scrapy/tests/test_utils_response.py

785 lines
27 KiB
Python

import unittest
import warnings
from itertools import chain
from pathlib import Path
from urllib.parse import urlparse
import pytest
from xtractmime import BINARY_BYTES, RESOURCE_HEADER_BUFFER_LENGTH
from scrapy.exceptions import ScrapyDeprecationWarning
from scrapy.http import HtmlResponse, Response, TextResponse, XmlResponse
from scrapy.http.headers import Headers
from scrapy.responsetypes import ResponseTypes
from scrapy.utils.misc import load_object
from scrapy.utils.python import to_bytes
from scrapy.utils.response import (
get_meta_refresh,
get_response_class,
open_in_browser,
response_httprepr,
response_status_message,
_get_encoding_or_mime_type_from_headers,
)
__doctests__ = ['scrapy.utils.response']
# https://mimesniff.spec.whatwg.org/#interpreting-the-resource-metadata
PRE_XTRACTMIME_HTML_STARTS = (
b'<!DOCTYPE HTML',
b'<HTML',
)
POST_XTRACTMIME_HTML_STARTS = (
b'<HEAD',
b'<SCRIPT',
b'<IFRAME',
b'<H1',
b'<DIV',
b'<FONT',
b'<TABLE',
b'<A',
b'<STYLE',
b'<TITLE',
b'<B',
b'<BODY',
b'<BR',
b'<P',
b'<!--',
)
NON_BINARY_ASCII_BYTES = (
byte
for byte in (
bytes([byte]) for byte in range(128)
)
if byte not in BINARY_BYTES
)
# https://mimesniff.spec.whatwg.org/#whitespace-byte
WHITESPACE_BYTES = (
b"\t",
b"\n",
b"\x0C",
b"\r",
b" ",
)
def odd_capitalize(value: bytes) -> bytes:
"""Make odd bytes lowecase and even bytes uppercase.
>>> odd_capitalize(b'foobar')
b'fOoBaR'
"""
return b"".join(
bytes([byte]).lower() if index % 2 == 0 else bytes([byte]).upper()
for index, byte in enumerate(value)
)
# Scenarios that work the same with the previously-used, deprecated
# scrapy.responsetypes.responsetypes.from_args
PRE_XTRACTMIME_SCENARIOS = (
# Content-Type determines the type for the HTTP protocol.
*(
(
{
"url": f"{protocol}://example.com/foo",
"headers": Headers(
{"Content-Type": content_type + content_type_parameters}
),
},
response_class,
)
for protocol in ("http", "https")
# Make sure that MIME parameters do not break response class choice.
for content_type_parameters in ("", "; foo=bar")
for content_type, response_class in (
("application/octet-stream", Response),
("text/plain", TextResponse),
("text/html", HtmlResponse),
("text/xml", XmlResponse),
*(
(mime_type, load_object(class_path))
for mime_type, class_path in ResponseTypes.CLASSES.items()
if mime_type not in (
# “Note that XHTML is best parsed as XML”
# https://lxml.de/parsing.html
"application/xhtml+xml",
"application/vnd.wap.xhtml+xml",
)
),
# JavaScript MIME types should trigger a TextResponse.
#
# https://mimesniff.spec.whatwg.org/#javascript-mime-type
*(
(mime_type, TextResponse)
for mime_type in (
'application/javascript',
'application/x-javascript',
'text/ecmascript',
'text/javascript',
'text/javascript1.0',
'text/javascript1.1',
'text/javascript1.2',
'text/javascript1.3',
'text/javascript1.4',
'text/javascript1.5',
'text/jscript',
'text/livescript',
'text/x-ecmascript',
'text/x-javascript',
# Unofficial
'application/x-javascript',
)
),
# JSON MIME types should trigger a TextResponse.
#
# https://mimesniff.spec.whatwg.org/#json-mime-type
*(
(mime_type, TextResponse)
for mime_type in (
'application/json',
'text/json',
# Unofficial
'application/json-amazonui-streaming',
'application/x-json',
)
),
# Binary MIME types should trigger a Response.
#
# https://mimesniff.spec.whatwg.org/#json-mime-type
*(
(mime_type, Response)
for mime_type in (
'application/pdf',
)
),
)
),
# Content-Type triumphs body, except for:
#
# - Binary content mislabeled as plain text due to an Apache bug
# https://mimesniff.spec.whatwg.org/#check-for-apache-bug-flag
# https://mimesniff.spec.whatwg.org/#rules-for-text-or-binary
#
# - Feeds mislabeled as HTML
# https://mimesniff.spec.whatwg.org/#rules-for-distinguishing-if-a-resource-is-a-feed-or-html
*(
(
{
'body': body,
'headers': Headers({'Content-Type': [content_type]}),
},
response_class,
)
for body, content_type, response_class in (
*(
(b'\x00\x01\xff', content_type, TextResponse)
for content_type in (
'text/json',
# text/plain variants *not* affected by the Apache bug
'text/plain; charset=Iso-8859-1',
'text/plain; charset=utf-8',
'text/plain; charset=windows-1252',
)
),
)
),
# Compressed content should be of type Response until uncompressed.
(
{
'headers': Headers(
{
'Content-Encoding': ['zip'],
'Content-Type': ['text/html'],
}
)
},
Response,
),
# We take the file extension of URL paths into account, except for HTTP
# responses, because “they are unreliable and easily spoofed”.
#
# https://mimesniff.spec.whatwg.org/#interpreting-the-resource-metadata
*(
(
{'url': f'{protocol}://example.com/a.{extension}'},
response_class,
)
for protocol in ("file", "ftp")
for extension, response_class in (
("gz", Response),
("html", HtmlResponse),
("json", TextResponse),
("pdf", Response),
("txt", TextResponse),
("xml", XmlResponse),
)
),
# Unlike in a web browser, where an attachment Content-Disposition header
# causes the response to be downloaded, and hence MIME sniffing becomes
# irrelevant, in Scrapy those responses are handled the same as any, and
# hence we take the file extension from Content-Disposition into account
# to choose a response class, as a fallback when there is no Content-Type.
*(
(
{
"url": f"{protocol}://example.com/a",
'headers': Headers(
{
'Content-Disposition': [
'attachment; filename="a.xml"',
]
}
),
},
XmlResponse,
)
for protocol in ("http", "https")
),
*(
(
{
"url": f"{protocol}://example.com/a",
'headers': Headers(
{
'Content-Disposition': [
'attachment; filename="a.html"',
],
"Content-Type": "text/xml",
}
),
},
XmlResponse,
)
for protocol in ("http", "https")
),
*(
(
{
"url": f"{protocol}://example.com/a",
"body": b"<?xml",
'headers': Headers(
{
'Content-Disposition': [
'attachment; filename="a.html"',
],
}
),
},
HtmlResponse,
)
for protocol in ("http", "https")
),
# Without anything else, the body determines the response class.
*(
({"body": body}, response_class)
for body, response_class in (
(b'<html><head><title>Hello</title></head>', HtmlResponse),
(b'<?xml version="1.0" encoding="utf-8"', XmlResponse),
# https://codersblock.com/blog/the-smallest-valid-html5-page/
(b'<!DOCTYPE html>\n<title>.</title>', HtmlResponse),
# https://mimesniff.spec.whatwg.org/#identifying-a-resource-with-an-unknown-mime-type
*(
(prefix + start + b">", HtmlResponse)
for prefix in (
b"",
*(byte for byte in WHITESPACE_BYTES if byte != b"\x0c"),
)
for start in (
set_case(start)
for set_case in (bytes.lower, bytes.upper, odd_capitalize)
for start in PRE_XTRACTMIME_HTML_STARTS
)
),
*(
(prefix + b"<?xml", XmlResponse)
for prefix in (
b"",
*(byte for byte in WHITESPACE_BYTES if byte != b"\x0c"),
)
),
(b"\xfe\xffab", TextResponse),
(b"\xff\xfeab", TextResponse),
(b"\xef\xbb\xbfa", TextResponse),
(b"\x00\x00\x01\x00", Response),
(b"\x00\x00\x02\x00", Response),
(b"\x89PNG\r\n\x1a\n", Response),
(b"MThd\x00\x00\x00\x06", Response),
(b"\x00\x00\x00\x0cftypmp4a", Response),
(b"\x00\x00\x00\x14ftypabcdefghmp4a", Response),
(
# https://github.com/mathiasbynens/small/blob/267b39f682598eebb0dafe7590b1504be79b5cad/webm.webm
(
b"\x1aE\xdf\xa3@ B\x86\x81\x01B\xf7\x81\x01B\xf2\x81\x04B"
b"\xf3\x81\x08B\x82@\x04webm"
),
Response,
),
(
# https://github.com/mathiasbynens/small/blob/267b39f682598eebb0dafe7590b1504be79b5cad/mp3.mp3
(
b"\xff\xe3\x18\xc4\x00\x00\x00\x03H\x00\x00\x00\x00LAME3.9"
b"8.2\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
b"\x00\x00\x00\x00\x00\x00\x00\x00"
),
Response,
),
(b"\x1f\x8b\x08", Response),
(b"PK\x03\x04", Response),
(b"Rar \x1a\x07\x00", Response),
# A body is considered binary if its header (first 1445 bytes)
# contains any binary data byte.
*((byte, Response) for byte in BINARY_BYTES[1:]),
*(
(byte, TextResponse)
for byte in NON_BINARY_ASCII_BYTES
if byte not in (b"\x0c", b"\x1b")
),
*(
(b"a" * (RESOURCE_HEADER_BUFFER_LENGTH - 1) + byte, Response)
for byte in BINARY_BYTES[1:]
),
(b"a" * RESOURCE_HEADER_BUFFER_LENGTH + BINARY_BYTES[0], TextResponse),
)
),
# A Content-Type whose essence is "unknown/unknown", "application/unknown",
# or "*/*" has the same effect as no Content-Type being defined.
#
# https://mimesniff.spec.whatwg.org/#mime-type-sniffing-algorithm
*(
(
{
'body': b'<?xml',
'headers': Headers(
{'Content-Type': [content_type + content_type_suffix]}
),
},
XmlResponse,
)
for content_type_suffix in ("", "; foo=bar")
for content_type in (
"unknown/unknown",
"application/unknown",
"*/*",
)
),
*(
(
{
"url": f"{protocol}://example.com/a",
'headers': Headers(
{
'Content-Disposition': [
'attachment; filename="a.xml"',
],
"Content-Type": [content_type + content_type_suffix],
}
),
},
XmlResponse,
)
for protocol in ("http", "https")
for content_type_suffix in ("", "; foo=bar")
for content_type in (
"unknown/unknown",
"application/unknown",
"*/*",
)
),
)
# Scenarios that work differently with the previously-used, deprecated
# scrapy.responsetypes.responsetypes.from_args
POST_XTRACTMIME_SCENARIOS = (
# Content-Type determines the type for the HTTP protocol.
*(
(
{
"url": f"{protocol}://example.com/foo",
"headers": Headers({"Content-Type": content_type}),
},
response_class,
)
for protocol in ("http", "https")
# Make sure that MIME parameters do not break response class choice.
for content_type_parameters in ("", "; foo=bar")
for content_type, response_class in (
# “Note that XHTML is best parsed as XML”
# https://lxml.de/parsing.html
("application/xhtml+xml", XmlResponse),
("application/vnd.wap.xhtml+xml", XmlResponse),
# JavaScript MIME types should trigger a TextResponse.
#
# https://mimesniff.spec.whatwg.org/#javascript-mime-type
*(
(mime_type, TextResponse)
for mime_type in (
'application/ecmascript',
'application/x-ecmascript',
)
),
# JSON MIME types should trigger a TextResponse.
#
# https://mimesniff.spec.whatwg.org/#json-mime-type
*(
(mime_type, TextResponse)
for mime_type in (
'application/foo+json',
'application/ld+json',
)
),
)
),
# Content-Type triumphs body, except for:
#
# - Binary content mislabeled as plain text due to an Apache bug
# https://mimesniff.spec.whatwg.org/#check-for-apache-bug-flag
# https://mimesniff.spec.whatwg.org/#rules-for-text-or-binary
#
# - Feeds mislabeled as HTML
# https://mimesniff.spec.whatwg.org/#rules-for-distinguishing-if-a-resource-is-a-feed-or-html
(
{
'body': b'a',
'headers': Headers({'Content-Type': ['application/octet-stream']}),
},
Response,
),
*(
(
{
'body': body,
'headers': Headers({'Content-Type': [content_type]}),
},
response_class,
)
for body, content_type, response_class in (
(b'a', 'application/octet-stream', Response),
*(
(b'\x00\x01\xff', content_type, Response)
for content_type in (
'text/plain',
'text/plain; charset=ISO-8859-1',
'text/plain; charset=iso-8859-1',
'text/plain; charset=UTF-8',
)
),
*(
(body, "text/html", XmlResponse)
for body in (
b"<rss",
b"<feed",
(
b"<rdf:RDF "
b"... http://purl.org/rss/1.0/ "
b"... http://www.w3.org/1999/02/22-rdf-syntax-ns#"
),
(
b"<rdf:RDF "
b"... http://www.w3.org/1999/02/22-rdf-syntax-ns# "
b"... http://purl.org/rss/1.0/"
),
)
),
)
),
# If the body is empty, it contains no binary data bytes, hence body-based
# MIME type detection must interpret the result as text.
#
# https://mimesniff.spec.whatwg.org/#identifying-a-resource-with-an-unknown-mime-type
({}, TextResponse),
# We take the file extension of URL paths into account, except for HTTP
# responses, because “they are unreliable and easily spoofed”.
#
# https://mimesniff.spec.whatwg.org/#interpreting-the-resource-metadata
*(
(
{'url': f'{protocol}://example.com/a.{extension}'},
response_class,
)
for protocol in ("file", "ftp")
for extension, response_class in (
# “Note that XHTML is best parsed as XML”
# https://lxml.de/parsing.html
("xhtml", XmlResponse),
)
),
*(
(
{'url': f'{protocol}://example.com/a.html'},
response_class,
)
for protocol, response_class in (
*((protocol, TextResponse) for protocol in ("http", "https")),
)
),
# Unlike in a web browser, where an attachment Content-Disposition header
# causes the response to be downloaded, and hence MIME sniffing becomes
# irrelevant, in Scrapy those responses are handled the same as any, and
# hence we take the file extension from Content-Disposition into account
# to choose a response class, as a fallback when there is no Content-Type.
*(
(
{
"url": f"{protocol}://example.com/a",
'headers': Headers(
{
'Content-Disposition': [
f'attachment; filename="a.{file_extension}"',
],
"Content-Type": {content_type},
}
),
},
response_class,
)
for protocol in ("http", "https")
for file_extension, content_type, response_class in (
("xml", "application/octet-stream", Response),
)
),
# Without anything else, the body determines the response class.
*(
({"body": body}, response_class)
for body, response_class in (
# https://mimesniff.spec.whatwg.org/#identifying-a-resource-with-an-unknown-mime-type
*(
(start + b">", HtmlResponse)
for start in (
set_case(start)
for set_case in (bytes.lower, bytes.upper, odd_capitalize)
for start in POST_XTRACTMIME_HTML_STARTS
)
),
*(
(start + b" ", HtmlResponse)
for start in (
set_case(start)
for set_case in (bytes.lower, bytes.upper, odd_capitalize)
for start in chain(
PRE_XTRACTMIME_HTML_STARTS,
POST_XTRACTMIME_HTML_STARTS,
)
)
),
*(
(b"\x0c" + start + b">", HtmlResponse)
for start in (
set_case(start)
for set_case in (bytes.lower, bytes.upper, odd_capitalize)
for start in PRE_XTRACTMIME_HTML_STARTS
)
),
(b"\x0c<?xml", XmlResponse),
(b'%PDF-', Response),
(b"%!PS-Adobe-", Response),
(b"BM", Response),
(b"GIF87a", Response),
(b"GIF89a", Response),
(b"RIFFabcdWEBPVP", Response),
(b"\xff\xd8\xff", Response),
(b"FORMabcdAIFF", Response),
(b"ID3", Response),
(b"OggS\x00", Response),
(b"RIFFabcdAVI ", Response),
(b"RIFFabcdWAVE", Response),
# A body is considered binary if its header (first 1445 bytes)
# contains any binary data byte.
(BINARY_BYTES[0], Response),
*((byte, TextResponse) for byte in (b"\x0c", b"\x1b")),
(b"a" * (RESOURCE_HEADER_BUFFER_LENGTH - 1) + BINARY_BYTES[0], Response),
*(
(b"a" * RESOURCE_HEADER_BUFFER_LENGTH + byte, TextResponse)
for byte in BINARY_BYTES[1:]
),
# HTML and XML detection does not allow for unexpected content
# before document start.
(b'a<html>', TextResponse),
(b'a<?xml', TextResponse),
)
),
)
@pytest.mark.parametrize(
'kwargs,response_class',
(
*PRE_XTRACTMIME_SCENARIOS,
*POST_XTRACTMIME_SCENARIOS,
),
)
def test_get_response_class_http(kwargs, response_class):
kwargs = dict(kwargs)
if 'headers' in kwargs:
kwargs['http_headers'] = kwargs.pop('headers')
assert get_response_class(**kwargs) == response_class
@pytest.mark.parametrize(
'headers,expected',
(
*(
(
Headers({'Content-Encoding': content_encoding_header}),
(encoding, None),
)
for content_encoding_header, encoding in (
(['gzip'], b'gzip'),
(['gzip', 'compress'], b'compress'),
(['deflate, br'], b'br'),
)
),
),
)
def test_get_encoding_or_mime_type_from_headers(headers, expected):
assert _get_encoding_or_mime_type_from_headers(headers) == expected
class ResponseUtilsTest(unittest.TestCase):
dummy_response = TextResponse(url='http://example.org/', body=b'dummy_response')
def test_response_httprepr(self):
with warnings.catch_warnings():
warnings.simplefilter("ignore", ScrapyDeprecationWarning)
r1 = Response("http://www.example.com")
self.assertEqual(response_httprepr(r1), b'HTTP/1.1 200 OK\r\n\r\n')
r1 = Response("http://www.example.com", status=404,
headers={"Content-type": "text/html"}, body=b"Some body")
self.assertEqual(response_httprepr(r1),
b'HTTP/1.1 404 Not Found\r\nContent-Type: text/html\r\n\r\nSome body')
r1 = Response("http://www.example.com", status=6666,
headers={"Content-type": "text/html"}, body=b"Some body")
self.assertEqual(response_httprepr(r1),
b'HTTP/1.1 6666 \r\nContent-Type: text/html\r\n\r\nSome body')
def test_open_in_browser(self):
url = "http:///www.example.com/some/page.html"
body = b"<html> <head> <title>test page</title> </head> <body>test body</body> </html>"
def browser_open(burl):
path = urlparse(burl).path
if not path or not Path(path).exists():
path = burl.replace('file://', '')
bbody = Path(path).read_bytes()
self.assertIn(b'<base href="' + to_bytes(url) + b'">', bbody)
return True
response = HtmlResponse(url, body=body)
assert open_in_browser(response, _openfunc=browser_open), "Browser not called"
resp = Response(url, body=body)
self.assertRaises(TypeError, open_in_browser, resp, debug=True)
def test_get_meta_refresh(self):
r1 = HtmlResponse("http://www.example.com", body=b"""
<html>
<head><title>Dummy</title><meta http-equiv="refresh" content="5;url=http://example.org/newpage" /></head>
<body>blahablsdfsal&amp;</body>
</html>""")
r2 = HtmlResponse("http://www.example.com", body=b"""
<html>
<head><title>Dummy</title><noScript>
<meta http-equiv="refresh" content="5;url=http://example.org/newpage" /></head>
</noSCRIPT>
<body>blahablsdfsal&amp;</body>
</html>""")
r3 = HtmlResponse("http://www.example.com", body=b"""
<noscript><meta http-equiv="REFRESH" content="0;url=http://www.example.com/newpage</noscript>
<script type="text/javascript">
if(!checkCookies()){
document.write('<meta http-equiv="REFRESH" content="0;url=http://www.example.com/newpage">');
}
</script>
""")
self.assertEqual(get_meta_refresh(r1), (5.0, 'http://example.org/newpage'))
self.assertEqual(get_meta_refresh(r2), (None, None))
self.assertEqual(get_meta_refresh(r3), (None, None))
def test_response_status_message(self):
self.assertEqual(response_status_message(200), '200 OK')
self.assertEqual(response_status_message(404), '404 Not Found')
self.assertEqual(response_status_message(573), "573 Unknown Status")
def test_inject_base_url(self):
url = "http://www.example.com"
def check_base_url(burl):
path = urlparse(burl).path
if not path or not Path(path).exists():
path = burl.replace('file://', '')
bbody = Path(path).read_bytes()
self.assertEqual(bbody.count(b'<base href="' + to_bytes(url) + b'">'), 1)
return True
r1 = HtmlResponse(url, body=b"""
<html>
<head><title>Dummy</title></head>
<body><p>Hello world.</p></body>
</html>""")
r2 = HtmlResponse(url, body=b"""
<html>
<head id="foo"><title>Dummy</title></head>
<body>Hello world.</body>
</html>""")
r3 = HtmlResponse(url, body=b"""
<html>
<head><title>Dummy</title></head>
<body>
<header>Hello header</header>
<p>Hello world.</p>
</body>
</html>""")
r4 = HtmlResponse(url, body=b"""
<html>
<!-- <head>Dummy comment</head> -->
<head><title>Dummy</title></head>
<body><p>Hello world.</p></body>
</html>""")
r5 = HtmlResponse(url, body=b"""
<html>
<!--[if IE]>
<head><title>IE head</title></head>
<![endif]-->
<!--[if !IE]>-->
<head><title>Standard head</title></head>
<!--<![endif]-->
<body><p>Hello world.</p></body>
</html>""")
assert open_in_browser(r1, _openfunc=check_base_url), "Inject base url"
assert open_in_browser(r2, _openfunc=check_base_url), "Inject base url with argumented head"
assert open_in_browser(r3, _openfunc=check_base_url), "Inject unique base url with misleading tag"
assert open_in_browser(r4, _openfunc=check_base_url), "Inject unique base url with misleading comment"
assert open_in_browser(r5, _openfunc=check_base_url), "Inject unique base url with conditional comment"