summaryrefslogtreecommitdiff
path: root/lib/TUWF/DB.pm
blob: a5836093771cf11a1cb365555c903a796e836fd2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248

package TUWF::DB;

use strict;
use warnings;
use Carp 'croak';
use Exporter 'import';
use Time::HiRes 'time';

our $VERSION = '1.4';
our @EXPORT = qw|
  dbInit dbh dbCheck dbDisconnect dbCommit dbRollBack
  dbExec dbVal dbRow dbAll dbPage
|;
our @EXPORT_OK = ('sqlprint');


sub dbInit {
  my $self = shift;
  require DBI;
  my $login = $self->{_TUWF}{db_login};
  my $sql;
  if(ref($login) eq 'CODE') {
    $sql = $login->($self);
    croak 'db_login subroutine did not return a DBI instance.' if !ref($sql) || !$sql->isa('DBI::db');
  } elsif(ref($login) eq 'ARRAY' && @$login == 3) {
    $sql = DBI->connect(@$login, {
      PrintError => 0, RaiseError => 1, AutoCommit => 0,
      mysql_enable_utf8 => 1, # DBD::mysql
      pg_enable_utf8    => 1, # DBD::Pg
      sqlite_unicode    => 1, # DBD::SQLite
    });
  } else {
    croak 'Invalid value for the db_login setting.';
  }
  $sql->{private_tuwf} = 1;
  inject_logging();

  $self->{_TUWF}{DB} = {
    sql => $sql,
    queries => [],
  };
}


sub dbh {
  return shift->{_TUWF}{DB}{sql};
}


sub dbCheck {
  my $self = shift;
  my $info = $self->{_TUWF}{DB};

  my $start = time;
  $info->{queries} = [];

  if(!$info->{sql}->ping) {
    warn "Ping failed, reconnecting";
    $self->dbInit;
  }
  $self->dbRollBack;
  push(@{$info->{queries}}, [ 'ping/rollback', {}, time-$start ]);
}


sub dbDisconnect {
  shift->{_TUWF}{DB}{sql}->disconnect();
}


sub dbCommit {
  my $self = shift;
  my $start = [Time::HiRes::gettimeofday()] if $self->debug || $self->{_TUWF}{log_slow_pages};
  $self->{_TUWF}{DB}{sql}->commit();
  push(@{$self->{_TUWF}{DB}{queries}}, [ 'commit', {}, Time::HiRes::tv_interval($start) ])
    if $self->debug || $self->{_TUWF}{log_slow_pages};
}


sub dbRollBack {
  shift->{_TUWF}{DB}{sql}->rollback();
}


# execute a query and return the number of rows affected
sub dbExec {
  return sqlhelper(shift, 0, @_);
}


# ..return the first column of the first row
sub dbVal {
  return sqlhelper(shift, 1, @_);
}


# ..return the first row as an hashref
sub dbRow {
  return sqlhelper(shift, 2, @_);
}


# ..return all rows as an arrayref of hashrefs
sub dbAll {
  return sqlhelper(shift, 3, @_);
}


# same as dbAll, but paginates results by adding
# an OFFSET and LIMIT to the query, the first argument
# should be a hashref with the keys page and results.
# Returns the usual value from dbAll and a value
# indicating whether there is a next page
sub dbPage {
  my($s, $o, $q, @a) = @_;
  my $r = $s->dbAll($q.' LIMIT ? OFFSET ?', @a, $o->{results}+(wantarray?1:0), $o->{results}*($o->{page}-1));
  return $r if !wantarray;
  return ($r, 0) if $#$r != $o->{results};
  pop @$r;
  return ($r, 1);
}


sub sqlhelper { # type, query, @list
  my $self = shift;
  my $type = shift;
  my $sqlq = shift;

  $sqlq =~ s/\r?\n/ /g;
  $sqlq =~ s/  +/ /g;
  my(@q) = @_ ? sqlprint($sqlq, @_) : ($sqlq);

  my($q, $r);
  my $ret = eval {
    $q = $self->dbh->prepare($q[0]);
    $q->execute($#q ? @q[1..$#q] : ());
    $r = $type == 1 ? ($q->fetchrow_array)[0] :
         $type == 2 ? $q->fetchrow_hashref :
         $type == 3 ? $q->fetchall_arrayref({}) :
                      $q->rows;
    1;
  };

  # re-throw the error in the context of the calling code
  croak($self->dbh->errstr || $@) if !$ret;

  $r = 0  if $type == 0 && (!$r || $r == 0);
  $r = {} if $type == 2 && (!$r || ref($r) ne 'HASH');
  $r = [] if $type == 3 && (!$r || ref($r) ne 'ARRAY');

  return $r;
}


# sqlprint:
#   ?    normal placeholder
#   !l   list of placeholders, expects arrayref
#   !H   list of SET-items, expects hashref or arrayref: format => (bind_value || \@bind_values)
#   !W   same as !H, but for WHERE clauses (AND'ed together)
#   !s   the classic sprintf %s, use with care
# This isn't sprintf, so all other things won't work,
# Only the ? placeholder is supported, so no dollar sign numbers or named placeholders

sub sqlprint { # query, bind values. Returns new query + bind values
  my @a;
  my $q='';
  for my $p (split /(\?|![lHWs])/, shift) {
    next if !defined $p;
    if($p eq '?') {
      push @a, shift;
      $q .= $p;
    } elsif($p eq '!s') {
      $q .= shift;
    } elsif($p eq '!l') {
      my $l = shift;
      $q .= join ', ', map '?', 0..$#$l;
      push @a, @$l;
    } elsif($p eq '!H' || $p eq '!W') {
      my $h=shift;
      my @h=ref $h eq 'HASH' ? %$h : @$h;
      my @r;
      while(my($k,$v) = (shift(@h), shift(@h))) {
        last if !defined $k;
        my($n,@l) = sqlprint($k, ref $v eq 'ARRAY' ? @$v : $v);
        push @r, $n;
        push @a, @l;
      }
      $q .= ($p eq '!W' ? 'WHERE ' : 'SET ').join $p eq '!W' ? ' AND ' : ', ', @r
        if @r;
    } else {
      $q .= $p;
    }
  }
  return($q, @a);
}


# There are generally two approaches to adding logging to DBI: The common and
# clean approach is to subclass DBD::st and DBD::db (e.g. DBIx::LogAny). But
# subclassing doesn't stack nicely, and you may need to implement more methods
# because methods calling each other internally won't be caught.
#
# The other approach is to replace the methods of DBD::st and DBD::db directly,
# as done in DBI::Log. The downside is that it's hacky, unreliable when DBD::*
# modules come with their own implementation of something, and this approach
# affects *all* DBI interation and not just those of selected handlers. The
# latter issue is easily solved by setting a private flag in the DBI object
# ('private_tuwf' in this case).
sub inject_logging {
  require DBI;
  no warnings 'redefine';

  # The measured SQL timing only includes that of the execute() call, but it's
  # likely that some query processing also happens during fetching.
  # Unfortunately, I haven't found a reliable way to trigger on "Okay, I'm done
  # with executing and fetching this statement". The final() method is not
  # implicitely called, and adding an object destructor wouldn't work with
  # cached prepared statements.
  my $orig_execute = \&DBI::st::execute;
  *DBI::st::execute = sub {
    my($self) = @_;
    my $start = time;
    my $ret = $orig_execute->(@_);

    if($self->{Database}{private_tuwf}) {
      my $time = time - $start;
      my %params = %{$self->{ParamValues} || {}};

      $TUWF::OBJ->log(sprintf
        '[%7.2fms] %s | %s',
        $time*1000,
        $self->{Statement},
        join ', ',
          map "$_:".DBI::neat($params{$_}),
          sort { $a =~ /^[0-9]+$/ && $b =~ /^[0-9]+$/ ? $a <=> $b : $a cmp $b }
          keys %params
      ) if $TUWF::OBJ->{_TUWF}{log_queries};

      push @{$TUWF::OBJ->{_TUWF}{DB}{queries}}, [ $self->{Statement}, \%params , $time ];
    }

    return $ret;
  };
}


1;