msgmap: mid_insert ignores duplicates instead of die-ing

[public-inbox.git] / lib / PublicInbox / Msgmap.pm

diff --git a/lib/PublicInbox/Msgmap.pm b/lib/PublicInbox/Msgmap.pm
index 8a34e7e0c713a4036cd156de22795a525320e5d7..a49b61e8b7f3636eb28cba61ca052c5000b5720c 100644 (file)
--- a/lib/PublicInbox/Msgmap.pm
+++ b/lib/PublicInbox/Msgmap.pm
@@ -1,6 +1,12 @@
 # Copyright (C) 2015 all contributors <meta@public-inbox.org>
 # License: AGPLv3 or later (https://www.gnu.org/licenses/agpl-3.0.txt)
-# bidirectional Message-ID <-> Article Number mapping
+
+# 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;
@@ -14,11 +20,17 @@ sub new {
                my $err = $!;
                -d $d or die "$d not created: $err";
        }
-       my $f = "$d/msgmap.sqlite3";
+       new_file($class, "$d/msgmap.sqlite3", $writable);
+}
+
+sub new_file {
+       my ($class, $f, $writable) = @_;
+
        my $dbh = DBI->connect("dbi:SQLite:dbname=$f",'','', {
                AutoCommit => 1,
                RaiseError => 1,
                PrintError => 0,
+               ReadOnly => !$writable,
                sqlite_use_immediate_transaction => 1,
        });
        $dbh->do('PRAGMA case_sensitive_like = ON');
@@ -26,11 +38,14 @@ sub new {
 
        if ($writable) {
                create_tables($dbh);
+               $dbh->begin_work;
                $self->created_at(time) unless $self->created_at;
+               $dbh->commit;
        }
        $self;
 }
 
+# n.b. invoked directly by scripts/xhdr-num2mid
 sub meta_accessor {
        my ($self, $key, $value) = @_;
        use constant {
@@ -44,22 +59,14 @@ sub meta_accessor {
        defined $value or
                return $dbh->selectrow_array(meta_select, undef, $key);
 
-       $dbh->begin_work;
-       eval {
-               $prev = $dbh->selectrow_array(meta_select, undef, $key);
+       $prev = $dbh->selectrow_array(meta_select, undef, $key);
 
-               if (defined $prev) {
-                       $dbh->do(meta_update, undef, $value, $key);
-               } else {
-                       $dbh->do(meta_insert, undef, $key, $value);
-               }
-               $dbh->commit;
-       };
-       my $err = $@;
-       return $prev unless $err;
-
-       $dbh->rollback;
-       die $err;
+       if (defined $prev) {
+               $dbh->do(meta_update, undef, $value, $key);
+       } else {
+               $dbh->do(meta_insert, undef, $key, $value);
+       }
+       $prev;
 }
 
 sub last_commit {
@@ -75,10 +82,10 @@ sub created_at {
 sub mid_insert {
        my ($self, $mid) = @_;
        my $dbh = $self->{dbh};
-       use constant MID_INSERT => 'INSERT INTO msgmap (mid) VALUES (?)';
-       my $sth = $self->{mid_insert} ||= $dbh->prepare(MID_INSERT);
+       my $sql = 'INSERT OR IGNORE INTO msgmap (mid) VALUES (?)';
+       my $sth = $self->{mid_insert} ||= $dbh->prepare($sql);
        $sth->bind_param(1, $mid);
-       $sth->execute;
+       return if $sth->execute == 0;
        $dbh->last_insert_id(undef, undef, 'msgmap', 'num');
 }
 
@@ -153,6 +160,7 @@ sub create_tables {
                        'val VARCHAR(255) NOT NULL)');
 }
 
+# used by NNTP.pm
 sub id_batch {
        my ($self, $num, $cb) = @_;
        my $dbh = $self->{dbh};
@@ -166,4 +174,15 @@ sub id_batch {
        $nr;
 }
 
+# only used for mapping external serial numbers (e.g. articles from gmane)
+# see scripts/xhdr-num2mid for usage
+sub mid_set {
+       my ($self, $num, $mid) = @_;
+       my $sth = $self->{mid_set} ||= do {
+               my $sql = 'INSERT INTO msgmap (num, mid) VALUES (?,?)';
+               $self->{dbh}->prepare($sql);
+       };
+       $sth->execute($num, $mid);
+}
+
 1;