Update Changes to reflect recent updates
[catagits/Catalyst-Manual.git] / lib / Catalyst / Manual / Tutorial / Authentication.pod
d442cc9f 1=head1 NAME
3533daff 3Catalyst::Manual::Tutorial::Authentication - Catalyst Tutorial - Part 5: Authentication
d442cc9f 4
6=head1 OVERVIEW
3533daff 8This is B<Part 5 of 10> for the Catalyst tutorial.
d442cc9f 9
10L<Tutorial Overview|Catalyst::Manual::Tutorial>
12=over 4
14=item 1
18=item 2
20L<Catalyst Basics|Catalyst::Manual::Tutorial::CatalystBasics>
22=item 3
3533daff 24L<More Catalyst Basics|Catalyst::Manual::Tutorial::MoreCatalystBasics>
d442cc9f 25
26=item 4
3533daff 28L<Basic CRUD|Catalyst::Manual::Tutorial::BasicCRUD>
d442cc9f 29
30=item 5
3533daff 32B<Authentication>
d442cc9f 33
34=item 6
3533daff 36L<Authorization|Catalyst::Manual::Tutorial::Authorization>
d442cc9f 37
38=item 7
3533daff 40L<Debugging|Catalyst::Manual::Tutorial::Debugging>
d442cc9f 41
42=item 8
3533daff 44L<Testing|Catalyst::Manual::Tutorial::Testing>
d442cc9f 45
46=item 9
3533daff 48L<Advanced CRUD|Catalyst::Manual::Tutorial::AdvancedCRUD>
d442cc9f 49
3533daff 50=item 10
d442cc9f 51
3533daff 52L<Appendices|Catalyst::Manual::Tutorial::Appendices>
d442cc9f 53
3533daff 54=back
2d0526d1 55
2d0526d1 56
d442cc9f 57=head1 DESCRIPTION
905a3a26 59Now that we finally have a simple yet functional application, we can
60focus on providing authentication (with authorization coming next in
9ad715b3 61Part 6).
d442cc9f 62
63This part of the tutorial is divided into two main sections: 1) basic,
64cleartext authentication and 2) hash-based authentication.
66You can checkout the source code for this example from the catalyst
67subversion repository as per the instructions in
1390ef0e 68L<Catalyst::Manual::Tutorial::Intro|Catalyst::Manual::Tutorial::Intro>.
d442cc9f 69
72This section explores how to add authentication logic to a Catalyst
76=head2 Add Users and Roles to the Database
78First, we add both user and role information to the database (we will
79add the role information here although it will not be used until the
9ad715b3 80authorization section, Part 6). Create a new SQL script file by opening
d442cc9f 81C<myapp02.sql> in your editor and insert:
83 --
84 -- Add users and roles tables, along with a many-to-many join table
85 --
86 CREATE TABLE users (
88 username TEXT,
89 password TEXT,
90 email_address TEXT,
91 first_name TEXT,
92 last_name TEXT,
93 active INTEGER
94 );
95 CREATE TABLE roles (
97 role TEXT
98 );
99 CREATE TABLE user_roles (
100 user_id INTEGER,
101 role_id INTEGER,
102 PRIMARY KEY (user_id, role_id)
103 );
104 --
105 -- Load up some initial test data
106 --
107 INSERT INTO users VALUES (1, 'test01', 'mypass', 't01@na.com', 'Joe', 'Blow', 1);
108 INSERT INTO users VALUES (2, 'test02', 'mypass', 't02@na.com', 'Jane', 'Doe', 1);
109 INSERT INTO users VALUES (3, 'test03', 'mypass', 't03@na.com', 'No', 'Go', 0);
110 INSERT INTO roles VALUES (1, 'user');
111 INSERT INTO roles VALUES (2, 'admin');
112 INSERT INTO user_roles VALUES (1, 1);
113 INSERT INTO user_roles VALUES (1, 2);
114 INSERT INTO user_roles VALUES (2, 1);
115 INSERT INTO user_roles VALUES (3, 1);
117Then load this into the C<myapp.db> database with the following command:
119 $ sqlite3 myapp.db < myapp02.sql
122=head2 Add User and Role Information to DBIC Schema
3533daff 124Although we could manually edit the DBIC schema information to include
125the new tables added in the previous step, let's use the C<create=static>
126option on the DBIC model helper to do most of the work for us:
d442cc9f 127
d0496197 128 $ script/myapp_create.pl model DB DBIC::Schema MyApp::Schema create=static dbi:SQLite:myapp.db
1390ef0e 129 exists "/root/dev/MyApp/script/../lib/MyApp/Model"
130 exists "/root/dev/MyApp/script/../t"
131 Dumping manual schema for MyApp::Schema to directory /root/dev/MyApp/script/../lib ...
132 Schema dump completed.
133 exists "/root/dev/MyApp/script/../lib/MyApp/Model/DB.pm"
134 $
d0496197 135 $ ls lib/MyApp/Schema
3533daff 136 Authors.pm BookAuthors.pm Books.pm Roles.pm UserRoles.pm Users.pm
d442cc9f 137
905a3a26 138Notice how the helper has added three new table-specific result source
139files to the C<lib/MyApp/Schema/MyApp> directory. And, more
140importantly, even if there were changes to the existing result source
141files, those changes would have only been written above the C<# DO NOT
191dee29 142MODIFY THIS OR ANYTHING ABOVE!> comment and your hand-edited
3533daff 143enhancements would have been preserved.
d442cc9f 144
191dee29 145Speaking of "hand-edit ted enhancements," we should now add
905a3a26 146relationship information to the three new result source files. Edit
147each of these files and add the following information between the C<#
3533daff 148DO NOT MODIFY THIS OR ANYTHING ABOVE!> comment and the closing C<1;>:
d442cc9f 149
d0496197 150C<lib/MyApp/Schema/Users.pm>:
d442cc9f 151
d442cc9f 152 #
153 # Set relationships:
154 #
1390ef0e 155
d442cc9f 156 # has_many():
157 # args:
158 # 1) Name of relationship, DBIC will create accessor with this name
159 # 2) Name of the model class referenced by this relationship
160 # 3) Column name in *foreign* table
d0496197 161 __PACKAGE__->has_many(map_user_role => 'MyApp::Schema::UserRoles', 'user_id');
1390ef0e 162
3533daff 163 # many_to_many():
164 # args:
165 # 1) Name of relationship, DBIC will create accessor with this name
905a3a26 166 # 2) Name of has_many() relationship this many_to_many() is shortcut for
167 # 3) Name of belongs_to() relationship in model class of has_many() above
3533daff 168 # You must already have the has_many() defined to use a many_to_many().
169 __PACKAGE__->many_to_many(roles => 'map_user_role', 'role');
d442cc9f 170
d0496197 172C<lib/MyApp/Schema/Roles.pm>:
d442cc9f 173
d442cc9f 174 #
175 # Set relationships:
176 #
1390ef0e 177
d442cc9f 178 # has_many():
179 # args:
180 # 1) Name of relationship, DBIC will create accessor with this name
181 # 2) Name of the model class referenced by this relationship
182 # 3) Column name in *foreign* table
d0496197 183 __PACKAGE__->has_many(map_user_role => 'MyApp::Schema::UserRoles', 'role_id');
d442cc9f 184
d0496197 186C<lib/MyApp/Schema/UserRoles.pm>:
d442cc9f 187
d442cc9f 188 #
189 # Set relationships:
190 #
1390ef0e 191
d442cc9f 192 # belongs_to():
193 # args:
194 # 1) Name of relationship, DBIC will create accessor with this name
195 # 2) Name of the model class referenced by this relationship
196 # 3) Column name in *this* table
d0496197 197 __PACKAGE__->belongs_to(user => 'MyApp::Schema::Users', 'user_id');
1390ef0e 198
d442cc9f 199 # belongs_to():
200 # args:
201 # 1) Name of relationship, DBIC will create accessor with this name
202 # 2) Name of the model class referenced by this relationship
203 # 3) Column name in *this* table
d0496197 204 __PACKAGE__->belongs_to(role => 'MyApp::Schema::Roles', 'role_id');
d442cc9f 205
3533daff 206
905a3a26 207The code for these three sets of updates is obviously very similar to
208the edits we made to the C<Books>, C<Authors>, and C<BookAuthors>
3533daff 209classes created in Part 3.
905a3a26 211Note that we do not need to make any change to the
212C<lib/MyApp/Schema.pm> schema file. It simply tells DBIC to
79a529cc 213load all of the result class files it finds in below the
905a3a26 214C<lib/MyApp/Schema> directory, so it will automatically pick
3533daff 215up our new table information.
d442cc9f 216
218=head2 Sanity-Check Reload of Development Server
905a3a26 220We aren't ready to try out the authentication just yet; we only want
221to do a quick check to be sure our model loads correctly. Press
222C<Ctrl-C> to kill the previous server instance (if it's still running)
3533daff 223and restart it:
d442cc9f 224
225 $ script/myapp_server.pl
227Look for the three new model objects in the startup debug output:
229 ...
230 .-------------------------------------------------------------------+----------.
231 | Class | Type |
232 +-------------------------------------------------------------------+----------+
233 | MyApp::Controller::Books | instance |
234 | MyApp::Controller::Root | instance |
d0496197 235 | MyApp::Model::DB | instance |
236 | MyApp::Model::DB::Author | class |
237 | MyApp::Model::DB::Books | class |
238 | MyApp::Model::DB::BookAuthors | class |
239 | MyApp::Model::DB::Roles | class |
240 | MyApp::Model::DB::Users | class |
241 | MyApp::Model::DB::UserRoles | class |
d442cc9f 242 | MyApp::View::TT | instance |
243 '-------------------------------------------------------------------+----------'
244 ...
79a529cc 246Again, notice that your "result class" classes have been "re-loaded"
3533daff 247by Catalyst under C<MyApp::Model>.
d442cc9f 248
250=head2 Include Authentication and Session Plugins
905a3a26 252Edit C<lib/MyApp.pm> and update it as follows (everything below
3533daff 253C<StackTrace> is new):
d442cc9f 254
1390ef0e 255 __PACKAGE__->setup(qw/
d442cc9f 256 -Debug
257 ConfigLoader
258 Static::Simple
1390ef0e 259
d442cc9f 260 StackTrace
1390ef0e 261
d442cc9f 262 Authentication
1390ef0e 263
d442cc9f 264 Session
265 Session::Store::FastMmap
266 Session::State::Cookie
1390ef0e 267 /);
d442cc9f 268
94d8da41 269B<Note:> As discussed in MoreCatalystBasics, different versions of
270C<Catalyst::Devel> have used a variety of methods to load the plugins.
533fee73 271You can put the plugins in the C<use Catalyst> statement if you prefer.
94d8da41 272
905a3a26 273The C<Authentication> plugin supports Authentication while the
274C<Session> plugins are required to maintain state across multiple HTTP
6d0971ad 276
905a3a26 277Note that the only required Authentication class is the main one. This
278is a change that occurred in version 0.09999_01 of the
279C<Authentication> plugin. You B<do not need> to specify a particular
280Authentication::Store or Authentication::Credential plugin. Instead,
281indicate the Store and Credential you want to use in your application
6d0971ad 282configuration (see below).
905a3a26 284Note that there are several options for
287is generally a good choice if you are on Unix; try
288L<Session::Store::File|Catalyst::Plugin::Session::Store::File> if you
289are on Win32) -- consult
290L<Session::Store|Catalyst::Plugin::Session::Store> and its subclasses
3533daff 291for additional information and options (for example to use a database-
292backed session store).
d442cc9f 293
295=head2 Configure Authentication
905a3a26 297Although C<__PACKAGE__-E<gt>config(name =E<gt> 'value');> is still
298supported, newer Catalyst applications tend to place all configuration
299information in C<myapp.conf> and automatically load this information
300into C<MyApp-E<gt>config> using the
301L<ConfigLoader|Catalyst::Plugin::ConfigLoader> plugin.
15e1d0b2 302
905a3a26 303First, as noted in Part 3 of the tutorial, Catalyst has recently
304switched from a default config file format of YAML to
79a529cc 305C<Config::General> (an apache-like format). In case you are using a
306version of Catalyst earlier than v5.7014, delete the C<myapp.yml>, or
307convert it to .conf format using the TIP in
308L<Catalyst::Manual::MoreCatalystBasics>; then simply follow the
309directions below to create a new C<myapp.conf> file.
15e1d0b2 310
905a3a26 311Here, we need to load several parameters that tell
313where to locate information in your database. To do this, edit the
c010ae0d 314C<myapp.conf> file and update it to match:
1390ef0e 316 # rename this file to MyApp.yml and put a : in front of "name" if
317 # you want to use yaml like in old versions of Catalyst
c010ae0d 318 name MyApp
319 <authentication>
320 default_realm dbic
321 <realms>
322 <dbic>
323 <credential>
905a3a26 324 # Note: this first definition would be the same as setting
3533daff 325 # __PACKAGE__->config->{authentication}->{realms}->{dbic}
905a3a26 326 # ->{credential} = 'Password' in lib/MyApp.pm
3533daff 327 #
328 # Specify that we are going to do password-based auth
c010ae0d 329 class Password
3533daff 330 # This is the name of the field in the users table with the
331 # password stored in it
c010ae0d 332 password_field password
905a3a26 333 # We are using an unencrypted password for now
c010ae0d 334 password_type clear
335 </credential>
336 <store>
3533daff 337 # Use DBIC to retrieve username, password & role information
c010ae0d 338 class DBIx::Class
905a3a26 339 # This is the model object created by Catalyst::Model::DBIC
d0496197 340 # from your schema (you created 'MyApp::Schema::User' but as
905a3a26 341 # the Catalyst startup debug messages show, it was loaded as
d0496197 342 # 'MyApp::Model::DB::Users').
905a3a26 343 # NOTE: Omit 'MyApp::Model' here just as you would when using
d0496197 344 # '$c->model("DB::Users)'
345 user_class DB::Users
c010ae0d 346 </store>
347 </dbic>
d0496197 348 </realms>
349 </authentication>
d442cc9f 350
351Inline comments in the code above explain how each field is being used.
c010ae0d 353Note that you can use many other config file formats with catalyst.
354See L<Catalyst::Plugin::ConfigLoader|Catalyst::Plugin::ConfigLoader>
355for details.
d442cc9f 356
1390ef0e 357
d442cc9f 358=head2 Add Login and Logout Controllers
360Use the Catalyst create script to create two stub controller files:
362 $ script/myapp_create.pl controller Login
363 $ script/myapp_create.pl controller Logout
d0496197 365B<NOTE:> You could easily use a single controller here. For example,
d442cc9f 366you could have a C<User> controller with both C<login> and C<logout>
367actions. Remember, Catalyst is designed to be very flexible, and leaves
368such matters up to you, the designer and programmer.
905a3a26 370Then open C<lib/MyApp/Controller/Login.pm>, locate the C<sub index
371:Path :Args(0)> method (or C<sub index : Private> if you are using an
372older version of Catalyst) that was automatically inserted by the
94d8da41 373helpers when we created the Login controller above, and update the
374definition of C<sub index> to match:
d442cc9f 375
376 =head2 index
1390ef0e 377
d442cc9f 378 Login logic
1390ef0e 379
d442cc9f 380 =cut
1390ef0e 381
ae492862 382 sub index :Path :Args(0) {
d442cc9f 383 my ($self, $c) = @_;
1390ef0e 384
d442cc9f 385 # Get the username and password from form
386 my $username = $c->request->params->{username} || "";
387 my $password = $c->request->params->{password} || "";
1390ef0e 388
d442cc9f 389 # If the username and password values were found in form
390 if ($username && $password) {
391 # Attempt to log the user in
905a3a26 392 if ($c->authenticate({ username => $username,
5fefca35 393 password => $password } )) {
d442cc9f 394 # If successful, then let them use the application
395 $c->response->redirect($c->uri_for('/books/list'));
396 return;
397 } else {
398 # Set an error message
399 $c->stash->{error_msg} = "Bad username or password.";
400 }
401 }
1390ef0e 402
d442cc9f 403 # If either of above don't work out, send to the login page
404 $c->stash->{template} = 'login.tt2';
405 }
407This controller fetches the C<username> and C<password> values from the
905a3a26 408login form and attempts to authenticate the user. If successful, it
409redirects the user to the book list page. If the login fails, the user
410will stay at the login page and receive an error message. If the
411C<username> and C<password> values are not present in the form, the
f632e28b 412user will be taken to the empty login form.
d442cc9f 413
1390ef0e 414Note that we could have used something like C<sub default :Path>,
415however, it is generally recommended (partly for historical reasons,
416and partly for code clarity) only to use C<default> in
417C<MyApp::Controller::Root>, and then mainly to generate the 404 not
85d49fb6 418found page for the application.
ae492862 419
e075db0c 420Instead, we are using C<sub somename :Path :Args(0) {...}> here to
905a3a26 421specifically match the URL C</login>. C<Path> actions (aka, "literal
422actions") create URI matches relative to the namespace of the
423controller where they are defined. Although C<Path> supports
424arguments that allow relative and absolute paths to be defined, here
425we use an empty C<Path> definition to match on just the name of the
426controller itself. The method name, C<index>, is arbitrary. We make
ae492862 427the match even more specific with the C<:Args(0)> action modifier --
905a3a26 428this forces the match on I<only> C</login>, not
d442cc9f 429C</login/somethingelse>.
905a3a26 431Next, update the corresponding method in
3533daff 432C<lib/MyApp/Controller/Logout.pm> to match:
d442cc9f 433
434 =head2 index
1390ef0e 435
d442cc9f 436 Logout logic
1390ef0e 437
d442cc9f 438 =cut
1390ef0e 439
ae492862 440 sub index :Path :Args(0) {
d442cc9f 441 my ($self, $c) = @_;
1390ef0e 442
d442cc9f 443 # Clear the user's state
444 $c->logout;
1390ef0e 445
d442cc9f 446 # Send the user to the starting point
447 $c->response->redirect($c->uri_for('/'));
448 }
905a3a26 450As with the login controller, be sure to delete the
14e5ed66 451C<$c-E<gt>response-E<gt>body('Matched MyApp::Controller::Logout in Logout.');>
d442cc9f 452line of the C<sub index>.
455=head2 Add a Login Form TT Template Page
457Create a login form by opening C<root/src/login.tt2> and inserting:
459 [% META title = 'Login' %]
1390ef0e 460
d442cc9f 461 <!-- Login form -->
8a7c5151 462 <form method="post" action="[% c.uri_for('/login') %]">
d442cc9f 463 <table>
464 <tr>
465 <td>Username:</td>
466 <td><input type="text" name="username" size="40" /></td>
467 </tr>
468 <tr>
469 <td>Password:</td>
470 <td><input type="password" name="password" size="40" /></td>
471 </tr>
472 <tr>
473 <td colspan="2"><input type="submit" name="submit" value="Submit" /></td>
474 </tr>
475 </table>
476 </form>
479=head2 Add Valid User Check
481We need something that provides enforcement for the authentication
482mechanism -- a I<global> mechanism that prevents users who have not
483passed authentication from reaching any pages except the login page.
484This is generally done via an C<auto> action/method (prior to Catalyst
485v5.66, this sort of thing would go in C<MyApp.pm>, but starting in
486v5.66, the preferred location is C<lib/MyApp/Controller/Root.pm>).
488Edit the existing C<lib/MyApp/Controller/Root.pm> class file and insert
489the following method:
491 =head2 auto
1390ef0e 492
d442cc9f 493 Check if there is a user and, if not, forward to login page
1390ef0e 494
d442cc9f 495 =cut
1390ef0e 496
d442cc9f 497 # Note that 'auto' runs after 'begin' but before your actions and that
905a3a26 498 # 'auto's "chain" (all from application path to most specific class are run)
d442cc9f 499 # See the 'Actions' section of 'Catalyst::Manual::Intro' for more info.
500 sub auto : Private {
501 my ($self, $c) = @_;
1390ef0e 502
d442cc9f 503 # Allow unauthenticated users to reach the login page. This
191dee29 504 # allows unauthenticated users to reach any action in the Login
d442cc9f 505 # controller. To lock it down to a single action, we could use:
506 # if ($c->action eq $c->controller('Login')->action_for('index'))
905a3a26 507 # to only allow unauthenticated access to the 'index' action we
d442cc9f 508 # added above.
509 if ($c->controller eq $c->controller('Login')) {
510 return 1;
511 }
1390ef0e 512
d442cc9f 513 # If a user doesn't exist, force login
514 if (!$c->user_exists) {
515 # Dump a log message to the development server debug output
516 $c->log->debug('***Root::auto User not found, forwarding to /login');
517 # Redirect the user to the login page
518 $c->response->redirect($c->uri_for('/login'));
519 # Return 0 to cancel 'post-auto' processing and prevent use of application
520 return 0;
521 }
1390ef0e 522
d442cc9f 523 # User found, so return 1 to continue with processing after this 'auto'
524 return 1;
525 }
3533daff 527
e075db0c 528B<Note:> Catalyst provides a number of different types of actions,
529such as C<Chained>, C<Local>, C<Regex>, C<Private> and C<Path>. You
530should refer to L<Catalyst::Manual::Intro/Action_types> for a more
531detailed explanation, but the following bullet points provide a quick
d442cc9f 533
534=over 4
536=item *
e075db0c 538In the past, the majority of applications have traditionally used
539C<Local> actions for items that respond to user requests and
540C<Private> actions for those that do not directly respond to user
d442cc9f 542
543=item *
e075db0c 545As discussed in Part 4 of the tutorial, newer Catalyst applications
546tend to use the Chained dispatch form of action types because of its
547power and flexibility. See
551for more information on chained actions.
3533daff 552
553=item *
e075db0c 555C<Path> actions provide a limited subset of what can be found done
556with Chained actions. You can match on different portions of the URI
557(for example C<Path('list')> in C<lib/MyApp/Controller/Books.pm> would
558match on the URL C<http://localhost:3000/books/list> but
559C<Path('/list')> would match on C<http://localhost:3000/list>). You
560can also specify the number of arguments to match via C<Args> much
561like the endpoint of a chain. However, becaused Chained actions offer
562these features and so much more (at the expense of some additional
563complexity), Chained action types are generally recommened.
3533daff 564
565=item *
567There are five types of build-in C<Private> actions: C<begin>, C<end>,
d442cc9f 568C<default>, C<index>, and C<auto>.
570=item *
572With C<begin>, C<end>, C<default>, C<index> private actions, only the
573most specific action of each type will be called. For example, if you
905a3a26 574define a C<begin> action in your controller it will I<override> a
d442cc9f 575C<begin> action in your application/root controller -- I<only> the
576action in your controller will be called.
578=item *
905a3a26 580Unlike the other actions where only a single method is called for each
581request, I<every> auto action along the chain of namespaces will be
d442cc9f 582called. Each C<auto> action will be called I<from the application/root
583controller down through the most specific class>.
587By placing the authentication enforcement code inside the C<auto> method
588of C<lib/MyApp/Controller/Root.pm> (or C<lib/MyApp.pm>), it will be
589called for I<every> request that is received by the entire application.
592=head2 Displaying Content Only to Authenticated Users
594Let's say you want to provide some information on the login page that
595changes depending on whether the user has authenticated yet. To do
596this, open C<root/src/login.tt2> in your editor and add the following
597lines to the bottom of the file:
599 <p>
600 [%
905a3a26 601 # This code illustrates how certain parts of the TT
d442cc9f 602 # template will only be shown to users who have logged in
603 %]
8a7c5151 604 [% IF c.user_exists %]
605 Please Note: You are already logged in as '[% c.user.username %]'.
606 You can <a href="[% c.uri_for('/logout') %]">logout</a> here.
d442cc9f 607 [% ELSE %]
608 You need to log in to use this application.
609 [% END %]
610 [%#
611 Note that this whole block is a comment because the "#" appears
905a3a26 612 immediate after the "[%" (with no spaces in between). Although it
613 can be a handy way to temporarily "comment out" a whole block of
614 TT code, it's probably a little too subtle for use in "normal"
d442cc9f 615 comments.
616 %]
3533daff 617 </p>
d442cc9f 618
619Although most of the code is comments, the middle few lines provide a
620"you are already logged in" reminder if the user returns to the login
621page after they have already authenticated. For users who have not yet
622authenticated, a "You need to log in..." message is displayed (note the
623use of an IF-THEN-ELSE construct in TT).
626=head2 Try Out Authentication
628Press C<Ctrl-C> to kill the previous server instance (if it's still
629running) and restart it:
631 $ script/myapp_server.pl
1390ef0e 633B<IMPORTANT NOTE:> If you are having issues with authentication on
634Internet Explorer, be sure to check the system clocks on both your
635server and client machines. Internet Explorer is very picky about
636timestamps for cookies. Note that you can quickly sync an Ubuntu
25ed8f40 637system with the following command:
639 sudo ntpdate ntp.ubuntu.com
d442cc9f 640
1390ef0e 641Or possibly try C<sudo ntpdate -u ntp.ubuntu.com> (to us an
642unpriviledged port) or C<sudo ntpdate pool.ntp.org> (to try a
643different server in case the Ubuntu NTP server is down).
645Now trying going to L<http://localhost:3000/books/list> and you should
646be redirected to the login page, hitting Shift+Reload or Ctrl+Reload
647if necessary (the "You are already logged in" message should I<not>
648appear -- if it does, click the C<logout> button and try again). Note
649the C<***Root::auto User not found...> debug message in the
650development server output. Enter username C<test01> and password
651C<mypass>, and you should be taken to the Book List page.
d442cc9f 652
653Open C<root/src/books/list.tt2> and add the following lines to the
3533daff 654bottom (below the closing </table> tag):
d442cc9f 655
656 <p>
8a7c5151 657 <a href="[% c.uri_for('/login') %]">Login</a>
658 <a href="[% c.uri_for('form_create') %]">Create</a>
d442cc9f 659 </p>
905a3a26 661Reload your browser and you should now see a "Login" and "Create" links
662at the bottom of the page (as mentioned earlier, you can update template
663files without reloading the development server). Click the first link
664to return to the login page. This time you I<should> see the "You are
d442cc9f 665already logged in" message.
667Finally, click the C<You can logout here> link on the C</login> page.
668You should stay at the login page, but the message should change to "You
669need to log in to use this application."
674In this section we increase the security of our system by converting
675from cleartext passwords to SHA-1 password hashes.
677B<Note:> This section is optional. You can skip it and the rest of the
678tutorial will function normally.
680Note that even with the techniques shown in this section, the browser
681still transmits the passwords in cleartext to your application. We are
682just avoiding the I<storage> of cleartext passwords in the database by
683using a SHA-1 hash. If you are concerned about cleartext passwords
684between the browser and your application, consider using SSL/TLS, made
685easy with the Catalyst plugin Catalyst::Plugin:RequireSSL.
688=head2 Get a SHA-1 Hash for the Password
690Catalyst uses the C<Digest> module to support a variety of hashing
691algorithms. Here we will use SHA-1 (SHA = Secure Hash Algorithm).
692First, we should compute the SHA-1 hash for the "mypass" password we are
693using. The following command-line Perl script provides a "quick and
694dirty" way to do this:
696 $ perl -MDigest::SHA -e 'print Digest::SHA::sha1_hex("mypass"), "\n"'
697 e727d1464ae12436e899a726da5b2f11d8381b26
698 $
905a3a26 700B<Note:> If you are following along in Ubuntu, you will need to install
d0496197 701C<Digest::SHA> with the following command to run the example code above:
905a3a26 703 sudo aptitude install libdigest-sha-perl
d0496197 704
d442cc9f 705B<Note:> You should probably modify this code for production use to
706not read the password from the command line. By having the script
707prompt for the cleartext password, it avoids having the password linger
708in forms such as your C<.bash_history> files (assuming you are using
709BASH as your shell). An example of such a script can be found in
710Appendix 3.
713=head2 Switch to SHA-1 Password Hashes in the Database
715Next, we need to change the C<password> column of our C<users> table to
716store this hash value vs. the existing cleartext password. Open
717C<myapp03.sql> in your editor and enter:
719 --
720 -- Convert passwords to SHA-1 hashes
721 --
722 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 1;
723 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 2;
724 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 3;
726Then use the following command to update the SQLite database:
728 $ sqlite3 myapp.db < myapp03.sql
1390ef0e 730B<Note:> We are using SHA-1 hashes here, but many other hashing
d442cc9f 731algorithms are supported. See C<Digest> for more information.
734=head2 Enable SHA-1 Hash Passwords in
45d511e0 737Edit C<myapp.conf> and update it to match (the C<password_type> and
d442cc9f 738C<password_hash_type> are new, everything else is the same):
1390ef0e 740 # rename this file to MyApp.yml and put a : in front of "name" if
741 # you want to use yaml like in old versions of Catalyst
c010ae0d 742 name MyApp
743 <authentication>
744 default_realm dbic
745 <realms>
746 <dbic>
747 <credential>
3533daff 748 # Note this first definition would be the same as setting
749 # __PACKAGE__->config->{authentication}->{realms}->{dbic}
905a3a26 750 # ->{credential} = 'Password' in lib/MyApp.pm
3533daff 751 #
752 # Specify that we are going to do password-based auth
c010ae0d 753 class Password
3533daff 754 # This is the name of the field in the users table with the
755 # password stored in it
c010ae0d 756 password_field password
3533daff 757 # Switch to more secure hashed passwords
c010ae0d 758 password_type hashed
3533daff 759 # Use the SHA-1 hashing algorithm
c010ae0d 760 password_hash_type SHA-1
d0496197 761 </credential>
c010ae0d 762 <store>
3533daff 763 # Use DBIC to retrieve username, password & role information
c010ae0d 764 class DBIx::Class
905a3a26 765 # This is the model object created by Catalyst::Model::DBIC
d0496197 766 # from your schema (you created 'MyApp::Schema::User' but as
905a3a26 767 # the Catalyst startup debug messages show, it was loaded as
d0496197 768 # 'MyApp::Model::DB::Users').
905a3a26 769 # NOTE: Omit 'MyApp::Model' here just as you would when using
d0496197 770 # '$c->model("DB::Users)'
771 user_class DB::Users
d0496197 772 </store>
773 </dbic>
774 </realms>
775 </authentication>
d442cc9f 776
1390ef0e 777
d442cc9f 778=head2 Try Out the Hashed Passwords
780Press C<Ctrl-C> to kill the previous server instance (if it's still
781running) and restart it:
783 $ script/myapp_server.pl
785You should now be able to go to L<http://localhost:3000/books/list> and
786login as before. When done, click the "Logout" link on the login page
787(or point your browser at L<http://localhost:3000/logout>).
d442cc9f 789
792As discussed in Part 3 of the tutorial, C<flash> allows you to set
905a3a26 793variables in a way that is very similar to C<stash>, but it will
d442cc9f 794remain set across multiple requests. Once the value is read, it
795is cleared (unless reset). Although C<flash> has nothing to do with
796authentication, it does leverage the same session plugins. Now that
797those plugins are enabled, let's go back and improve the "delete
798and redirect with query parameters" code seen at the end of the
905a3a26 799L<Basic CRUD|Catalyst::Manual::Tutorial::BasicCRUD> part of the
d442cc9f 800tutorial.
802First, open C<lib/MyApp/Controller/Books.pm> and modify C<sub delete>
3533daff 803to match the following (everything after the model search line of code
804has changed):
d442cc9f 805
905a3a26 806 =head2 delete
1390ef0e 807
d442cc9f 808 Delete a book
1390ef0e 809
d442cc9f 810 =cut
1390ef0e 811
d442cc9f 812 sub delete : Local {
813 # $id = primary key of book to delete
814 my ($self, $c, $id) = @_;
1390ef0e 815
d442cc9f 816 # Search for the book and then delete it
d0496197 817 $c->model('DB::Books')->search({id => $id})->delete_all;
1390ef0e 818
d442cc9f 819 # Use 'flash' to save information across requests until it's read
820 $c->flash->{status_msg} = "Book deleted";
1390ef0e 821
3533daff 822 # Redirect the user back to the list page
d442cc9f 823 $c->response->redirect($c->uri_for('/books/list'));
824 }
1390ef0e 826Next, open C<root/src/wrapper.tt2> and update the TT code to pull from
d442cc9f 827flash vs. the C<status_msg> query parameter:
1390ef0e 829 ...
d442cc9f 830 <div id="content">
1390ef0e 831 [%# Status and error messages %]
832 <span class="message">[% status_msg || c.flash.status_msg %]</span>
833 <span class="error">[% error_msg %]</span>
834 [%# This is where TT will stick all of your template's contents. -%]
835 [% content %]
836 </div><!-- end content -->
837 ...
905a3a26 838
1390ef0e 839Although the sample above only shows the C<content> div, leave the
840rest of the file intact -- the only change we made to the C<wrapper.tt2>
841was to add "C<|| c.request.params.status_msg>" to the
842C<E<lt>span class="message"E<gt>> line.
d442cc9f 843
845=head2 Try Out Flash
905a3a26 847Restart the development server and point your browser to
848L<http://localhost:3000/books/url_create/Test/1/4> to create an extra
849several books. Click the "Return to list" link and delete one of the
850"Test" books you just added. The C<flash> mechanism should retain our
3533daff 851"Book deleted" status message across the redirect.
d442cc9f 852
853B<NOTE:> While C<flash> will save information across multiple requests,
854I<it does get cleared the first time it is read>. In general, this is
855exactly what you want -- the C<flash> message will get displayed on
856the next screen where it's appropriate, but it won't "keep showing up"
857after that first time (unless you reset it). Please refer to
858L<Catalyst::Plugin::Session|Catalyst::Plugin::Session> for additional
1390ef0e 861
3533daff 862=head2 Switch To Flash-To-Stash
905a3a26 864Although the a use of flash above is certainly an improvement over the
1390ef0e 865C<status_msg> we employed in Part 4 of the tutorial, the
866C<status_msg || c.flash.status_msg> statement is a little ugly. A nice
905a3a26 867alternative is to use the C<flash_to_stash> feature that automatically
1390ef0e 868copies the content of flash to stash. This makes your controller
905a3a26 869and template code work regardless of where it was directly access, a
870forward, or a redirect. To enable C<flash_to_stash>, you can either
871set the value in C<lib/MyApp.pm> by changing the default
3533daff 872C<__PACKAGE__-E<gt>config> setting to something like:
874 __PACKAGE__->config(
875 name => 'MyApp',
876 session => {flash_to_stash => 1}
877 );
45d511e0 879B<or> add the following to C<myapp.conf>:
3533daff 880
45d511e0 881 <session>
882 flash_to_stash 1
883 </session>
3533daff 884
905a3a26 885The C<__PACKAGE__-E<gt>config> option is probably preferable here
886since it's not something you will want to change at runtime without it
3533daff 887possibly breaking some of your code.
1390ef0e 889Then edit C<root/src/wrapper.tt2> and change the C<status_msg> line
890to match the following:
3533daff 891
892 <span class="message">[% status_msg %]</span>
894Restart the development server and go to
905a3a26 895L<http://localhost:3000/books/list> in your browser. Delete another
3533daff 896of the "Test" books you added in the previous step. Flash should still
897maintain the status message across the redirect even though you are no
8a7c5151 898longer explicitly accessing C<c.flash>.
3533daff 899
d442cc9f 900
901=head1 AUTHOR
903Kennedy Clark, C<hkclark@gmail.com>
905Please report any errors, issues or suggestions to the author. The
906most recent version of the Catalyst Tutorial can be found at
82ab4bbf 907L<http://dev.catalyst.perl.org/repos/Catalyst/Catalyst-Manual/5.70/trunk/lib/Catalyst/Manual/Tutorial/>.
d442cc9f 908
45c7830f 909Copyright 2006-2008, Kennedy Clark, under Creative Commons License
95674086 910(L<http://creativecommons.org/licenses/by-sa/3.0/us/>).