X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCatalyst%2FManual%2FCookbook.pod;h=2a7f3fae88559381e558962ee794cdd8cb489c90;hb=e63948476024f865b8e84967ffe71681e90f2a4c;hp=0ed84d35a1d21a00b46e12ecff0d5b4680e7024e;hpb=145074c2e045b36a52cefcfded0908b91013f9ea;p=catagits%2FCatalyst-Runtime.git diff --git a/lib/Catalyst/Manual/Cookbook.pod b/lib/Catalyst/Manual/Cookbook.pod index 0ed84d3..2a7f3fa 100644 --- a/lib/Catalyst/Manual/Cookbook.pod +++ b/lib/Catalyst/Manual/Cookbook.pod @@ -10,20 +10,24 @@ Yummy code like your mum used to bake! =head2 Force debug screen -You can force Catalyst to display the debug screen at the end of the request by -placing a die() call in the _end action. +You can force Catalyst to display the debug screen at the end of the +request by placing a C call in the C action. - __PACKAGE__->action( - '!end' => sub { - my ( $self, $c ) = @_; - die "testing"; - } - ); + sub end : Private { + my ( $self, $c ) = @_; + die "forced debug"; + } If you're tired of removing and adding this all the time, you -can easily add a condition. for example: +can add a condition in the C action: + + sub end : Private { + my ( $self, $c ) = @_; + die "forced debug" if $c->req->params->{dump_info}; + } - die "Testing" if $c->param->{dump_info}; +Then just add to your query string C<"&dump_info=1">, or the like, +to force debug output. =head2 Disable statistics @@ -35,7 +39,7 @@ statistics in your debug messages. =head2 Scaffolding Scaffolding is very simple with Catalyst. -Just use Catalyst::Model::CDBI::CRUD as baseclass. +Just use Catalyst::Model::CDBI::CRUD as your base class. # lib/MyApp/Model/CDBI.pm package MyApp::Model::CDBI; @@ -60,45 +64,22 @@ Just use Catalyst::Model::CDBI::CRUD as baseclass. root => '/home/joeuser/myapp/root' ); - __PACKAGE__->action( - 'table' => sub { - my ( $self, $c ) = @_; - $c->form( optional => [ MyApp::Model::CDBI::Table->columns ] ); - $c->forward('MyApp::Model::CDBI::Table'); - } - ); + sub my_table : Global { + my ( $self, $c ) = @_; + $c->form( optional => [ MyApp::Model::CDBI::Table->columns ] ); + $c->forward('MyApp::Model::CDBI::Table'); + } 1; -Modify the $c->form() parameters to match your needs, and don't forget to copy -the templates. ;) +Modify the $c->form() parameters to match your needs, and don't forget +to copy the templates into the template root. Can't find the templates? +They were in the CRUD model distribution, so you can do B from the CPAN shell to find them. -=head2 Serving static files and CSS as text/css +Other Scaffolding modules are in development at the time of writing. -If you want to serve static content (like images, txt or CSS) via Catalyst, -then all you need is the plugin Catalyst::Plugin::Static as well as a small -regex to set the MIME type for CSS to text/css. - - # lib/MyApp.pm - package MyApp; - - use strict; - use Catalyst qw/-Debug Static/; - - __PACKAGE__->action( - - '!default' => sub { - my ( $self, $c ) = @_; - $c->serve_static; - }, - - '/^.*\.css$/' => sub { - my ( $self, $c ) = @_; - $c->serve_static('text/css'); - }, - ); - -=head2 Uploads with Catalyst +=head2 Single file upload with Catalyst To implement uploads in Catalyst you need to have a HTML form similiar to this: @@ -109,42 +90,83 @@ this: -It's very important not to forget enctype="multipart/form-data" in form, -if it's not there, uploads just don't work. +It's very important not to forget C in +the form. Catalyst Controller module 'upload' action: - MyApp->action( - - 'upload' => sub { - my ($self, $c) = @_; - if ($c->req->parameters->{form_submit} eq 'yes') { - my $filename = $c->req->parameters->{my_file}; - if ($filename) { - my $fh = $c->req->uploads->{$filename}->{fh}; - open(NEW_FILE, ">/tmp/$filename") or die - "Can't open file for writing: $!"; - while ($fh->read(my $buf, 32768)) { - print NEW_FILE $buf; - } - close(NEW_FILE); + sub upload : Global { + my ($self, $c) = @_; + + if ( $c->request->parameters->{form_submit} eq 'yes' ) { + + if ( my $upload = $c->request->upload('my_file') ) { + + my $filename = $upload->filename; + my $target = "/tmp/upload/$filename"; + + unless ( $upload->link_to($target) || $upload->copy_to($target) ) { + die( "Failed to copy '$filename' to '$target': $!" ); } } - $c->stash->{template} = 'upload_form.tt'; - $c->forward('MyApp::V::View'); - }, - ); + } + + $c->stash->{template} = 'file_upload.html'; + } + +=head2 Multiple file upload with Catalyst + +Code for uploading multiple files from one form needs a few changes: + +The form should have this basic structure: + +
+ +
+
+
+ +
+ +And in the Controller: + + sub upload : Local { + my ($self, $c) = @_; + + if ( $c->request->parameters->{form_submit} eq 'yes' ) { + + for my $field ( $c->req->upload ) { + + my $upload = $c->req->upload($field); + my $filename = $upload->filename; + my $target = "/tmp/upload/$filename"; + + unless ( $upload->link_to($target) || $upload->copy_to($target) ) { + die( "Failed to copy '$filename' to '$target': $!" ); + } + } + } + + $c->stash->{template} = 'file_upload.html'; + } + +Creq->upload)> loops automatically over all file +input fields and gets input names. After that is basic file saving code, +just like in single file upload. -If you want to upload bigger files than 1MB, then just add to your Controller -module: +Notice: Cing might not be what you want to do, when an error +occurs, but it works as an example. A better idea would be to store +error C<$!> in $c->stash->{error} and show a custom error template +displaying this message. - $CGI::Simple::POST_MAX = 1048576000; +For more information about uploads and usable methods look at +L and L. =head2 Authentication with Catalyst::Plugin::Authentication::CDBI There are (at least) two ways to implement authentication with this plugin: 1) only checking username and password -2) checking username, password and the roles the user has +2) checking username, password, and the roles the user has For both variants you'll need the following code in your MyApp package: @@ -156,54 +178,58 @@ For both variants you'll need the following code in your MyApp package: 'user_class' is a Class::DBI class for your users table. 'user_field' tells which field is used for username lookup (might be -email, first name, surname etc). +email, first name, surname etc.). 'password_field' is, well, password field in your table and by default password is stored in plain text. Authentication::CDBI looks for 'user' and 'password' fields in table, if they're not defined in the config. -In PostgreSQL users table might be something like: +In PostgreSQL, the users table might be something like: -CREATE TABLE users ( - user_id serial, - name varchar(100), - surname varchar(100), - password varchar(100), - email varchar(100), - primary key(user_id) -); + CREATE TABLE users ( + user_id serial, + name varchar(100), + surname varchar(100), + password varchar(100), + email varchar(100), + primary key(user_id) + ); We'll discuss the first variant for now: -1. user:password login / auth without roles +1. user:password login/auth without roles -To log in a user you might use a action like this: +To log in a user you might use an action like this: - '?login' => sub { + sub login : Local { my ($self, $c) = @_; if ($c->req->params->{username}) { $c->session_login($c->req->params->{username}, - $c->req->params->{password} ); + $c->req->params->{password} ); if ($c->req->{user}) { $c->forward('?restricted_area'); } } - }, + } + +This action should not go in your MyApp class...if it does, it will +conflict with the built-in method of the same name. Instead, put it +in a Controller class. $c->req->params->{username} and $c->req->params->{password} are html -form parameters from a login form. If login succeeds, then $c->req->{user} -contains the username of the authenticated user. +form parameters from a login form. If login succeeds, then +$c->req->{user} contains the username of the authenticated user. -If you want to remember the users login status inbetween further requests, -then just use the $c->session_login method, Catalyst will create a session -id, session cookie and automatically append session id to all urls. So -all you have to do, is just check $c->req->{user} where needed. +If you want to remember the user's login status in between further +requests, then just use the C<$c-Esession_login> method. Catalyst will +create a session id and session cookie and automatically append session +id to all urls. So all you have to do is just check $c->req->{user} +where needed. -To log out user, just call $c->session_logout. +To log out a user, just call $c->session_logout. -Now lets take a look at the second variant: -2. user:password login / auth with roles +Now let's take a look at the second variant: +2. user:password login/auth with roles -To use roles you need to add to MyApp->config in the 'authentication' -section following parameters: +To use roles you need to add the following parameters to MyApp->config in the 'authentication' section: role_class => 'MyApp::M::MyApp::Roles', user_role_class => 'MyApp::M::MyApp::UserRoles', @@ -212,77 +238,93 @@ section following parameters: Corresponding tables in PostgreSQL could look like this: -CREATE TABLE roles ( - role_id serial, - name varchar(100), - primary key(role_id) -); - -CREATE TABLE user_roles ( - user_role_id serial, - user_id int, - role_id int, - primary key(user_role_id), - foreign key(user_id) references users(user_id), - foreign key(role_id) references roles(role_id) -); - -The 'roles' table is a list of role names and the 'user_role' table is used for -the user -> role lookup. - -Now if a logged in user wants to see a location which is allowed only for -people with 'admin' role then in you controller you can check it with: - - '?add' => sub { + CREATE TABLE roles ( + role_id serial, + name varchar(100), + primary key(role_id) + ); + + CREATE TABLE user_roles ( + user_role_id serial, + user_id int, + role_id int, + primary key(user_role_id), + foreign key(user_id) references users(user_id), + foreign key(role_id) references roles(role_id) + ); + +The 'roles' table is a list of role names and the 'user_role' table is +used for the user -> role lookup. + +Now if a logged-in user wants to see a location which is allowed only +for people with an 'admin' role, in your controller you can check it +with: + + sub add : Local { my ($self, $c) = @_; if ($c->roles(qw/admin/)) { $c->req->output("Your account has the role 'admin.'"); } else { - $c->req->output("You're not allowed to be here"); + $c->req->output("You're not allowed to be here."); } - }, + } -One thing you might need is to forward non-authenticated users to login -form, if they try to access restricted areas. If you want to do this -controller-wide (if you have one controller for admin section) then it's -best to add user check to '!begin' action: +One thing you might need is to forward non-authenticated users to a login +form if they try to access restricted areas. If you want to do this +controller-wide (if you have one controller for your admin section) then it's +best to add a user check to a '!begin' action: - '!begin' => sub { + sub begin : Private { my ($self, $c) = @_; unless ($c->req->{user}) { $c->req->action(undef); ## notice this!! $c->forward('?login'); } - }, - -Pay attention to $c->req->action(undef). This is needed, because of the -way $c->forward works - forward to login gets called, but after that -Catalyst executes anyway the action defined in the uri (eg. if you tried to -watch /add, then first '!begin' forwards to '?login', but after that -anyway '?add' is executed). So $c->req->action(undef) undefines any -actions that were to be called and forwards user where we want him/her + } + +Pay attention to $c->req->action(undef). This is needed because of the +way $c->forward works - C to C gets called, but after that +Catalyst will still execute the action defined in the URI (e.g. if you +tried to go to C, then first 'begin' will forward to 'login', but after +that 'add' will nonetheless be executed). So $c->req->action(undef) undefines any +actions that were to be called and forwards the user where we want him/her to be. -And this is all you need to do, isn't Catalyst wonderful? +And this is all you need to do. +=head2 Pass-through login (and other actions) + +An easy way of having assorted actions that occur during the processing of +a request that are orthogonal to its actual purpose - logins, silent +commands etc. Provide actions for these, but when they're required for +something else fill e.g. a form variable __login and have a sub begin like so: + +sub begin : Private { + my ($self, $c) = @_; + foreach my $action (qw/login docommand foo bar whatever/) { + if ($c->req->params->{"__${action}"}) { + $c->forward($action); + } + } +} =head2 How to use Catalyst without mod_perl Catalyst applications give optimum performance when run under mod_perl. -However sometimes mod_perl is not an option, and running under CGI is just too -slow. There are two alternatives to mod_perl that give reasonable -performance: FastCGI and PersistentPerl. +However sometimes mod_perl is not an option, and running under CGI is +just too slow. There's also an alternative to mod_perl that gives +reasonable performance named FastCGI. B -To quote from L: "FastCGI is a language independent, -scalable, extension to CGI that provides high performance without the -limitations of specific server APIs." Web server support is provided for -Apache in the form of C and there is Perl support in the C -module. To convert a CGI Catalyst application to FastCGI one needs to -initialize an C object and loop while the C method -returns zero. The following code shows how it is done - and it also works as -a normal, single-shot CGI script. +To quote from L: "FastCGI is a language +independent, scalable, extension to CGI that provides high performance +without the limitations of specific server APIs." Web server support +is provided for Apache in the form of C and there is Perl +support in the C module. To convert a CGI Catalyst application +to FastCGI one needs to initialize an C object and loop +while the C method returns zero. The following code shows how +it is done - and it also works as a normal, single-shot CGI script. #!/usr/bin/perl use strict; @@ -291,27 +333,24 @@ a normal, single-shot CGI script. my $request = FCGI::Request(); while ($request->Accept() >= 0) { - my $output; - { - local(*STDOUT); - open( STDOUT, '>', \$output ); - MyApp->run; - } - $output =~ s!^HTTP/\d+.\d+ \d\d\d.*?\n!!s; - print $output; + MyApp->run; } -Any initialization code should be included outside the request-accept loop. +Any initialization code should be included outside the request-accept +loop. -There is one little complication, which is that Crun> outputs a -complete HTTP response including the status line (e.g.: "C"). -FastCGI just wants a set of headers, so the sample code captures the output -and drops the first line if it is an HTTP status line (note: this may change). +There is one little complication, which is that Crun> outputs a +complete HTTP response including the status line (e.g.: +"C"). +FastCGI just wants a set of headers, so the sample code captures the +output and drops the first line if it is an HTTP status line (note: +this may change). -The Apache C module is provided by a number of Linux distros and -is straightforward to compile for most Unix-like systems. The module provides -a FastCGI Process Manager, which manages FastCGI scripts. You configure your -script as a FastCGI script with the following Apache configuration directives: +The Apache C module is provided by a number of Linux +distros and is straightforward to compile for most Unix-like systems. +The module provides a FastCGI Process Manager, which manages FastCGI +scripts. You configure your script as a FastCGI script with the +following Apache configuration directives: AddHandler fastcgi-script fcgi @@ -326,60 +365,161 @@ or: C provides a number of options for controlling the FastCGI scripts spawned; it also allows scripts to be run to handle the -authentication, authorization and access check phases. +authentication, authorization, and access check phases. -For more information see the FastCGI documentation, the C module and -L. +For more information see the FastCGI documentation, the C module +and L. +=head2 Serving static content -B +Serving static content in Catalyst can be somewhat tricky; this recipe +shows one possible solution. Using this recipe will serve all static +content through Catalyst when developing with the built-in HTTP::Daemon +server, and will make it easy to use Apache to serve the content when +your app goes into production. -PersistentPerl (previously known as C) is a persistent Perl -interpreter. After the script is initially run, instead of exiting, the perl -interpreter is kept running. During subsequent runs, this interpreter is used -to handle new executions instead of starting a new perl interpreter each -time. A very fast frontend program contacts the persistent Perl process, which -is usually already running, to do the work and return the results. -PersistentPerl can be used to speed up perl CGI scripts. It also provides an -Apache module so that scripts can be run without the overhead of doing a -fork/exec for each request. +Static content is best served from a single directory within your root +directory. Having many different directories such as C and +C requires more code to manage, because you must separately +identify each static directory--if you decide to add a C +directory, you'll need to change your code to account for it. In +contrast, keeping all static directories as subdirectories of a main +C directory makes things much easier to manager. Here's an +example of a typical root directory structure: -The code for PersistentPerl is simpler than for FastCGI; rather than waiting -in an accept loop the script runs to completion, however variables are not -reinitialized on subsequent runs but maintain their values from the previous -run. + root/ + root/content.tt + root/controller/stuff.tt + root/header.tt + root/static/ + root/static/css/main.css + root/static/images/logo.jpg + root/static/js/code.js - #!/usr/bin/perperl - use strict; - use vars qw($output $initialized); - use PersistentPerl; - use MyApp; +All static content lives under C with everything else being +Template Toolkit files. Now you can identify the static content by +matching C from within Catalyst. - if (!$initialized++) { - # initialization code - set up database, etc - if ($PersistentPerl::i_am_per_perl) { - # PP-specific initialization code - } +=head3 Serving with HTTP::Daemon (myapp_server.pl) + +To serve these files under the standalone server, we first must load the +Static plugin. Install L if it's not already +installed. + +In your main application class (MyApp.pm), load the plugin: + + use Catalyst qw/-Debug FormValidator Static OtherPlugin/; + +You will also need to make sure your end method does I forward +static content to the view, perhaps like this: + + sub end : Private { + my ( $self, $c ) = @_; + + $c->forward( 'MyApp::V::TT' ) + unless ( $c->res->body || !$c->stash->{template} ); } - { - local(*STDOUT); - open( STDOUT, '>', \$output ); - MyApp->run; + +This code will only forward to the view if a template has been +previously defined by a controller and if there is not already data in +C<$c-Eres-Ebody>. + +Next, create a controller to handle requests for the /static path. Use +the Helper to save time. This command will create a stub controller as +C. + + $ script/myapp_create.pl controller Static + +Edit the file and add the following methods: + + # serve all files under /static as static files + sub default : Path('/static') { + my ( $self, $c ) = @_; + + # Optional, allow the browser to cache the content + $c->res->headers->header( 'Cache-Control' => 'max-age=86400' ); + + $c->serve_static; # from Catalyst::Plugin::Static + } + + # also handle requests for /favicon.ico + sub favicon : Path('/favicon.ico') { + my ( $self, $c ) = @_; + + $c->serve_static; } - $output =~ s!^HTTP/\d+.\d+ \d\d\d.*?\n!!s; - print $output; -For more information see the C documentation. +You can also define a different icon for the browser to use instead of +favicon.ico by using this in your HTML header: + + + +=head3 Common problems + +The Static plugin makes use of the C package to +automatically determine MIME types. This package is notoriously +difficult to install, especially on win32 and OSX. For OSX the easiest +path might be to install Fink, then use C. Restart the server, and everything should be fine. + +Make sure you are using the latest version (>= 0.16) for best +results. If you are having errors serving CSS files, or if they get +served as text/plain instead of text/css, you may have an outdated +shared-mime-info version. You may also wish to simply use the following +code in your Static controller: + + if ($c->req->path =~ /css$/i) { + $c->serve_static( "text/css" ); + } else { + $c->serve_static; + } + +=head3 Serving with Apache + +When using Apache, you can completely bypass Catalyst and the Static +controller by intercepting requests for the C path at the +server level. All that is required is to define a DocumentRoot and add a +separate Location block for your static content. Here is a complete +config for this application under mod_perl 1.x; variations, some of +which could be simpler, are left as an exercise for the reader: + + + use lib qw(/var/www/MyApp/lib); + + PerlModule MyApp + + + ServerName myapp.example.com + DocumentRoot /var/www/MyApp/root + + SetHandler perl-script + PerlHandler MyApp + + + SetHandler default-handler + + + +=head2 Forwarding with arguments + +Sometimes you want to pass along arguments when forwarding to another +action. This can be accomplished by simply setting the arguments before +the forward: + + $c->req->args([qw/arg1 arg2 arg3/]); + $c->forward('/wherever'); =head1 AUTHOR Sebastian Riedel, C -Danijel Milicevic C -Viljo Marrandi C +Danijel Milicevic, C +Viljo Marrandi, C +Marcus Ramberg, C +Andy Grundman, C =head1 COPYRIGHT -This program is free software, you can redistribute it and/or modify it under -the same terms as Perl itself. +This program is free software, you can redistribute it and/or modify it +under the same terms as Perl itself.