X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCatalyst%2FManual%2FCookbook.pod;h=5d56a469589c69ed0655ab69dbbbf2737d0ef3bd;hb=02a53b81a62d7559d61f5dffbc57be0713c05129;hp=68d66d8724d7101034d0a64d6b38c76daaccf87b;hpb=61b1e958102e2371a79e07a7e2cdbb371797d202;p=catagits%2FCatalyst-Runtime.git diff --git a/lib/Catalyst/Manual/Cookbook.pod b/lib/Catalyst/Manual/Cookbook.pod index 68d66d8..5d56a46 100644 --- a/lib/Catalyst/Manual/Cookbook.pod +++ b/lib/Catalyst/Manual/Cookbook.pod @@ -11,7 +11,7 @@ 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. +placing a C call in the C action. sub end : Private { my ( $self, $c ) = @_; @@ -19,9 +19,9 @@ placing a die() call in the _end action. } If you're tired of removing and adding this all the time, you -can easily add a condition. for example: +can easily add a condition. For example: - die "Testing" if $c->param->{dump_info}; + die "Testing" if $c->params->{dump_info}; =head2 Disable statistics @@ -33,7 +33,7 @@ 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; @@ -69,7 +69,7 @@ Just use Catalyst::Model::CDBI::CRUD as baseclass. Modify the $c->form() parameters to match your needs, and don't forget to copy the templates. ;) -=head2 Uploads with Catalyst +=head2 Single file upload with Catalyst To implement uploads in Catalyst you need to have a HTML form similiar to this: @@ -80,38 +80,81 @@ this: -It's very important not to forget enctype="multipart/form-data" in form, -if it's not there, uploads just don't work. +It's very important not to forget C in form. Uploads will not work without this. Catalyst Controller module 'upload' action: - sub upload : Global { - my ($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': $!" ); + } + } + } + + $c->stash->{template} = 'file_upload.html'; + } + +=head2 Multiple file upload with Catalyst + +Code for uploading multiple files from one form needs little changes compared +to single file upload. + +Form goes like this: + +
+ +
+
+
+ +
+ +Controller: + + sub upload : Local { + my ($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} = 'upload_form.tt'; - $c->forward('MyApp::V::View'); } -If you want to upload bigger files than 1MB, then just add to your Controller -module: + $c->stash->{template} = 'file_upload.html'; + } + +Creq->upload)> loops automatically over all file input +fields and gets input names. After that is basic file saving code, just like in +single file upload. + +Notice: Cing might not be what you want to do, when an error occurs, but +it works as an example. A better idea would be to store error C<$!> in +$c->stash->{error} and show a custom error template displaying this message. - $CGI::Simple::POST_MAX = 1048576000; +For more information about uploads and usable methods look at +C and C. =head2 Authentication with Catalyst::Plugin::Authentication::CDBI There are (at least) two ways to implement authentication with this plugin: -1) only checking username and password +1) only checking username and password; 2) checking username, password and the roles the user has For both variants you'll need the following code in your MyApp package: @@ -124,26 +167,26 @@ For both variants you'll need the following code in your MyApp package: 'user_class' is a Class::DBI class for your users table. 'user_field' tells which field is used for username lookup (might be -email, first name, surname etc). +email, first name, surname etc.). 'password_field' is, well, password field in your table and by default password is stored in plain text. Authentication::CDBI looks for 'user' and 'password' fields in table, if they're not defined in the config. -In PostgreSQL users table might be something like: +In PostgreSQL, the users table might be something like: -CREATE TABLE users ( - user_id serial, - name varchar(100), - surname varchar(100), - password varchar(100), - email varchar(100), - primary key(user_id) -); + CREATE TABLE users ( + user_id serial, + name varchar(100), + surname varchar(100), + password varchar(100), + email varchar(100), + primary key(user_id) + ); We'll discuss the first variant for now: -1. user:password login / auth without roles +1. user:password login/auth without roles -To log in a user you might use a action like this: +To log in a user you might use an action like this: sub 'login' : Local { my ($self, $c) = @_; @@ -160,19 +203,18 @@ $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. -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 $c->req->{user} +If you want to remember the user's login status in between further +requests, then just use the C<$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 $c->session_logout. -Now lets take a look at the second variant: -2. user:password login / auth with roles +Now let's take a look at the second variant: +2. user:password login/auth with roles -To use roles you need to add to MyApp->config in the 'authentication' -section following parameters: +To use roles you need to add the following parameters to MyApp->config in the 'authentication' section: role_class => 'MyApp::M::MyApp::Roles', user_role_class => 'MyApp::M::MyApp::UserRoles', @@ -181,26 +223,26 @@ section following parameters: Corresponding tables in PostgreSQL could look like this: -CREATE TABLE roles ( - role_id serial, - name varchar(100), - primary key(role_id) -); - -CREATE TABLE user_roles ( - user_role_id serial, - user_id int, - role_id int, - primary key(user_role_id), - foreign key(user_id) references users(user_id), - foreign key(role_id) references roles(role_id) -); + CREATE TABLE roles ( + role_id serial, + name varchar(100), + primary key(role_id) + ); + + CREATE TABLE user_roles ( + user_role_id serial, + user_id int, + role_id int, + primary key(user_role_id), + foreign key(user_id) references users(user_id), + foreign key(role_id) references roles(role_id) + ); The 'roles' table is a list of role names and the 'user_role' table is used for the user -> role lookup. -Now if a logged in user wants to see a location which is allowed only -for people with 'admin' role then in you controller you can check it +Now if a logged-in user wants to see a location which is allowed only +for people with an 'admin' role, in your controller you can check it with: sub add : Local { @@ -208,14 +250,14 @@ with: if ($c->roles(qw/admin/)) { $c->req->output("Your account has the role 'admin.'"); } else { - $c->req->output("You're not allowed to be here"); + $c->req->output("You're not allowed to be here."); } } -One thing you might need is to forward non-authenticated users to login -form, if they try to access restricted areas. If you want to do this -controller-wide (if you have one controller for admin section) then it's -best to add user check to '!begin' action: +One thing you might need is to forward non-authenticated users to a login +form if they try to access restricted areas. If you want to do this +controller-wide (if you have one controller for your admin section) then it's +best to add a user check to a '!begin' action: sub begin : Private { my ($self, $c) = @_; @@ -225,23 +267,23 @@ best to add user check to '!begin' action: } } -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 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. +just too slow. There's also an alternative to mod_perl that gives +reasonable performance named FastCGI. B @@ -267,7 +309,7 @@ it is done - and it also works as a normal, single-shot CGI script. Any initialization code should be included outside the request-accept loop. -There is one little complication, which is that Crun> outputs a +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 @@ -293,49 +335,11 @@ 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. - -B - -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. - -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. - - - #!/usr/bin/perperl - use strict; - use vars qw($output $initialized); - use PersistentPerl; - use MyApp; - - if (!$initialized++) { - # initialization code - set up database, etc - if ($PersistentPerl::i_am_per_perl) { - # PP-specific initialization code - } - } - - MyApp->run; - -For more information see the C documentation. - - =head1 AUTHOR Sebastian Riedel, C