lib/DBIx/Class/DeploymentHandler/Dad.pm

   1 package DBIx::Class::DeploymentHandler::Dad;
   2
   3 use Moose;
   4 use Method::Signatures::Simple;
   5 require DBIx::Class::Schema;    # loaded for type constraint
   6 use Carp::Clan '^DBIx::Class::DeploymentHandler';
   7
   8 has schema => (
   9   isa      => 'DBIx::Class::Schema',
  10   is       => 'ro',
  11   required => 1,
  12   handles => ['schema_version'],
  13 );
  14
  15 has backup_directory => (
  16   isa => 'Str',
  17   is  => 'ro',
  18   predicate  => 'has_backup_directory',
  19 );
  20
  21 has to_version => (
  22   is         => 'ro',
  23   lazy_build => 1,
  24 );
  25
  26 sub _build_to_version { $_[0]->schema->schema_version }
  27
  28 method install {
  29   croak 'Install not possible as versions table already exists in database'
  30     if $self->version_storage_is_installed;
  31
  32   my $ddl = $self->deploy;
  33
  34   $self->add_database_version({
  35     version     => $self->to_version,
  36     ddl         => $ddl,
  37   });
  38 }
  39
  40 sub upgrade {
  41   my $self = shift;
  42   while ( my $version_list = $self->next_version_set ) {
  43     my ($ddl, $upgrade_sql) = @{$self->upgrade_single_step($version_list)||[]};
  44
  45     $self->add_database_version({
  46       version     => $version_list->[-1],
  47       ddl         => $ddl,
  48       upgrade_sql => $upgrade_sql,
  49     });
  50   }
  51 }
  52
  53 sub downgrade {
  54   my $self = shift;
  55   while ( my $version_list = $self->previous_version_set ) {
  56     $self->downgrade_single_step($version_list);
  57
  58     # do we just delete a row here?  I think so but not sure
  59     $self->delete_database_version({ version => $version_list->[-1] });
  60   }
  61 }
  62
  63 method backup { $self->storage->backup($self->backup_directory) }
  64
  65 __PACKAGE__->meta->make_immutable;
  66
  67 1;
  68
  69 =pod
  70
  71 =attr schema
  72
  73 The L<DBIx::Class::Schema> (B<required>) that is used to talk to the database
  74 and generate the DDL.
  75
  76 =attr backup_directory
  77
  78 The directory that backups are stored in
  79
  80 =attr to_version
  81
  82 The version (defaults to schema's version) to migrate the database to
  83
  84 =method install
  85
  86  $dh->install
  87
  88 Deploys the current schema into the database.  Populates C<version_storage> with
  89 C<version> and C<ddl>.
  90
  91 B<Note>: you typically need to call C<< $dh->prepare_install >> before you call
  92 this method.
  93
  94 B<Note>: you cannot install on top of an already installed database
  95
  96 =method upgrade
  97
  98  $dh->upgrade
  99
 100 Upgrades the database one step at a time till L</next_version_set>
 101 returns C<undef>.  Each upgrade step will add a C<version>, C<ddl>, and
 102 C<upgrade_sql> to the version storage (if C<ddl> and/or C<upgrade_sql> are
 103 returned from L</upgrade_single_step>.
 104
 105 =method downgrade
 106
 107  $dh->downgrade
 108
 109 Downgrades the database one step at a time till L</previous_version_set>
 110 returns C<undef>.  Each downgrade step will delete a C<version>from the
 111 version storage.
 112
 113 =method backup
 114
 115  $dh->backup
 116
 117 Simply calls backup on the C<< $schema->storage >>, passing in
 118 C<< $self->backup_directory >> as an argument.  Please test yourself before
 119 assuming it will work.
 120
 121 =head1 METHODS THAT ARE REQUIRED IN SUBCLASSES
 122
 123 =head2 deploy
 124
 125 See L<DBIx::Class::DeploymentHandler::HandlesDeploy/deploy>.
 126
 127 =head2 version_storage_is_installed
 128
 129 See L<DBIx::Class::DeploymentHandler::HandlesVersionStorage/version_storage_is_installed>.
 130
 131 =head2 add_database_version
 132
 133 See L<DBIx::Class::DeploymentHandler::HandlesVersionStorage/add_database_version>.
 134
 135 =head2 delete_database_version
 136
 137 See L<DBIx::Class::DeploymentHandler::HandlesVersionStorage/delete_database_version>.
 138
 139 =head2 next_version_set
 140
 141 See L<DBIx::Class::DeploymentHandler::HandlesVersioning/next_version_set>.
 142
 143 =head2 previous_version_set
 144
 145 See L<DBIx::Class::DeploymentHandler::HandlesVersioning/previous_version_set>.
 146
 147 =head2 upgrade_single_step
 148
 149 See L<DBIx::Class::DeploymentHandler::HandlesDeploy/upgrade_single_step>.
 150
 151 =head2 downgrade_single_step
 152
 153 See L<DBIx::Class::DeploymentHandler::HandlesDeploy/downgrade_single_step>.
 154
 155 =head1 ORTHODOX METHODS
 156
 157 These methods are not actually B<required> as things will probably still work
 158 if you don't implement them, but if you want your subclass to get along with
 159 other subclasses (or more likely, tools made to use another subclass), you
 160 should probably implement these too, even if they are no-ops.
 161
 162 =head2 database_version
 163
 164 see L<DBIx::Class::DeploymentHandler::HandlesVersionStorage/database_version>
 165
 166 =head2 prepare_install
 167
 168 see L<DBIx::Class::DeploymentHandler::HandlesDeploy/prepare_install>
 169
 170 =head2 prepare_resultsource_install
 171
 172 see L<DBIx::Class::DeploymentHandler::HandlesDeploy/prepare_resultsouce_install>
 173
 174 =head2 install_resultsource
 175
 176 see L<DBIx::Class::DeploymentHandler::HandlesDeploy/install_resultsource>
 177
 178 =head2 prepare_upgrade
 179
 180 see L<DBIx::Class::DeploymentHandler::HandlesDeploy/prepare_upgrade>
 181
 182 =head2 prepare_downgrade
 183
 184 see L<DBIx::Class::DeploymentHandler::HandlesDeploy/prepare_downgrade>
 185
 186 =back
 187
 188 =head2 SUBCLASSING
 189
 190 All of the methods mentioned in L</METHODS THAT ARE REQUIRED IN SUBCLASSES> and
 191 L</ORTHODOX METHODS> can be implemented in any fashion you choose.  In the
 192 spirit of code reuse I have used roles to implement them in my two subclasses,
 193 L<DBIx::Class::DeploymentHandler> and
 194 L<DBIx::Class::DeploymentHandler::Deprecated>, but you are free to implement
 195 them entirely in a subclass if you so choose to.
 196
 197 For in-depth documentation on how methods are supposed to work, see the roles
 198 L<DBIx::Class::DeploymentHandler::HandlesDeploy>,
 199 L<DBIx::Class::DeploymentHandler::HandlesVersioning>, and
 200 L<DBIx::Class::DeploymentHandler::HandlesVersionStorage>.
 201
 202 __END__
 203
 204 vim: ts=2 sw=2 expandtab