NAME
    HTML::FormFu::Model::DBIC - Integrate HTML::FormFu with DBIx::Class

SYNOPSIS
    Example of typical use in a Catalyst controller:

        sub edit : Chained {
            my ( $self, $c ) = @_;
        
            my $form = $c->stash->{form};
            my $book = $c->stash->{book};
        
            if ( $form->submitted_and_valid ) {
            
                # update dbic row with submitted values from form
            
                $form->model->update( $book );
            
                $c->response->redirect( $c->uri_for('view', $book->id) );
                return;
            }
            elsif ( !$form->submitted ) {
            
                # use dbic row to set form's default values
            
                $form->model->default_values( $book );
            }
        
            return;
        }

SETUP
    For the form object to be able to access your DBIx::Class schema, it
    needs to be placed on the form stash, with the name "schema".

    This is easy if you're using Catalyst-Controller-HTML-FormFu, as you can
    set this up to happen in your Catalyst app's config file.

    For example, if your model is named "MyApp::Model::Corp", you would set
    this (in Config::General format):

        <Controller::HTML::FormFu>
            <model_stash>
                schema Corp
            </model_stash>
        </Controller::HTML::FormFu>

    Or if your app's config file is in YAML format:

        'Controller::HTML::FormFu':
            model_stash:
                schema: Corp

METHODS
  default_values
    Arguments: $dbic_row, [\%config]

    Return Value: $form

        $form->model->default_values( $dbic_row );

    Set a form's default values from the database, to allow a user to edit
    them.

  update
    Arguments: [$dbic_row], [\%config]

    Return Value: $dbic_row

        $form->model->update( $dbic_row );

    Update the database with the submitted form values.

  create
    Arguments: [\%config]

    Return Value: $dbic_row

        my $dbic_row = $form->model->create( {resultset => 'Book'} );

    Like "update", but doesn't require a $dbic_row argument.

    You need to ensure the DBIC schema is available on the form stash - see
    "SYNOPSIS" for an example config.

    The "resultset" must be set either in the method arguments, or the form
    or block's "model_config".

    An example of setting the ResultSet name on a Form:

        ---
        model_config:
          resultset: FooTable
    
        elements:
          # [snip]

  options_from_model
    Populates a multi-valued field with values from the database.

    This method should not be called directly, but is called for you during
    "$form->process" by fields that inherit from
    HTML::FormFu::Element::_Group. This includes:

    HTML::FormFu::Element::Select
    HTML::FormFu::Element::Checkboxgroup
    HTML::FormFu::Element::Radiogroup
    HTML::FormFu::Element::ComboBox

    To use you must set the appropriate "resultset" on the element
    "model_config":

        element:
          - type: Select
            name: foo
            model_config:
              resultset: TableClass

BUILDING FORMS
  single table
    To edit the values in a row with no related rows, the field names simply
    have to correspond to the database column names.

    For the following DBIx::Class schema:

        package MySchema::Book;
        use base 'DBIx::Class';
    
        __PACKAGE__->load_components(qw/ Core /);
    
        __PACKAGE__->table("book");
    
        __PACKAGE__->add_columns(
            id     => { data_type => "INTEGER" },
            title  => { data_type => "TEXT" },
            author => { data_type => "TEXT" },
            blurb  => { data_type => "TEXT" },
        );
    
        __PACKAGE__->set_primary_key("id");
    
        1;

    A suitable form for this might be:

        elements:
          - type: Text
            name: title
      
          - type: Text
            name: author
      
          - type: Textarea
            name: blurb

  might_have and has_one relationships
    Set field values from a related row with a "might_have" or "has_one"
    relationship by placing the fields within a Block (or any element that
    inherits from Block, such as Fieldset) with its "nested_name" in
    HTML::FormFu set to the relationship name.

    For the following DBIx::Class schemas:

        package MySchema::Book;
        use base 'DBIx::Class';
    
        __PACKAGE__->load_components(qw/ Core /);
    
        __PACKAGE__->table("book");
    
        __PACKAGE__->add_columns(
            id    => { data_type => "INTEGER" },
            title => { data_type => "TEXT" },
        );
    
        __PACKAGE__->set_primary_key("id");
    
        __PACKAGE__->might_have( review => 'MySchema::Review', 'book' );
    
        1;


        package MySchema::Review;
        use base 'DBIx::Class';
    
        __PACKAGE__->load_components(qw/ Core /);
    
        __PACKAGE__->table("review");
    
        __PACKAGE__->add_columns(
            id          => { data_type => "INTEGER" },
            book        => { data_type => "INTEGER", is_nullable => 1 },
            review_text => { data_type => "TEXT" },
        );
    
        __PACKAGE__->set_primary_key("book");
    
        __PACKAGE__->belongs_to( book => 'MySchema::Book' );
    
        1;

    A suitable form for this would be:

        elements:
          - type: Text
            name: title
      
          - type: Block
            nested_name: review
            elements:
              - type: Textarea
                name: review_text

    For "might_have" and "has_one" relationships, you generally shouldn't
    need to have a field for the related table's primary key, as DBIx::Class
    will handle retrieving the correct row automatically.

    You can also set a "has_one" or "might_have" relationship using a multi
    value field like Select.

        elements:
          - type: Text
            name: title
      
          - type: Select
            nested: review
            model_config:
              resultset: Review

    This will load all reviews into the select field. If you select a review
    from that list, a current relationship to a review is removed and the
    new one is added. This requires that the primary key of the "Review"
    table and the foreign key do not match.

  has_many and many_to_many relationships
    The general principle is the same as for "might_have" and "has_one"
    above, except you should use a Repeatable element instead of a Block,
    and it needs to contain a Hidden field corresponding to the foreign key.

    The Repeatable block's nested_name must be set to the name of the
    relationship.

    The Repeable block's increment_field_names must be true (which is the
    default value).

    The Repeable block's counter_name must be set to the name of a Hidden
    field, which is placed outside of the Repeatable block. This field is
    used to store a count of the number of repetitions of the Repeatable
    block were created. When the form is submitted, this value is used
    during "$form->process" to ensure the form is rebuilt with the correct
    number of repetitions.

    For the following DBIx::Class schemas:

        package MySchema::Book;
        use base 'DBIx::Class';
    
        __PACKAGE__->load_components(qw/ Core /);
    
        __PACKAGE__->table("book");
    
        __PACKAGE__->add_columns(
            id    => { data_type => "INTEGER" },
            title => { data_type => "TEXT" },
        );
    
        __PACKAGE__->set_primary_key("id");
    
        __PACKAGE__->has_many( review => 'MySchema::Review', 'book' );
    
        1;


        package MySchema::Review;
        use base 'DBIx::Class';
    
        __PACKAGE__->load_components(qw/ Core /);
    
        __PACKAGE__->table("review");
    
        __PACKAGE__->add_columns(
            book        => { data_type => "INTEGER" },
            review_text => { data_type => "TEXT" },
        );
    
        __PACKAGE__->set_primary_key("book");
    
        __PACKAGE__->belongs_to( book => 'MySchema::Book' );
    
        1;

    A suitable form for this would be:

        elements:
          - type: Text
            name: title
      
          - type: Hidden
            name: review_count
      
          - type: Repeatable
            nested_name: review
            counter_name: review_count
            elements:
              - type: Hidden
                name: book
          
              - type: Textarea
                name: review_text

  many_to_many selection
    To select / deselect rows from a "many_to_many" relationship, you must
    use a multi-valued element, such as a Checkboxgroup or a Select with
    multiple set.

    The field's name must be set to the name of the "many_to_many"
    relationship.

   default_column
    If you want to search / associate the related table by a column other
    it's primary key, set "$field->model_config->{default_column}".

        ---
        element:
            - type: Checkboxgroup
              name: authors
              model_config:
                default_column: foo

   link_values
    If you want to set columns on the link table you can do so if you add a
    "link_values" attribute to "model_config":

        ---
        element:
            - type: Checkboxgroup
              name: authors
              model_config:
                link_values:
                  foo: bar

   additive
    The default implementation will first remove all related objects and set
    the new ones (see
    <http://search.cpan.org/perldoc?DBIx::Class::Relationship::Base#set_$rel
    >). If you want to add the selected objects to the current set of
    objects set "additive" in the "model_config".

        ---
        element:
            - type: Checkboxgroup
              name: authors
              model_config:
                additive: 1
                options_from_model: 0

    "options_from_model" is set to 0 because it will try to fetch all
    objects from the result class "Authors" if "model_config" is specified
    without a "resultset" attribute.)

COMMON ARGUMENTS
    The following items are supported in the optional "config" hash-ref
    argument to the methods default_values, update and create.

    base
        If you want the method to process a particular Block element, rather
        than the whole form, you can pass the element as a "base" argument.

            $form->default_values(
                $row,
                {
                    base => $formfu_element,
                },
            );

    nested_base
        If you want the method to process a particular Block element by
        name, you can pass the name as an argument.

            $form->default_values(
                $row,
                {
                    nested_base => 'foo',
                }'
            );

CONFIGURATION
  Config options for fields
    The following items are supported as "model_config" options on form
    fields.

    accessor
        If set, "accessor" will be used as a method-name accessor on the
        "DBIx::Class" row object, instead of using the field name.

    ignore_if_empty
        If the submitted value is blank, no attempt will be made to save it
        to the database.

    null_if_empty
        If the submitted value is blank, save it as NULL to the database.
        Normally an empty string is saved as NULL when its corresponding
        field is numeric, and as an empty string when its corresponding
        field is a text field. This option is useful for changing the
        default behavior for text fields.

    delete_if_empty
        Useful for editing a "might_have" related row containing only one
        field.

        If the submitted value is blank, the related row is deleted.

        For the following DBIx::Class schemas:

            package MySchema::Book;
            use base 'DBIx::Class';
    
            __PACKAGE__->load_components(qw/ Core /);
    
            __PACKAGE__->table("book");
    
            __PACKAGE__->add_columns(
                id    => { data_type => "INTEGER" },
                title => { data_type => "TEXT" },
            );
    
            __PACKAGE__->set_primary_key("id");
    
            __PACKAGE__->might_have( review => 'MySchema::Review', 'book' );
    
            1;


            package MySchema::Review;
            use base 'DBIx::Class';
    
            __PACKAGE__->load_components(qw/ Core /);
    
            __PACKAGE__->table("review");
    
            __PACKAGE__->add_columns(
                book        => { data_type => "INTEGER" },
                review_text => { data_type => "TEXT" },
            );
    
            __PACKAGE__->set_primary_key("book");
    
            __PACKAGE__->belongs_to( book => 'MySchema::Book' );
    
            1;

        A suitable form for this would be:

            elements:
              - type: Text
                name: title
      
              - type: Block
                nested_name: review
                elements:
                  - type: Text
                    name: review_text
                    model_config:
                      delete_if_empty: 1

    label
        To use a column value for a form field's label.

  Config options for fields within a Repeatable block
    delete_if_true
        Intended for use on a Checkbox field.

        If the checkbox is checked, the following occurs: for a has-many
        relationship, the related row is deleted; for a many-to-many
        relationship, the relationship link is removed.

        An example of use might be:

            elements:
              - type: Text
                name: title
      
              - type: Hidden
                name: review_count
      
              - type: Repeatable
                nested_name: review
                counter_name: review_count
                elements:
                  - type: Hidden
                    name: book
          
                  - type: Textarea
                    name: review_text
          
                  - type: Checkbox
                    name: delete_review
                    label: 'Delete Review?'
                    model_config:
                      delete_if_true: 1

        Note: make sure the name of this field does not clash with one of
        your DBIx::Class::Row method names (e.g. "delete") - see "CAVEATS".

  Config options for Repeatable blocks
    empty_rows
        For a Repeatable block corresponding to a has-many or many-to-many
        relationship, to allow the user to insert new rows, set "empty_rows"
        to the number of extra repetitions you wish added to the end of the
        Repeatable block.

    new_rows_max
        Set to the maximum number of new rows that a Repeatable block is
        allowed to add.

        If not set, it will fallback to the value of "empty_rows".

  Config options for options_from_model
    The column used for the element values is set with the "model_config"
    value "id_column" - or if not set, the table's primary column is used.

        element:
          - type: Select
            name: foo
            model_config:
              resultset: TableClass
              id_column: pk_col

    The column used for the element labels is set with the "model_config"
    value "label_column" - or if not set, the first text/varchar column
    found in the table is used - or if one is not found, the "id_column" is
    used instead.

        element:
          - type: Select
            name: foo
            model_config:
              resultset: TableClass
              label_column: label_col

    To pass the database label values via the form's localization object,
    set "localize_label"

        element:
          - type: Select
            name: foo
            model_config:
              localize_label: 1

    You can set a "condition", which will be passed as the 1st argument to
    "search" in DBIx::Class::ResultSet.

        element:
          - type: Select
            name: foo
            model_config:
              resultset: TableClass
              condition:
                type: is_foo

    You can set a "condition_from_stash", which will be passed as the 1st
    argument to "search" in DBIx::Class::ResultSet.

    "key" is the column-name to be passed to search, and "stash_key" is the
    name of a key on the form stash from which the value to be passed to
    search is found.

        element:
          - type: Select
            name: foo
            model_config:
              resultset: TableClass
              condition_from_stash:
                key: stash_key

    Is comparable to:

        $form->element({
            type => 'Select',
            name => 'foo',
            model_config => {
                resultset => 'TableClass',
                condition => {
                    key => $form->stash->{stash_key}
                }
            }
        })

    You can set "attributes", which will be passed as the 2nd argument to
    "search" in DBIx::Class::ResultSet.

FAQ
  Add extra values not in the form
    To update values to the database which weren't submitted to the form,
    you can first add them to the form with add_valid.

        my $passwd = generate_passwd();
    
        $form->add_valid( passwd => $passwd );
    
        $form->model->update( $row );

    "add_valid" works for fieldnames that don't exist in the form.

  Set a field read only
    You can make a field read only. The value of such fields cannot be
    changed by the user even if they submit a value for it.

      $field->model_config->{read_only} = 1;
  
      - Name: field
        model_config:
          read_only: 1

    See HTML::FormFu::Element::Label.

CAVEATS
    To ensure your column's inflators and deflators are called, we have to
    get / set values using their named methods, and not with "get_column" /
    "set_column".

    Because of this, beware of having column names which clash with
    DBIx::Class built-in method-names, such as "delete". - It will have
    obviously undesirable results!

REMOVED METHODS
  new_empty_row
    See "empty_rows" in "Config options for Repeatable blocks" instead.

  new_empty_row_multi
    See "new_rows_max" in "Config options for Repeatable blocks" instead.

  Range constraint
    See "empty_rows" in "Config options for Repeatable blocks" instead.

SUPPORT
    Project Page:

    <http://code.google.com/p/html-formfu/>

    Mailing list:

    <http://lists.scsys.co.uk/cgi-bin/mailman/listinfo/html-formfu>

    Mailing list archives:

    <http://lists.scsys.co.uk/pipermail/html-formfu/>

BUGS
    Please submit bugs / feature requests to
    <http://code.google.com/p/html-formfu/issues/list> (preferred) or
    <http://rt.perl.org>.

GITHUB REPOSITORY
    This module's sourcecode is maintained in a git repository at
    <git://github.com/fireartist/HTML-FormFu-Model-DBIC.git>

    The project page is
    <https://github.com/fireartist/HTML-FormFu-Model-DBIC>

SEE ALSO
    HTML::FormFu, DBIx::Class, Catalyst::Controller::HTML::FormFu

AUTHOR
    Carl Franks

CONTRIBUTORS
    Based on the code of "DBIx::Class::HTML::FormFu", which was contributed
    to by:

    Adam Herzog

    Daisuke Maki

    Mario Minati

COPYRIGHT AND LICENSE
    Copyright (C) 2007 by Carl Franks

    Based on the original source code of DBIx::Class::HTMLWidget, copyright
    Thomas Klausner.

    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself, either Perl version 5.8.8 or, at
    your option, any later version of Perl 5 you may have available.

