-
Notifications
You must be signed in to change notification settings - Fork 58
/
Copy pathblog_webmention.py
220 lines (187 loc) · 7.84 KB
/
blog_webmention.py
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
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
"""Converts webmentions to comments on Blogger, Tumblr, and WP.com."""
import logging
import urllib.parse
from flask import request
from granary import microformats2
from oauth_dropins.webutil.util import get_first
from flask_app import app
import models
from models import BlogWebmention
import util
import webmention
logger = logging.getLogger(__name__)
class BlogWebmentionView(webmention.Webmention):
"""View for incoming webmentions against blog providers."""
def dispatch_request(self, site):
logger.info(f'Params: {list(request.values.items())}')
# strip fragments from source and target url
self.source_url = urllib.parse.urldefrag(request.form['source'])[0]
self.target_url = urllib.parse.urldefrag(request.form['target'])[0]
# follow target url through any redirects, strip utm_* query params
resp = util.follow_redirects(self.target_url)
redirected_target_urls = [r.url for r in resp.history]
self.target_url = util.clean_url(resp.url)
# parse and validate target URL
domain = util.domain_from_link(self.target_url)
if not domain:
self.error(f'Could not parse target URL {self.target_url}')
# look up source by domain
source_cls = models.sources[site]
domain = domain.lower()
self.source = (source_cls.query()
.filter(source_cls.domains == domain)
.filter(source_cls.features == 'webmention')
.filter(source_cls.status == 'enabled')
.get())
if not self.source:
# check for a rel-canonical link. Blogger uses these when it serves a post
# from multiple domains, e.g country TLDs like epeus.blogspot.co.uk vs
# epeus.blogspot.com.
# https://github.com/snarfed/bridgy/issues/805
mf2 = self.fetch_mf2(self.target_url, require_mf2=False)
if not mf2:
# fetch_mf2() already wrote the error response
return
domains = util.dedupe_urls(
util.domain_from_link(url)
for url in mf2[1]['rels'].get('canonical', []))
if domains:
self.source = (source_cls.query()
.filter(source_cls.domains.IN(domains))
.filter(source_cls.features == 'webmention')
.filter(source_cls.status == 'enabled')
.get())
if not self.source:
self.error(
f'Could not find {source_cls.GR_CLASS.NAME} account for {domain}. Is it registered with Bridgy?')
# check that the target URL path is supported
target_path = urllib.parse.urlparse(self.target_url).path
if target_path in ('', '/'):
msg = 'Home page webmentions are not currently supported.'
logger.info(msg)
return {'error': msg}, 202
for pattern in self.source.PATH_BLOCKLIST:
if pattern.match(target_path):
msg = f'{self.source.GR_CLASS.NAME} webmentions are not supported for URL path: {target_path}'
logger.info(msg)
return {'error': msg}, 202
# create BlogWebmention entity
id = f'{self.source_url} {self.target_url}'
self.entity = BlogWebmention.get_or_insert(
id, source=self.source.key, redirected_target_urls=redirected_target_urls)
if self.entity.status == 'complete':
# TODO: response message saying update isn't supported
return self.entity.published
logger.debug(f'BlogWebmention entity: {self.entity.key.urlsafe().decode()}')
# fetch source page
fetched = self.fetch_mf2(self.source_url)
if not fetched:
return
resp, mf2 = fetched
item = self.find_mention_item(mf2.get('items', []))
if not item:
self.error(f'Could not find target URL {self.target_url} in source page {resp.url}', data=mf2, log_exception=False)
# default author to target domain
author_name = domain
author_url = f'http://{domain}/'
# extract author name and URL from h-card, if any
props = item['properties']
author = get_first(props, 'author')
if author:
if isinstance(author, str):
author_name = author
else:
author_props = author.get('properties', {})
author_name = get_first(author_props, 'name')
author_url = get_first(author_props, 'url')
# if present, u-url overrides source url
u_url = get_first(props, 'url')
if u_url:
self.entity.u_url = u_url
# generate content
content = props['content'][0] # find_mention_item() guaranteed this is here
text = (content.get('html') or content.get('value')).strip()
source_url = self.entity.source_url()
text += f' <br /> <a href="{source_url}">via {util.domain_from_link(source_url)}</a>'
# write comment
try:
self.entity.published = self.source.create_comment(
self.target_url, author_name, author_url, text)
except Exception as e:
code, body = util.interpret_http_exception(e)
msg = f'Error: {code}: {e}; {body}'
if code == '401':
logger.warning(f'Disabling source due to: {e}', exc_info=True)
self.source.status = 'disabled'
self.source.put()
self.error(msg, status=code, report=self.source.is_beta_user())
elif code == '404':
# post is gone
self.error(msg, status=code, report=False)
elif util.is_connection_failure(e) or (code and int(code) // 100 == 5):
self.error(msg, status=502, report=False)
elif code or body:
self.error(msg, status=code, report=True)
else:
raise
# write results to datastore
self.entity.status = 'complete'
self.entity.put()
return self.entity.published
def find_mention_item(self, items):
"""Returns the mf2 item that mentions (or replies to, likes, etc) the target.
May modify the items arg, e.g. may set or replace content.html or
content.value.
Args:
items (list of dict): mf2 items
Returns:
dict: mf2 item, or None
"""
# find target URL in source
for item in items:
props = item.setdefault('properties', {})
# find first non-empty content element
content = props.setdefault('content', [{}])[0]
text = content.get('html') or content.get('value')
for type in 'in-reply-to', 'like-of', 'repost-of':
urls = [urllib.parse.urldefrag(u)[0] for u in
microformats2.get_string_urls(props.get(type, []))]
if self.any_target_in(urls):
break
else:
if text and self.any_target_in(text):
type = 'post'
url = get_first(props, 'url') or self.source_url
name = get_first(props, 'name') or get_first(props, 'summary')
text = content['html'] = f'mentioned this in {util.pretty_link(url, text=name, max_length=280)}.'
else:
type = None
if type:
# found the target!
rsvp = get_first(props, 'rsvp')
if rsvp:
self.entity.type = 'rsvp'
if not text:
content['value'] = f'RSVPed {rsvp}.'
else:
self.entity.type = {'in-reply-to': 'comment',
'like-of': 'like',
'repost-of': 'repost',
}.get(type, type)
if not text:
content['value'] = {'comment': 'replied to this.',
'like': 'liked this.',
'repost': 'reposted this.',
}[self.entity.type]
return item
# check children in case this is eg an h-feed
found = self.find_mention_item(item.get('children', []))
if found:
return found
return None
def any_target_in(self, haystack):
"""Returns true if any target URL (including redirects) is in haystack."""
return any(url in haystack
for url in self.entity.redirected_target_urls + [self.target_url])
app.add_url_rule('/webmention/<any(blogger,fake,tumblr,wordpress):site>',
view_func=BlogWebmentionView.as_view('blog_wm'), methods=['POST'])