sensor graphs for homepage

[svn42.git] / sensor_graph / get_sensor_light.pl
diff --git a/sensor_graph/get_sensor_light.pl b/sensor_graph/get_sensor_light.pl

new file mode 100644 (file)

index 0000000..85fe638
--- /dev/null
+++ b/sensor_graph/get_sensor_light.pl
@@ -0,0 +1,71 @@
+#!/usr/bin/perl -w
+#
+#
+
+use strict;
+use utf8;
+require LWP::UserAgent;
+my $ua = LWP::UserAgent->new(env_proxy => 1,
+                              keep_alive => 1,
+                              timeout => 30,
+                             );
+use HTTP::Cookies;
+use LWP;
+$ua->cookie_jar({});
+
+###############
+$sensor::url_refresh = "http://slug.realraum.at/cgi-bin/sensor-light.cgi";
+$sensor::url_image = "http://slug.realraum.at/light0.png";
+$sensor::localpath = "/tmp/light0.png";
+$sensor::mintime = 0.0015;
+###############
+
+sub output_saved_image
+{
+  return 0 if ( not -e $sensor::localpath);
+  my $fh;  
+  print STDOUT "Content-type: image/png\n\n";
+  open($fh,"<$sensor::localpath") or exit;
+  while (<$fh>) {print $_};
+  close($fh);
+  return 1;
+}
+
+sub output_remote_image_and_save
+{
+  my $response;
+  $response = $ua->get($sensor::url_refresh);
+  return 0 unless (defined $response);
+  $response = $ua->get($sensor::url_image);
+  if (defined $response and $response->content =~ /^\x89PNG/)
+  {
+    my $fh;
+    open($fh,">$sensor::localpath");
+    print $fh $response->content;
+    close($fh);
+    print STDOUT "Content-type: image/png\n\n";
+    print $response->content;
+    $response->clear;
+    return 1;
+  }
+  return 0;
+}
+
+sub output_error
+{
+  print STDOUT "Status: 404 Not Found\n";
+  print STDOUT "Content-type: text/html\n\n";
+  print STDOUT "<html><body><h1>Sorry</h1><h2>The picture you requested could not be found</h2></body></html>\n"; 
+  return 1;
+}
+
+if (-e $sensor::localpath and -M $sensor::localpath < $sensor::mintime)
+{
+  exit if (&output_saved_image);
+}
+else
+{
+  exit if (&output_remote_image_and_save);
+  exit if (&output_saved_image);
+}
+&output_error;