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+Here's Thomas Schwinge unfinished darcs support for ikiwiki.
+
+(Finishing this has been suggested as a [[soc]] project.)
+
+> I haven't been working on this for months and also won't in the near
+> future. Feel free to use what I have done so
+> far and bring it into an usable state! Also, feel free to contact me
+> if there are questions.
+
+-- [Thomas Schwinge](mailto:tschwinge@gnu.org)
+
+[[toggle text="show"]]
+[[toggleable text="""
+ # Support for the darcs rcs, <URL:http://darcs.net/>.
+ # Copyright (C) 2006 Thomas Schwinge <tschwinge@gnu.org>
+ #
+ # This program is free software; you can redistribute it and/or modify it
+ # under the terms of the GNU General Public License as published by the
+ # Free Software Foundation; either version 2 of the License, or (at your
+ # option) any later version.
+ #
+ # This program is distributed in the hope that it will be useful, but
+ # WITHOUT ANY WARRANTY; without even the implied warranty of
+ # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ # General Public License for more details.
+ #
+ # You should have received a copy of the GNU General Public License along
+ # with this program; if not, write to the Free Software Foundation, Inc.,
+ # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+
+ # We're guaranteed to be the only instance of ikiwiki running at a given
+ # time. It is essential that only ikiwiki is working on a particular
+ # repository. That means one instance of ikiwiki and it also means that
+ # you must not `darcs push' into this repository, as this might create
+ # race conditions, as I understand it.
+
+
+ use warnings;
+ use strict;
+ use IkiWiki;
+
+ package IkiWiki;
+
+
+ # Which darcs executable to use.
+ my $darcs = ($ENV{DARCS} or 'darcs');
+
+
+ # Internal functions.
+
+ sub darcs_info ($$$) {
+ my $field = shift;
+ my $repodir = shift;
+ my $file = shift; # Relative to the repodir.
+
+ my $child = open(DARCS_CHANGES, "-|");
+ if (! $child) {
+ exec($darcs, 'changes', '--repo=' . $repodir, '--xml-output', $file) or
+ error('failed to run `darcs changes\'');
+ }
+
+ # Brute force for now. :-/
+ while (<DARCS_CHANGES>) {
+ last if /^<\/created_as>$/;
+ }
+ ($_) = <DARCS_CHANGES> =~ /$field=\'([^\']+)/;
+ $field eq 'hash' and s/\.gz//; # Strip away the `.gz' from `hash'es.
+
+ close(DARCS_CHANGES) or error('`darcs changes\' exited ' . $?);
+
+ return $_;
+ }
+
+
+ # Exported functions.
+
+ sub rcs_update () {
+ # Not needed.
+ }
+
+ sub rcs_prepedit ($) {
+ # Prepares to edit a file under revision control. Returns a token that
+ # must be passed to rcs_commit() when the file is to be commited. For us,
+ # this token the hash value of the latest patch that modifies the file,
+ # i.e. something like its current revision. If the file is not yet added
+ # to the repository, we return TODO: the empty string.
+
+ my $file = shift; # Relative to the repodir.
+
+ my $hash = darcs_info('hash', $config{srcdir}, $file);
+ return defined $hash ? $hash : "";
+ }
+
+ sub rcs_commit ($$$) {
+ # Commit the page. Returns `undef' on success and a version of the page
+ # with conflict markers on failure.
+
+ my $file = shift; # Relative to the repodir.
+ my $message = shift;
+ my $rcstoken = shift;
+
+ # Compute if the ``revision'' of $file changed.
+ my $changed = darcs_info('hash', $config{srcdir}, $file) ne $rcstoken;
+
+ # Yes, the following is a bit convoluted.
+ if ($changed) {
+ # TODO. Invent a better, non-conflicting name.
+ rename("$config{srcdir}/$file", "$config{srcdir}/$file.save") or
+ error("failed to rename $file to $file.save: $!");
+
+ # Roll the repository back to $rcstoken.
+
+ # TODO. Can we be sure that no changes are lost? I think that
+ # we can, if we make sure that the `darcs push' below will always
+ # succeed.
+
+ # We need to revert everything as `darcs obliterate' might choke
+ # otherwise.
+ # TODO: `yes | ...' needed? Doesn't seem so.
+ system($darcs, "revert", "--repodir=" . $config{srcdir}, "--all") and
+ error("`darcs revert' failed");
+ # Remove all patches starting at $rcstoken.
+ # TODO. Something like `yes | darcs obliterate ...' seems to be needed.
+ system($darcs, "obliterate", "--quiet", "--repodir" . $config{srcdir},
+ "--match", "hash " . $rcstoken) and
+ error("`darcs obliterate' failed");
+ # Restore the $rcstoken one.
+ system($darcs, "pull", "--quiet", "--repodir=" . $config{srcdir},
+ "--match", "hash " . $rcstoken, "--all") and
+ error("`darcs pull' failed");
+
+ # We're back at $rcstoken. Re-install the modified file.
+ rename("$config{srcdir}/$file.save", "$config{srcdir}/$file") or
+ error("failed to rename $file.save to $file: $!");
+ }
+
+ # Record the changes.
+ # TODO: What if $message is empty?
+ writefile("$file.log", $config{srcdir}, $message);
+ system($darcs, 'record', '--repodir=' . $config{srcdir}, '--all',
+ '--logfile=' . "$config{srcdir}/$file.log",
+ '--author=' . 'web commit <web-hurd@gnu.org>', $file) and
+ error('`darcs record\' failed');
+
+ # Update the repository by pulling from the default repository, which is
+ # master repository.
+ system($darcs, "pull", "--quiet", "--repodir=" . $config{srcdir},
+ "--all") and error("`darcs pull' failed\n");
+
+ # If this updating yields any conflicts, we'll record them now to resolve
+ # them. If nothing is recorded, there are no conflicts.
+ $rcstoken = darcs_info('hash', $config{srcdir}, $file);
+ # TODO: Use only the first line here, i.e. only the patch name?
+ writefile("$file.log", $config{srcdir}, 'resolve conflicts: ' . $message);
+ system($darcs, 'record', '--repodir=' . $config{srcdir}, '--all',
+ '--logfile=' . "$config{srcdir}/$file.log",
+ '--author=' . 'web commit <web-hurd@gnu.org>', $file) and
+ error('`darcs record\' failed');
+ my $conflicts = darcs_info('hash', $config{srcdir}, $file) ne $rcstoken;
+ unlink("$config{srcdir}/$file.log") or
+ error("failed to remove `$file.log'");
+
+ # Push the changes to the main repository.
+ system($darcs, 'push', '--quiet', '--repodir=' . $config{srcdir}, '--all')
+ and error('`darcs push\' failed');
+ # TODO: darcs send?
+
+ if ($conflicts) {
+ my $document = readfile("$config{srcdir}/$file");
+ # Try to leave everything in a consistent state.
+ # TODO: `yes | ...' needed? Doesn't seem so.
+ system($darcs, "revert", "--repodir=" . $config{srcdir}, "--all") and
+ warn("`darcs revert' failed.\n");
+ return $document;
+ } else {
+ return undef;
+ }
+ }
+
+ sub rcs_add ($) {
+ my $file = shift; # Relative to the repodir.
+
+ # Intermediate directories will be added automagically.
+ system($darcs, 'add', '--quiet', '--repodir=' . $config{srcdir},
+ '--boring', $file) and error('`darcs add\' failed');
+ }
+
+ sub rcs_recentchanges ($) {
+ warn('rcs_recentchanges() is not implemented');
+ return 'rcs_recentchanges() is not implemented';
+ }
+
+ sub rcs_notify () {
+ warn('rcs_notify() is not implemented');
+ }
+
+ sub rcs_getctime () {
+ warn('rcs_getctime() is not implemented');
+ }
+
+ 1
+"""]]
+
+This is my ([bma](bma@bmalee.eu)) darcs.pm - it's messy (my Perl isn't up to much) but seems to work. It uses just one repo, like the mercurial plugin (unlike the above version, which AIUI uses two).
+
+`rcs_commit()` uses backticks instead of `system()`, to prevent darcs' output being sent to the browser and mucking with the HTTP headers (`darcs record` has no --quiet option). And `rcs_recentchanges()` uses regexes rather than parsing darcs' XML output.
+
+[[toggle text="show" id="bma"]]
+[[toggleable id="bma" text="""
+
+ #!/usr/bin/perl
+
+ use warnings;
+ use strict;
+ use IkiWiki;
+ use Date::Parse;
+ use open qw{:utf8 :std};
+
+ package IkiWiki;
+
+ sub rcs_update () { #{{{
+ # Do nothing - there's nowhere to update *from*.
+ } #}}}
+
+ sub rcs_prepedit ($) { #{{{
+ } #}}}
+
+ sub rcs_commit ($$$;$$) { #{{{
+ my ($file, $message, $rcstoken, $user, $ipaddr) = @_;
+
+ # $user should probably be a name and an email address, by darcs
+ # convention.
+ if (defined $user) {
+ $user = possibly_foolish_untaint($user);
+ }
+ elsif (defined $ipaddr) {
+ $user = "Anonymous from $ipaddr";
+ }
+ else {
+ $user = "Anonymous";
+ }
+
+ $message = possibly_foolish_untaint($message);
+
+ # BUG: this outputs one line of text, and there's not a -q or --quiet
+ # option. Redirecting output to /dev/null works, but I still get the
+ # HTTP status and location headers displayed in the browser - is that
+ # darcs' fault or ikiwiki's?
+ # Doing it in backticks *works*, but I'm sure it could be done better.
+ my @cmdline = ("darcs", "record", "--repodir", "$config{srcdir}",
+ "-a", "-m", "$message", "--author", "$user", $file);
+ `darcs record --repodir "$config{srcdir}" -a -m "$message" --author "$user" $file`; # Return value? Output? Who needs 'em?
+ #if (system(@cmdline) != 0) {
+ # warn "'@cmdline' failed: $!";
+ #}
+
+ return undef; # success
+
+ sub rcs_add ($) { # {{{
+ my ($file) = @_;
+
+ my @cmdline = ("darcs", "add", "--repodir", "$config{srcdir}", "-a", "-q", "$file");
+ if (system(@cmdline) != 0) {
+ warn "'@cmdline' failed: $!";
+ }
+ } #}}}
+
+ sub rcs_recentchanges ($) { #{{{
+ # TODO: This is horrible code. It doesn't work perfectly, and uses regexes
+ # rather than parsing Darcs' XML output.
+ my $num=shift;
+ my @ret;
+
+ return unless -d "$config{srcdir}/_darcs";
+
+ my $changelog = `darcs changes --xml --summary --repodir "$config{srcdir}"`;
+ $changelog = join("", split(/\s*\n\s*/, $changelog));
+ my @changes = split(/<\/patch>.*?<patch/m, $changelog);
+
+
+ foreach my $change (@changes) {
+ $change =~ m/hash='(.*?)'/;
+ my $rev = $1;
+ $change =~ m/author='(.*?)'/;
+ my $user = $1."\n";
+ my $committype = "web";
+ if($user =~ m/&lt;/) {
+ # Author fields generated by darcs include an email address: look for the "<".
+ $committype = "darcs";
+ use HTML::Entities;
+ $user = decode_entities $user;
+ }
+ $change =~ m/local_date='(.*?)'/;
+ my $when = $1;
+ $when=time - str2time($when, 'UTC');
+ $change =~ m/<name>(.*?)<\/name>/g;
+ my @message = {line => $1};
+ foreach my $match ($change =~ m/<comment>(.*?)<\/comment>/gm) {
+ push @message, {line => $1};
+ }
+
+ my @pages;
+ foreach my $match ($change =~ m/<.*?_(file|directory)>(.*?)(<(added|removed)_lines.*\/>)*<\/.*?_(file|directory)>/g) {
+ # My perl-fu is weak. I'm probably going about this all wrong, anyway.
+ push @pages, {page => pagename($match)} if ( -f $config{srcdir}."/".$match || -d $config{srcdir}."/".$match) and not $match =~ m/^$/;
+ }
+ push @ret, { rev => $rev,
+ user => $user,
+ committype => $committype,
+ when => $when,
+ message => [@message],
+ pages => [@pages],
+ }
+ }
+ return @ret;
+ } #}}}
+
+ sub rcs_notify () { #{{{
+ # TODO
+ } #}}}
+
+ sub rcs_getctime ($) { #{{{
+ error gettext("getctime not implemented");
+ } #}}}
+
+ 1
+
+
+
+"""]]
+
+---
+
+Well, here's my version too. It only does getctime -- using a real XML parser, instead of regexp ugliness -- and maybe recentchanges, but that may be bitrotted, or maybe I never finished it, as I only need the getctime. As for actual commits, I have previously voiced my opinion, that this should be done by the plugin generating a patch bundle, and forwarding it to darcs in some way (`darcs apply` or even email to another host, possibly moderated), instead of the hacky direct modification of a working copy. It could also be faster to getctime in a batch. Just reading in all the changes the first time they're needed, might not be a big improvement in many cases, but if we got a batch request from ikiwiki, we could keep reaing the changes until all the files in this batch request have been met. --[[tuomov]]
+
+[[toggle text="show" id="tuomov"]]
+[[toggleable id="tuomov" text="""
+<pre>
+#!/usr/bin/perl
+# Stubs for no revision control.
+
+use warnings;
+use strict;
+use IkiWiki;
+
+package IkiWiki;
+
+sub rcs_update () {
+}
+
+sub rcs_prepedit ($) {
+ return ""
+}
+
+sub rcs_commit ($$$) {
+ return undef # success
+}
+
+sub rcs_add ($) {
+}
+
+sub rcs_recentchanges ($) {
+ my $num=shift;
+ my @ret;
+
+ eval q{use Date::Parse};
+ eval q{use XML::Simple};
+
+ my $repodir=$config{srcdir};
+
+ if (-d "$config{srcdir}/_darcs") {
+ my $child = open(LOG, "-|");
+ if (! $child) {
+ exec("darcs", "changes", "--xml",
+ "--repodir", "$repodir",
+ "--last", "$num")
+ || error("darcs changes failed to run");
+ }
+ my $data=<LOG>;
+ close LOG;
+
+ my $log = XMLin($data, ForceArray => 1);
+
+ foreach my $patch ($log->{patch}) {
+ my $date=$patch->{local_date};
+ my $hash=$patch->{hash};
+ my $when=concise(ago(time - str2time($date)));
+ my @pages;
+
+ my $child = open(SUMMARY, "-|");
+ if (! $child) {
+ exec("darcs", "annotate", "-s", "--xml",
+ "--match", "hash: $hash",
+ "--repodir", "$repodir")
+ || error("darcs annotate failed to run");
+ }
+ my $data=<SUMMARY>;
+ close SUMMARY;
+
+ my $summary = XMLin("<lame>$data</lame>", ForceArray => 1);
+
+ # TODO: find @pages
+
+ push @ret, {
+ #rev => $rev,
+ user => $patch->{author},
+ #committype => $committype,
+ when => $when,
+ #message => [@message],
+ pages => [@pages],
+ }; # if @pages;
+ return @ret if @ret >= $num;
+ }
+ }
+
+ return @ret;
+}
+
+sub rcs_notify () {
+}
+
+sub rcs_getctime ($) {
+ my $file=shift;
+
+ eval q{use Date::Parse};
+ eval q{use XML::Simple};
+ local $/=undef;
+
+ # Sigh... doing things the hard way again
+ my $repodir=$config{srcdir};
+
+ my $filer=substr($file, length($repodir));
+ $filer =~ s:^[/]+::;
+
+ my $child = open(LOG, "-|");
+ if (! $child) {
+ exec("darcs", "changes", "--xml", "--reverse",
+ "--repodir", "$repodir", "$filer")
+ || error("darcs changes $filer failed to run");
+ }
+
+ my $data=<LOG>;
+ close LOG;
+
+ my $log = XMLin($data, ForceArray => 1);
+
+ my $datestr=$log->{patch}[0]->{local_date};
+
+ if (! defined $datestr) {
+ warn "failed to get ctime for $filer";
+ return 0;
+ }
+
+ my $date=str2time($datestr);
+
+ debug("found ctime ".localtime($date)." for $file");
+
+ return $date;
+}
+
+1
+</pre>
+"""]]
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