2 use base qw(Class::Accessor::Fast Class::Data::Inheritable);
3 use UNIVERSAL::require;
8 use Maypole::Constants;
13 use File::MMagic::XS qw(:compat);
15 our $VERSION = '2.11';
16 our $mmagic = File::MMagic::XS->new();
18 # proposed privacy conventions:
19 # - no leading underscore - public to custom application code and plugins
20 # - single leading underscore - private to the main Maypole stack - *not*
22 # - double leading underscore - private to the current package
26 Maypole - MVC web application framework
30 The canonical example used in the Maypole documentation is the beer database:
36 # choose a frontend, initialise the config object, and load a plugin
37 use Maypole::Application qw/Relationship/;
39 # get the empty config object created by Maypole::Application
40 my $config = __PACKAGE__->config;
43 $config->uri_base("http://localhost/beerdb");
44 $config->template_root("/path/to/templates");
45 $config->rows_per_page(10);
46 $config->display_tables([qw/beer brewery pub style/]);
49 $config->relationships([
50 "a brewery produces beers",
51 "a style defines beers",
52 "a pub has beers on handpumps",
56 BeerDB::Brewery->untaint_columns( printable => [qw/name notes url/] );
57 BeerDB::Pub->untaint_columns( printable => [qw/name notes url/] );
58 BeerDB::Style->untaint_columns( printable => [qw/name notes/] );
59 BeerDB::Beer->untaint_columns(
60 printable => [qw/abv name price notes/],
61 integer => [qw/style brewery score/],
66 __PACKAGE__->setup("dbi:SQLite:t/beerdb.db");
72 This documents the Maypole request object. See the L<Maypole::Manual>, for a
73 detailed guide to using Maypole.
75 Maypole is a Perl web application framework similar to Java's struts. It is
76 essentially completely abstracted, and so doesn't know anything about
77 how to talk to the outside world.
79 To use it, you need to create a driver package which represents your entire
80 application. This is the C<BeerDB> package used as an example in the manual.
82 This needs to first use L<Maypole::Application> which will make your package
83 inherit from the appropriate platform driver such as C<Apache::MVC> or
84 C<CGI::Maypole>. Then, the driver calls C<setup>. This sets up the model classes
85 and configures your application. The default model class for Maypole uses
86 L<Class::DBI> to map a database to classes, but this can be changed by altering
87 configuration (B<before> calling setup.)
90 =head1 DOCUMENTATION AND SUPPORT
92 Note that some details in some of these resources may be out of date.
96 =item The Maypole Manual
98 The primary documentation is the Maypole manual. This lives in the
99 C<Maypole::Manual> pod documents included with the distribution.
103 Individual packages within the distribution contain (more or less) detailed
104 reference documentation for their API.
108 There are two mailing lists - maypole-devel and maypole-users - see
109 http://maypole.perl.org/?MailingList
111 =item The Maypole Wiki
113 The Maypole wiki provides a useful store of extra documentation -
114 http://maypole.perl.org
116 In particular, there's a FAQ (http://maypole.perl.org/?FAQ) and a cookbook
117 (http://maypole.perl.org/?Cookbook). Again, certain information on these pages
120 =item Web applications with Maypole
122 A tutorial written by Simon Cozens for YAPC::EU 2005 -
123 http://www.droogs.org/perl/maypole/maypole-tutorial.pdf [228KB].
125 =item A Database-Driven Web Application in 18 Lines of Code
127 By Paul Barry, published in Linux Journal, March 2005.
129 http://www.linuxjournal.com/article/7937
131 "From zero to Web-based database application in eight easy steps".
133 Maypole won a 2005 Linux Journal Editor's Choice Award
134 (http://www.linuxjournal.com/article/8293) after featuring in this article.
136 =item Build Web apps with Maypole
138 By Simon Cozens, on IBM's DeveloperWorks website, May 2004.
140 http://www-128.ibm.com/developerworks/linux/library/l-maypole/
142 =item Rapid Web Application Deployment with Maypole
144 By Simon Cozens, on O'Reilly's Perl website, April 2004.
146 http://www.perl.com/pub/a/2004/04/15/maypole.html
150 Some notes written by Simon Cozens. A little bit out of date, but still
151 very useful: http://www.droogs.org/perl/maypole/authentication.html
155 There's a refcard for the Maypole (and Class::DBI) APIs on the wiki -
156 http://maypole.perl.org/?CheatSheet. Probably a little out of date now - it's a
157 wiki, so feel free to fix any errors!
159 =item Plugins and add-ons
161 There are a large and growing number of plugins and other add-on modules
162 available on CPAN - http://search.cpan.org/search?query=maypole&mode=module
166 You can find a range of useful Maypole links, particularly to several thoughtful
167 blog entries, starting here: http://del.icio.us/search/?all=maypole
171 There are a couple of short reviews here:
172 http://cpanratings.perl.org/dist/Maypole
178 A couple of demos are available, sometimes with source code and configs.
182 =item http://maypole.perl.org/beerdb/
184 The standard BeerDB example, using the TT factory templates supplied in the
187 =item beerdb.riverside-cms.co.uk
189 The standard BeerDB example, running on Mason, using the factory templates
190 supplied in the L<MasonX::Maypole> distribution.
192 =item beerfb.riverside-cms.co.uk
194 A demo of L<Maypole::FormBuilder>. This site is running on the set of Mason
195 templates included in the L<Maypole::FormBuilder> distribution. See the
196 synopsis of L<Maypole::Plugin::FormBuilder> for an example driver
202 __PACKAGE__->mk_classdata($_) for qw( config init_done view_object model_classes_loaded);
204 __PACKAGE__->mk_accessors(
205 qw( params query objects model_class template_args output path
206 args action template error document_encoding content_type table
207 headers_in headers_out stash status parent)
210 __PACKAGE__->config( Maypole::Config->new() );
212 __PACKAGE__->init_done(0);
214 __PACKAGE__->model_classes_loaded(0);
216 =head1 HOOKABLE METHODS
218 As a framework, Maypole provides a number of B<hooks> - methods that are
219 intended to be overridden. Some of these methods come with useful default
220 behaviour, others do nothing by default. Hooks include:
246 sub My::App::debug {1}
248 Returns the debugging flag. Override this in your application class to
249 enable/disable debugging.
251 You can also set the C<debug> flag via L<Maypole::Application>.
253 Some packages respond to higher debug levels, try increasing it to 2 or 3.
262 Returns the L<Maypole::Config> object
266 My::App->setup($data_source, $user, $password, \%attr);
268 Initialise the Maypole application and plugins and model classes.
269 Your application should call this B<after> setting up configuration data via
272 It calls the hook C<setup_model> to setup the model. The %attr hash contains
273 options and arguments used to set up the model. See the particular model's
274 documentation. However here is the most usage of setup where
275 Maypole::Model::CDBI is the base class.
277 My::App->setup($data_source, $user, $password,
278 { options => { # These are DB connection options
283 # These are Class::DBI::Loader arguments.
289 Also, see L<Maypole::Manual::Plugins>.
298 $class->setup_model(@_);
303 Called by C<setup>. This method builds the Maypole model hierarchy.
305 A likely target for over-riding, if you need to build a customised model.
307 This method also ensures any code in custom model classes is loaded, so you
308 don't need to load them in the driver.
314 $class = ref $class if ref $class;
315 my $config = $class->config;
316 $config->model || $config->model('Maypole::Model::CDBI');
317 $config->model->require or die sprintf
318 "Couldn't load the model class %s: %s", $config->model, $@;
320 # among other things, this populates $config->classes
321 $config->model->setup_database($config, $class, @_);
323 foreach my $subclass ( @{ $config->classes } ) {
324 next if $subclass->isa("Maypole::Model::Base");
326 unshift @{ $subclass . "::ISA" }, $config->model;
329 # Load custom model code, if it exists - nb this must happen after the
330 # unshift, to allow code attributes to work, but before adopt(),
331 # in case adopt() calls overridden methods on $subclass
332 foreach my $subclass ( @{ $config->classes } ) {
333 $class->load_model_subclass($subclass) unless ($class->model_classes_loaded());
334 $config->model->adopt($subclass) if $config->model->can("adopt");
339 =item load_model_subclass($subclass)
341 This method is called from C<setup_model()>. It attempts to load the
342 C<$subclass> package, if one exists. So if you make a customized C<BeerDB::Beer>
343 package, you don't need to explicitly load it.
345 If automatic loading causes problems, Override load_model_subclass in your driver.
347 sub load_model_subclass {};
349 Or perhaps during development, if you don't want to load up custom classes, you
350 can override this method and load them manually.
354 sub load_model_subclass {
355 my ($class, $subclass) = @_;
357 my $config = $class->config;
359 # Load any external files for the model base class or subclasses
360 # (e.g. BeerDB/DBI.pm or BeerDB/Beer.pm) based on code borrowed from
361 # Maypole::Plugin::Loader and Class::DBI.
362 if ( $subclass->require ) {
363 warn "Loaded external module for '$subclass'\n" if $class->debug > 1;
365 (my $filename = $subclass) =~ s!::!/!g;
366 die "Loading '$subclass' failed: $@\n"
367 unless $@ =~ /Can\'t locate \Q$filename\E\.pm/;
368 warn "No external module for '$subclass'"
369 if $class->debug > 1;
375 Loads the view class and instantiates the view object.
377 You should not call this directly, but you may wish to override this to add
378 application-specific initialisation - see L<Maypole::Manual::Plugins>.
385 my $config = $class->config;
386 $config->view || $config->view("Maypole::View::TT");
387 $config->view->require;
388 die "Couldn't load the view class " . $config->view . ": $@" if $@;
389 $config->display_tables
390 || $config->display_tables( $class->config->tables );
391 $class->view_object( $class->config->view->new );
392 $class->init_done(1);
397 Constructs a very minimal new Maypole request object.
405 config => $class->config,
411 $self->template_args({});
420 Get/set the Maypole::View object
424 =head1 INSTANCE METHODS
432 This method sets up the class if it's not done yet, sets some defaults and
433 leaves the dirty work to C<handler_guts>.
437 # handler() has a method attribute so that mod_perl will invoke
438 # BeerDB->handler() as a method rather than a plain function
439 # BeerDB::handler() and so this inherited implementation will be
440 # found. See e.g. "Practical mod_perl" by Bekman & Cholet for
441 # more information <http://modperlbook.org/html/ch25_01.html>
442 sub handler : method {
443 # See Maypole::Workflow before trying to understand this.
444 my ($class, $req) = @_;
446 $class->init unless $class->init_done;
448 my $self = $class->new;
450 # initialise the request
451 $self->headers_out(Maypole::Headers->new);
452 $self->get_request($req);
454 $self->parse_location;
456 # hook useful for declining static requests e.g. images, or perhaps for
457 # sanitizing request parameters
458 $self->status(Maypole::Constants::OK()); # set the default
459 $self->__call_hook('start_request_hook');
460 return $self->status unless $self->status == Maypole::Constants::OK();
461 die "status undefined after start_request_hook()" unless defined
465 my $status = $self->handler_guts;
466 return $status unless $status == OK;
467 # TODO: require send_output to return a status code
474 Run Maypole sub-requests as a component of the request
476 [% request.component("/beer/view_as_component/20") %]
478 Allows you to integrate the results of a Maypole request into an existing
479 request. You'll need to set up actions and templates
480 which return fragments of HTML rather than entire pages, but once you've
481 done that, you can use the C<component> method of the Maypole request object
482 to call those actions. You may pass a query string in the usual URL style.
484 You should not fully qualify the Maypole URLs.
486 Note: any HTTP POST or URL parameters passed to the parent are not passed to the
487 component sub-request, only what is included in the url passed as an argyument
493 my ( $r, $path ) = @_;
494 my $self = bless { parent => $r, config => $r->{config}, } , ref $r;
498 $self->template_args({});
503 my $url = URI->new($path);
504 warn "path : $path\n";
505 $self->{path} = $url->path;
507 $self->params( $url->query_form_hash );
509 return $self->output;
512 sub get_template_root {
515 return $r->parent->get_template_root if $r->{parent};
516 return $self->NEXT::DISTINCT::get_template_root( $r, @_ );
522 return $r->parent->view_object if $r->{parent};
523 return $self->NEXT::DISTINCT::view_object( $r, @_ );
526 # Instead of making plugin authors use the NEXT::DISTINCT hoopla to ensure other
527 # plugins also get to call the hook, we can cycle through the application's
528 # @ISA and call them all here. Doesn't work for setup() though, because it's
529 # too ingrained in the stack. We could add a run_setup() method, but we'd break
530 # lots of existing code.
533 my ($self, $hook) = @_;
537 my $class = ref($self);
539 @plugins = @{"$class\::ISA"};
542 # this is either a custom method in the driver, or the method in the 1st
543 # plugin, or the 'null' method in the frontend (i.e. inherited from
544 # Maypole.pm) - we need to be careful to only call it once
545 my $first_hook = $self->can($hook);
548 my %seen = ( $first_hook => 1 );
550 # @plugins includes the frontend
551 foreach my $plugin (@plugins)
553 next unless my $plugin_hook = $plugin->can($hook);
554 next if $seen{$plugin_hook}++;
561 This is the main request handling method and calls various methods to handle the
562 request/response and defines the workflow within Maypole.
564 B<Currently undocumented and liable to be refactored without warning>.
568 # The root of all evil
573 $self->__load_request_model;
575 my $applicable = $self->is_model_applicable == OK;
579 # handle authentication
580 eval { $status = $self->call_authenticate };
581 if ( my $error = $@ )
583 $status = $self->call_exception($error, "authentication");
586 warn "caught authenticate error: $error";
587 return $self->debug ?
588 $self->view_object->error($self, $error) : ERROR;
591 if ( $self->debug and $status != OK and $status != DECLINED )
593 $self->view_object->error( $self,
594 "Got unexpected status $status from calling authentication" );
597 return $status unless $status == OK;
599 # We run additional_data for every request
600 $self->additional_data;
603 eval { $self->model_class->process($self) };
604 if ( my $error = $@ )
606 $status = $self->call_exception($error, "model");
609 warn "caught model error: $error";
610 return $self->debug ?
611 $self->view_object->error($self, $error) : ERROR;
615 $self->__setup_plain_template;
618 # less frequent path - perhaps output has been set to an error message
619 return OK if $self->output;
621 # normal path - no output has been generated yet
622 my $processed_view_ok = $self->__call_process_view;
624 $self->{content_type} ||= $self->__get_mime_type();
625 $self->{document_encoding} ||= "utf-8";
628 return $processed_view_ok;
632 'js' => 'text/javascript',
634 'htm' => 'text/html',
635 'html' => 'text/html',
638 sub __get_mime_type {
640 my $type = 'text/html';
641 if ($self->path =~ m/.*\.(\w{3,4})$/) {
642 $type = $filetypes{$1};
644 my $output = $self->output;
645 if (defined $output) {
646 $type = $mmagic->checktype_contents($output);
652 sub __load_request_model
655 $self->model_class( $self->config->model->class_of($self, $self->table) );
658 # is_applicable() returned false, so set up a plain template. Model processing
659 # will be skipped, but need to remove the model anyway so the template can't
661 sub __setup_plain_template
665 # It's just a plain template
666 $self->model_class(undef);
668 my $path = $self->path;
669 $path =~ s{/$}{}; # De-absolutify
672 $self->template($self->path);
675 # The model has been processed or skipped (if is_applicable returned false),
676 # any exceptions have been handled, and there's no content in $self->output
677 sub __call_process_view {
680 my $status = eval { $self->view_object->process($self) };
682 my $error = $@ || $self->{error};
685 $status = $self->call_exception($error, "view");
687 if ( $status != OK ) {
688 warn "caught view error: $error" if $self->debug;
689 return $self->debug ?
690 $self->view_object->error($self, $error) : ERROR;
699 You should only need to define this method if you are writing a new
700 Maypole backend. It should return something that looks like an Apache
701 or CGI request object, it defaults to blank.
709 Turns the backend request (e.g. Apache::MVC, Maypole, CGI) into a Maypole
710 request. It does this by setting the C<path>, and invoking C<parse_path> and
713 You should only need to define this method if you are writing a new Maypole
720 die "parse_location is a virtual method. Do not use Maypole directly; " .
721 "use Apache::MVC or similar";
724 =item start_request_hook
726 This is called immediately after setting up the basic request. The default
729 The value of C<< $r->status >> is set to C<OK> before this hook is run. Your
730 implementation can change the status code, or leave it alone.
732 After this hook has run, Maypole will check the value of C<status>. For any
733 value other than C<OK>, Maypole returns the C<status> immediately.
735 This is useful for filtering out requests for static files, e.g. images, which
736 should not be processed by Maypole or by the templating engine:
738 sub start_request_hook
742 $r->status(DECLINED) if $r->path =~ /\.jpg$/;
745 Multiple plugins, and the driver, can define this hook - Maypole will call all
746 of them. You should check for and probably not change any non-OK C<status>
749 package Maypole::Plugin::MyApp::SkipFavicon;
751 sub start_request_hook
755 # check if a previous plugin has already DECLINED this request
756 # - probably unnecessary in this example, but you get the idea
757 return unless $r->status == OK;
760 $r->status(DECLINED) if $r->path =~ /favicon\.ico/;
765 sub start_request_hook { }
769 B<This method is deprecated> as of version 2.11. If you have overridden it,
770 please override C<is_model_applicable> instead, and change the return type
771 from a Maypole:Constant to a true/false value.
773 Returns a Maypole::Constant to indicate whether the request is valid.
777 sub is_applicable { return shift->is_model_applicable(@_); }
779 =item is_model_applicable
781 Returns true or false to indicate whether the request is valid.
783 The default implementation checks that C<< $r->table >> is publicly
784 accessible and that the model class is configured to handle the
789 sub is_model_applicable {
792 # Establish which tables should be processed by the model
793 my $config = $self->config;
795 $config->ok_tables || $config->ok_tables( $config->display_tables );
797 $config->ok_tables( { map { $_ => 1 } @{ $config->ok_tables } } )
798 if ref $config->ok_tables eq "ARRAY";
800 my $ok_tables = $config->ok_tables;
802 # Does this request concern a table to be processed by the model?
803 my $table = $self->table;
807 if (exists $ok_tables->{$table})
814 warn "We don't have that table ($table).\n"
815 . "Available tables are: "
816 . join( ",", keys %$ok_tables )
817 if $self->debug and not $ok_tables->{$table};
822 # Is the action public?
823 my $action = $self->action;
824 return OK if $self->model_class->is_public($action);
826 warn "The action '$action' is not applicable to the table '$table'"
834 Called immediately after C<start_request_hook()>.
836 This method should return a session, which will be stored in the request's
837 C<session> attribute.
839 The default method is empty.
847 Called immediately after C<get_session>.
849 This method should return a user, which will be stored in the request's C<user>
852 The default method is empty.
858 =item call_authenticate
860 This method first checks if the relevant model class
861 can authenticate the user, or falls back to the default
862 authenticate method of your Maypole application.
866 sub call_authenticate
870 # Check if we have a model class with an authenticate() to delegate to
871 return $self->model_class->authenticate($self)
872 if $self->model_class and $self->model_class->can('authenticate');
874 # Interface consistency is a Good Thing -
875 # the invocant and the argument may one day be different things
876 # (i.e. controller and request), like they are when authenticate()
877 # is called on a model class (i.e. model and request)
878 return $self->authenticate($self);
883 Returns a Maypole::Constant to indicate whether the user is authenticated for
886 The default implementation returns C<OK>
890 sub authenticate { return OK }
895 This model is called to catch exceptions, first after authenticate, then after
896 processing the model class, and finally to check for exceptions from the view
899 This method first checks if the relevant model class
900 can handle exceptions the user, or falls back to the default
901 exception method of your Maypole application.
907 my ($self, $error, $when) = @_;
909 # Check if we have a model class with an exception() to delegate to
910 if ( $self->model_class && $self->model_class->can('exception') )
912 my $status = $self->model_class->exception( $self, $error, $when );
913 return $status if $status == OK;
916 return $self->exception($error, $when);
922 This method is called if any exceptions are raised during the authentication or
923 model/view processing. It should accept the exception as a parameter and return
924 a Maypole::Constant to indicate whether the request should continue to be
930 my ($self, $error, $when) = @_;
931 if (ref $self->view_object && $self->view_object->can("report_error") and $self->debug) {
932 $self->view_object->report_error($self, $error, $when);
938 =item additional_data
940 Called before the model processes the request, this method gives you a chance to
941 do some processing for each request, for example, manipulating C<template_args>.
945 sub additional_data { }
949 Sends the output and additional headers to the user.
954 die "send_output is a virtual method. Do not use Maypole directly; use Apache::MVC or similar";
962 =head2 Path processing and manipulation
968 Returns the request path
972 Parses the request path and sets the C<args>, C<action> and C<table>
973 properties. Calls C<preprocess_path> before parsing path and setting properties.
981 # Previous versions unconditionally set table, action and args to whatever
982 # was in @pi (or else to defaults, if @pi is empty).
983 # Adding preprocess_path(), and then setting table, action and args
984 # conditionally, broke lots of tests, hence this:
985 $self->$_(undef) for qw/action table args/;
987 $self->preprocess_path;
988 $self->path || $self->path('frontpage');
990 my @pi = grep {length} split '/', $self->path;
993 $self->table || $self->table(shift @pi);
994 $self->action || $self->action( shift @pi or 'index' );
995 $self->args || $self->args(\@pi);
998 =item preprocess_path
1000 Sometimes when you don't want to rewrite or over-ride parse_path but
1001 want to rewrite urls or extract data from them before it is parsed.
1003 This method is called after parse_location has populated the request
1004 information and before parse_path has populated the model and action
1005 information, and is passed the request object.
1007 You can set action, args or table in this method and parse_path will
1008 then leave those values in place or populate them if not present
1012 sub preprocess_path { };
1014 =item make_path( %args or \%args or @args )
1016 This is the counterpart to C<parse_path>. It generates a path to use
1017 in links, form actions etc. To implement your own path scheme, just override
1018 this method and C<parse_path>.
1020 %args = ( table => $table,
1022 additional => $additional, # optional - generally an object ID
1025 \%args = as above, but a ref
1027 @args = ( $table, $action, $additional ); # $additional is optional
1029 C<id> can be used as an alternative key to C<additional>.
1031 C<$additional> can be a string, an arrayref, or a hashref. An arrayref is
1032 expanded into extra path elements, whereas a hashref is translated into a query
1043 if (@_ == 1 and ref $_[0] and ref $_[0] eq 'HASH')
1047 elsif ( @_ > 1 and @_ < 4 )
1049 $args{table} = shift;
1050 $args{action} = shift;
1051 $args{additional} = shift;
1058 do { die "no $_" unless $args{$_} } for qw( table action );
1060 my $additional = $args{additional} || $args{id};
1066 # if $additional is a href, make_uri() will transform it into a query
1067 @add = (ref $additional eq 'ARRAY') ? @$additional : ($additional);
1070 my $uri = $r->make_uri($args{table}, $args{action}, @add);
1072 return $uri->as_string;
1077 =item make_uri( @segments )
1079 Make a L<URI> object given table, action etc. Automatically adds
1082 If the final element in C<@segments> is a hash ref, C<make_uri> will render it
1089 my ($r, @segments) = @_;
1091 my $query = (ref $segments[-1] eq 'HASH') ? pop(@segments) : undef;
1093 my $base = $r->config->uri_base;
1096 my $uri = URI->new($base);
1097 $uri->path_segments($uri->path_segments, grep {length} @segments);
1099 my $abs_uri = $uri->abs('/');
1100 $abs_uri->query_form($query) if $query;
1106 Turns post data and query string paramaters into a hash of C<params>.
1108 You should only need to define this method if you are writing a new Maypole
1115 die "parse_args() is a virtual method. Do not use Maypole directly; ".
1116 "use Apache::MVC or similar";
1119 =item get_template_root
1121 Implementation-specific path to template root.
1123 You should only need to define this method if you are writing a new Maypole
1124 backend. Otherwise, see L<Maypole::Config/"template_root">
1130 =head2 Request properties
1136 Returns the perl package name that will serve as the model for the
1137 request. It corresponds to the request C<table> attribute.
1142 Get/set a list of model objects. The objects will be accessible in the view
1145 If the first item in C<$self-E<gt>args> can be C<retrieve()>d by the model
1146 class, it will be removed from C<args> and the retrieved object will be added to
1147 the C<objects> list. See L<Maypole::Model> for more information.
1151 $self->template_args->{foo} = 'bar';
1153 Get/set a hash of template variables.
1157 A place to put custom application data. Not used by Maypole itself.
1161 Get/set the template to be used by the view. By default, it returns
1162 C<$self-E<gt>action>
1167 Get/set a request error
1171 Get/set the response output. This is usually populated by the view class. You
1172 can skip view processing by setting the C<output>.
1176 The table part of the Maypole request path
1180 The action part of the Maypole request path
1184 A list of remaining parts of the request path after table and action
1190 A L<Maypole::Headers> object containing HTTP headers for the request
1194 A L<HTTP::Headers> object that contains HTTP headers for the output
1196 =item document_encoding
1198 Get/set the output encoding. Default: utf-8.
1202 Get/set the output content type. Default: text/html
1206 Returns the protocol the request was made with, i.e. https
1211 die "get_protocol is a virtual method. Do not use Maypole directly; use Apache::MVC or similar";
1216 =head2 Request parameters
1218 The source of the parameters may vary depending on the Maypole backend, but they
1219 are usually populated from request query string and POST data.
1221 Maypole supplies several approaches for accessing the request parameters. Note
1222 that the current implementation (via a hashref) of C<query> and C<params> is
1223 likely to change in a future version of Maypole. So avoid direct access to these
1226 $r->{params}->{foo} # bad
1227 $r->params->{foo} # better
1229 $r->{query}->{foo} # bad
1230 $r->query->{foo} # better
1232 $r->param('foo') # best
1238 An accessor (get or set) for request parameters. It behaves similarly to
1239 CGI::param() for accessing CGI parameters, i.e.
1241 $r->param # returns list of keys
1242 $r->param($key) # returns value for $key
1243 $r->param($key => $value) # returns old value, sets to new value
1249 my ($self, $key) = (shift, shift);
1251 return keys %{$self->params} unless defined $key;
1253 return unless exists $self->params->{$key};
1255 my $val = $self->params->{$key};
1259 my $new_val = shift;
1260 $self->params->{$key} = $new_val;
1263 return ref $val ? @$val : ($val) if wantarray;
1265 return ref $val ? $val->[0] : $val;
1271 Returns a hashref of request parameters.
1273 B<Note:> Where muliple values of a parameter were supplied, the C<params> value
1274 will be an array reference.
1278 Alias for C<params>.
1282 =head3 Utility methods
1286 =item redirect_request
1288 Sets output headers to redirect based on the arguments provided
1290 Accepts either a single argument of the full url to redirect to, or a hash of
1293 $r->redirect_request('http://www.example.com/path');
1297 $r->redirect_request(protocol=>'https', domain=>'www.example.com', path=>'/path/file?arguments', status=>'302', url=>'..');
1299 The named parameters are protocol, domain, path, status and url
1301 Only 1 named parameter is required but other than url, they can be combined as
1302 required and current values (from the request) will be used in place of any
1303 missing arguments. The url argument must be a full url including protocol and
1304 can only be combined with status.
1308 sub redirect_request {
1309 die "redirect_request is a virtual method. Do not use Maypole directly; use Apache::MVC or similar";
1312 =item redirect_internal_request
1316 sub redirect_internal_request {
1321 =item make_random_id
1323 returns a unique id for this request can be used to prevent or detect repeat
1328 # Session and Repeat Submission Handling
1329 sub make_random_id {
1330 use Maypole::Session;
1331 return Maypole::Session::generate_unique_id();
1336 =head1 SEQUENCE DIAGRAMS
1338 See L<Maypole::Manual::Workflow> for a detailed discussion of the sequence of
1339 calls during processing of a request. This is a brief summary:
1343 BeerDB Maypole::Model::CDBI
1347 || setup_model | setup_database() creates
1348 ||------+ | a subclass of the Model
1349 |||<----+ | for each table
1351 ||| setup_database | |
1352 |||--------------------->|| 'create' *
1353 ||| ||----------> $subclass
1355 ||| load_model_subclass | |
1356 foreach |||------+ ($subclass) | |
1357 $subclass ||||<----+ | require |
1358 ||||--------------------------------------->|
1360 ||| adopt($subclass) | |
1361 |||--------------------->|| |
1366 || | new | view_object: e.g.
1367 ||---------------------------------------------> Maypole::View::TT
1379 BeerDB Model $subclass view_object
1382 o-------->| new | | |
1383 |-----> r:BeerDB | | |
1387 | ||-----+ parse_location | | |
1390 | ||-----+ start_request_hook | | |
1393 | ||-----+ get_session | | |
1396 | ||-----+ get_user | | |
1399 | ||-----+ handler_guts | | |
1401 | ||| class_of($table) | | |
1402 | |||------------------------->|| | |
1403 | ||| $subclass || | |
1404 | |||<-------------------------|| | |
1406 | |||-----+ is_model_applicable| | |
1409 | |||-----+ call_authenticate | | |
1412 | |||-----+ additional_data | | |
1415 | |||--------------------------------->|| fetch_objects
1423 | |||------------------------------------------->|| template
1427 | || send_output | | |
1431 <------------------|| | | |
1442 There's more documentation, examples, and information on our mailing lists
1443 at the Maypole web site:
1445 L<http://maypole.perl.org/>
1447 L<Maypole::Application>, L<Apache::MVC>, L<CGI::Maypole>.
1451 Maypole is currently maintained by Aaron Trevena.
1453 =head1 AUTHOR EMERITUS
1455 Simon Cozens, C<simon#cpan.org>
1457 Simon Flack maintained Maypole from 2.05 to 2.09
1459 Sebastian Riedel, C<sri#oook.de> maintained Maypole from 1.99_01 to 2.04
1463 Sebastian Riedel, Danijel Milicevic, Dave Slack, Jesse Sheidlower, Jody Belka,
1464 Marcus Ramberg, Mickael Joanne, Randal Schwartz, Simon Flack, Steve Simms,
1465 Veljko Vidovic and all the others who've helped.
1469 You may distribute this code under the same terms as Perl itself.
1477 =item register_cleanup($coderef)
1479 Analogous to L<Apache>'s C<register_cleanup>. If an Apache request object is
1480 available, this call simply redispatches there. If not, the cleanup is
1481 registered in the Maypole request, and executed when the request is
1484 This method is only useful in persistent environments, where you need to ensure
1485 that some code runs when the request finishes, no matter how it finishes (e.g.
1486 after an unexpected error).
1493 sub register_cleanup
1495 my ($self, $cleanup) = @_;
1497 die "register_cleanup() is an instance method, not a class method"
1499 die "Cleanup must be a coderef" unless ref($cleanup) eq 'CODE';
1501 if ($self->can('ar') && $self->ar)
1503 $self->ar->register_cleanup($cleanup);
1507 push @_cleanups, $cleanup;
1515 while (my $cleanup = shift @_cleanups)
1517 eval { $cleanup->() };
1520 warn "Error during request cleanup: $@";