From 506ebf13c6e965ea4392151ddc8009b69a4a6f80 Mon Sep 17 00:00:00 2001
From: Pragmatic Software <pragma78@gmail.com>
Date: Thu, 14 May 2020 16:57:34 -0700
Subject: [PATCH] DualIndexHashObject can now enqueue saves to prevent
 repeated-save thrashing

---
 PBot/DualIndexHashObject.pm | 39 +++++++++++++++++++++++++------------
 PBot/PBot.pm                |  7 +++++++
 2 files changed, 34 insertions(+), 12 deletions(-)

diff --git a/PBot/DualIndexHashObject.pm b/PBot/DualIndexHashObject.pm
index 81873503..48ed47b8 100644
--- a/PBot/DualIndexHashObject.pm
+++ b/PBot/DualIndexHashObject.pm
@@ -36,6 +36,7 @@ sub initialize {
     my ($self, %conf) = @_;
     $self->{name}     = $conf{name}     // 'Dual Index hash object';
     $self->{filename} = $conf{filename} // Carp::carp("Missing filename to DualIndexHashObject, will not be able to save to or load from file.");
+    $self->{save_queue_timeout} = $conf{save_queue_timeout} // 0;
     $self->{hash}     = {};
 }
 
@@ -107,20 +108,34 @@ sub save {
         return;
     }
 
-    $self->{pbot}->{logger}->log("Saving $self->{name} to $filename\n");
+    my $subref = sub {
+        $self->{pbot}->{logger}->log("Saving $self->{name} to $filename\n");
 
-    if (not $self->get_data('$metadata$', '$metadata$', 'update_version')) {
-        $self->add('$metadata$', '$metadata$', { update_version => PBot::VERSION::BUILD_REVISION });
+        if (not $self->get_data('$metadata$', '$metadata$', 'update_version')) {
+            $self->add('$metadata$', '$metadata$', { update_version => PBot::VERSION::BUILD_REVISION });
+        }
+
+        $self->set('$metadata$', '$metadata$', 'name', $self->{name}, 1);
+
+        my $json      = JSON->new;
+        my $json_text = $json->pretty->canonical->utf8->encode($self->{hash});
+
+        open(FILE, "> $filename") or die "Couldn't open $filename: $!\n";
+        print FILE "$json_text\n";
+        close FILE;
+    };
+
+    if ($self->{save_queue_timeout}) {
+        # enqueue the save to prevent save-thrashing
+        $self->{pbot}->{timer}->replace_subref_or_enqueue_event(
+            $subref,
+            $self->{save_queue_timeout},
+            "save $self->{name}",
+        );
+    } else {
+        # execute it right now
+        $subref->();
     }
-
-    $self->set('$metadata$', '$metadata$', 'name', $self->{name}, 1);
-
-    my $json      = JSON->new;
-    my $json_text = $json->pretty->canonical->utf8->encode($self->{hash});
-
-    open(FILE, "> $filename") or die "Couldn't open $filename: $!\n";
-    print FILE "$json_text\n";
-    close FILE;
 }
 
 sub clear {
diff --git a/PBot/PBot.pm b/PBot/PBot.pm
index 57c03f6b..68ec9bb4 100644
--- a/PBot/PBot.pm
+++ b/PBot/PBot.pm
@@ -258,6 +258,13 @@ sub initialize {
 
     # give botowner all capabilities
     $self->{capabilities}->rebuild_botowner_capabilities();
+
+    # flush all pending save events to disk at exit
+    $self->{atexit}->register(sub {
+            $self->{pbot}->{timer}->execute_and_dequeue_event('save *');
+            return;
+        }
+    );
 }
 
 sub random_nick {