# Copyright (C) 2015-2018 all contributors # License: AGPL-3.0+ # bidirectional Message-ID <-> Article Number mapping for the NNTP # and web interfaces. This is required for implementing stable article # numbers for NNTP and allows prefix lookups for partial Message-IDs # in case URLs get truncated from copy-n-paste errors by users. # # This is maintained by ::SearchIdx package PublicInbox::Msgmap; use strict; use warnings; use DBI; use DBD::SQLite; use File::Temp qw(tempfile); sub new { my ($class, $git_dir, $writable) = @_; my $d = "$git_dir/public-inbox"; if ($writable && !-d $d && !mkdir $d) { my $err = $!; -d $d or die "$d not created: $err"; } new_file($class, "$d/msgmap.sqlite3", $writable); } sub dbh_new { my ($f, $writable) = @_; if ($writable && !-f $f) { # SQLite defaults mode to 0644, we want 0666 open my $fh, '+>>', $f or die "failed to open $f: $!"; } my $dbh = DBI->connect("dbi:SQLite:dbname=$f",'','', { AutoCommit => 1, RaiseError => 1, PrintError => 0, ReadOnly => !$writable, sqlite_use_immediate_transaction => 1, }); $dbh; } sub new_file { my ($class, $f, $writable) = @_; return if !$writable && !-r $f; my $dbh = dbh_new($f, $writable); my $self = bless { dbh => $dbh }, $class; if ($writable) { create_tables($dbh); $dbh->begin_work; $self->created_at(time) unless $self->created_at; my (undef, $max) = $self->minmax(); $max ||= 0; $self->num_highwater($max); $dbh->commit; } $self; } # used to keep track of used numeric mappings for v2 reindex sub tmp_clone { my ($self) = @_; my ($fh, $fn) = tempfile('msgmap-XXXXXXXX', EXLOCK => 0, TMPDIR => 1); $self->{dbh}->sqlite_backup_to_file($fn); my $tmp = ref($self)->new_file($fn, 1); $tmp->{dbh}->do('PRAGMA synchronous = OFF'); $tmp->{tmp_name} = $fn; # SQLite won't work if unlinked, apparently $tmp->{pid} = $$; close $fh or die "failed to close $fn: $!"; $tmp; } # n.b. invoked directly by scripts/xhdr-num2mid sub meta_accessor { my ($self, $key, $value) = @_; my $sql = 'SELECT val FROM meta WHERE key = ? LIMIT 1'; my $dbh = $self->{dbh}; my $prev; defined $value or return $dbh->selectrow_array($sql, undef, $key); $prev = $dbh->selectrow_array($sql, undef, $key); if (defined $prev) { $sql = 'UPDATE meta SET val = ? WHERE key = ?'; $dbh->do($sql, undef, $value, $key); } else { $sql = 'INSERT INTO meta (key,val) VALUES (?,?)'; $dbh->do($sql, undef, $key, $value); } $prev; } sub last_commit { my ($self, $commit) = @_; $self->meta_accessor('last_commit', $commit); } # v2 uses this to keep track of how up-to-date Xapian is # old versions may be automatically GC'ed away in the future, # but it's a trivial amount of storage. sub last_commit_xap { my ($self, $version, $i, $commit) = @_; $self->meta_accessor("last_xap$version-$i", $commit); } sub created_at { my ($self, $second) = @_; $self->meta_accessor('created_at', $second); } sub num_highwater { my ($self, $num) = @_; my $high = $self->{num_highwater} ||= $self->meta_accessor('num_highwater'); if (defined($num) && (!defined($high) || ($num > $high))) { $self->{num_highwater} = $num; $self->meta_accessor('num_highwater', $num); } $self->{num_highwater}; } sub mid_insert { my ($self, $mid) = @_; my $dbh = $self->{dbh}; my $sth = $dbh->prepare_cached(<<''); INSERT OR IGNORE INTO msgmap (mid) VALUES (?) return if $sth->execute($mid) == 0; my $num = $dbh->last_insert_id(undef, undef, 'msgmap', 'num'); $self->num_highwater($num) if defined($num); $num; } sub mid_for { my ($self, $num) = @_; my $dbh = $self->{dbh}; my $sth = $self->{mid_for} ||= $dbh->prepare('SELECT mid FROM msgmap WHERE num = ? LIMIT 1'); $sth->bind_param(1, $num); $sth->execute; $sth->fetchrow_array; } sub num_for { my ($self, $mid) = @_; my $dbh = $self->{dbh}; my $sth = $self->{num_for} ||= $dbh->prepare('SELECT num FROM msgmap WHERE mid = ? LIMIT 1'); $sth->bind_param(1, $mid); $sth->execute; $sth->fetchrow_array; } sub minmax { my ($self) = @_; my $dbh = $self->{dbh}; # breaking MIN and MAX into separate queries speeds up from 250ms # to around 700us with 2.7million messages. my $sth = $dbh->prepare_cached('SELECT MIN(num) FROM msgmap', undef, 1); $sth->execute; my $min = $sth->fetchrow_array; $sth = $dbh->prepare_cached('SELECT MAX(num) FROM msgmap', undef, 1); $sth->execute; ($min, $sth->fetchrow_array); } sub mid_delete { my ($self, $mid) = @_; my $dbh = $self->{dbh}; my $sth = $dbh->prepare('DELETE FROM msgmap WHERE mid = ?'); $sth->bind_param(1, $mid); $sth->execute; } sub num_delete { my ($self, $num) = @_; my $dbh = $self->{dbh}; my $sth = $dbh->prepare('DELETE FROM msgmap WHERE num = ?'); $sth->bind_param(1, $num); $sth->execute; } sub create_tables { my ($dbh) = @_; my $e; $e = eval { $dbh->selectrow_array('EXPLAIN SELECT * FROM msgmap;') }; defined $e or $dbh->do('CREATE TABLE msgmap (' . 'num INTEGER PRIMARY KEY AUTOINCREMENT, '. 'mid VARCHAR(1000) NOT NULL, ' . 'UNIQUE (mid) )'); $e = eval { $dbh->selectrow_array('EXPLAIN SELECT * FROM meta') }; defined $e or $dbh->do('CREATE TABLE meta (' . 'key VARCHAR(32) PRIMARY KEY, '. 'val VARCHAR(255) NOT NULL)'); } # used by NNTP.pm sub ids_after { my ($self, $num) = @_; my $ids = $self->{dbh}->selectcol_arrayref(<<'', undef, $$num); SELECT num FROM msgmap WHERE num > ? ORDER BY num ASC LIMIT 1000 $$num = $ids->[-1] if @$ids; $ids; } sub msg_range { my ($self, $beg, $end) = @_; my $dbh = $self->{dbh}; my $attr = { Columns => [] }; my $mids = $dbh->selectall_arrayref(<<'', $attr, $$beg, $end); SELECT num,mid FROM msgmap WHERE num >= ? AND num <= ? ORDER BY num ASC LIMIT 1000 $$beg = $mids->[-1]->[0] + 1 if @$mids; $mids } # only used for mapping external serial numbers (e.g. articles from gmane) # see scripts/xhdr-num2mid or PublicInbox::Filter::RubyLang for usage sub mid_set { my ($self, $num, $mid) = @_; my $sth = $self->{mid_set} ||= do { $self->{dbh}->prepare( 'INSERT OR IGNORE INTO msgmap (num,mid) VALUES (?,?)'); }; my $result = $sth->execute($num, $mid); $self->num_highwater($num) if (defined($result) && $result == 1); $result; } sub DESTROY { my ($self) = @_; delete $self->{dbh}; my $f = delete $self->{tmp_name}; if (defined $f && $self->{pid} == $$) { unlink $f or warn "failed to unlink $f: $!\n"; } } sub atfork_parent { my ($self) = @_; my $f = $self->{tmp_name} or die "not a temporary clone\n"; delete $self->{dbh} and die "tmp_clone dbh not prepared for parent"; my $dbh = $self->{dbh} = dbh_new($f, 1); $dbh->do('PRAGMA synchronous = OFF'); } sub atfork_prepare { my ($self) = @_; my $f = $self->{tmp_name} or die "not a temporary clone\n"; $self->{pid} == $$ or die "BUG: atfork_prepare not called from $self->{pid}\n"; $self->{dbh} or die "temporary clone not open\n"; # must clobber prepared statements %$self = (tmp_name => $f, pid => $$); } 1;