summaryrefslogtreecommitdiffstats
path: root/Bugzilla/DB/Schema/Sqlite.pm
blob: 6d524db593b4466d76afdcb5d63fe2d6200f80bb (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
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
# This Source Code Form is "Incompatible With Secondary Licenses", as
# defined by the Mozilla Public License, v. 2.0.

package Bugzilla::DB::Schema::Sqlite;

use 5.10.1;
use strict;
use warnings;

use base qw(Bugzilla::DB::Schema);

use Bugzilla::Error;
use Bugzilla::Util qw(generate_random_password);

use Storable qw(dclone);

use constant FK_ON_CREATE => 1;

sub _initialize {

    my $self = shift;

    $self = $self->SUPER::_initialize(@_);

    $self->{db_specific} = {
        BOOLEAN =>      'integer',
        FALSE =>        '0',
        TRUE =>         '1',

        INT1 =>         'integer',
        INT2 =>         'integer',
        INT3 =>         'integer',
        INT4 =>         'integer',

        SMALLSERIAL =>  'SERIAL',
        MEDIUMSERIAL => 'SERIAL',
        INTSERIAL =>    'SERIAL',

        TINYTEXT =>     'text',
        MEDIUMTEXT =>   'text',
        LONGTEXT =>     'text',

        LONGBLOB =>     'blob',

        DATETIME =>     'DATETIME',
        DATE     =>     'DATETIME',
    };

    $self->_adjust_schema;

    return $self;

}

#################################
# General SQLite Schema Helpers #
#################################

sub _sqlite_create_table {
    my ($self, $table) = @_;
    return scalar Bugzilla->dbh->selectrow_array(
        "SELECT sql FROM sqlite_master WHERE name = ? AND type = 'table'",
        undef, $table);
}

sub _sqlite_table_lines {
    my $self = shift;
    my $table_sql = $self->_sqlite_create_table(@_);
    $table_sql =~ s/\n*\)$//s;
    # The $ makes this work even if people some day add crazy stuff to their
    # schema like multi-column foreign keys.
    return split(/,\s*$/m, $table_sql);
}

# This does most of the "heavy lifting" of the schema-altering functions.
sub _sqlite_alter_schema {
    my ($self, $table, $create_table, $options) = @_;

    # $create_table is sometimes an array in the form that _sqlite_table_lines
    # returns.
    if (ref $create_table) {
        $create_table = join(',', @$create_table) . "\n)";
    }

    my $dbh = Bugzilla->dbh;

    my $random = generate_random_password(5);
    my $rename_to = "${table}_$random";

    my @columns = $dbh->bz_table_columns_real($table);
    push(@columns, $options->{extra_column}) if $options->{extra_column};
    if (my $exclude = $options->{exclude_column}) {
        @columns = grep { $_ ne $exclude } @columns;
    }
    my @insert_cols = @columns;
    my @select_cols = @columns;
    if (my $rename = $options->{rename}) {
        foreach my $from (keys %$rename) {
            my $to = $rename->{$from};
            @insert_cols = map { $_ eq $from ? $to : $_ } @insert_cols;
        }
    }

    my $insert_str = join(',', @insert_cols);
    my $select_str = join(',', @select_cols);
    my $copy_sql = "INSERT INTO $table ($insert_str)"
                   . " SELECT $select_str FROM $rename_to";

    # We have to turn FKs off before doing this. Otherwise, when we rename
    # the table, all of the FKs in the other tables will be automatically
    # updated to point to the renamed table. Note that PRAGMA foreign_keys
    # can only be set outside of a transaction--otherwise it is a no-op.
    if ($dbh->bz_in_transaction) {
        die "can't alter the schema inside of a transaction";
    }
    my @sql = (
        'PRAGMA foreign_keys = OFF',
        'BEGIN EXCLUSIVE TRANSACTION',
        @{ $options->{pre_sql} || [] },
        "ALTER TABLE $table RENAME TO $rename_to",
        $create_table,
        $copy_sql,
        "DROP TABLE $rename_to",
        'COMMIT TRANSACTION',
        'PRAGMA foreign_keys = ON',
    );
}

# For finding a particular column's definition in a CREATE TABLE statement.
sub _sqlite_column_regex {
    my ($column) = @_;
    # 1 = Comma at start
    # 2 = Column name + Space
    # 3 = Definition
    # 4 = Ending comma
    return qr/(^|,)(\s\Q$column\E\s+)(.*?)(,|$)/m;
}

#############################
# Schema Setup & Alteration #
#############################

sub get_create_database_sql {
    # If we get here, it means there was some error creating the
    # database file during bz_create_database in Bugzilla::DB,
    # and we just want to display that error instead of doing
    # anything else.
    Bugzilla->dbh;
    die "Reached an unreachable point";
}

sub _get_create_table_ddl {
    my $self = shift;
    my ($table) = @_;
    my $ddl = $self->SUPER::_get_create_table_ddl(@_);

    # TheSchwartz uses its own driver to access its tables, meaning
    # that it doesn't understand "COLLATE bugzilla" and in fact
    # SQLite throws an error when TheSchwartz tries to access its
    # own tables, if COLLATE bugzilla is on them. We don't have
    # to fix this elsewhere currently, because we only create
    # TheSchwartz's tables, we never modify them.
    if ($table =~ /^ts_/) {
        $ddl =~ s/ COLLATE bugzilla//g;
    }
    return $ddl;
}

sub get_type_ddl {
    my $self = shift;
    my $def = dclone($_[0]);

    my $ddl = $self->SUPER::get_type_ddl(@_);
    if ($def->{PRIMARYKEY} and $def->{TYPE} =~ /SERIAL/i) {
        $ddl =~ s/\bSERIAL\b/integer/;
        $ddl =~ s/\bPRIMARY KEY\b/PRIMARY KEY AUTOINCREMENT/;
    }
    if ($def->{TYPE} =~ /text/i or $def->{TYPE} =~ /char/i) {
        $ddl .= " COLLATE bugzilla";
    }
    # Don't collate DATETIME fields.
    if ($def->{TYPE} eq 'DATETIME') {
        $ddl =~ s/\bDATETIME\b/text COLLATE BINARY/;
    }
    return $ddl;
}

sub get_alter_column_ddl {
    my $self = shift;
    my ($table, $column, $new_def, $set_nulls_to) = @_;
    my $dbh = Bugzilla->dbh;

    my $table_sql = $self->_sqlite_create_table($table);
    my $new_ddl = $self->get_type_ddl($new_def);
    # When we do ADD COLUMN, columns can show up all on one line separated
    # by commas, so we have to account for that.
    my $column_regex = _sqlite_column_regex($column);
    $table_sql =~ s/$column_regex/$1$2$new_ddl$4/
        || die "couldn't find $column in $table:\n$table_sql";
    my @pre_sql = $self->_set_nulls_sql(@_);
    return $self->_sqlite_alter_schema($table, $table_sql,
                                       { pre_sql => \@pre_sql });
}

sub get_add_column_ddl {
    my $self = shift;
    my ($table, $column, $definition, $init_value) = @_;
    # SQLite can use the normal ADD COLUMN when:
    # * The column isn't a PK
    if ($definition->{PRIMARYKEY}) {
        if ($definition->{NOTNULL} and $definition->{TYPE} !~ /SERIAL/i) {
            die "You can only add new SERIAL type PKs with SQLite";
        }
        my $table_sql = $self->_sqlite_new_column_sql(@_);
        # This works because _sqlite_alter_schema will exclude the new column
        # in its INSERT ... SELECT statement, meaning that when the "new"
        # table is populated, it will have AUTOINCREMENT values generated
        # for it.
        return $self->_sqlite_alter_schema($table, $table_sql);
    }
    # * The column has a default one way or another. Either it
    #   defaults to NULL (it lacks NOT NULL) or it has a DEFAULT
    #   clause. Since we also require this when doing bz_add_column (in
    #   the way of forcing an init_value for NOT NULL columns with no
    #   default), we first set the init_value as the default and then
    #   alter the column.
    if ($definition->{NOTNULL} and !defined $definition->{DEFAULT}) {
        my %with_default = %$definition;
        $with_default{DEFAULT} = $init_value;
        my @pre_sql =
            $self->SUPER::get_add_column_ddl($table, $column, \%with_default);
        my $table_sql = $self->_sqlite_new_column_sql(@_);
        return $self->_sqlite_alter_schema($table, $table_sql,
            { pre_sql => \@pre_sql, extra_column => $column });
    }

    return $self->SUPER::get_add_column_ddl(@_);
}

sub _sqlite_new_column_sql {
    my ($self, $table, $column, $def) = @_;
    my $table_sql = $self->_sqlite_create_table($table);
    my $new_ddl = $self->get_type_ddl($def);
    my $new_line = "\t$column\t$new_ddl";
    $table_sql =~ s/^(CREATE TABLE \w+ \()/$1\n$new_line,/s
        || die "Can't find start of CREATE TABLE:\n$table_sql";
    return $table_sql;
}

sub get_drop_column_ddl {
    my ($self, $table, $column) = @_;
    my $table_sql = $self->_sqlite_create_table($table);
    my $column_regex = _sqlite_column_regex($column);
    $table_sql =~ s/$column_regex/$1/
        || die "Can't find column $column: $table_sql";
    # Make sure we don't end up with a comma at the end of the definition.
    $table_sql =~ s/,\s+\)$/\n)/s;
    return $self->_sqlite_alter_schema($table, $table_sql,
                                       { exclude_column => $column });
}

sub get_rename_column_ddl {
    my ($self, $table, $old_name, $new_name) = @_;
    my $table_sql = $self->_sqlite_create_table($table);
    my $column_regex = _sqlite_column_regex($old_name);
    $table_sql =~ s/$column_regex/$1\t$new_name\t$3$4/
        || die "Can't find $old_name: $table_sql";
    my %rename = ($old_name => $new_name);
    return $self->_sqlite_alter_schema($table, $table_sql,
                                       { rename => \%rename });
}

################
# Foreign Keys #
################

sub get_add_fks_sql {
    my ($self, $table, $column_fks) = @_;
    my @clauses = $self->_sqlite_table_lines($table);
    my @add = $self->_column_fks_to_ddl($table, $column_fks);
    push(@clauses, @add);
    return $self->_sqlite_alter_schema($table, \@clauses);
}

sub get_drop_fk_sql {
    my ($self, $table, $column, $references) = @_;
    my @clauses = $self->_sqlite_table_lines($table);
    my $fk_name = $self->_get_fk_name($table, $column, $references);

    my $line_re = qr/^\s+CONSTRAINT $fk_name /s;
    grep { $line_re } @clauses
        or die "Can't find $fk_name: " . join(',', @clauses);
    @clauses = grep { $_ !~ $line_re } @clauses;

    return $self->_sqlite_alter_schema($table, \@clauses);
}


1;