From 961e6ff825027765ee22d7cbec0edc9d122ad28f Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Sat, 1 Nov 2014 00:18:57 +0300
Subject: [PATCH] Support logging DB queries

---
 Bugzilla.pm                                   |   3 +-
 Bugzilla/Config/General.pm                    |   6 +
 Bugzilla/DB.pm                                | 129 ++++++++++++++++++
 Bugzilla/DB/Oracle.pm                         |   3 +-
 .../en/default/admin/params/general.html.tmpl |   3 +
 5 files changed, 141 insertions(+), 3 deletions(-)

diff --git a/Bugzilla.pm b/Bugzilla.pm
index 34e08cdd0..6bb0d5f00 100644
--- a/Bugzilla.pm
+++ b/Bugzilla.pm
@@ -200,8 +200,6 @@ sub _tt_provider_load_compiled
 # Global Code
 #####################################################################
 
-# $::SIG{__DIE__} = i_am_cgi() ? \&CGI::Carp::confess : \&Carp::confess;
-
 # Note that this is a raw subroutine, not a method, so $class isn't available.
 sub init_page
 {
@@ -1083,6 +1081,7 @@ sub _cleanup
     {
         next if !$dbh;
         $dbh->bz_rollback_transaction() if $dbh->bz_in_transaction;
+        $dbh->write_query_log;
         $dbh->disconnect;
     }
     undef $_request_cache;
diff --git a/Bugzilla/Config/General.pm b/Bugzilla/Config/General.pm
index a2c39709f..6d2b72695 100644
--- a/Bugzilla/Config/General.pm
+++ b/Bugzilla/Config/General.pm
@@ -95,6 +95,12 @@ use constant get_param_list => (
         default => 0,
     },
 
+    {
+        name => 'query_log',
+        type => 't',
+        default => '',
+    },
+
     {
         name => 'docs_urlbase',
         type => 't',
diff --git a/Bugzilla/DB.pm b/Bugzilla/DB.pm
index 7ba9725b4..f4327287c 100644
--- a/Bugzilla/DB.pm
+++ b/Bugzilla/DB.pm
@@ -44,6 +44,7 @@ use Bugzilla::Error;
 use Bugzilla::DB::Schema;
 
 use List::Util qw(max);
+use POSIX qw(strftime);
 use Storable qw(dclone);
 
 #####################################################################
@@ -1474,6 +1475,134 @@ sub _check_references {
     }
 }
 
+sub interpolate_params
+{
+    my $self = shift;
+    my ($sql, $bind) = @_;
+    my $r = '';
+    # match unquoted part + any number of quoted strings/identifiers
+    while ($sql =~ s!^([^"`']*)((?:`(?:[^`]+|``)*`|"(?:[^"\\]+|\\.|"")*"|'(?:[^'\\]+|\\.|'')*)*)!!so)
+    {
+        my ($c, $q) = ($1, $2);
+        last if $c eq '' && $q eq '';
+        $c =~ s/\?/$self->quote(shift @$bind)/geso;
+        $r .= $c.$q;
+    }
+    return $r;
+}
+
+sub write_query_log
+{
+    my $self = shift;
+    if (my $logfile = Bugzilla->params->{query_log})
+    {
+        # Log queries
+        $logfile = bz_locations()->{datadir} . '/' . $logfile if substr($logfile, 0, 1) ne '/';
+        trick_taint($logfile);
+        my $fd;
+        my @q = @{ tied(%$self)->{_logged_queries} || [] };
+        if (@q && open $fd, ">>", $logfile)
+        {
+            print $fd strftime("[%Y-%m-%d %H:%M:%S] ", localtime) .
+                "[pid=$$] $ENV{REQUEST_URI} DB queries:\n" . join("\n", map { $self->interpolate_params(@$_).';' } @q) . "\n\n";
+            close $fd;
+        }
+        tied(%$self)->{_logged_queries} = [];
+    }
+}
+
+sub log_query
+{
+    my $self = shift;
+    push @{tied(%$self)->{_logged_queries}}, [ @_ ] if Bugzilla->params->{query_log};
+}
+
+sub get_logged_queries
+{
+    my $self = shift;
+    return tied(%$self)->{_logged_queries} || [];
+}
+
+sub do
+{
+    my $self = shift;
+    my ($sql, undef, @bind) = @_;
+    $self->log_query($sql, \@bind);
+    $self->SUPER::do(@_);
+}
+
+sub selectrow_array
+{
+    my $self = shift;
+    my ($sql, undef, @bind) = @_;
+    $self->log_query($sql, \@bind);
+    return $self->SUPER::selectrow_array(@_);
+}
+
+sub selectrow_arrayref
+{
+    my $self = shift;
+    my ($sql, undef, @bind) = @_;
+    $self->log_query($sql, \@bind);
+    return $self->SUPER::selectrow_array(@_);
+}
+
+sub selectrow_hashref
+{
+    my $self = shift;
+    my ($sql, undef, @bind) = @_;
+    $self->log_query($sql, \@bind);
+    return $self->SUPER::selectrow_hashref(@_);
+}
+
+sub selectall_hashref
+{
+    my $self = shift;
+    my ($sql, undef, @bind) = @_;
+    $self->log_query($sql, \@bind);
+    return $self->SUPER::selectall_hashref(@_);
+}
+
+sub selectall_arrayref
+{
+    my $self = shift;
+    my ($sql, undef, @bind) = @_;
+    $self->log_query($sql, \@bind);
+    return $self->SUPER::selectall_arrayref(@_);
+}
+
+sub selectcol_arrayref
+{
+    my $self = shift;
+    my ($sql, undef, @bind) = @_;
+    $self->log_query($sql, \@bind);
+    return $self->SUPER::selectcol_arrayref(@_);
+}
+
+sub prepare
+{
+    my $self = shift;
+    return bless $self->SUPER::prepare(@_), 'Bugzilla::DB::st';
+}
+
+sub prepare_cached
+{
+    my $self = shift;
+    return bless $self->SUPER::prepare_cached(@_), 'Bugzilla::DB::st';
+}
+
+package Bugzilla::DB::st;
+
+use base qw(DBI::st);
+
+sub execute
+{
+    my $self = shift;
+    my $dbh = tied(%$self)->{Database}->{Driver}->{ChildHandles};
+    $dbh->[$#$dbh]->log_query(tied(%$self)->{Statement}, [ @_ ]);
+    return $self->SUPER::execute(@_);
+}
+
 1;
 
 __END__
diff --git a/Bugzilla/DB/Oracle.pm b/Bugzilla/DB/Oracle.pm
index f60bef232..ac255da10 100644
--- a/Bugzilla/DB/Oracle.pm
+++ b/Bugzilla/DB/Oracle.pm
@@ -778,7 +778,8 @@ sub bz_setup_database {
 }
 
 package Bugzilla::DB::Oracle::st;
-use base qw(DBI::st);
+
+use base qw(Bugzilla::DB::st);
 
 sub fetchrow_arrayref
 {
diff --git a/template/en/default/admin/params/general.html.tmpl b/template/en/default/admin/params/general.html.tmpl
index 7de7229c1..cafe70e4c 100644
--- a/template/en/default/admin/params/general.html.tmpl
+++ b/template/en/default/admin/params/general.html.tmpl
@@ -40,6 +40,9 @@
   report_user_errors_to_maintainer =>
     "Whether to send e-mail messages about each 'user' (invalid input, non-fatal) error to Bugzilla maintainer (not recommended).",
 
+  query_log =>
+    "<b>Use only for debug purposes!</b> Path to the file to which Bugzilla should log all database queries with all parameters.",
+
   docs_urlbase =>
     "The URL that is the common initial leading part of all"
     _ " $terms.Bugzilla documentation URLs. It may be an absolute URL,"