
_test_passthrough(Request(url, meta={"handle_httpstatus_all": True}))
def test_latin1_location(self):
req = Request("http://scrapytest.org/first")
latin1_location = "/ação".encode("latin1") # HTTP historically supports latin1
resp = Response(
"http://scrapytest.org/first",
headers={"Location": latin1_location},
status=302,
)
req_result = self.mw.process_response(req, resp)
perc_encoded_utf8_url = "http://scrapytest.org/a%E7%E3o"
assert perc_encoded_utf8_url == req_result.url
def test_utf8_location(self):
req = Request("http://scrapytest.org/first")
utf8_location = "/ação".encode() # header using UTF-8 encoding
resp = Response(
"http://scrapytest.org/first",
headers={"Location": utf8_location},
status=302,
)
req_result = self.mw.process_response(req, resp)
perc_encoded_utf8_url = "http://scrapytest.org/a%C3%A7%C3%A3o"
assert perc_encoded_utf8_url == req_result.url
def test_no_location(self):
request = Request("https://example.com")
response = Response(request.url, status=302)
assert self.mw.process_response(request, response) is response
@pytest.mark.parametrize(SCHEME_PARAMS, REDIRECT_SCHEME_CASES)
def test_redirect_schemes(url, location, target):
crawler = get_crawler(Spider)
mw = RedirectMiddleware.from_crawler(crawler)
request = Request(url)
response = Response(url, headers={"Location": location}, status=301)
redirect = mw.process_response(request, response)
if target is None:
assert redirect == response
else:
assert isinstance(redirect, Request)
assert redirect.url == target
@pytest.mark.parametrize(
("policy", "source_url", "target_url", "expected_referrer"),
[
# The policy header affects the outcome.
# (without it, the https → http switch would drop the referer)
(
POLICY_UNSAFE_URL,
"https://a.example/1",
"http://a.example/2",
b"https://a.example/1",
),
# The policy header can get the Referer header removed.
(
POLICY_NO_REFERRER,
"http://a.example/1",
"http://a.example/2",
None,
),
# The policy header can get the Referer header edited (path stripped).
(
POLICY_ORIGIN,
"http://a.example/1",
"http://a.example/2",
b"http://a.example/",
),
],
)
def test_response_referrer_policy(policy, source_url, target_url, expected_referrer):
crawler = get_crawler()
referrer_mw = build_from_crawler(RefererMiddleware, crawler)
redirect_mw = build_from_crawler(RedirectMiddleware, crawler)
redirect_mw._referer_spider_middleware = referrer_mw
source_request = Request(source_url)
extra_headers = {}
if policy:
extra_headers["Referrer-Policy"] = policy
response_redirect = Response(
source_request.url,
status=301,
headers={"Location": target_url, **extra_headers},
)
source_request = redirect_mw.process_response(source_request, response_redirect)
assert isinstance(source_request, Request)
assert source_request.headers.get("Referer") == expected_referrer
def test_no_warning_when_referer_middleware_present(caplog):
crawler = get_crawler()
crawler.get_spider_middleware = MagicMock(return_value=MagicMock())
mw = build_from_crawler(RedirectMiddleware, crawler)
caplog.clear()
with caplog.at_level(logging.WARNING):
mw._engine_started()
assert not [
record
for record in caplog.records
if record.name == "scrapy.downloadermiddlewares.redirect"
]
def test_warning_redirect_middleware(caplog):
crawler = get_crawler()
crawler.get_spider_middleware = MagicMock(return_value=None)
mw = build_from_crawler(RedirectMiddleware, crawler)
with caplog.at_level(logging.WARNING):
mw._engine_started()
assert (
"scrapy.downloadermiddlewares.redirect.RedirectMiddleware found no "
"scrapy.spidermiddlewares.referer.RefererMiddleware"
) in caplog.text
assert (
"enable scrapy.spidermiddlewares.referer.RefererMiddleware (or a subclass)"
in caplog.text
)
assert (
"replace scrapy.downloadermiddlewares.redirect.RedirectMiddleware "
"with a subclass that overrides the handle_referer() method"
) in caplog.text
def test_warning_subclass(caplog):
class MyRedirectMiddleware(RedirectMiddleware):
pass
crawler = get_crawler()
crawler.get_spider_middleware = MagicMock(return_value=None)
mw = build_from_crawler(MyRedirectMiddleware, crawler)
with caplog.at_level(logging.WARNING):
mw._engine_started()
assert (
"test_warning_subclass.<locals>.MyRedirectMiddleware found no "
"scrapy.spidermiddlewares.referer.RefererMiddleware"
) in caplog.text
assert (
"enable scrapy.spidermiddlewares.referer.RefererMiddleware (or a subclass)"
in caplog.text
)
assert "edit " in caplog.text
assert "test_warning_subclass.<locals>.MyRedirectMiddleware" in caplog.text
assert (
"(if defined in your code base) to override the handle_referer() method"
) in caplog.text
def test_not_configured():
crawler = get_crawler(DefaultSpider, {"REDIRECT_ENABLED": False})
with pytest.raises(NotConfigured):
RedirectMiddleware.from_crawler(crawler)