1 files changed, 51 insertions, 0 deletions
diff --git a/scd4x.pl b/scd4x.pl
new file mode 100755
index 0000000..aae5919
--- /dev/null
+++ b/scd4x.pl
@@ -0,0 +1,51 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+use English;
+use POSIX;
+use JSON;
+use Net::MQTT::Simple;
+
+my $file = shift;
+my $host = shift;
+
+my $json = JSON->new->allow_nonref;
+my $mqtt;
+
+my $values;
+my $pvalues;
+my $serial;
+
+sub read_json_file {
+	my $filename = shift;
+	my $content;
+
+	open FILE, '<', $filename or die "read $filename: $!";
+	{ local $/; undef $/; $content = <FILE> }
+	close FILE;
+
+	return $json->decode($content);
+}
+
+if (defined($host)) {
+	$mqtt = Net::MQTT::Simple->new($host) or die "mqtt init (server $host)"
+}
+
+for (;;) {
+	$values = read_json_file($file);
+	$serial = $values->{'serial'};
+	for my $key ('co2', 'temperature', 'humidity') {
+		next if defined($pvalues->{$key}) and $pvalues->{$key} eq $values->{$key};
+		my $topic = "sensors/" . $key . "/scd4x/" . $serial;
+		if (defined($mqtt)) {
+			$mqtt->retain( $topic => $values->{$key} );
+		} else {
+			my $ts = POSIX::ctime(time());
+			chomp($ts);
+			printf("[%s] %-40s: %s\n",
+			       $ts, $topic, $values->{$key});
+		}
+	}
+	$pvalues = $values;
+	sleep 60;
+}