1 8f7f2f4a 2021-12-17 jrmu ================================================================================
 2 8f7f2f4a 2021-12-17 jrmu 
 3 8f7f2f4a 2021-12-17 jrmu                                  RSSBot Explained
 4 8f7f2f4a 2021-12-17 jrmu 
 5 8f7f2f4a 2021-12-17 jrmu   News feeds are generally handled using RSS feeds. RSS is an open format that
 6 8f7f2f4a 2021-12-17 jrmu   allows websites to quickly show which articles have been updated recently.
 7 8f7f2f4a 2021-12-17 jrmu 
 8 8f7f2f4a 2021-12-17 jrmu   To learn more about RSS, visit: https://rss.softwaregarden.com/aboutrss.html
 9 8f7f2f4a 2021-12-17 jrmu 
10 8f7f2f4a 2021-12-17 jrmu   In RSSBot, we use the XML::RSS::Parser module from CPAN:
11 8f7f2f4a 2021-12-17 jrmu 
12 8f7f2f4a 2021-12-17 jrmu use XML::RSS::Parser;
13 8f7f2f4a 2021-12-17 jrmu 
14 8f7f2f4a 2021-12-17 jrmu   Many of your favorite websites have RSS feeds. Use a search engine to find
15 8f7f2f4a 2021-12-17 jrmu   them. In this example, we will use IRCNow's Almanack:
16 8f7f2f4a 2021-12-17 jrmu 
17 8f7f2f4a 2021-12-17 jrmu my $url = 'https://wiki.ircnow.org/index.php?n=Site.AllRecentChanges?action=rss';
18 8f7f2f4a 2021-12-17 jrmu 
19 8f7f2f4a 2021-12-17 jrmu   You can replace this URL with the RSS feed from your favorite website to
20 8f7f2f4a 2021-12-17 jrmu   change the news that your bot displays.
21 8f7f2f4a 2021-12-17 jrmu 
22 8f7f2f4a 2021-12-17 jrmu   We recommend you download an RSS feed and open it with a text editor to
23 8f7f2f4a 2021-12-17 jrmu   see what the RSS format looks like. Here is one sample:
24 8f7f2f4a 2021-12-17 jrmu 
25 8f7f2f4a 2021-12-17 jrmu <title>Ircnow / Servers</title>
26 8f7f2f4a 2021-12-17 jrmu <link>https://wiki.ircnow.org/index.php?n=Ircnow.Servers</link>
27 8f7f2f4a 2021-12-17 jrmu <dc:contributor>mkf</dc:contributor>
28 8f7f2f4a 2021-12-17 jrmu <dc:date>2021-08-29T15:27:58Z</dc:date>
29 8f7f2f4a 2021-12-17 jrmu <pubDate>Sun, 29 Aug 2021 15:27:58 GMT</pubDate>
30 8f7f2f4a 2021-12-17 jrmu </item>
31 8f7f2f4a 2021-12-17 jrmu <item>
32 8f7f2f4a 2021-12-17 jrmu 
33 8f7f2f4a 2021-12-17 jrmu   Let's take a look at inside the subroutine said:
34 8f7f2f4a 2021-12-17 jrmu 
35 8f7f2f4a 2021-12-17 jrmu sub said {
36 8f7f2f4a 2021-12-17 jrmu 	my $self      = shift;
37 8f7f2f4a 2021-12-17 jrmu 	my $arguments = shift;
38 8f7f2f4a 2021-12-17 jrmu 	if ($arguments->{body} =~ /^!rss/) {
39 8f7f2f4a 2021-12-17 jrmu 		my $p = XML::RSS::Parser->new;
40 8f7f2f4a 2021-12-17 jrmu 		my $feed = $p->parse_uri($url);
41 8f7f2f4a 2021-12-17 jrmu 		foreach my $i ( $feed->query('//item') ) { 
42 8f7f2f4a 2021-12-17 jrmu 			my $title = $i->query('title');
43 8f7f2f4a 2021-12-17 jrmu 			my $contributor = $i->query('dc:contributor');
44 8f7f2f4a 2021-12-17 jrmu 			my $link = $i->query('link');
45 8f7f2f4a 2021-12-17 jrmu 			$self->say(
46 8f7f2f4a 2021-12-17 jrmu 				channel => $arguments->{channel},
47 8f7f2f4a 2021-12-17 jrmu 				body => $title->text_content.' - '.$contributor->text_content.': '.$link->text_content,
48 8f7f2f4a 2021-12-17 jrmu 			);
49 8f7f2f4a 2021-12-17 jrmu 		}
50 8f7f2f4a 2021-12-17 jrmu 	}
51 8f7f2f4a 2021-12-17 jrmu }
52 8f7f2f4a 2021-12-17 jrmu 
53 8f7f2f4a 2021-12-17 jrmu   First, we check if a user types a message that begins with !rss
54 8f7f2f4a 2021-12-17 jrmu 
55 8f7f2f4a 2021-12-17 jrmu 	if ($arguments->{body} =~ /^!rss/) {
56 8f7f2f4a 2021-12-17 jrmu 
57 8f7f2f4a 2021-12-17 jrmu   If the user does, then we create a new Parser object and assign this to $p:
58 8f7f2f4a 2021-12-17 jrmu 
59 8f7f2f4a 2021-12-17 jrmu 		my $p = XML::RSS::Parser->new;
60 8f7f2f4a 2021-12-17 jrmu 
61 8f7f2f4a 2021-12-17 jrmu   Next, we parse (analyze) the feed using $p, and assign this to $feed:
62 8f7f2f4a 2021-12-17 jrmu 
63 8f7f2f4a 2021-12-17 jrmu 		my $feed = $p->parse_uri($url);
64 8f7f2f4a 2021-12-17 jrmu 
65 8f7f2f4a 2021-12-17 jrmu   RSS feeds contain a list of news items, and we need to process each item
66 8f7f2f4a 2021-12-17 jrmu   one at a time. For this task, we will use a foreach loop. We are going
67 8f7f2f4a 2021-12-17 jrmu   to query (ask) $feed for all items, then use the foreach loop to iterate
68 8f7f2f4a 2021-12-17 jrmu   through each item. We assign each item to $i.
69 8f7f2f4a 2021-12-17 jrmu 
70 8f7f2f4a 2021-12-17 jrmu 		foreach my $i ( $feed->query('//item') ) { 
71 8f7f2f4a 2021-12-17 jrmu 
72 8f7f2f4a 2021-12-17 jrmu   Next, we query $i to find the title, contributor, and link of each item.
73 8f7f2f4a 2021-12-17 jrmu   We assign these values to $title, $contributor, and $link.
74 8f7f2f4a 2021-12-17 jrmu 
75 8f7f2f4a 2021-12-17 jrmu 			my $title = $i->query('title');
76 8f7f2f4a 2021-12-17 jrmu 			my $contributor = $i->query('dc:contributor');
77 8f7f2f4a 2021-12-17 jrmu 			my $link = $i->query('link');
78 8f7f2f4a 2021-12-17 jrmu 
79 8f7f2f4a 2021-12-17 jrmu   For each item, we send a message to the channel with the title, contributor,
80 8f7f2f4a 2021-12-17 jrmu   and link.
81 8f7f2f4a 2021-12-17 jrmu 
82 8f7f2f4a 2021-12-17 jrmu 			$self->say(
83 8f7f2f4a 2021-12-17 jrmu 				channel => $arguments->{channel},
84 8f7f2f4a 2021-12-17 jrmu 				body => $title->text_content.' - '.$contributor->text_content.': '.$link->text_content,
85 8f7f2f4a 2021-12-17 jrmu 			);
86 8f7f2f4a 2021-12-17 jrmu 
87 8f7f2f4a 2021-12-17 jrmu ================================================================================
88 8f7f2f4a 2021-12-17 jrmu 
89 8f7f2f4a 2021-12-17 jrmu                                 Further Reading
90 8f7f2f4a 2021-12-17 jrmu 
91 8f7f2f4a 2021-12-17 jrmu   XML::RSS::Parser module: https://metacpan.org/pod/XML::RSS::Parser
92 8f7f2f4a 2021-12-17 jrmu 
93 8f7f2f4a 2021-12-17 jrmu ================================================================================
94 8f7f2f4a 2021-12-17 jrmu 
95 8f7f2f4a 2021-12-17 jrmu                                 Learn about Loops
96 8f7f2f4a 2021-12-17 jrmu 
97 8f7f2f4a 2021-12-17 jrmu   View the file ~/control to learn about control structures for perl.
98 8f7f2f4a 2021-12-17 jrmu 
99 8f7f2f4a 2021-12-17 jrmu ================================================================================