source: perl/modules/Facebook/lib/BarnOwl/Module/Facebook/Handle.pm

release-1.9
Last change on this file was f4037cf, checked in by Edward Z. Yang <ezyang@mit.edu>, 10 years ago
Update README, narrow POSIX import. Signed-off-by: Edward Z. Yang <ezyang@mit.edu>
  • Property mode set to 100644
File size: 17.0 KB
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1use warnings;
2use strict;
3
4=head1 NAME
5
6BarnOwl::Module::Facebook::Handle
7
8=head1 DESCRIPTION
9
10Contains everything needed to send and receive messages from Facebook
11
12=cut
13
14package BarnOwl::Module::Facebook::Handle;
15
16use Facebook::Graph;
17
18use List::Util qw(reduce);
19
20eval { require Lingua::EN::Keywords; };
21if ($@) {
22    *keywords = sub {
23        # stupidly pick the longest one, and only return one.
24        my $sentence = shift;
25        $sentence =~ s/[[:punct:]]+/ /g;
26        my @words = split(' ', lc($sentence));
27        return () unless @words;
28        return (reduce { length($a) > length($b) ? $a : $b } @words);
29    };
30} else {
31    *keywords = \&Lingua::EN::Keywords::keywords;
32}
33
34use JSON;
35use Date::Parse;
36use POSIX qw(asctime);
37use Ouch;
38
39use Scalar::Util qw(weaken);
40
41use BarnOwl;
42use BarnOwl::Message::Facebook;
43
44our $app_id = 235537266461636; # for application 'barnowl'
45
46# Unfortunately, Facebook does not offer a comment stream, in the same
47# way we can get a post stream using the news feed.  This makes it a bit
48# difficult to de-duplicate comments we have already seen.  We use a
49# simple heuristic to fix this: we check if the comment's time is dated
50# from before our last update, and don't re-post if it's dated before.
51# Be somewhat forgiving, since it's better to duplicate a post than to
52# drop one.  Furthermore, we must use Facebook's idea of time, since the
53# server BarnOwl is running on may be desynchronized.  So we need to
54# utilize Facebook's idea of time, not ours.  We do this by looking at
55# all of the timestamps we see while processing an update, and take the
56# latest one and increment it by one second.
57#
58# What properties do we get with this setup?
59#
60#   - We get comment updates only for the latest N posts on a news feed.
61#   Any later ones, you have to use Facebook's usual mechanisms (e.g.
62#   email notifications).
63#
64#   - Processing a poll is relatively expensive, since we have to
65#   iterate over N new posts.  It might be worthwhile polling for new
66#   comments less frequently than polling for new posts.
67
68sub new {
69    my $class = shift;
70    my $cfg = shift;
71
72    my $self = {
73        'cfg' => $cfg,
74        'facebook' => undef,
75
76        # Ideally this should be done using Facebook realtime updates,
77        # but we can't assume that the BarnOwl lives on a publically
78        # addressable server (XXX maybe we can setup an option for this.)
79        'friend_timer' => undef,
80
81        # Initialized with our 'time', but will be synced to Facebook
82        # soon enough. (Subtractive amount is just to preseed with some
83        # values.) XXX Remove subtraction altogether.
84        'last_poll' => time - 60 * 60,
85        'timer' => undef,
86
87        # Message polling not implemented yet
88        #'last_message_poll' => time,
89        #'message_timer' => undef,
90
91        # yeah yeah, inelegant, I know.  You can try using
92        # $fb->authorize, but at time of writing (1.0300) they didn't support
93        # the response_type parameter.
94        # 'login_url' => 'https://www.facebook.com/dialog/oauth?client_id=235537266461636&scope=read_stream,read_mailbox,publish_stream,offline_access,read_friendlists,rsvp_event,user_events&redirect_uri=http://www.facebook.com/connect/login_success.html&response_type=token',
95        # minified to fit in most terminal windows.
96        # Be careful about updating these values, since BarnOwl will not
97        # notice that it is missing necessary permissions until it
98        # attempt to perform an operation which fails due to lack of
99        # permissions.
100        'login_url' => 'http://goo.gl/rcM9s',
101
102        'logged_in' => 0,
103
104        # would need another hash for topic de-dup
105        'topics' => {},
106
107        # deduplicated map of names to user ids
108        'friends' => {},
109    };
110
111    bless($self, $class);
112
113    $self->{facebook} = Facebook::Graph->new(app_id => $app_id);
114    if (defined $self->{cfg}->{token}) {
115        $self->facebook_do_auth;
116    }
117
118    return $self;
119}
120
121=head2 sleep N
122
123Stop polling Facebook for N seconds.
124
125=cut
126
127sub sleep {
128    my $self  = shift;
129    my $delay = shift;
130
131    # prevent reference cycles
132    my $weak = $self;
133    weaken($weak);
134
135    # Stop any existing timers.
136    if (defined $self->{friend_timer}) {
137        $self->{friend_timer}->stop;
138        $self->{friend_timer} = undef;
139    }
140    if (defined $self->{timer}) {
141        $self->{timer}->stop;
142        $self->{timer} = undef;
143    }
144    if (defined $self->{message_timer}) {
145        # XXX doesn't do anything right now
146        $self->{message_timer}->stop;
147        $self->{message_timer} = undef;
148    }
149
150    $self->{friend_timer} = BarnOwl::Timer->new({
151        name     => "Facebook friend poll",
152        after    => $delay,
153        interval => 60 * 60 * 24,
154        cb       => sub { $weak->poll_friends if $weak }
155       });
156    $self->{timer} = BarnOwl::Timer->new({
157        name     => "Facebook poll",
158        after    => $delay,
159        interval => 90,
160        cb       => sub { $weak->poll_facebook if $weak }
161       });
162    # XXX implement message polling
163}
164
165sub check_result {
166    my $self = shift;
167    if (kiss "OAuthException") {
168        $self->{logged_in} = 0;
169        $self->facebook_do_auth;
170        return 0;
171    } elsif (hug) {
172        my $code = $@->code;
173        warn "Poll failed with $code: $@";
174        return 0;
175    }
176    return 1;
177}
178
179sub poll_friends {
180    my $self = shift;
181
182    return unless BarnOwl::getvar('facebook:poll') eq 'on';
183    return unless $self->{logged_in};
184
185    $self->{facebook}->query->find('me/friends')->request(sub {
186        my $response = shift;
187        my $friends = eval { $response->as_hashref };
188        return unless $self->check_result;
189
190        $self->{friends} = {};
191
192        for my $friend (@{$friends->{data}}) {
193            if (defined $self->{friends}{$friend->{name}}) {
194                # XXX We should try a little harder here, rather than just
195                # tacking on a number.  Ideally, we should be able to
196                # calculate some extra piece of information that the user
197                # needs to disambiguate between the two users.  An old
198                # version of Facebook used to disambiguate with your primary
199                # network (so you might have Edward Yang (MIT) and Edward
200                # Yang (Cambridge), the idea being that users in the same
201                # network would probably have already disambiguated
202                # themselves with middle names or nicknames.  We no longer
203                # get network information, since Facebook axed that
204                # information, but the Education/Work fields may still be
205                # a reasonable approximation (but which one do you pick?!
206                # The most recent one.)  Since getting this information
207                # involves extra queries, there are also caching and
208                # efficiency concerns (though hopefully you don't have too
209                # many friends with the same name).  Furthermore, accessing
210                # this information requires a pretty hefty extra set of
211                # permissions requests, which we don't currently ask for.
212                #   It may just be better to let users specify custom
213                # aliases for Facebook users, which are added into this
214                # hash.  See also username support.
215                warn "Duplicate friend name " . $friend->{name};
216                my $name = $friend->{name};
217                my $i = 2;
218                while (defined $self->{friends}{$friend->{name} . ' ' . $i}) { $i++; }
219                $self->{friends}{$friend->{name} . ' ' . $i} = $friend->{id};
220            } else {
221                $self->{friends}{$friend->{name}} = $friend->{id};
222            }
223        }
224
225        # XXX We should also have support for usernames, and not just real
226        # names. However, since this data is not returned by the friends
227        # query, it would require a rather expensive set of queries. We
228        # might try to preserve old data, but all-in-all it's a bit
229        # complicated.  One possible way of fixing this is to construct a
230        # custom FQL query that joins the friends table and the users table.
231    });
232}
233
234sub poll_facebook {
235    my $self = shift;
236
237    return unless BarnOwl::getvar('facebook:poll') eq 'on';
238    return unless $self->{logged_in};
239
240    my $old_topics = $self->{topics};
241    $self->{topics} = {};
242
243    $self->{facebook}
244         ->query
245         ->from("my_news")
246         # Not using this, because we want to pick up comment
247         # updates. We need to manually de-duplicate, though.
248         # ->where_since("@" . $self->{last_poll})
249         # Facebook doesn't actually give us that many results.
250         # But it can't hurt to ask!
251         ->limit_results(200)
252         ->request(sub {
253
254        my $updates = eval { shift->as_hashref };
255        return unless $self->check_result;
256
257        my $new_last_poll = $self->{last_poll};
258        for my $post (reverse @{$updates->{data}}) {
259            # No app invites, thanks! (XXX make configurable)
260            if ($post->{type} eq 'link' && $post->{application}) {
261                next;
262            }
263
264            # XXX Filtering out interest groups for now
265            # A more reasonable strategy may be to show their
266            # posts, but not the comments.
267            if (defined $post->{from}{category}) {
268                next;
269            }
270
271            # There can be multiple recipients! Strange! Pick the first one.
272            my $name    = $post->{to}{data}[0]{name} || $post->{from}{name};
273            my $name_id = $post->{to}{data}[0]{id} || $post->{from}{id};
274            my $post_id  = $post->{id};
275
276            my $topic;
277            if (defined $old_topics->{$post_id}) {
278                $topic = $old_topics->{$post_id};
279                $self->{topics}->{$post_id} = $topic;
280            } else {
281                my @keywords = keywords($post->{name} || $post->{message});
282                $topic = $keywords[0] || 'personal';
283                $topic =~ s/ /-/g;
284                $self->{topics}->{$post_id} = $topic;
285            }
286
287            # XXX The intent is to get the 'Comment' link, which also
288            # serves as a canonical link to the post.  The {name}
289            # field should equal 'Comment'.  But we don't check
290            # this, we assume that the first element is the right one.
291            my $link = $post->{actions}[0]{link};
292
293            # Only handle post if it's new
294            my $created_time = str2time($post->{created_time});
295            if ($created_time >= $self->{last_poll}) {
296                my $msg = BarnOwl::Message->new(
297                    type      => 'Facebook',
298                    sender    => $post->{from}{name},
299                    sender_id => $post->{from}{id},
300                    name      => $name,
301                    name_id   => $name_id,
302                    direction => 'in',
303                    body      => wordwrap($self->format_body($post)),
304                    post_id   => $post_id,
305                    topic     => $topic,
306                    time      => asctime(localtime $created_time),
307                    permalink => $link,
308                   );
309                BarnOwl::queue_message($msg);
310            }
311
312            # This will interleave times (they'll all be organized by parent
313            # post), but since we don't expect too many updates between
314            # polls this is pretty acceptable.
315            my $updated_time = str2time($post->{updated_time});
316            if ($updated_time >= $self->{last_poll} && defined $post->{comments}{data}) {
317                for my $comment (@{$post->{comments}{data}}) {
318                    my $comment_time = str2time($comment->{created_time});
319                    if ($comment_time < $self->{last_poll}) {
320                        next;
321                    }
322                    my $msg = BarnOwl::Message->new(
323                        type      => 'Facebook',
324                        sender    => $comment->{from}{name},
325                        sender_id => $comment->{from}{id},
326                        name      => $name,
327                        name_id   => $name_id,
328                        direction => 'in',
329                        body      => wordwrap($comment->{message}),
330                        post_id   => $post_id,
331                        topic     => $topic,
332                        time      => asctime(localtime $comment_time),
333                        permalink => $link,
334                       );
335                    BarnOwl::queue_message($msg);
336                }
337            }
338            if ($updated_time + 1 > $new_last_poll) {
339                $new_last_poll = $updated_time + 1;
340            }
341        }
342        # old_topics gets GC'd
343
344        $self->{last_poll} = $new_last_poll;
345    });
346}
347
348sub wordwrap {
349    my $text = shift;
350    return BarnOwl::wordwrap($text, BarnOwl::getvar('edit:maxwrapcols'));
351}
352
353sub format_body {
354    my $self = shift;
355
356    my $post = shift;
357
358    # XXX implement optional URL minification
359    if ($post->{type} eq 'status') {
360        return $post->{message};
361    } elsif ($post->{type} eq 'link' || $post->{type} eq 'video' || $post->{type} eq 'photo') {
362        return $post->{name}
363          . ($post->{caption} ? " (" . $post->{caption} . ")\n" : "\n")
364          . $post->{link}
365          . ($post->{description} ? "\n\n" . $post->{description} : "")
366          . ($post->{message} ? "\n\n" . $post->{message} : "");
367    } else {
368        return "(unknown post type " . $post->{type} . ")";
369    }
370}
371
372# Invariant: we don't become logged out between entering text field
373# and actually processing the request.  XXX I don't think this actually
374# holds, but such a case would rarely happen.
375
376sub facebook {
377    my $self = shift;
378
379    my $user = shift;
380    my $msg = shift;
381
382    my $cont = sub {
383        eval { shift->as_hashref };
384        return unless $self->check_result;
385        BarnOwl::message("Submitted!");
386        $self->sleep(1); # give a bit of time to quiesce
387    };
388
389    if (defined $user) {
390        $user = $self->{friends}{$user} || $user;
391        $self->{facebook}->add_post($user)->set_message($msg)->publish($cont);
392    } else {
393        $self->{facebook}->add_post->set_message($msg)->publish($cont);
394    }
395    BarnOwl::message("Submitting Facebook post...");
396}
397
398sub facebook_comment {
399    my $self = shift;
400
401    my $post_id = shift;
402    my $msg = shift;
403
404    $self->{facebook}->add_comment($post_id)->set_message($msg)->publish(sub {
405        eval { shift->as_hashref };
406        return unless $self->check_result;
407        BarnOwl::message("Submitted!");
408        $self->sleep(1); # give a bit of time to quiesce
409    });
410    BarnOwl::message("Submitting Facebook comment...");
411}
412
413sub facebook_auth {
414    my $self = shift;
415
416    my $url = shift;
417
418    if (!defined $url) {
419        $self->facebook_do_auth;
420        return;
421    }
422
423    # http://www.facebook.com/connect/login_success.html#access_token=TOKEN&expires_in=0
424    $url =~ /access_token=([^&]+)/; # XXX Ew regex
425
426    if (!defined $1) {
427        BarnOwl::message("Invalid URL.");
428        return;
429    }
430
431    $self->{cfg}->{token} = $1;
432    $self->facebook_do_auth(sub {
433        my $raw_cfg = to_json($self->{cfg});
434        my $cfg_file;
435        unless (open($cfg_file, ">", BarnOwl::get_config_dir() . "/facebook")) {
436          BarnOwl::admin_message('Facebook', "Add this as the contents of your ~/.owl/facebook file:\n$raw_cfg");
437          return;
438        }
439        print $cfg_file $raw_cfg;
440        close $cfg_file;
441        BarnOwl::admin_message('Facebook', "Saved your login credentials to ~/.owl/facebook.");
442    });
443    return;
444}
445
446sub facebook_do_auth {
447    my $self = shift;
448    my $success = shift || sub {};
449    if (!defined $self->{cfg}->{token}) {
450        BarnOwl::admin_message('Facebook', "Login to Facebook at ".$self->{login_url}
451            . "\nand run command ':facebook-auth URL' with the URL you are redirected to."
452            . "\n\nWhat does BarnOwl use these permissions for?  As a desktop"
453            . "\nmessaging application, we need persistent read/write access to your"
454            . "\nnews feed and your inbox.  Other permissions are for pending"
455            . "\nfeatures: we intend on adding support for event streaming, RSVP,"
456            . "\nand BarnOwl filtering on friend lists."
457        );
458        return 0;
459    }
460    $self->{facebook}->access_token($self->{cfg}->{token});
461    # Do a quick check to see if things are working
462    #$self->{facebook}->query()->find('me')->select_fields('name')->request(sub {
463    # Added 'localtime time' to avoid duplicate checks.
464    $self->{facebook}->add_post->set_message("Logged in to BarnOwl at " . localtime time)->set_privacy('CUSTOM', {friends => 'SELF'})->publish(sub {
465        my $result = eval { shift->as_hashref };
466        if ($@) {
467            BarnOwl::admin_message('Facebook', "Failed to authenticate with '$@'!"
468                . "\nLogin to Facebook at ".$self->{login_url}
469                . "\nand run command ':facebook-auth URL' with the URL you are redirected to.");
470        } else {
471            $self->{facebook}->delete($result->{id}, sub {
472                BarnOwl::admin_message('Facebook', "Successfully logged in to Facebook.");
473                $self->{logged_in} = 1;
474                $self->sleep(0); # start polling
475                $success->();
476            });
477        }
478    });
479}
480
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