From 08f6032344e060bd54285c449b2c1e99ad8d1591 Mon Sep 17 00:00:00 2001
From: Dobrica Pavlinusic <dpavlin@rot13.org>
Date: Mon, 22 Nov 2010 22:11:46 +0100
Subject: [PATCH] execute shell commands with trigger

---
 couchdb-trigger.pl | 29 ++++++++++++++++++++++++++---
 1 file changed, 26 insertions(+), 3 deletions(-)

diff --git a/couchdb-trigger.pl b/couchdb-trigger.pl
index 5f02e0f..d39f007 100755
--- a/couchdb-trigger.pl
+++ b/couchdb-trigger.pl
@@ -1,6 +1,14 @@
 #!/usr/bin/perl
 
+# back-end trigger server for CouchDB monitoring changes feed:
+#
 # http://wiki.apache.org/couchdb/HTTP_database_API#Changes
+#
+# implements state machine using document which you cen put with:
+#
+# curl -X PUT http://localhost:5984/monitor/df -d '{"trigger":{"command":"df -P","format":"table"}}'
+#
+# DEFAULT TRIGGER EXECUTE SHELL COMMANDS. IT IS NOT SECURE IF YOUR COUCHDB ISN'T SECURE!
 
 use warnings;
 use strict;
@@ -9,8 +17,23 @@ use lib 'common/mojo/lib';
 
 use Mojo::Client;
 use Mojo::JSON;
+use Time::HiRes qw(time);
 
 my $url = 'http://localhost:5984/monitor';
+
+sub _trigger {
+	my $trigger = $_[0]->{trigger};
+	if ( my $command = $trigger->{command} ) {
+		# FIXME SECURITY HOLE
+		my $output = $trigger->{output} = `$command`;
+
+		$trigger->{output} =
+			[ map { [ split (/\s+/,$_) ] } split(/\n/,$output) ]
+			if $trigger->{format} =~ m/table/i;
+	}
+	return $trigger;
+}
+
 my $seq = 0;
 
 my $client = Mojo::Client->new;
@@ -72,11 +95,11 @@ while( ! $error ) {
 							} else {
 								my $res = $tx->res->json;
 								$change->{doc}->{_rev} = $res->{rev};
-								debug "TRIGGER execute ", $change->{doc};
 
-								# FIXME trigger logic?
+								debug "TRIGGER execute ", $change->{doc};
+								_trigger( $change->{doc} );
 
-								push @{ $trigger->{active} }, time(); # timestamp step
+								push @{ $trigger->{active} }, time(), 0; # last timestamp
 
 								$client->put( "$url/$id" => $json->encode( $change->{doc} ) => sub {
 									my ($client,$tx) = @_;
-- 
2.20.1