[PATCH 05/13] support publicinbox.cgitrc directive

[Eric Wong <e@80x24.org>]

We can save admins the trouble of declaring [coderepo "..."]
sections in the public-inbox config by parsing the cgitrc
directly.

Macro expansion (e.g. $HTTP_HOST) expansion is not supported,
yet; but may be in the future.
---
 Documentation/public-inbox-config.pod | 15 +++++++-
 lib/PublicInbox/Config.pm             | 54 +++++++++++++++++++++++++--
 lib/PublicInbox/Git.pm                | 13 ++++++-
 lib/PublicInbox/SolverGit.pm          |  5 ++-
 4 files changed, 77 insertions(+), 10 deletions(-)

diff --git a/Documentation/public-inbox-config.pod b/Documentation/public-inbox-config.pod
index 27d27e4..5ee93e2 100644
--- a/Documentation/public-inbox-config.pod
+++ b/Documentation/public-inbox-config.pod
@@ -188,16 +188,27 @@ be treated as the default value.
 
 Default: 25
 
-=item coderepo.<name>.dir
+=item coderepo.<nick>.dir
 
 The path to a git repository for "publicinbox.<name>.coderepo"
 
-=item coderepo.<name>.cgitUrl
+=item coderepo.<nick>.cgitUrl
 
 The URL of the cgit instance associated with the coderepo.
 
 Default: none
 
+=item publicinbox.cgitrc
+
+A path to a L<cgitrc(5)> file.  "repo.url" directives in the cgitrc
+will be mapped to the nickname of a coderepo (without trailing slash),
+and "repo.path" directives map to "coderepo.<nick>.dir".
+Use of this directive allows admins of existing cgit installations
+to skip declaring coderepo sections and map inboxes directly to
+code repositories known to cgit.
+
+Macro expansion (e.g. C<$HTTP_HOST>) is not yet supported.
+
 =back
 
 =head2 NAMED LIMITER (PSGI)
diff --git a/lib/PublicInbox/Config.pm b/lib/PublicInbox/Config.pm
index da443e5..490b4c4 100644
--- a/lib/PublicInbox/Config.pm
+++ b/lib/PublicInbox/Config.pm
@@ -196,15 +196,59 @@ sub valid_inbox_name ($) {
 	1;
 }
 
+sub cgit_repo_merge ($$) {
+	my ($self, $repo) = @_;
+	# $repo = { url => 'foo.git', path => '/path/to/foo.git' }
+	my $nick = $repo->{url};
+	$self->{"coderepo.$nick.dir"} ||= $repo->{path};
+	$self->{"coderepo.$nick.cgiturl"} ||= $nick;
+}
+
+sub parse_cgitrc {
+	my ($self, $cgitrc, $nesting) = @_;
+
+	# same limit as cgit/configfile.c::parse_configfile
+	return if $nesting > 8;
+
+	open my $fh, '<', $cgitrc or do {
+		warn "failed to open cgitrc=$cgitrc: $!\n";
+		return;
+	};
+
+	# FIXME: this doesn't support macro expansion via $VARS, yet
+	my $repo;
+	foreach (<$fh>) {
+		chomp;
+		if (m!\Arepo\.url=(.+?)/*\z!) {
+			my $nick = $1;
+			cgit_repo_merge($self, $repo) if $repo;
+			$repo = { url => $nick };
+		} elsif (m!\Arepo\.path=(.+)\z!) {
+			if (defined $repo) {
+				$repo->{path} = $1;
+			} else {
+				warn "$_ without repo.url\n";
+			}
+		} elsif (m!\Ainclude=(.+)\z!) {
+			parse_cgitrc($self, $1, $nesting + 1);
+		}
+	}
+	cgit_repo_merge($self, $repo) if $repo;
+}
+
 # parse a code repo
 # Only git is supported at the moment, but SVN and Hg are possibilities
 sub _fill_code_repo {
 	my ($self, $nick) = @_;
 	my $pfx = "coderepo.$nick";
 
+	# TODO: support gitweb and other repository viewers?
+	if (defined(my $cgitrc = delete $self->{'publicinbox.cgitrc'})) {
+		parse_cgitrc($self, $cgitrc, 0);
+	}
 	my $dir = $self->{"$pfx.dir"}; # aka "GIT_DIR"
 	unless (defined $dir) {
-		warn "$pfx.repodir unset";
+		warn "$pfx.dir unset";
 		return;
 	}
 
@@ -225,8 +269,6 @@ sub _fill_code_repo {
 			} @$cgits;
 		}
 	}
-	# TODO: support gitweb and other repository viewers?
-	# TODO: parse cgitrc
 
 	$git;
 }
@@ -291,7 +333,11 @@ sub _fill {
 		my $code_repos = $self->{-code_repos};
 		my $repo_objs = $rv->{-repo_objs} = [];
 		foreach my $nick (@$ibx_code_repos) {
-			valid_inbox_name($nick) or next;
+			my @parts = split(m!/!, $nick);
+			my $valid = 0;
+			$valid += valid_inbox_name($_) foreach (@parts);
+			$valid == scalar(@parts) or next;
+
 			my $repo = $code_repos->{$nick} ||=
 						_fill_code_repo($self, $nick);
 			push @$repo_objs, $repo if $repo;
diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index 265c3fb..8a96e10 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -288,10 +288,19 @@ sub src_blob_url {
 	local_nick($self);
 }
 
+sub host_prefix_url ($$) {
+	my ($env, $url) = @_;
+	return $url if index($url, '//') >= 0;
+	my $scheme = $env->{'psgi.url_scheme'};
+	my $host_port = $env->{HTTP_HOST} ||
+		"$env->{SERVER_NAME}:$env->{SERVER_PORT}";
+	"$scheme://$host_port". ($env->{SCRIPT_NAME} || '/') . $url;
+}
+
 sub pub_urls {
-	my ($self) = @_;
+	my ($self, $env) = @_;
 	if (my $urls = $self->{cgit_url}) {
-		return @$urls;
+		return map { host_prefix_url($env, $_) } @$urls;
 	}
 	local_nick($self);
 }
diff --git a/lib/PublicInbox/SolverGit.pm b/lib/PublicInbox/SolverGit.pm
index cd0f94a..3841c56 100644
--- a/lib/PublicInbox/SolverGit.pm
+++ b/lib/PublicInbox/SolverGit.pm
@@ -85,7 +85,8 @@ sub solve_existing ($$) {
 		# push @ambiguous, [ $git, @oids ];
 
 		dbg($self, "`$oid_b' ambiguous in " .
-				join("\n\t", $git->pub_urls) . "\n" .
+				join("\n\t", $git->pub_urls($self->{psgi_env}))
+                                . "\n" .
 				join('', map { "$_ blob\n" } @oids));
 	}
 	scalar(@ambiguous) ? \@ambiguous : undef;
@@ -483,7 +484,7 @@ sub resolve_patch ($$) {
 	if (my $existing = solve_existing($self, $want)) {
 		my ($found_git, undef, $type, undef) = @$existing;
 		dbg($self, "found $cur_want in " .
-			join("\n", $found_git->pub_urls));
+			join("\n", $found_git->pub_urls($self->{psgi_env})));
 
 		if ($cur_want eq $self->{oid_want} || $type ne 'blob') {
 			eval { delete($self->{user_cb})->($existing) };
-- 
EW