1 # Copyright (C) 2015-2021 all contributors <meta@public-inbox.org>
2 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
3 # based on notmuch, but with no concept of folders, files or flags
5 # Read-only search interface for use by the web and NNTP interfaces
6 package PublicInbox::Search;
8 use parent qw(Exporter);
9 our @EXPORT_OK = qw(retry_reopen int_val get_pct xap_terms);
10 use List::Util qw(max);
11 use POSIX qw(strftime);
14 # values for searching, changing the numeric value breaks
15 # compatibility with old indices (so don't change them it)
17 TS => 0, # Received: in Unix time (IMAP INTERNALDATE, JMAP receivedAt)
18 YYYYMMDD => 1, # Date: header for searching in the WWW UI
19 DT => 2, # Date: YYYYMMDDHHMMSS (IMAP SENT*, JMAP sentAt)
21 # added for public-inbox 1.6.0+
22 BYTES => 3, # IMAP RFC822.SIZE
23 UID => 4, # IMAP UID == NNTP article number == Xapian docid
24 THREADID => 5, # RFC 8474, RFC 8621
27 # REPLYCNT => ?, # IMAP ANSWERED
29 # SCHEMA_VERSION history
31 # 1 - subject_path is lower-cased
32 # 2 - subject_path is id_compress in the index, only
33 # 3 - message-ID is compressed if it includes '%' (hack!)
34 # 4 - change "Re: " normalization, avoid circular Reference ghosts
35 # 5 - subject_path drops trailing '.'
36 # 6 - preserve References: order in document data
37 # 7 - remove references and inreplyto terms
38 # 8 - remove redundant/unneeded document data
39 # 9 - disable Message-ID compression (SHA-1)
40 # 10 - optimize doc for NNTP overviews
41 # 11 - merge threads when vivifying ghosts
42 # 12 - change YYYYMMDD value column to numeric
43 # 13 - fix threading for empty References/In-Reply-To
44 # (commit 83425ef12e4b65cdcecd11ddcb38175d4a91d5a0)
45 # 14 - fix ghost root vivification
46 # 15 - see public-inbox-v2-format(5)
47 # further bumps likely unnecessary, we'll suggest in-place
48 # "--reindex" use for further fixes and tweaks:
50 # public-inbox v1.5.0 adds (still SCHEMA_VERSION=15):
51 # * "lid:" and "l:" for List-Id searches
53 # v1.6.0 adds BYTES, UID and THREADID values
57 use PublicInbox::Smsg;
58 use PublicInbox::Over;
60 our %X = map { $_ => 0 } qw(BoolWeight Database Enquire QueryParser Stem Query);
61 our $Xap; # 'Search::Xapian' or 'Xapian'
62 our $NVRP; # '$Xap::'.('NumberValueRangeProcessor' or 'NumberRangeProcessor')
64 # ENQ_DESCENDING and ENQ_ASCENDING weren't in SWIG Xapian.pm prior to 1.4.16,
65 # let's hope the ABI is stable
66 our $ENQ_DESCENDING = 0;
67 our $ENQ_ASCENDING = 1;
70 return 1 if defined $Xap;
71 # n.b. PI_XAPIAN is intended for development use only. We still
72 # favor Search::Xapian since that's what's available in current
73 # Debian stable (10.x) and derived distros.
74 for my $x (($ENV{PI_XAPIAN} // 'Search::Xapian'), 'Xapian') {
78 $x->import(qw(:standard));
81 # `version_string' was added in Xapian 1.1
82 my $xver = eval('v'.eval($x.'::version_string()')) //
83 eval('v'.eval($x.'::xapian_version_string()'));
85 # NumberRangeProcessor was added in Xapian 1.3.6,
86 # NumberValueRangeProcessor was removed for 1.5.0+,
87 # favor the older /Value/ variant since that's what our
88 # (currently) preferred Search::Xapian supports
89 $NVRP = $x.'::'.($x eq 'Xapian' && $xver ge v1.5 ?
90 'NumberRangeProcessor' : 'NumberValueRangeProcessor');
91 $X{$_} = $Xap.'::'.$_ for (keys %X);
93 *sortable_serialise = $x.'::sortable_serialise';
94 *sortable_unserialise = $x.'::sortable_unserialise';
95 # n.b. FLAG_PURE_NOT is expensive not suitable for a public
96 # website as it could become a denial-of-service vector
97 # FLAG_PHRASE also seems to cause performance problems chert
98 # (and probably earlier Xapian DBs). glass seems fine...
99 # TODO: make this an option, maybe?
100 # or make indexlevel=medium as default
101 $QP_FLAGS = FLAG_PHRASE() | FLAG_BOOLEAN() | FLAG_LOVEHATE() |
108 # This is English-only, everything else is non-standard and may be confused as
109 # a prefix common in patch emails
110 our $LANG = 'english';
112 # note: the non-X term prefix allocations are shared with
113 # Xapian omega, see xapian-applications/omega/docs/termprefixes.rst
114 my %bool_pfx_external = (
115 mid => 'Q', # Message-ID (full/exact), this is mostly uniQue
116 lid => 'G', # newsGroup (or similar entity), just inside <>
119 dfblob => 'XDFPRE XDFPOST',
122 my $non_quoted_body = 'XNQ XDFN XDFA XDFB XDFHH XDFCTX XDFPRE XDFPOST';
124 # for mairix compatibility
126 m => 'XM', # 'mid:' (bool) is exact, 'm:' (prob) can do partial
127 l => 'XL', # 'lid:' (bool) is exact, 'l:' (prob) can do partial
134 b => $non_quoted_body . ' XQUOT',
135 bs => $non_quoted_body . ' XQUOT S',
139 nq => $non_quoted_body,
147 '' => 'XM S A XQUOT XFN ' . $non_quoted_body,
150 # not documenting m: and mid: for now, the using the URLs works w/o Xapian
151 # not documenting lid: for now, either, it is probably redundant with l:,
152 # especially since we don't offer boolean searches for To/Cc/From
155 's:' => 'match within Subject e.g. s:"a quick brown fox"',
157 date range as YYYYMMDD e.g. d:19931002..20101002
158 Open-ended ranges such as d:19931002.. and d:..20101002
162 date-time range as YYYYMMDDhhmmss (e.g. dt:19931002011000..19931002011200)
164 'b:' => 'match within message body, including text attachments',
165 'nq:' => 'match non-quoted text within message body',
166 'q:' => 'match quoted text within message body',
167 'n:' => 'match filename of attachment(s)',
168 't:' => 'match within the To header',
169 'c:' => 'match within the Cc header',
170 'f:' => 'match within the From header',
171 'a:' => 'match within the To, Cc, and From headers',
172 'tc:' => 'match within the To and Cc headers',
173 'l:' => 'match contents of the List-Id header',
174 'bs:' => 'match within the Subject and body',
175 'dfn:' => 'match filename from diff',
176 'dfa:' => 'match diff removed (-) lines',
177 'dfb:' => 'match diff added (+) lines',
178 'dfhh:' => 'match diff hunk header context (usually a function name)',
179 'dfctx:' => 'match diff context lines',
180 'dfpre:' => 'match pre-image git blob ID',
181 'dfpost:' => 'match post-image git blob ID',
182 'dfblob:' => 'match either pre or post-image git blob ID',
187 my ($self, $rdonly) = @_;
188 if ($rdonly || !defined($self->{shard})) {
190 } else { # v2 + extindex only:
191 "$self->{xpfx}/$self->{shard}";
195 # returns all shards as separate Xapian::Database objects w/o combining
196 sub xdb_shards_flat ($) {
198 my $xpfx = $self->{xpfx};
199 my (@xdb, $slow_phrase);
201 $self->{qp_flags} //= $QP_FLAGS;
202 if ($xpfx =~ m!/xapian[0-9]+\z!) {
203 @xdb = ($X{Database}->new($xpfx));
204 $self->{qp_flags} |= FLAG_PHRASE() if !-f "$xpfx/iamchert";
206 opendir(my $dh, $xpfx) or return (); # not initialized yet
207 # We need numeric sorting so shard[0] is first for reading
208 # Xapian metadata, if needed
209 my $last = max(grep(/\A[0-9]+\z/, readdir($dh))) // return ();
211 my $shard_dir = "$self->{xpfx}/$_";
212 push @xdb, $X{Database}->new($shard_dir);
213 $slow_phrase ||= -f "$shard_dir/iamchert";
215 $self->{qp_flags} |= FLAG_PHRASE() if !$slow_phrase;
220 # v2 Xapian docids don't conflict, so they're identical to
221 # NNTP article numbers and IMAP UIDs.
222 # https://trac.xapian.org/wiki/FAQ/MultiDatabaseDocumentID
224 my ($nshard, $mitem) = @_;
225 my $docid = $mitem->get_docid;
226 int(($docid - 1) / $nshard) + 1;
229 sub mset_to_artnums {
230 my ($self, $mset) = @_;
231 my $nshard = $self->{nshard};
232 [ map { mdocid($nshard, $_) } $mset->items ];
238 my @xdb = $self->xdb_shards_flat or return;
239 $self->{nshard} = scalar(@xdb);
240 my $xdb = shift @xdb;
241 $xdb->add_database($_) for @xdb;
246 # returns true if a future rescan is desired
249 return unless exists($self->{xdb});
250 my $xpfx = $self->{xpfx};
251 return reopen($self) if $xpfx =~ m!/xapian[0-9]+\z!; # true
252 opendir(my $dh, $xpfx) or return warn("$xpfx gone: $!\n"); # true
253 my $nr = grep(/\A[0-9]+\z/, readdir($dh)) or
254 return warn("$xpfx has no shards\n"); # true
255 return reopen($self) if $nr == ($self->{nshard} // -1);
256 delete($self->{xdb});
261 my ($class, $ibx) = @_;
262 ref $ibx or die "BUG: expected PublicInbox::Inbox object: $ibx";
263 my $xap = $ibx->version > 1 ? 'xap' : 'public-inbox/xapian';
264 my $xpfx = "$ibx->{inboxdir}/$xap".SCHEMA_VERSION;
265 my $self = bless { xpfx => $xpfx }, $class;
266 $self->{altid} = $ibx->{altid} if defined($ibx->{altid});
272 if (my $xdb = $self->{xdb}) {
275 $self; # make chaining easier
278 # Convert git "approxidate" ranges to something usable with our
279 # Xapian indices. At the moment, Xapian only offers a C++-only API
280 # and neither the SWIG nor XS bindings allow us to use custom code
281 # to parse dates (and libgit2 doesn't expose git__date_parse, either,
282 # so we're running git-rev-parse(1)).
283 # This replaces things we need to send to $git->date_parse with
284 # "\0".$strftime_format.['+'|$idx]."\0" placeholders
285 sub date_parse_prepare {
286 my ($to_parse, $pfx, $range) = @_;
287 # are we inside a parenthesized statement?
288 my $end = $range =~ s/([\)\s]*)\z// ? $1 : '';
289 my @r = split(/\.\./, $range, 2);
291 # expand "d:20101002" => "d:20101002..20101003" and like
292 # n.b. git doesn't do YYYYMMDD w/o '-', it needs YYYY-MM-DD
293 # We upgrade "d:" to "dt:" to iff using approxidate
295 my $fmt = "\0%Y%m%d";
296 if (!defined($r[1])) {
297 if ($r[0] =~ /\A([0-9]{4})([0-9]{2})([0-9]{2})\z/) {
298 push @$to_parse, "$1-$2-$3";
299 # we could've handled as-is, but we need
300 # to parse anyways for "d+" below
302 push @$to_parse, $r[0];
303 if ($r[0] !~ /\A[0-9]{4}-[0-9]{2}-[0-9]{2}\z/) {
305 $fmt = "\0%Y%m%d%H%M%S";
308 $r[0] = "$fmt+$#$to_parse\0";
312 next if $x eq '' || $x =~ /\A[0-9]{8}\z/;
314 if ($x !~ /\A[0-9]{4}-[0-9]{2}-[0-9]{2}\z/) {
317 $x = "$fmt$#$to_parse\0";
321 s/\0%Y%m%d/\0%Y%m%d%H%M%S/;
322 s/\A([0-9]{8})\z/${1}000000/;
326 } elsif ($pfx eq 'dt') {
327 if (!defined($r[1])) { # git needs gaps and not /\d{14}/
328 if ($r[0] =~ /\A([0-9]{4})([0-9]{2})([0-9]{2})
329 ([0-9]{2})([0-9]{2})([0-9]{2})\z/x) {
330 push @$to_parse, "$1-$2-$3 $4:$5:$6";
332 push @$to_parse, $r[0];
334 $r[0] = "\0%Y%m%d%H%M%S$#$to_parse\0";
335 $r[1] = "\0%Y%m%d%H%M%S+\0";
338 next if $x eq '' || $x =~ /\A[0-9]{14}\z/;
340 $x = "\0%Y%m%d%H%M%S$#$to_parse\0";
343 } else { # "rt", let git interpret "YYYY", deal with Y10K later :P
345 next if $x eq '' || $x =~ /\A[0-9]{5,}\z/;
347 $x = "\0%s$#$to_parse\0";
349 $r[1] //= "\0%s+\0"; # add 1 day
351 "$pfx:".join('..', @r).$end;
354 sub date_parse_finalize {
355 my ($git, $to_parse) = @_;
356 # git-rev-parse can handle any number of args up to system
357 # limits (around (4096*32) bytes on Linux).
358 my @r = $git->date_parse(@$to_parse);
359 # n.b. git respects TZ, times stored in SQLite/Xapian are always UTC,
360 # and gmtime doesn't seem to do the right thing when TZ!=UTC
362 $_[2] =~ s/\0(%[%YmdHMSs]+)([0-9\+]+)\0/
363 $t = $2 eq '+' ? ($r[$i]+86400) : $r[$i=$2+0];
364 $1 eq '%s' ? $t : strftime($1, gmtime($t))/sge;
367 # n.b. argv never has NUL, though we'll need to filter it out
368 # if this $argv isn't from a command execution
369 sub query_argv_to_string {
370 my (undef, $git, $argv) = @_;
372 my $tmp = join(' ', map {;
373 if (s!\b(d|rt|dt):(\S+)\z!date_parse_prepare(
374 $to_parse //= [], $1, $2)!sge) {
377 s/(.*?)\b(\w+:)// ? qq{$1$2"$_"} : qq{"$_"};
382 date_parse_finalize($git, $to_parse, $tmp) if $to_parse;
386 # this is for the WWW "q=" query parameter and "lei q --stdin"
387 # it can't do d:"5 days ago", but it will do d:5.days.ago
388 sub query_approxidate {
389 my (undef, $git) = @_; # $_[2] = $query_string (modified in-place)
390 my $DQ = qq<"\x{201c}\x{201d}>; # Xapian can use curly quotes
391 $_[2] =~ tr/\x00/ /; # Xapian doesn't do NUL, we use it as a placeholder
392 my ($terms, $phrase, $to_parse);
393 $_[2] =~ s{([^$DQ]*)([$DQ][^$DQ]*[$DQ])?}{
394 ($terms, $phrase) = ($1, $2);
395 $terms =~ s!\b(d|rt|dt):(\S+)!
396 date_parse_prepare($to_parse //= [], $1, $2)!sge;
397 $terms.($phrase // '');
399 date_parse_finalize($git, $to_parse, $_[2]) if $to_parse;
404 my ($self, $query_string, $opts) = @_;
406 my $qp = $self->{qp} //= $self->qparse_new;
407 my $query = $qp->parse_query($query_string, $self->{qp_flags});
408 _do_enquire($self, $query, $opts);
412 my ($self, $cb, @arg) = @_;
416 eval { @ret = $cb->($self, @arg) };
417 return @ret unless $@;
420 eval { $ret = $cb->($self, @arg) };
421 return $ret unless $@;
423 # Exception: The revision being read has been discarded -
424 # you should call Xapian::Database::reopen()
425 if (ref($@) =~ /\bDatabaseModifiedError\b/) {
428 # let caller decide how to spew, because ExtMsg queries
429 # get wonky and trigger:
430 # "something terrible happened at .../Xapian/Enquire.pm"
434 Carp::croak("Too many Xapian database modifications in progress\n");
438 my ($self, $query, $opts) = @_;
439 retry_reopen($self, \&_enquire_once, $query, $opts);
442 # returns true if all docs have the THREADID value
443 sub has_threadid ($) {
445 (xdb($self)->get_metadata('has_threadid') // '') eq '1';
448 sub _enquire_once { # retry_reopen callback
449 my ($self, $query, $opts) = @_;
450 my $xdb = xdb($self);
451 if (defined(my $eidx_key = $opts->{eidx_key})) {
452 $query = $X{Query}->new(OP_FILTER(), $query, 'O'.$eidx_key);
454 if (defined(my $uid_range = $opts->{uid_range})) {
455 my $range = $X{Query}->new(OP_VALUE_RANGE(), UID,
456 sortable_serialise($uid_range->[0]),
457 sortable_serialise($uid_range->[1]));
458 $query = $X{Query}->new(OP_FILTER(), $query, $range);
460 my $enquire = $X{Enquire}->new($xdb);
461 $enquire->set_query($query);
463 my $rel = $opts->{relevance} // 0;
464 if ($rel == -2) { # ORDER BY docid/UID (highest first)
465 $enquire->set_weighting_scheme($X{BoolWeight}->new);
466 $enquire->set_docid_order($ENQ_DESCENDING);
467 } elsif ($rel == -1) { # ORDER BY docid/UID (lowest first)
468 $enquire->set_weighting_scheme($X{BoolWeight}->new);
469 $enquire->set_docid_order($ENQ_ASCENDING);
470 } elsif ($rel == 0) {
471 $enquire->set_sort_by_value_then_relevance(TS, !$opts->{asc});
473 $enquire->set_sort_by_relevance_then_value(TS, !$opts->{asc});
476 # `mairix -t / --threads' or JMAP collapseThreads
477 if ($opts->{threads} && has_threadid($self)) {
478 $enquire->set_collapse_key(THREADID);
480 $enquire->get_mset($opts->{offset} || 0, $opts->{limit} || 50);
484 my ($self, $ibx, $mset) = @_;
485 my $nshard = $self->{nshard};
487 my %order = map { mdocid($nshard, $_) => ++$i } $mset->items;
489 $order{$a->{num}} <=> $order{$b->{num}}
490 } @{$ibx->over->get_all(keys %order)};
491 wantarray ? ($mset->get_matches_estimated, \@msgs) : \@msgs;
495 sub stemmer { $X{Stem}->new($LANG) }
501 my $xdb = xdb($self);
502 my $qp = $X{QueryParser}->new;
503 $qp->set_default_op(OP_AND());
504 $qp->set_database($xdb);
505 $qp->set_stemmer(stemmer($self));
506 $qp->set_stemming_strategy(STEM_SOME());
507 my $cb = $qp->can('set_max_wildcard_expansion') //
508 $qp->can('set_max_expansion'); # Xapian 1.5.0+
510 $cb = $qp->can('add_valuerangeprocessor') //
511 $qp->can('add_rangeprocessor'); # Xapian 1.5.0+
512 $cb->($qp, $NVRP->new(YYYYMMDD, 'd:'));
513 $cb->($qp, $NVRP->new(DT, 'dt:'));
515 # for IMAP, undocumented for WWW and may be split off go away
516 $cb->($qp, $NVRP->new(BYTES, 'z:'));
517 $cb->($qp, $NVRP->new(TS, 'rt:'));
518 $cb->($qp, $NVRP->new(UID, 'uid:'));
520 while (my ($name, $prefix) = each %bool_pfx_external) {
521 $qp->add_boolean_prefix($name, $_) foreach split(/ /, $prefix);
524 # we do not actually create AltId objects,
525 # just parse the spec to avoid the extra DB handles for now.
526 if (my $altid = $self->{altid}) {
527 my $user_pfx = $self->{-user_pfx} = [];
529 # $_ = 'serial:gmane:/path/to/gmane.msgmap.sqlite3'
530 # note: Xapian supports multibyte UTF-8, /^[0-9]+$/,
531 # and '_' with prefixes matching \w+
532 /\Aserial:(\w+):/ or next;
534 push @$user_pfx, "$pfx:", <<EOF;
535 alternate serial number e.g. $pfx:12345 (boolean)
538 $qp->add_boolean_prefix($pfx, 'X'.uc($pfx));
543 while (my ($name, $prefix) = each %prob_prefix) {
544 $qp->add_prefix($name, $_) foreach split(/ /, $prefix);
551 $self->{qp} //= $self->qparse_new; # parse altids
553 if (my $user_pfx = $self->{-user_pfx}) {
554 push @ret, @$user_pfx;
560 my ($doc, $col) = @_;
561 my $val = $doc->get_value($col) or return; # undefined is '' in Xapian
562 sortable_unserialise($val) + 0; # PV => IV conversion
565 sub get_pct ($) { # mset item
566 # Capped at "99%" since "100%" takes an extra column in the
567 # thread skeleton view. <xapian/mset.h> says the value isn't
568 # very meaningful, anyways.
569 my $n = $_[0]->get_percent;
573 sub xap_terms ($$;@) {
574 my ($pfx, $xdb_or_doc, @docid) = @_; # @docid may be empty ()
576 my $end = $xdb_or_doc->termlist_end(@docid);
577 my $cur = $xdb_or_doc->termlist_begin(@docid);
578 for (; $cur != $end; $cur++) {
580 last if $cur == $end;
581 my $tn = $cur->get_termname;
582 $ret{substr($tn, length($pfx))} = undef if !index($tn, $pfx);
584 wantarray ? sort(keys(%ret)) : \%ret;