Bric::Util::Pref(3p)  User Contributed Perl Documentation Bric::Util::Pref(3p)



NAME
       Bric::Util::Pref - Interface to Bricolage preferences.

VERSION
       $LastChangedRevision$

DATE
       $LastChangedDate: 2006-03-18 01:26:34 +0100 (Sat, 18 Mar 2006) $

SYNOPSIS
         use Bric::Util::Pref;

         # Constructors.
         my $pref = Bric::Util::Pref->new($init);
         $pref = Bric::Util::Pref->lookup({ id => $id });
         $pref = Bric::Util::Pref->lookup({ name => $name });
         my @prefs = Bric::Util::Pref->list($params);

         # Class Methods.
         my @pref_ids = Bric::Util::Pref->list_ids($params);
         my $meths = Bric::Util::Pref->my_meths;
         my @meths = Bric::Util::Pref->my_meths(1);
         # Fetch a value from the cache.
         my $val = Bric::Util::Pref->lookup_val($name);

         # Instance Methods
         my $id = $pref->get_id;
         my $name = $pref->get_name;
         my $desc = $pref->get_description;
         my $default = $pref->get_default;
         my $opt_type = $pref->get_opt_type;
         my $val_name = $pref->get_val_name;

         # Get a list of available value options.
         my @opts = $pref->get_opts;
         my $opts_ref = $pref->get_opts_href;

         # Get and set the value.
         my $value = $pref->get_value;
         $pref = $pref->set_value($value);

         # Save the pref.
         $pref = $pref->save;

DESCRIPTION
       This is the central interface for managing Bricolage application
       preferences. It should scale when we later decide to add user and user
       group preferences. Right now it'll just support those global
       application preferences that we deem necessary for the application to
       work, such as Time Zone.

INTERFACE
   Constructors
       my $pref = Bric::Util::Pref->lookup({ id => $id })
       my $pref = Bric::Util::Pref->lookup({ name => $name })
           Looks up and instantiates a new Bric::Util::Pref object based on
           the Bric::Util::Pref object ID or name passed. If $id or $name is
           not found in the database, lookup() returns undef.

           Throws:

           o   Too many Bric::Dist::Util::Pref objects found.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to connect to database.

           o   Unable to select column into arrayref.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           Side Effects: If $id is found, populates the new Bric::Util::Pref
           object with data from the database before returning it.

           Notes: NONE.

       my (@prefs || $prefs_aref) = Bric::Util::Pref->list($params)
           Returns a list or anonymous array of Bric::Util::Pref objects based
           on the search parameters passed via an anonymous hash. The
           supported lookup keys are:

           id  Preference ID. May use "ANY" for a list of possible values.

           name
               Preference name. May use "ANY" for a list of possible values.

           description
               Preference description. May use "ANY" for a list of possible
               values.

           default
               Preference default value. May use "ANY" for a list of possible
               values.

           value
               Value to which preference is set. May use "ANY" for a list of
               possible values.

           val_name
               Name of the value. May use "ANY" for a list of possible values.

           manual
               Boolean indicating whether a value can be manually entered by
               the user, rather than selected from a list. May use "ANY" for a
               list of possible values.

           can_be_overridden
               Boolean indicating whether or not users can override the global
               preference value. May use "ANY" for a list of possible values.

           opt_type
               The preference option type. May use "ANY" for a list of
               possible values.

           grp_id
               The ID of a Bric::Util::Grp object with which prefereneces may
               be associated.  May use "ANY" for a list of possible values.

           Throws:

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to connect to database.

           o   Unable to select column into arrayref.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           Side Effects: Populates each Bric::Util::Pref object with data from
           the database before returning them all.

           Notes: NONE.

   Destructors
       $pref->DESTROY
           Dummy method to prevent wasting time trying to AUTOLOAD DESTROY.

           Throws: NONE.

           Side Effects: NONE.

           Notes: NONE.

   Public Class Methods
       my (@pref_ids || $pref_ids_aref) = Bric::Util::Pref->list_ids($params)
           Returns a list or anonymous array of Bric::Util::Pref object IDs
           based on the search criteria passed via an anonymous hash. The
           supported lookup keys are the same as those for list().

           Throws:

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to connect to database.

           o   Unable to select column into arrayref.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           Side Effects: NONE.

           Notes: NONE.

       Bric::Util::Pref->use_user_prefs(1)
           Returns true if "lookup_val()" will return the value of a user
           preference, and false if it will not. Pass in a true or false value
           to change enable or disable the returning of user preferences by
           "lookup_val()".

           Throws: NONE.

           Side Effects: NONE.

           Notes: NONE.

       my $val = Bric::Util::Pref->lookup_val($pref_name)
           Looks up and returns the value of a preference without the expense
           of instantiating an object. Plus, it uses caching to keep it quick
           - the cache changes only when a value changes. If
           "use_user_prefs()" returns true and a user is currently logged in,
           then the value of the preference for that user will be returned.
           Otherwise, the global preference will be returned.

           Throws:

           o   Unable to instantiate create cache.

           o   Unable to populate preference cache.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           o   Unable to get cache value.

           Side Effects: See &$load_cache().

           Notes: See &$load_cache().

       $meths = Bric::Util::Pref->my_meths
       (@meths || $meths_aref) = Bric::Util::Pref->my_meths(TRUE)
       my (@meths || $meths_aref) = Bric::Util::Pref->my_meths(0, TRUE)
           Returns an anonymous hash of introspection data for this object. If
           called with a true argument, it will return an ordered list or
           anonymous array of introspection data. If a second true argument is
           passed instead of a first, then a list or anonymous array of
           introspection data will be returned for properties that uniquely
           identify an object (excluding "id", which is assumed).

           Each hash key is the name of a property or attribute of the object.
           The value for a hash key is another anonymous hash containing the
           following keys:

           name
               The name of the property or attribute. Is the same as the hash
               key when an anonymous hash is returned.

           disp
               The display name of the property or attribute.

           get_meth
               A reference to the method that will retrieve the value of the
               property or attribute.

           get_args
               An anonymous array of arguments to pass to a call to get_meth
               in order to retrieve the value of the property or attribute.

           set_meth
               A reference to the method that will set the value of the
               property or attribute.

           set_args
               An anonymous array of arguments to pass to a call to set_meth
               in order to set the value of the property or attribute.

           type
               The type of value the property or attribute contains. There are
               only three types:

               short
               date
               blob
           len If the value is a 'short' value, this hash key contains the
               length of the field.

           search
               The property is searchable via the list() and list_ids()
               methods.

           req The property or attribute is required.

           props
               An anonymous hash of properties used to display the property or
               attribute. Possible keys include:

               type
                   The display field type. Possible values are

                   text
                   textarea
                   password
                   hidden
                   radio
                   checkbox
                   select
               length
                   The Length, in letters, to display a text or password
                   field.

               maxlength
                   The maximum length of the property or value - usually
                   defined by the SQL DDL.

           rows
               The number of rows to format in a textarea field.

           cols
               The number of columns to format in a textarea field.

           vals
               An anonymous hash of key/value pairs reprsenting the values and
               display names to use in a select list.

           Throws: NONE.

           Side Effects: NONE.

           Notes: NONE.

   Public Instance Methods
       my $id = $pref->get_id
           Returns the ID of the Bric::Util::Pref object.

           Throws:

           o   Bad AUTOLOAD method format.

           o   Cannot AUTOLOAD private methods.

           o   Access denied: READ access for field 'id' required.

           o   No AUTOLOAD method.

           Side Effects: NONE.

           Notes: If the Bric::Util::Pref object has been instantiated via the
           new() constructor and has not yet been "save"d, the object will not
           yet have an ID, so this method call will return undef.

       my $name = $pref->get_name
           Returns preference name.

           Throws:

           o   Bad AUTOLOAD method format.

           o   Cannot AUTOLOAD private methods.

           o   Access denied: READ access for field 'name' required.

           o   No AUTOLOAD method.

           Side Effects: NONE.

           Notes: NONE.

       my $description = $pref->get_description
           Returns preference description.

           Throws:

           o   Bad AUTOLOAD method format.

           o   Cannot AUTOLOAD private methods.

           o   Access denied: READ access for field 'description' required.

           o   No AUTOLOAD method.

           Side Effects: NONE.

           Notes: NONE.

       my $default = $pref->get_default
           Returns preference default.

           Throws:

           o   Bad AUTOLOAD method format.

           o   Cannot AUTOLOAD private methods.

           o   Access denied: READ access for field 'default' required.

           o   No AUTOLOAD method.

           Side Effects: NONE.

           Notes: NONE.

       my $value = $pref->get_value
           Returns the preference value.

           Throws:

           o   Bad AUTOLOAD method format.

           o   Cannot AUTOLOAD private methods.

           o   Access denied: READ access for field 'value' required.

           o   No AUTOLOAD method.

           Side Effects: NONE.

           Notes: NONE.

       $self = $pref->set_value($value)
           Sets the preference value.

           Throws:

           o   Incorrect number of args to _set().

           Side Effects: NONE.

           Notes: NONE.

       my $can_be_overridden = $pref->get_can_be_overridden
           Returns a boolean indicating whether the value can be overridden on
           a per-user basis.

           Throws:

           o   Bad AUTOLOAD method format.

           o   Cannot AUTOLOAD private methods.

           o   Access denied: READ access for field 'can_be_overridden'
               required.

           o   No AUTOLOAD method.

           Side Effects: NONE.

           Notes: NONE.

       $self = $pref->set_can_be_overridden($can_be_overridden)
           Sets whether the value can be overridden on a per-user basis.

           Throws:

           o   Incorrect number of args to _set().

           Side Effects: NONE.

           Notes: NONE.

       my $opt_type = $pref->get_opt_type
           Returns preference opt_type ('select', 'radio', 'text', ...).

           Throws:

           o   Bad AUTOLOAD method format.

           o   Cannot AUTOLOAD private methods.

           o   Access denied: READ access for field 'opt_type' required.

           o   No AUTOLOAD method.

           Side Effects: NONE.

           Notes: NONE.

       my $val_name = $pref->get_val_name
           Returns preference value's descriptive name. Note that if you've
           set the value, this method will return an incorrect value unless
           and until you instantiate the object again using lookup() or
           list().

           Throws:

           o   Problems retrieving fields.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to select column into arrayref.

           o   Incorrect number of args to _set().

           Side Effects: NONE.

           Notes: NONE.

       my (@opts || $opts_aref) = $pref->get_opts
           Returns a list or anonymous array of options available for filling
           in the value of this preference.

           Throws:

           o   Bric::_get() - Problems retrieving fields.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to connect to database.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           o   Incorrect number of args to Bric::_set().

           o   Bric::set() - Problems setting fields.

           Side Effects: NONE.

           Notes: NONE.

       my $opts_href = $pref->get_opts_href
           Returns a hashref of options available for filling in the value of
           this preference. The hash keys are the options, and the values are
           their descriptions.

           Throws:

           o   Bric::_get() - Problems retrieving fields.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to connect to database.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           o   Incorrect number of args to Bric::_set().

           o   Bric::set() - Problems setting fields.

           Side Effects: NONE.

           Notes: NONE.

       $self = $pref->save
           Saves any changes to the Bric::Util::Pref object. Returns $self on
           success and undef on failure.

           Throws:

           o   Bric::_get() - Problems retrieving fields.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to execute SQL statement.

           o   Unable to instantiate preference cache.

           o   Unable to populate preference cache.

           o   Unable to set cache value.

           Side Effects: NONE.

           Notes: NONE.

PRIVATE
   Private Class Methods
       NONE.

   Private Instance Methods
       NONE.

   Private Functions
       my $pref_aref = &$get_em( $pkg, $params )
       my $pref_ids_aref = &$get_em( $pkg, $params, 1 )
           Function used by lookup() and list() to return a list of
           Bric::Util::Pref objects or, if called with an optional third
           argument, returns a list of Bric::Util::Pref object IDs (used by
           list_ids()).

           Throws:

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to connect to database.

           o   Unable to select column into arrayref.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           Side Effects: NONE.

           Notes: NONE.

       my $action = &$get_opts($self)
           Queries this preference's value options from the database.

           Throws:

           o   Bric::_get() - Problems retrieving fields.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to select column into arrayref.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           o   Incorrect number of args to Bric::_set().

           o   Bric::set() - Problems setting fields.

           Side Effects: NONE.

           Notes: NONE.

       $cache = &$load_cache()
           Loads all the preference keys and values into a Cache::FileCache
           object.

           Throws:

           o   Unable to instantiate preference cache.

           o   Unable to populate preference cache.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           Side Effects: NONE.

           Notes: Uses Bric::App::Cache for persistence across processes.

       my $cache = &$cache_val($name, $value)
           Sets a value in the cache.

           Throws:

           o   Unable to instantiate preference cache.

           o   Unable to populate preference cache.

           o   Unable to connect to database.

           o   Unable to prepare SQL statement.

           o   Unable to execute SQL statement.

           o   Unable to bind to columns to statement handle.

           o   Unable to fetch row from statement handle.

           o   Unable to set cache value.

           Side Effects: See &$load_cache().

           Notes: See &$load_cache().

NOTES
       NONE.

AUTHOR
       David Wheeler <david@justatheory.com>

SEE ALSO
       Bric



perl v5.12.2                      2006-03-17              Bric::Util::Pref(3p)
