path: root/IkiWiki/Plugin/aggregate.pm

#!/usr/bin/perl
# Blog aggregation plugin.
package IkiWiki::Plugin::aggregate;

use warnings;
use strict;
use IkiWiki;

my %feeds;
my %guids;

sub import { #{{{
    IkiWiki::hook(type => "getopt", id => "aggregate", 
        call => \&getopt);
    IkiWiki::hook(type => "checkconfig", id => "aggregate",
        call => \&checkconfig);
    IkiWiki::hook(type => "filter", id => "aggregate", 
        call => \&filter);
    IkiWiki::hook(type => "preprocess", id => "aggregate",
        call => \&preprocess);
        IkiWiki::hook(type => "delete", id => "aggregate",
                call => \&delete);
    IkiWiki::hook(type => "savestate", id => "aggregate",
        call => \&savestate);
} # }}}

sub getopt () { #{{{
        eval q{use Getopt::Long};
        Getopt::Long::Configure('pass_through');
        GetOptions("aggregate" => \$IkiWiki::config{aggregate});
} #}}}

sub checkconfig () { #{{{
    loadstate();
    if ($IkiWiki::config{aggregate}) {
        IkiWiki::loadindex();
        aggregate();
        savestate();
    }
} #}}}

sub filter (@) { #{{{
    my %params=@_;
    my $page=$params{page};

    # Mark all feeds originating on this page as removable;
    # preprocess will unmark those that still exist.
    remove_feeds($page);

    return $params{content};
} # }}}

sub preprocess (@) { #{{{
    my %params=@_;

    foreach my $required (qw{name url dir}) {
        if (! exists $params{$required}) {
            return "[[aggregate plugin missing $required parameter]]";
        }
    }

    my $feed={};
    my $name=$params{name};
    if (exists $feeds{$name}) {
        $feed=$feeds{$name};
    }
    else {
        $feeds{$name}=$feed;
    }
    $feed->{name}=$name;
    $feed->{sourcepage}=$params{page};
    $feed->{url}=$params{url};
    ($feed->{dir})=$params{dir}=~/$IkiWiki::config{wiki_file_regexp}/;
    $feed->{dir}=~s/^\/+//;
    $feed->{feedurl}=defined $params{feedurl} ? $params{feedurl} : $params{url};
    $feed->{updateinterval}=defined $params{updateinterval} ? $params{updateinterval} : 15;
    $feed->{expireage}=defined $params{expireage} ? $params{expireage} : 0;
    $feed->{expirecount}=defined $params{expirecount} ? $params{expirecount} : 0;
    delete $feed->{remove};
    $feed->{lastupdate}=0 unless defined $feed->{lastupdate};
    $feed->{numposts}=0 unless defined $feed->{numposts};
    $feed->{newposts}=0 unless defined $feed->{newposts};
    $feed->{message}="new feed" unless defined $feed->{message};
    while (@_) {
        my $key=shift;
        my $value=shift;
        if ($key eq 'tag') {
            push @{$feed->{tags}}, $value;
        }
    }

    return "<a href=\"".$feed->{url}."\">".$feed->{name}."</a>: ".
           "<i>".$feed->{message}."</i> (".$feed->{numposts}.
           " stored posts; ".$feed->{newposts}." new)";
} # }}}

sub delete (@) { #{{{
    my @files=@_;

    # Remove feed data for removed pages.
    foreach my $file (@files) {
        my $page=IkiWiki::pagename($file);
        remove_feeds($page);
    }
} #}}}

sub loadstate () { #{{{
    if (-e "$IkiWiki::config{wikistatedir}/aggregate") {
        open (IN, "$IkiWiki::config{wikistatedir}/aggregate" ||
            die "$IkiWiki::config{wikistatedir}/aggregate: $!");
        while (<IN>) {
            $_=IkiWiki::possibly_foolish_untaint($_);
            chomp;
            my $data={};
            foreach my $i (split(/ /, $_)) {
                my ($field, $val)=split(/=/, $i, 2);
                if ($field eq "name" || $field eq "message") {
                    $data->{$field}=IkiWiki::pagetitle($val);
                }
                elsif ($field eq "tag") {
                    push @{$data->{tags}}, $val;
                }
                else {
                    $data->{$field}=$val;
                }
            }
            
            if (exists $data->{name}) {
                $feeds{$data->{name}}=$data;
            }
            elsif (exists $data->{guid}) {
                $guids{$data->{guid}}=$data;
            }
        }

        close IN;
    }
} #}}}

sub savestate () { #{{{
    open (OUT, ">$IkiWiki::config{wikistatedir}/aggregate" ||
        die "$IkiWiki::config{wikistatedir}/aggregate: $!");
    foreach my $data (values %feeds, values %guids) {
        if ($data->{remove}) {
            if ($data->{name}) {
                foreach my $guid (values %guids) {
                    if ($guid->{feed} eq $data->{name}) {
                        $guid->{remove}=1;
                    }
                }
            }
            else {
                unlink pagefile($data->{page});
            }
            next;
        }

        my @line;
        foreach my $field (keys %$data) {
            if ($field eq "name" || $field eq "message") {
                push @line, "$field=".IkiWiki::titlepage($data->{$field});
            }
            elsif ($field eq "tags") {
                push @line, "tag=$_" foreach @{$data->{tags}};
            }
            else {
                push @line, "$field=".$data->{$field};
            }
        }
        print OUT join(" ", @line)."\n";
    }
    close OUT;
} #}}}

sub aggregate () { #{{{
    eval q{use XML::Feed};
    die $@ if $@;
    eval q{use HTML::Entities};
    die $@ if $@;

FEED:   foreach my $feed (values %feeds) {
        # TODO: check updateinterval
        $feed->{lastupdate}=time;
        $feed->{newposts}=0;
        $IkiWiki::forcerebuild{$feed->{sourcepage}}=1;

        IkiWiki::debug("checking feed ".$feed->{name}." ...");

        my @urls=XML::Feed->find_feeds($feed->{feedurl});
        if (! @urls) {
            $feed->{message}="could not find feed at ".$feed->{feedurl};
            IkiWiki::debug($feed->{message});
        }
        foreach my $url (@urls) {
            my $f=XML::Feed->parse(URI->new($url));
            if (! $f) {
                $feed->{message}=XML::Feed->errstr;
                IkiWiki::debug($feed->{message});
                next FEED;
            }

            foreach my $entry ($f->entries) {
                add_page(
                    feed => $feed,
                    title => decode_entities($entry->title),
                    link => $entry->link,
                    content => $entry->content->body,
                    guid => defined $entry->id ? $entry->id : time."_".$feed->name,
                    ctime => $entry->issued ? ($entry->issued->epoch || time) : time,
                );
            }
        }
        $feed->{message}="processed ok";
    }

    # TODO: expiry
} #}}}

sub add_page (@) { #{{{
    my %params=@_;

    my $feed=$params{feed};
    my $guid={};
    my $mtime;
    if (exists $guids{$params{guid}}) {
        # updating an existing post
        $guid=$guids{$params{guid}};
    }
    else {
        # new post
        $guid->{guid}=$params{guid};
        $guids{$params{guid}}=$guid;
        $mtime=$params{ctime};
        $feed->{numposts}++;
        $feed->{newposts}++;

        # assign it an unused page
        my $page=$feed->{dir}."/".IkiWiki::titlepage($params{title});
        ($page)=$page=~/$IkiWiki::config{wiki_file_regexp}/;
        if (! defined $page || ! length $page) {
            $page=$feed->{dir}."/item";
        }
        $page=~s/\.\.//g; # avoid ".." directory tricks
        my $c="";
        while (exists $IkiWiki::pagesources{$page.$c} ||
               -e pagefile($page.$c)) {
            $c++
        }
        $guid->{page}=$page;
        IkiWiki::debug("creating new page $page");
    }
    $guid->{feed}=$feed->{name};
    
    # To write or not to write? Need to avoid writing unchanged pages
    # to avoid unneccessary rebuilding. The mtime from rss cannot be
    # trusted; let's use a digest.
    eval q{use Digest::MD5 'md5_hex'};
    my $digest=md5_hex($params{content});
    return unless ! exists $guid->{md5} || $guid->{md5} ne $digest;
    $guid->{md5}=$digest;

    # Create the page.
    my $template=IkiWiki::template("aggregatepost.tmpl", blind_cache => 1);
    my $content=$params{content};
    $params{content}=~s/(?<!\\)\[\[/\\\[\[/g; # escape accidental wikilinks
                                              # and preprocessor stuff
    $template->param(content => $params{content});
    $template->param(url => $feed->{url});
    $template->param(name => $feed->{name});
    $template->param(link => $params{link}) if defined $params{link};
    if (ref $feed->{tags}) {
        $template->param(tags => map { tag => $_ }, @{$feed->{tags}});
    }
    IkiWiki::writefile($guid->{page}.".html", $IkiWiki::config{srcdir},
        $template->output);

    # Set the mtime, this lets the build process get the right creation
    # time on record for the new page.
    utime $mtime, $mtime, pagefile($guid->{page}) if defined $mtime;
} #}}}

sub remove_feeds () { #{{{
    my $page=shift;

    my %removed;
    foreach my $id (keys %feeds) {
        if ($feeds{$id}->{sourcepage} eq $page) {
            $feeds{$id}->{remove}=1;
            $removed{$id}=1;
        }
    }
} #}}}

sub pagefile ($) { #{{{
    my $page=shift;

    return "$IkiWiki::config{srcdir}/$page.html";
} #}}}

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