[pmg-devel] [PATCH pmg-api v4 5/5] fix #2709: ruledb: match-field: optionally restrict to top mime-part

[Stoiko Ivanov]

On Fri, 21 Feb 2025 11:10:36 +0100
Dominik Csapak <d.csapak at proxmox.com> wrote:

> an alternative to this could be that we don't traverse entities if they
> are a 'message/rfc822' ? that way we could still match fields from
> individual parts, just not in nested messages.

Currently don't see an example where any field I'd want to match in
the first-part headers only (From/To/Subject/....) would occur anywhere in
a attachment, which is not 'message/rfc822'.
OTOH if I want to match fields of non-top-MIME-Parts (usually attachments,
alternatives/.. - Content-Type/Disposition/Encoding) I think I would not
want to restrict the match to not include attachments of attached e-mails?

I think we can wait for the use-case for this to come up in the community
- and then change the checkbox to a combobox (default, top-only,
ignore-message/rfc822) - What do you think?


> 
> But I think this patch is still fine since we document the
> match field for mail headers and those (should) only
> appear in the top-level part anyway..
> 
> On 2/20/25 21:13, Stoiko Ivanov wrote:
> > The current Match Field (header) what-objects always traverse each
> > mime-part of a mail.
> > This can be inconvenient, and causes unexpected matches when you
> > forward a message as attachment(message/rfc822).
> > 
> > following the patches for adding a Disclaimer on top of a mail from an
> > implementation point of view, this simply adds an optional
> > top-level-only attribute for the MatchField object, which is disabled
> > by default for backwards-compatibility.
> > 
> > Signed-off-by: Stoiko Ivanov <s.ivanov at proxmox.com>
> > ---
> >   src/PMG/RuleDB/ContentTypeFilter.pm |  2 +-
> >   src/PMG/RuleDB/MatchField.pm        | 47 +++++++++++++++++++++++++++--
> >   2 files changed, 45 insertions(+), 4 deletions(-)
> > 
> > diff --git a/src/PMG/RuleDB/ContentTypeFilter.pm b/src/PMG/RuleDB/ContentTypeFilter.pm
> > index e44bf3c..6818de1 100644
> > --- a/src/PMG/RuleDB/ContentTypeFilter.pm
> > +++ b/src/PMG/RuleDB/ContentTypeFilter.pm
> > @@ -35,7 +35,7 @@ sub new {
> >   	$fvalue = $nt;
> >       }
> >   
> > -    my $self = $class->SUPER::new('content-type', $fvalue, $ogroup);
> > +    my $self = $class->SUPER::new('content-type', $fvalue, $ogroup, undef);
> >       $self->{only_content} = $only_content;
> >   
> >       return $self;
> > diff --git a/src/PMG/RuleDB/MatchField.pm b/src/PMG/RuleDB/MatchField.pm
> > index ee1851a..f6787e8 100644
> > --- a/src/PMG/RuleDB/MatchField.pm
> > +++ b/src/PMG/RuleDB/MatchField.pm
> > @@ -27,7 +27,7 @@ sub otype_text {
> >   }
> >   
> >   sub new {
> > -    my ($type, $field, $field_value, $ogroup) = @_;
> > +    my ($type, $field, $field_value, $ogroup, $top_part_only) = @_;
> >   
> >       my $class = ref($type) || $type;
> >   
> > @@ -35,6 +35,7 @@ sub new {
> >   
> >       $self->{field} = $field;
> >       $self->{field_value} = $field_value;
> > +    $self->{top_part_only} = $top_part_only;
> >   
> >       return $self;
> >   }
> > @@ -54,12 +55,28 @@ sub load_attr {
> >       my $decoded_field_value = PMG::Utils::try_decode_utf8($field_value);
> >       # use known constructor, bless afterwards (because sub class can have constructor
> >       # with other parameter signature).
> > -    my $obj =  PMG::RuleDB::MatchField->new($field, $decoded_field_value, $ogroup);
> > +    my $obj =  PMG::RuleDB::MatchField->new($field, $decoded_field_value, $ogroup, undef);
> >       bless $obj, $class;
> >   
> > +    my $sth = $ruledb->{dbh}->prepare(
> > +	"SELECT * FROM Attribut WHERE Object_ID = ?");
> > +
> > +    $sth->execute($id);
> > +
> > +    $obj->{top_part_only} = 0;
> > +
> > +    while (my $ref = $sth->fetchrow_hashref()) {
> > +	if ($ref->{name} eq 'top_part_only') {
> > +	    $obj->{top_part_only} = $ref->{value};
> > +	}
> > +    }
> > +
> > +    $sth->finish();
> > +
> >       $obj->{id} = $id;
> >   
> > -    $obj->{digest} = Digest::SHA::sha1_hex($id, $field, $field_value, $ogroup);
> > +    $obj->{digest} = Digest::SHA::sha1_hex(
> > +	$id, $field, $field_value, $ogroup, $obj->{top_part_only});
> >   
> >       return $obj;
> >   }
> > @@ -79,6 +96,9 @@ sub save {
> >   
> >       if (defined ($self->{id})) {
> >   	# update
> > +	$ruledb->{dbh}->do(
> > +	    "DELETE FROM Attribut WHERE Object_ID = ?",
> > +	    undef, $self->{id});
> >   
> >   	$ruledb->{dbh}->do(
> >   	    "UPDATE Object SET Value = ? WHERE ID = ?",
> > @@ -96,6 +116,12 @@ sub save {
> >   	$self->{id} = PMG::Utils::lastid($ruledb->{dbh}, 'object_id_seq');
> >       }
> >   
> > +    if (defined($self->{top_part_only})) {
> > +	$ruledb->{dbh}->do(
> > +	    "INSERT INTO Attribut (Value, Name, Object_ID) VALUES (?, 'top_part_only', ?)",
> > +	    undef, $self->{top_part_only}, $self->{id});
> > +    }
> > +
> >       return $self->{id};
> >   }
> >   
> > @@ -124,6 +150,8 @@ sub parse_entity {
> >   	}
> >       }
> >   
> > +    return $res if $self->{top_part_only};
> > +
> >       foreach my $part ($entity->parts)  {
> >   	if (my $match = $self->parse_entity($part)) {
> >   	    push @$res, @$match;
> > @@ -160,6 +188,12 @@ sub properties {
> >   	    type => 'string',
> >   	    maxLength => 1024,
> >   	},
> > +	'top-part-only' => {
> > +	    description => "only match the headers in the first MIME-Part",
> > +	    type => 'boolean',
> > +	    optional => 1,
> > +	    default => 0,
> > +	},
> >       };
> >   }
> >   
> > @@ -169,6 +203,7 @@ sub get {
> >       return {
> >   	field => $self->{field},
> >   	value => $self->{field_value},
> > +	'top-part-only' => $self->{top_part_only},
> >       };
> >   }
> >   
> > @@ -177,6 +212,12 @@ sub update {
> >   
> >       $self->{field_value} = $param->{value};
> >       $self->{field} = $param->{field};
> > +
> > +    if (defined($param->{'top-part-only'}) && $param->{'top-part-only'} == 1) {
> > +	$self->{top_part_only} = 1;
> > +    } else {
> > +	delete $self->{top_part_only};
> > +    }
> >   }
> >   
> >   1;  
> 
>