travelynx/lib/Travelynx/Model/JourneyStatsCache.pm
2020-11-28 21:03:51 +01:00

100 lines
1.9 KiB
Perl
Executable file

package Travelynx::Model::JourneyStatsCache;
# Copyright (C) 2020 Daniel Friesel
#
# SPDX-License-Identifier: MIT
use strict;
use warnings;
use 5.020;
use utf8;
import JSON;
sub new {
my ( $class, %opt ) = @_;
return bless( \%opt, $class );
}
sub add {
my ( $self, %opt ) = @_;
my $db = $opt{db} // $self->{pg}->db;
eval {
$db->insert(
'journey_stats',
{
user_id => $opt{uid},
year => $opt{year},
month => $opt{month},
data => JSON->new->encode($opt{stats}),
}
);
};
if ( my $err = $@ ) {
if ( $err =~ m{duplicate key value violates unique constraint} )
{
# If a user opens the same history page several times in
# short succession, there is a race condition where several
# Mojolicious workers execute this helper, notice that there is
# no up-to-date history, compute it, and insert it using the
# statement above. This will lead to a uniqueness violation
# in each successive insert. However, this is harmless, and
# thus ignored.
}
else {
# Otherwise we probably have a problem.
die($@);
}
}
}
sub get {
my ( $self, %opt ) = @_;
my $db = $opt{db} // $self->{pg}->db;
my $stats = $db->select(
'journey_stats',
['data'],
{
user_id => $opt{uid},
year => $opt{year},
month => $opt{month}
}
)->expand->hash;
return $stats->{data};
}
# Statistics are partitioned by real_departure, which must be provided
# when calling this function e.g. after journey deletion or editing.
# If a joureny's real_departure has been edited, this function must be
# called twice: once with the old and once with the new value.
sub invalidate {
my ( $self, %opt ) = @_;
my $ts = $opt{ts};
my $db = $opt{db} // $self->{pg}->db;
my $uid = $opt{uid};
$db->delete(
'journey_stats',
{
user_id => $uid,
year => $ts->year,
month => $ts->month,
}
);
$db->delete(
'journey_stats',
{
user_id => $uid,
year => $ts->year,
month => 0,
}
);
}
1;