NAME

       Catmandu::Validator - Namespace for packages that can validate records in Catmandu.

SYNOPSIS

           use Catmandu::Validator::Simple;

           my $validator = Catmandu::Validator::Simple->new(
               handler => sub {
                   $data = shift;
                   return "error" unless $data->{title} =~ m/good title/;
                   return;
               }
           );

           if ( $validator->is_valid($hashref) ) {
               save_record_in_database($hashref);
           } else {
               reject_form($validator->last_errors);
           }

           my $validator = Catmandu::Validator::Simple->new(
               handler => sub { ...},
               error_callback => sub {
                   my ($data, $errors) = @_;
                   print "Validation errors for record $data->{_id}:\n";
                   print "$_\n" for @{$errors};
               }
           };

           my $validated_arrayref = $validator->validate($arrayref);

           $validator->validate($iterator, {
               after_callback => sub {
                   my ($record, $errors) = @_;
                   if ($errors) {
                       add_to_failure_report($rec, $errors);
                       #omit the invalid record from the result
                       return undef;
                   }
                   return $rec;
               }
           })->each( sub {
               my $record = shift;
               publish_record($record);
           });

DESCRIPTION

       A Catmandu::Validator is a base class for Perl packages that can validate data.

METHODS

   new()
       Create a new Catmandu::Validator.

   new( after_callback => \&callback )
       The after_callback is called after each record has been validated.  The callback function
       should take $hashref to each data record, and $arrayref to list of validation errors for
       the record as arguments.

   new( error_field => $field_name )
       If the error_field parameter is set, then during validation each record that fails
       validation will get an extra field added containing an arrayref to the validation errors.
       The name of the key will be the value passed or '_validation_errors' if 1 is passed. By
       default it is not set.

   is_valid( \%hash )
       Validates a single record. Returns 1 success and 0 on failure. Information about the
       validation errors can be retrieved with the "last_errors()" method.

   validate( \%hash )
   validate( $iterator )
   validate( \@array )
       Validates a single record or multiple records in an iterator or an array. Returns
       validated records in the same type of container for multiple records or the record itself
       for a single record. The default behaviour is to return the records that passed validation
       unchanged and omit the invalid records.  This behaviour can be changed by setting the
       after_callback or the error_field in the constructor. Returns undef on validation failure
       for single records.

   last_errors()
       Returns arrayref of errors from the record that was last validated if that record failed
       validation or undef if there were no errors.

   valid_count()
       Returns the number of valid records from last validate operation.

   invalid_count()
       Returns the number of invalid records from the last validate operation.

SEE ALSO

       Catmandu::Validator::Simple, Catmandu::Iterable