From 19e129a0cee26673b1aa9198ae52582a7307e15a Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Date: Sat, 11 Nov 2023 19:06:22 +0100
Subject: [PATCH] Log delay in the Slack WebSocket API.

---
 bin/ws.pl | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/bin/ws.pl b/bin/ws.pl
index 79394f3..0cf8e7b 100644
--- a/bin/ws.pl
+++ b/bin/ws.pl
@@ -69,10 +69,16 @@ sub ws_cb {
 
 	$connection->on(each_message => sub {
 		my ($conn, $message) = @_;
+		my $now = [Time::HiRes::gettimeofday];
 		print STDERR "Message: $message->{'body'}\n";
 		my $json = JSON::XS::decode_json($message->{'body'});
 		eval {
 			if (exists($json->{'payload'}{'event'})) {
+				if (exists($json->{'payload'}{'event'}{'event_ts'}) &&
+				    $json->{'payload'}{'event'}{'event_ts'} =~ /(\d+)\.(\d+)/) {
+					my $elapsed = Time::HiRes::tv_interval([$1, $2], $now);
+					printf STDERR "Message used %.1f ms to reach us.\n", 1e3 * $elapsed;
+				}
 				handle_event($json->{'payload'}{'event'});
 			}
 		};
-- 
2.39.2