# Copyright (C) 2016-2018 all contributors
# License: AGPL-3.0+
# Wrap a pipe or file for PSGI streaming response bodies and calls the
# end callback when the object goes out-of-scope.
# This depends on rpipe being _blocking_ on getline.
#
# public-inbox-httpd favors "getline" response bodies to take a
# "pull"-based approach to feeding slow clients (as opposed to a
# more common "push" model)
package PublicInbox::GetlineBody;
use strict;
use warnings;
sub new {
my ($class, $rpipe, $end, $buf, $filter) = @_;
bless {
rpipe => $rpipe,
end => $end,
buf => $buf,
filter => $filter || 0,
}, $class;
}
# close should always be called after getline returns undef,
# but a client aborting a connection can ruin our day; so lets
# hope our underlying PSGI server does not leak references, here.
sub DESTROY { $_[0]->close }
sub getline {
my ($self) = @_;
my $filter = $self->{filter};
return if $filter == -1; # last call was EOF
my $buf = delete $self->{buf}; # initial buffer
$buf = $self->{rpipe}->getline unless defined $buf;
$self->{filter} = -1 unless defined $buf; # set EOF for next call
$filter ? $filter->($buf) : $buf;
}
sub close {
my ($self) = @_;
my $rpipe = delete $self->{rpipe};
close $rpipe if $rpipe;
my $end = delete $self->{end};
$end->() if $end;
}
1;