# Copyright (C) 2018-2020 all contributors
# License: AGPL-3.0+
# for XOVER, OVER in NNTP, and feeds/homepage/threads in PSGI
# Unlike Msgmap, this is an _UNSTABLE_ cache which can be
# tweaked/updated over time and rebuilt.
#
# Ghost messages (messages which are only referenced in References/In-Reply-To)
# are denoted by a negative NNTP article number.
package PublicInbox::OverIdx;
use strict;
use v5.10.1;
use parent qw(PublicInbox::Over);
use IO::Handle;
use DBI qw(:sql_types); # SQL_BLOB
use PublicInbox::MID qw/id_compress mids_for_index references/;
use PublicInbox::Smsg qw(subject_normalized);
use Compress::Zlib qw(compress);
use Carp qw(croak);
sub dbh_new {
my ($self) = @_;
my $dbh = $self->SUPER::dbh_new($self->{-no_fsync} ? 2 : 1);
# 80000 pages (80MiB on SQLite <3.12.0, 320MiB on 3.12.0+)
# was found to be good in 2018 during the large LKML import
# at the time. This ought to be configurable based on HW
# and inbox size; I suspect it's overkill for many inboxes.
$dbh->do('PRAGMA cache_size = 80000');
create_tables($dbh);
$dbh;
}
sub new {
my ($class, $f) = @_;
my $self = $class->SUPER::new($f);
$self->{min_tid} = 0;
$self;
}
sub get_counter ($$) {
my ($dbh, $key) = @_;
my $sth = $dbh->prepare_cached(<<'', undef, 1);
SELECT val FROM counter WHERE key = ? LIMIT 1
$sth->execute($key);
$sth->fetchrow_array;
}
sub adj_counter ($$$) {
my ($self, $key, $op) = @_;
my $dbh = $self->{dbh};
my $sth = $dbh->prepare_cached(<<"");
UPDATE counter SET val = val $op 1 WHERE key = ?
$sth->execute($key);
get_counter($dbh, $key);
}
sub next_tid { adj_counter($_[0], 'thread', '+') }
sub next_ghost_num { adj_counter($_[0], 'ghost', '-') }
sub id_for ($$$$$) {
my ($self, $tbl, $id_col, $val_col, $val) = @_;
my $dbh = $self->{dbh};
my $in = $dbh->prepare_cached(<<"")->execute($val);
INSERT OR IGNORE INTO $tbl ($val_col) VALUES (?)
if ($in == 0) {
my $sth = $dbh->prepare_cached(<<"", undef, 1);
SELECT $id_col FROM $tbl WHERE $val_col = ? LIMIT 1
$sth->execute($val);
$sth->fetchrow_array;
} else {
$dbh->last_insert_id(undef, undef, $tbl, $id_col);
}
}
sub sid {
my ($self, $path) = @_;
return unless defined $path && $path ne '';
id_for($self, 'subject', 'sid', 'path' => $path);
}
sub mid2id {
my ($self, $mid) = @_;
id_for($self, 'msgid', 'id', 'mid' => $mid);
}
sub delete_by_num {
my ($self, $num, $tid_ref) = @_;
my $dbh = $self->{dbh};
if ($tid_ref) {
my $sth = $dbh->prepare_cached(<<'', undef, 1);
SELECT tid FROM over WHERE num = ? LIMIT 1
$sth->execute($num);
$$tid_ref = $sth->fetchrow_array; # may be undef
}
foreach (qw(over id2num)) {
$dbh->prepare_cached(<<"")->execute($num);
DELETE FROM $_ WHERE num = ?
}
}
# this includes ghosts
sub each_by_mid {
my ($self, $mid, $cols, $cb, @arg) = @_;
my $dbh = $self->{dbh};
=over
I originally wanted to stuff everything into a single query:
SELECT over.* FROM over
LEFT JOIN id2num ON over.num = id2num.num
LEFT JOIN msgid ON msgid.id = id2num.id
WHERE msgid.mid = ? AND over.num >= ?
ORDER BY over.num ASC
LIMIT 1000
But it's faster broken out (and we're always in a
transaction for subroutines in this file)
=cut
my $sth = $dbh->prepare_cached(<<'', undef, 1);
SELECT id FROM msgid WHERE mid = ? LIMIT 1
$sth->execute($mid);
my $id = $sth->fetchrow_array;
defined $id or return;
push(@$cols, 'num');
$cols = join(',', map { $_ } @$cols);
my $lim = 10;
my $prev = get_counter($dbh, 'ghost');
while (1) {
$sth = $dbh->prepare_cached(<<"", undef, 1);
SELECT num FROM id2num WHERE id = ? AND num >= ?
ORDER BY num ASC
LIMIT $lim
$sth->execute($id, $prev);
my $nums = $sth->fetchall_arrayref;
my $nr = scalar(@$nums) or return;
$prev = $nums->[-1]->[0];
$sth = $dbh->prepare_cached(<<"", undef, 1);
SELECT $cols FROM over WHERE over.num = ? LIMIT 1
foreach (@$nums) {
$sth->execute($_->[0]);
my $smsg = $sth->fetchrow_hashref;
$smsg = PublicInbox::Over::load_from_row($smsg);
$cb->($self, $smsg, @arg) or return;
}
return if $nr != $lim;
}
}
sub _resolve_mid_to_tid {
my ($self, $smsg, $tid) = @_;
my $cur_tid = $smsg->{tid};
if (defined $$tid) {
merge_threads($self, $$tid, $cur_tid);
} elsif ($cur_tid > $self->{min_tid}) {
$$tid = $cur_tid;
} else { # rethreading, queue up dead ghosts
$$tid = next_tid($self);
my $num = $smsg->{num};
push(@{$self->{-ghosts_to_delete}}, $num) if $num < 0;
}
1;
}
# this will create a ghost as necessary
sub resolve_mid_to_tid {
my ($self, $mid) = @_;
my $tid;
each_by_mid($self, $mid, ['tid'], \&_resolve_mid_to_tid, \$tid);
if (my $del = delete $self->{-ghosts_to_delete}) {
delete_by_num($self, $_) for @$del;
}
$tid // do { # create a new ghost
my $id = mid2id($self, $mid);
my $num = next_ghost_num($self);
$num < 0 or die "ghost num is non-negative: $num\n";
$tid = next_tid($self);
my $dbh = $self->{dbh};
$dbh->prepare_cached(<<'')->execute($num, $tid);
INSERT INTO over (num, tid) VALUES (?,?)
$dbh->prepare_cached(<<'')->execute($id, $num);
INSERT INTO id2num (id, num) VALUES (?,?)
$tid;
};
}
sub merge_threads {
my ($self, $winner_tid, $loser_tid) = @_;
return if $winner_tid == $loser_tid;
my $dbh = $self->{dbh};
$dbh->prepare_cached(<<'')->execute($winner_tid, $loser_tid);
UPDATE over SET tid = ? WHERE tid = ?
}
sub link_refs {
my ($self, $refs, $old_tid) = @_;
my $tid;
if (@$refs) {
# first ref *should* be the thread root,
# but we can never trust clients to do the right thing
my $ref = $refs->[0];
$tid = resolve_mid_to_tid($self, $ref);
merge_threads($self, $tid, $old_tid) if defined $old_tid;
# the rest of the refs should point to this tid:
foreach my $i (1..$#$refs) {
$ref = $refs->[$i];
my $ptid = resolve_mid_to_tid($self, $ref);
merge_threads($self, $tid, $ptid);
}
} else {
$tid = $old_tid // next_tid($self);
}
$tid;
}
sub parse_references ($$$) {
my ($smsg, $hdr, $mids) = @_;
my $refs = references($hdr);
push(@$refs, @$mids) if scalar(@$mids) > 1;
return $refs if scalar(@$refs) == 0;
# prevent circular references here:
my %seen = ( $smsg->{mid} => 1 );
my @keep;
foreach my $ref (@$refs) {
if (length($ref) > PublicInbox::MID::MAX_MID_SIZE) {
warn "References: <$ref> too long, ignoring\n";
next;
}
push(@keep, $ref) unless $seen{$ref}++;
}
$smsg->{references} = '<'.join('> <', @keep).'>' if @keep;
\@keep;
}
# normalize subjects so they are suitable as pathnames for URLs
# XXX: consider for removal
sub subject_path ($) {
my ($subj) = @_;
$subj = subject_normalized($subj);
$subj =~ s![^a-zA-Z0-9_\.~/\-]+!_!g;
lc($subj);
}
sub add_overview {
my ($self, $eml, $smsg) = @_;
$smsg->{lines} = $eml->body_raw =~ tr!\n!\n!;
my $mids = mids_for_index($eml);
my $refs = parse_references($smsg, $eml, $mids);
my $subj = $smsg->{subject};
my $xpath;
if ($subj ne '') {
$xpath = subject_path($subj);
$xpath = id_compress($xpath);
}
my $dd = $smsg->to_doc_data;
utf8::encode($dd);
$dd = compress($dd);
add_over($self, $smsg, $mids, $refs, $xpath, $dd);
}
sub _add_over {
my ($self, $smsg, $mid, $refs, $old_tid, $v) = @_;
my $cur_tid = $smsg->{tid};
my $n = $smsg->{num};
die "num must not be zero for $mid" if !$n;
my $cur_valid = $cur_tid > $self->{min_tid};
if ($n > 0) { # regular mail
if ($cur_valid) {
$$old_tid //= $cur_tid;
merge_threads($self, $$old_tid, $cur_tid);
} else {
$$old_tid //= next_tid($self);
}
} elsif ($n < 0) { # ghost
$$old_tid //= $cur_valid ? $cur_tid : next_tid($self);
link_refs($self, $refs, $$old_tid);
delete_by_num($self, $n);
$$v++;
}
1;
}
sub add_over {
my ($self, $smsg, $mids, $refs, $xpath, $ddd) = @_;
my $old_tid;
my $vivified = 0;
my $num = $smsg->{num};
begin_lazy($self);
delete_by_num($self, $num, \$old_tid);
$old_tid = undef if ($old_tid // 0) <= $self->{min_tid};
foreach my $mid (@$mids) {
my $v = 0;
each_by_mid($self, $mid, ['tid'], \&_add_over,
$mid, $refs, \$old_tid, \$v);
$v > 1 and warn "BUG: vivified multiple ($v) ghosts for $mid\n";
$vivified += $v;
}
$smsg->{tid} = $vivified ? $old_tid : link_refs($self, $refs, $old_tid);
$smsg->{sid} = sid($self, $xpath);
my $dbh = $self->{dbh};
my $sth = $dbh->prepare_cached(<<'');
INSERT INTO over (num, tid, sid, ts, ds, ddd)
VALUES (?,?,?,?,?,?)
my $nc = 1;
$sth->bind_param($nc, $num);
$sth->bind_param(++$nc, $smsg->{$_}) for (qw(tid sid ts ds));
$sth->bind_param(++$nc, $ddd, SQL_BLOB);
$sth->execute;
$sth = $dbh->prepare_cached(<<'');
INSERT INTO id2num (id, num) VALUES (?,?)
foreach my $mid (@$mids) {
my $id = mid2id($self, $mid);
$sth->execute($id, $num);
}
}
sub _remove_oid {
my ($self, $smsg, $oid, $removed) = @_;
if (!defined($oid) || $smsg->{blob} eq $oid) {
delete_by_num($self, $smsg->{num});
push @$removed, $smsg->{num};
}
1;
}
# returns number of removed messages in scalar context,
# array of removed article numbers in array context.
# $oid may be undef to match only on $mid
sub remove_oid {
my ($self, $oid, $mid) = @_;
my $removed = [];
begin_lazy($self);
each_by_mid($self, $mid, ['ddd'], \&_remove_oid, $oid, $removed);
@$removed;
}
sub _num_mid0_for_oid {
my ($self, $smsg, $oid, $res) = @_;
my $blob = $smsg->{blob};
return 1 if (!defined($blob) || $blob ne $oid); # continue;
@$res = ($smsg->{num}, $smsg->{mid});
0; # done
}
sub num_mid0_for_oid {
my ($self, $oid, $mid) = @_;
my $res = [];
begin_lazy($self);
each_by_mid($self, $mid, ['ddd'], \&_num_mid0_for_oid, $oid, $res);
@$res, # ($num, $mid0);
}
sub create_tables {
my ($dbh) = @_;
$dbh->do(<<'');
CREATE TABLE IF NOT EXISTS over (
num INTEGER NOT NULL,
tid INTEGER NOT NULL,
sid INTEGER,
ts INTEGER,
ds INTEGER,
ddd VARBINARY, /* doc-data-deflated */
UNIQUE (num)
)
$dbh->do('CREATE INDEX IF NOT EXISTS idx_tid ON over (tid)');
$dbh->do('CREATE INDEX IF NOT EXISTS idx_sid ON over (sid)');
$dbh->do('CREATE INDEX IF NOT EXISTS idx_ts ON over (ts)');
$dbh->do('CREATE INDEX IF NOT EXISTS idx_ds ON over (ds)');
$dbh->do(<<'');
CREATE TABLE IF NOT EXISTS counter (
key VARCHAR(8) PRIMARY KEY NOT NULL,
val INTEGER DEFAULT 0,
UNIQUE (key)
)
$dbh->do("INSERT OR IGNORE INTO counter (key) VALUES ('thread')");
$dbh->do("INSERT OR IGNORE INTO counter (key) VALUES ('ghost')");
$dbh->do(<<'');
CREATE TABLE IF NOT EXISTS subject (
sid INTEGER PRIMARY KEY AUTOINCREMENT,
path VARCHAR(40) NOT NULL,
UNIQUE (path)
)
$dbh->do(<<'');
CREATE TABLE IF NOT EXISTS id2num (
id INTEGER NOT NULL,
num INTEGER NOT NULL,
UNIQUE (id, num)
)
# performance critical:
$dbh->do('CREATE INDEX IF NOT EXISTS idx_inum ON id2num (num)');
$dbh->do('CREATE INDEX IF NOT EXISTS idx_id ON id2num (id)');
$dbh->do(<<'');
CREATE TABLE IF NOT EXISTS msgid (
id INTEGER PRIMARY KEY AUTOINCREMENT,
mid VARCHAR(244) NOT NULL,
UNIQUE (mid)
)
}
sub commit_lazy {
my ($self) = @_;
delete $self->{txn} or return;
$self->{dbh}->commit;
}
sub begin_lazy {
my ($self) = @_;
return if $self->{txn};
my $dbh = $self->dbh or return;
$dbh->begin_work;
# $dbh->{Profile} = 2;
$self->{txn} = 1;
}
sub rollback_lazy {
my ($self) = @_;
delete $self->{txn} or return;
$self->{dbh}->rollback;
}
sub dbh_close {
my ($self) = @_;
die "in transaction" if $self->{txn};
$self->SUPER::dbh_close;
}
sub create {
my ($self) = @_;
unless (-r $self->{filename}) {
require File::Path;
require File::Basename;
File::Path::mkpath(File::Basename::dirname($self->{filename}));
}
# create the DB:
PublicInbox::Over::dbh($self);
$self->dbh_close;
}
sub rethread_prepare {
my ($self, $opt) = @_;
return unless $opt->{rethread};
begin_lazy($self);
my $min = $self->{min_tid} = get_counter($self->{dbh}, 'thread') // 0;
my $pr = $opt->{-progress};
$pr->("rethread min THREADID ".($min + 1)."\n") if $pr && $min;
}
sub rethread_done {
my ($self, $opt) = @_;
return unless $opt->{rethread} && $self->{txn};
defined(my $min = $self->{min_tid}) or croak('BUG: no min_tid');
my $dbh = $self->{dbh} or croak('BUG: no dbh');
my $rows = $dbh->selectall_arrayref(<<'', { Slice => {} }, $min);
SELECT num,tid FROM over WHERE num < 0 AND tid < ?
my $show_id = $dbh->prepare('SELECT id FROM id2num WHERE num = ?');
my $show_mid = $dbh->prepare('SELECT mid FROM msgid WHERE id = ?');
my $pr = $opt->{-progress};
my $total = 0;
for my $r (@$rows) {
my $exp = 0;
$show_id->execute($r->{num});
while (defined(my $id = $show_id->fetchrow_array)) {
++$exp;
$show_mid->execute($id);
my $mid = $show_mid->fetchrow_array;
if (!defined($mid)) {
warn <{num} ID=$id THREADID=$r->{tid} has no Message-ID
EOF
next;
}
$pr->(<{num} <$mid> THREADID=$r->{tid} culled
EOM
}
delete_by_num($self, $r->{num});
}
$pr->("I: rethread culled $total ghosts\n") if $pr && $total;
}
1;