[pmg-devel] [PATCH pmg-api] rulecache: sort rules additionally by id

[pmg-devel] [PATCH pmg-api] rulecache: sort rules additionally by id

[Stoiko Ivanov]

When more rules have the same priority currently their order is not
stable - postgres returns them in a stable way, based on their last
changetime - e.g. disabling and reenabling a rule puts it in the front
of evaluation. Sortin by id (the primary key) in addition should make
rule evaluation robust to such updates

While there is no guarantee of ordering (within the same priority)
unexpected changes in which rule fires can cause confusion (at least
it confused me quite a bit).

Reported-by: Mira Limbeck <m.limbeck@proxmox.com>
Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
---
With this applied I got stable ruleaction executions across rule-changes and
pmg-smtp-filter restarts, but would appreciate some additional test

 src/PMG/RuleCache.pm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/PMG/RuleCache.pm b/src/PMG/RuleCache.pm
index d35e9c1..ebce98e 100644
--- a/src/PMG/RuleCache.pm
+++ b/src/PMG/RuleCache.pm
@@ -37,7 +37,7 @@ sub new {
 	my $sth = $dbh->prepare(
 	    "SELECT ID, Name, Priority, Active, Direction FROM Rule " .
 	    "where Active > 0 " .
-	    "ORDER BY Priority DESC");
+	    "ORDER BY Priority, ID DESC");
 
 	$sth->execute();
 
-- 
2.30.2

Re: [pmg-devel] [PATCH pmg-api] rulecache: sort rules additionally by id

[Dominik Csapak]

On 11/30/22 14:20, Stoiko Ivanov wrote:
> When more rules have the same priority currently their order is not
> stable - postgres returns them in a stable way, based on their last
> changetime - e.g. disabling and reenabling a rule puts it in the front
> of evaluation. Sortin by id (the primary key) in addition should make
> rule evaluation robust to such updates
> 
> While there is no guarantee of ordering (within the same priority)
> unexpected changes in which rule fires can cause confusion (at least
> it confused me quite a bit).
> 
> Reported-by: Mira Limbeck <m.limbeck@proxmox.com>
> Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>
> ---
> With this applied I got stable ruleaction executions across rule-changes and
> pmg-smtp-filter restarts, but would appreciate some additional test
> 
>   src/PMG/RuleCache.pm | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/src/PMG/RuleCache.pm b/src/PMG/RuleCache.pm
> index d35e9c1..ebce98e 100644
> --- a/src/PMG/RuleCache.pm
> +++ b/src/PMG/RuleCache.pm
> @@ -37,7 +37,7 @@ sub new {
>   	my $sth = $dbh->prepare(
>   	    "SELECT ID, Name, Priority, Active, Direction FROM Rule " .
>   	    "where Active > 0 " .
> -	    "ORDER BY Priority DESC");
> +	    "ORDER BY Priority, ID DESC");

this sadly loses the 'DESC' ordering for the priority and all
rules are now loaded in the reverse order 🙃

>   
>   	$sth->execute();
>