Fix 2 typos - thanks to JGK
[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
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', '', 'Joe', 'Blow', 1);
108 INSERT INTO users VALUES (2, 'test02', 'mypass', '', 'Jane', 'Doe', 1);
109 INSERT INTO users VALUES (3, 'test03', 'mypass', '', '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/ model DB DBIC::Schema MyApp::Schema create=static dbi:SQLite:myapp.db
129 $ ls lib/MyApp/Schema
3533daff 130
d442cc9f 131
905a3a26 132Notice how the helper has added three new table-specific result source
133files to the C<lib/MyApp/Schema/MyApp> directory. And, more
134importantly, even if there were changes to the existing result source
135files, those changes would have only been written above the C<# DO NOT
136MODIFY THIS OR ANYTHING ABOVE!> comment and your hand-editted
3533daff 137enhancements would have been preserved.
d442cc9f 138
d442cc9f 139
905a3a26 140Speaking of "hand-editted enhancements," we should now add
141relationship information to the three new result source files. Edit
142each of these files and add the following information between the C<#
3533daff 143DO NOT MODIFY THIS OR ANYTHING ABOVE!> comment and the closing C<1;>:
d442cc9f 144
d0496197 145C<lib/MyApp/Schema/>:
d442cc9f 146
d442cc9f 147 #
148 # Set relationships:
149 #
905a3a26 150
d442cc9f 151 # has_many():
152 # args:
153 # 1) Name of relationship, DBIC will create accessor with this name
154 # 2) Name of the model class referenced by this relationship
155 # 3) Column name in *foreign* table
d0496197 156 __PACKAGE__->has_many(map_user_role => 'MyApp::Schema::UserRoles', 'user_id');
905a3a26 157
3533daff 158 # many_to_many():
159 # args:
160 # 1) Name of relationship, DBIC will create accessor with this name
905a3a26 161 # 2) Name of has_many() relationship this many_to_many() is shortcut for
162 # 3) Name of belongs_to() relationship in model class of has_many() above
3533daff 163 # You must already have the has_many() defined to use a many_to_many().
164 __PACKAGE__->many_to_many(roles => 'map_user_role', 'role');
d442cc9f 165
d0496197 167C<lib/MyApp/Schema/>:
d442cc9f 168
d442cc9f 169 #
170 # Set relationships:
171 #
905a3a26 172
d442cc9f 173 # has_many():
174 # args:
175 # 1) Name of relationship, DBIC will create accessor with this name
176 # 2) Name of the model class referenced by this relationship
177 # 3) Column name in *foreign* table
d0496197 178 __PACKAGE__->has_many(map_user_role => 'MyApp::Schema::UserRoles', 'role_id');
d442cc9f 179
d0496197 181C<lib/MyApp/Schema/>:
d442cc9f 182
d442cc9f 183 #
184 # Set relationships:
185 #
905a3a26 186
d442cc9f 187 # belongs_to():
188 # args:
189 # 1) Name of relationship, DBIC will create accessor with this name
190 # 2) Name of the model class referenced by this relationship
191 # 3) Column name in *this* table
d0496197 192 __PACKAGE__->belongs_to(user => 'MyApp::Schema::Users', 'user_id');
905a3a26 193
d442cc9f 194 # belongs_to():
195 # args:
196 # 1) Name of relationship, DBIC will create accessor with this name
197 # 2) Name of the model class referenced by this relationship
198 # 3) Column name in *this* table
d0496197 199 __PACKAGE__->belongs_to(role => 'MyApp::Schema::Roles', 'role_id');
d442cc9f 200
3533daff 201
905a3a26 202The code for these three sets of updates is obviously very similar to
203the edits we made to the C<Books>, C<Authors>, and C<BookAuthors>
3533daff 204classes created in Part 3.
905a3a26 206Note that we do not need to make any change to the
207C<lib/MyApp/> schema file. It simply tells DBIC to
79a529cc 208load all of the result class files it finds in below the
905a3a26 209C<lib/MyApp/Schema> directory, so it will automatically pick
3533daff 210up our new table information.
d442cc9f 211
213=head2 Sanity-Check Reload of Development Server
905a3a26 215We aren't ready to try out the authentication just yet; we only want
216to do a quick check to be sure our model loads correctly. Press
217C<Ctrl-C> to kill the previous server instance (if it's still running)
3533daff 218and restart it:
d442cc9f 219
220 $ script/
222Look for the three new model objects in the startup debug output:
224 ...
225 .-------------------------------------------------------------------+----------.
226 | Class | Type |
227 +-------------------------------------------------------------------+----------+
228 | MyApp::Controller::Books | instance |
229 | MyApp::Controller::Root | instance |
d0496197 230 | MyApp::Model::DB | instance |
231 | MyApp::Model::DB::Author | class |
232 | MyApp::Model::DB::Books | class |
233 | MyApp::Model::DB::BookAuthors | class |
234 | MyApp::Model::DB::Roles | class |
235 | MyApp::Model::DB::Users | class |
236 | MyApp::Model::DB::UserRoles | class |
d442cc9f 237 | MyApp::View::TT | instance |
238 '-------------------------------------------------------------------+----------'
239 ...
79a529cc 241Again, notice that your "result class" classes have been "re-loaded"
3533daff 242by Catalyst under C<MyApp::Model>.
d442cc9f 243
245=head2 Include Authentication and Session Plugins
905a3a26 247Edit C<lib/> and update it as follows (everything below
3533daff 248C<StackTrace> is new):
d442cc9f 249
b411df01 250 use Catalyst qw/
d442cc9f 251 -Debug
252 ConfigLoader
253 Static::Simple
905a3a26 254
d442cc9f 255 StackTrace
905a3a26 256
d442cc9f 257 Authentication
905a3a26 258
d442cc9f 259 Session
260 Session::Store::FastMmap
261 Session::State::Cookie
b411df01 262 /;
d442cc9f 263
905a3a26 264The C<Authentication> plugin supports Authentication while the
265C<Session> plugins are required to maintain state across multiple HTTP
6d0971ad 267
905a3a26 268Note that the only required Authentication class is the main one. This
269is a change that occurred in version 0.09999_01 of the
270C<Authentication> plugin. You B<do not need> to specify a particular
271Authentication::Store or Authentication::Credential plugin. Instead,
272indicate the Store and Credential you want to use in your application
6d0971ad 273configuration (see below).
905a3a26 275Note that there are several options for
278is generally a good choice if you are on Unix; try
279L<Session::Store::File|Catalyst::Plugin::Session::Store::File> if you
280are on Win32) -- consult
281L<Session::Store|Catalyst::Plugin::Session::Store> and its subclasses
3533daff 282for additional information and options (for example to use a database-
283backed session store).
d442cc9f 284
286=head2 Configure Authentication
905a3a26 288Although C<__PACKAGE__-E<gt>config(name =E<gt> 'value');> is still
289supported, newer Catalyst applications tend to place all configuration
290information in C<myapp.conf> and automatically load this information
291into C<MyApp-E<gt>config> using the
292L<ConfigLoader|Catalyst::Plugin::ConfigLoader> plugin.
15e1d0b2 293
905a3a26 294First, as noted in Part 3 of the tutorial, Catalyst has recently
295switched from a default config file format of YAML to
79a529cc 296C<Config::General> (an apache-like format). In case you are using a
297version of Catalyst earlier than v5.7014, delete the C<myapp.yml>, or
298convert it to .conf format using the TIP in
299L<Catalyst::Manual::MoreCatalystBasics>; then simply follow the
300directions below to create a new C<myapp.conf> file.
15e1d0b2 301
905a3a26 302Here, we need to load several parameters that tell
304where to locate information in your database. To do this, edit the
c010ae0d 305C<myapp.conf> file and update it to match:
307 name MyApp
308 <authentication>
309 default_realm dbic
310 <realms>
311 <dbic>
312 <credential>
905a3a26 313 # Note: this first definition would be the same as setting
3533daff 314 # __PACKAGE__->config->{authentication}->{realms}->{dbic}
905a3a26 315 # ->{credential} = 'Password' in lib/
3533daff 316 #
317 # Specify that we are going to do password-based auth
c010ae0d 318 class Password
3533daff 319 # This is the name of the field in the users table with the
320 # password stored in it
c010ae0d 321 password_field password
905a3a26 322 # We are using an unencrypted password for now
c010ae0d 323 password_type clear
324 </credential>
325 <store>
3533daff 326 # Use DBIC to retrieve username, password & role information
c010ae0d 327 class DBIx::Class
905a3a26 328 # This is the model object created by Catalyst::Model::DBIC
d0496197 329 # from your schema (you created 'MyApp::Schema::User' but as
905a3a26 330 # the Catalyst startup debug messages show, it was loaded as
d0496197 331 # 'MyApp::Model::DB::Users').
905a3a26 332 # NOTE: Omit 'MyApp::Model' here just as you would when using
d0496197 333 # '$c->model("DB::Users)'
334 user_class DB::Users
c010ae0d 335 </store>
336 </dbic>
d0496197 337 </realms>
338 </authentication>
d442cc9f 339
340Inline comments in the code above explain how each field is being used.
c010ae0d 342Note that you can use many other config file formats with catalyst.
343See L<Catalyst::Plugin::ConfigLoader|Catalyst::Plugin::ConfigLoader>
344for details.
d442cc9f 345
346=head2 Add Login and Logout Controllers
348Use the Catalyst create script to create two stub controller files:
350 $ script/ controller Login
351 $ script/ controller Logout
d0496197 353B<NOTE:> You could easily use a single controller here. For example,
d442cc9f 354you could have a C<User> controller with both C<login> and C<logout>
355actions. Remember, Catalyst is designed to be very flexible, and leaves
356such matters up to you, the designer and programmer.
905a3a26 358Then open C<lib/MyApp/Controller/>, locate the C<sub index
359:Path :Args(0)> method (or C<sub index : Private> if you are using an
360older version of Catalyst) that was automatically inserted by the
361helpers when we created the Login controller above, and delete this
ae492862 362line:
d442cc9f 363
364 $c->response->body('Matched MyApp::Controller::Login in Login.');
366Then update it to match:
368 =head2 index
905a3a26 369
d442cc9f 370 Login logic
905a3a26 371
d442cc9f 372 =cut
905a3a26 373
ae492862 374 sub index :Path :Args(0) {
d442cc9f 375 my ($self, $c) = @_;
905a3a26 376
d442cc9f 377 # Get the username and password from form
378 my $username = $c->request->params->{username} || "";
379 my $password = $c->request->params->{password} || "";
905a3a26 380
d442cc9f 381 # If the username and password values were found in form
382 if ($username && $password) {
383 # Attempt to log the user in
905a3a26 384 if ($c->authenticate({ username => $username,
5fefca35 385 password => $password } )) {
d442cc9f 386 # If successful, then let them use the application
387 $c->response->redirect($c->uri_for('/books/list'));
388 return;
389 } else {
390 # Set an error message
391 $c->stash->{error_msg} = "Bad username or password.";
392 }
393 }
905a3a26 394
d442cc9f 395 # If either of above don't work out, send to the login page
396 $c->stash->{template} = 'login.tt2';
397 }
399This controller fetches the C<username> and C<password> values from the
905a3a26 400login form and attempts to authenticate the user. If successful, it
401redirects the user to the book list page. If the login fails, the user
402will stay at the login page and receive an error message. If the
403C<username> and C<password> values are not present in the form, the
f632e28b 404user will be taken to the empty login form.
d442cc9f 405
85d49fb6 406Note that we could have used something like C<sub default :Path>,
407however partly for historical reasons, and partly for code clarity it
408is generally recommended only to use C<default> in
409C<MyApp::Controller::Root>, and then mainly to generate the 404 not
410found page for the application.
ae492862 411
905a3a26 412Instead, we are using C<sub base :Path :Args(0) {...}> here to
413specifically match the URL C</login>. C<Path> actions (aka, "literal
414actions") create URI matches relative to the namespace of the
415controller where they are defined. Although C<Path> supports
416arguments that allow relative and absolute paths to be defined, here
417we use an empty C<Path> definition to match on just the name of the
418controller itself. The method name, C<index>, is arbitrary. We make
ae492862 419the match even more specific with the C<:Args(0)> action modifier --
905a3a26 420this forces the match on I<only> C</login>, not
d442cc9f 421C</login/somethingelse>.
905a3a26 423Next, update the corresponding method in
3533daff 424C<lib/MyApp/Controller/> to match:
d442cc9f 425
426 =head2 index
905a3a26 427
d442cc9f 428 Logout logic
905a3a26 429
d442cc9f 430 =cut
905a3a26 431
ae492862 432 sub index :Path :Args(0) {
d442cc9f 433 my ($self, $c) = @_;
905a3a26 434
d442cc9f 435 # Clear the user's state
436 $c->logout;
905a3a26 437
d442cc9f 438 # Send the user to the starting point
439 $c->response->redirect($c->uri_for('/'));
440 }
905a3a26 442As with the login controller, be sure to delete the
14e5ed66 443C<$c-E<gt>response-E<gt>body('Matched MyApp::Controller::Logout in Logout.');>
d442cc9f 444line of the C<sub index>.
447=head2 Add a Login Form TT Template Page
449Create a login form by opening C<root/src/login.tt2> and inserting:
451 [% META title = 'Login' %]
905a3a26 452
d442cc9f 453 <!-- Login form -->
8a7c5151 454 <form method="post" action="[% c.uri_for('/login') %]">
d442cc9f 455 <table>
456 <tr>
457 <td>Username:</td>
458 <td><input type="text" name="username" size="40" /></td>
459 </tr>
460 <tr>
461 <td>Password:</td>
462 <td><input type="password" name="password" size="40" /></td>
463 </tr>
464 <tr>
465 <td colspan="2"><input type="submit" name="submit" value="Submit" /></td>
466 </tr>
467 </table>
468 </form>
471=head2 Add Valid User Check
473We need something that provides enforcement for the authentication
474mechanism -- a I<global> mechanism that prevents users who have not
475passed authentication from reaching any pages except the login page.
476This is generally done via an C<auto> action/method (prior to Catalyst
477v5.66, this sort of thing would go in C<>, but starting in
478v5.66, the preferred location is C<lib/MyApp/Controller/>).
480Edit the existing C<lib/MyApp/Controller/> class file and insert
481the following method:
483 =head2 auto
905a3a26 484
d442cc9f 485 Check if there is a user and, if not, forward to login page
905a3a26 486
d442cc9f 487 =cut
905a3a26 488
d442cc9f 489 # Note that 'auto' runs after 'begin' but before your actions and that
905a3a26 490 # 'auto's "chain" (all from application path to most specific class are run)
d442cc9f 491 # See the 'Actions' section of 'Catalyst::Manual::Intro' for more info.
492 sub auto : Private {
493 my ($self, $c) = @_;
905a3a26 494
d442cc9f 495 # Allow unauthenticated users to reach the login page. This
496 # allows anauthenticated users to reach any action in the Login
497 # controller. To lock it down to a single action, we could use:
498 # if ($c->action eq $c->controller('Login')->action_for('index'))
905a3a26 499 # to only allow unauthenticated access to the 'index' action we
d442cc9f 500 # added above.
501 if ($c->controller eq $c->controller('Login')) {
502 return 1;
503 }
905a3a26 504
d442cc9f 505 # If a user doesn't exist, force login
506 if (!$c->user_exists) {
507 # Dump a log message to the development server debug output
508 $c->log->debug('***Root::auto User not found, forwarding to /login');
509 # Redirect the user to the login page
510 $c->response->redirect($c->uri_for('/login'));
511 # Return 0 to cancel 'post-auto' processing and prevent use of application
512 return 0;
513 }
905a3a26 514
d442cc9f 515 # User found, so return 1 to continue with processing after this 'auto'
516 return 1;
517 }
3533daff 519
905a3a26 520B<Note:> Catalyst provides a number of different types of actions,
521such as C<Local>, C<Regex>, C<Private> and the new C<Path>. You
522should refer to L<Catalyst::Manual::Intro|Catalyst::Manual::Intro> for
523a more detailed explanation, but the following bullet points provide a
3533daff 524quick introduction:
d442cc9f 525
526=over 4
528=item *
905a3a26 530The majority of application have traditionally used C<Local> actions
531for items that respond to user requests and C<Private> actions for
3533daff 532those that do not directly respond to user input.
d442cc9f 533
534=item *
905a3a26 536Newer Catalyst applications tend to use C<Path> actions and the
3533daff 537C<Args> attribute because of their power and flexibility. You can
538specify the path to match relative to the namespace of the current
539module as an argument to C<Path>. For example C<Path('list')> in
905a3a26 540C<lib/MyApp/Controller/> would match on the URL
541C<http://localhost:3000/books/list> but C<Path('/list')> would
3533daff 542match on C<http://localhost:3000/list>.
544=item *
905a3a26 546Automatic "chaining" of actions by the dispatcher is a powerful
547feature that allows multiple methods to handle a single URL. See
3533daff 548L<Catalyst::DispatchType::Chained|Catalyst::DispatchType::Chained>
549for more information on chained actions.
551=item *
553There are five types of build-in C<Private> actions: C<begin>, C<end>,
d442cc9f 554C<default>, C<index>, and C<auto>.
556=item *
558With C<begin>, C<end>, C<default>, C<index> private actions, only the
559most specific action of each type will be called. For example, if you
905a3a26 560define a C<begin> action in your controller it will I<override> a
d442cc9f 561C<begin> action in your application/root controller -- I<only> the
562action in your controller will be called.
564=item *
905a3a26 566Unlike the other actions where only a single method is called for each
567request, I<every> auto action along the chain of namespaces will be
d442cc9f 568called. Each C<auto> action will be called I<from the application/root
569controller down through the most specific class>.
573By placing the authentication enforcement code inside the C<auto> method
574of C<lib/MyApp/Controller/> (or C<lib/>), it will be
575called for I<every> request that is received by the entire application.
578=head2 Displaying Content Only to Authenticated Users
580Let's say you want to provide some information on the login page that
581changes depending on whether the user has authenticated yet. To do
582this, open C<root/src/login.tt2> in your editor and add the following
583lines to the bottom of the file:
585 <p>
586 [%
905a3a26 587 # This code illustrates how certain parts of the TT
d442cc9f 588 # template will only be shown to users who have logged in
589 %]
8a7c5151 590 [% IF c.user_exists %]
591 Please Note: You are already logged in as '[% c.user.username %]'.
592 You can <a href="[% c.uri_for('/logout') %]">logout</a> here.
d442cc9f 593 [% ELSE %]
594 You need to log in to use this application.
595 [% END %]
596 [%#
597 Note that this whole block is a comment because the "#" appears
905a3a26 598 immediate after the "[%" (with no spaces in between). Although it
599 can be a handy way to temporarily "comment out" a whole block of
600 TT code, it's probably a little too subtle for use in "normal"
d442cc9f 601 comments.
602 %]
3533daff 603 </p>
d442cc9f 604
605Although most of the code is comments, the middle few lines provide a
606"you are already logged in" reminder if the user returns to the login
607page after they have already authenticated. For users who have not yet
608authenticated, a "You need to log in..." message is displayed (note the
609use of an IF-THEN-ELSE construct in TT).
612=head2 Try Out Authentication
614Press C<Ctrl-C> to kill the previous server instance (if it's still
615running) and restart it:
617 $ script/
905a3a26 619B<IMPORTANT NOTE:> If you are having issues with authentication on
620Internet Explorer, be sure to check the system clocks on both your
621server and client machines. Internet Explorer is very picky about
25ed8f40 622timestamps for cookies. Note that you can quickly sync an Ubuntu
623system with the following command:
625 sudo ntpdate
d442cc9f 626
627Now trying going to L<http://localhost:3000/books/list> and you should
628be redirected to the login page, hitting Shift+Reload if necessary (the
629"You are already logged in" message should I<not> appear -- if it does,
630click the C<logout> button and try again). Note the C<***Root::auto User
631not found...> debug message in the development server output. Enter
632username C<test01> and password C<mypass>, and you should be taken to
633the Book List page.
635Open C<root/src/books/list.tt2> and add the following lines to the
3533daff 636bottom (below the closing </table> tag):
d442cc9f 637
638 <p>
8a7c5151 639 <a href="[% c.uri_for('/login') %]">Login</a>
640 <a href="[% c.uri_for('form_create') %]">Create</a>
d442cc9f 641 </p>
905a3a26 643Reload your browser and you should now see a "Login" and "Create" links
644at the bottom of the page (as mentioned earlier, you can update template
645files without reloading the development server). Click the first link
646to return to the login page. This time you I<should> see the "You are
d442cc9f 647already logged in" message.
649Finally, click the C<You can logout here> link on the C</login> page.
650You should stay at the login page, but the message should change to "You
651need to log in to use this application."
656In this section we increase the security of our system by converting
657from cleartext passwords to SHA-1 password hashes.
659B<Note:> This section is optional. You can skip it and the rest of the
660tutorial will function normally.
662Note that even with the techniques shown in this section, the browser
663still transmits the passwords in cleartext to your application. We are
664just avoiding the I<storage> of cleartext passwords in the database by
665using a SHA-1 hash. If you are concerned about cleartext passwords
666between the browser and your application, consider using SSL/TLS, made
667easy with the Catalyst plugin Catalyst::Plugin:RequireSSL.
670=head2 Get a SHA-1 Hash for the Password
672Catalyst uses the C<Digest> module to support a variety of hashing
673algorithms. Here we will use SHA-1 (SHA = Secure Hash Algorithm).
674First, we should compute the SHA-1 hash for the "mypass" password we are
675using. The following command-line Perl script provides a "quick and
676dirty" way to do this:
678 $ perl -MDigest::SHA -e 'print Digest::SHA::sha1_hex("mypass"), "\n"'
679 e727d1464ae12436e899a726da5b2f11d8381b26
680 $
905a3a26 682B<Note:> If you are following along in Ubuntu, you will need to install
d0496197 683C<Digest::SHA> with the following command to run the example code above:
905a3a26 685 sudo aptitude install libdigest-sha-perl
d0496197 686
d442cc9f 687B<Note:> You should probably modify this code for production use to
688not read the password from the command line. By having the script
689prompt for the cleartext password, it avoids having the password linger
690in forms such as your C<.bash_history> files (assuming you are using
691BASH as your shell). An example of such a script can be found in
692Appendix 3.
695=head2 Switch to SHA-1 Password Hashes in the Database
697Next, we need to change the C<password> column of our C<users> table to
698store this hash value vs. the existing cleartext password. Open
699C<myapp03.sql> in your editor and enter:
701 --
702 -- Convert passwords to SHA-1 hashes
703 --
704 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 1;
705 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 2;
706 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 3;
708Then use the following command to update the SQLite database:
710 $ sqlite3 myapp.db < myapp03.sql
712B<Note:> We are using SHA-1 hashes here, but many other hashing
713algorithms are supported. See C<Digest> for more information.
716=head2 Enable SHA-1 Hash Passwords in
45d511e0 719Edit C<myapp.conf> and update it to match (the C<password_type> and
d442cc9f 720C<password_hash_type> are new, everything else is the same):
c010ae0d 722 name MyApp
723 <authentication>
724 default_realm dbic
725 <realms>
726 <dbic>
727 <credential>
3533daff 728 # Note this first definition would be the same as setting
729 # __PACKAGE__->config->{authentication}->{realms}->{dbic}
905a3a26 730 # ->{credential} = 'Password' in lib/
3533daff 731 #
732 # Specify that we are going to do password-based auth
c010ae0d 733 class Password
3533daff 734 # This is the name of the field in the users table with the
735 # password stored in it
c010ae0d 736 password_field password
3533daff 737 # Switch to more secure hashed passwords
c010ae0d 738 password_type hashed
3533daff 739 # Use the SHA-1 hashing algorithm
c010ae0d 740 password_hash_type SHA-1
d0496197 741 </credential>
c010ae0d 742 <store>
3533daff 743 # Use DBIC to retrieve username, password & role information
c010ae0d 744 class DBIx::Class
905a3a26 745 # This is the model object created by Catalyst::Model::DBIC
d0496197 746 # from your schema (you created 'MyApp::Schema::User' but as
905a3a26 747 # the Catalyst startup debug messages show, it was loaded as
d0496197 748 # 'MyApp::Model::DB::Users').
905a3a26 749 # NOTE: Omit 'MyApp::Model' here just as you would when using
d0496197 750 # '$c->model("DB::Users)'
751 user_class DB::Users
d0496197 752 </store>
753 </dbic>
754 </realms>
755 </authentication>
d442cc9f 756
757=head2 Try Out the Hashed Passwords
759Press C<Ctrl-C> to kill the previous server instance (if it's still
760running) and restart it:
762 $ script/
764You should now be able to go to L<http://localhost:3000/books/list> and
765login as before. When done, click the "Logout" link on the login page
766(or point your browser at L<http://localhost:3000/logout>).
d442cc9f 768
771As discussed in Part 3 of the tutorial, C<flash> allows you to set
905a3a26 772variables in a way that is very similar to C<stash>, but it will
d442cc9f 773remain set across multiple requests. Once the value is read, it
774is cleared (unless reset). Although C<flash> has nothing to do with
775authentication, it does leverage the same session plugins. Now that
776those plugins are enabled, let's go back and improve the "delete
777and redirect with query parameters" code seen at the end of the
905a3a26 778L<Basic CRUD|Catalyst::Manual::Tutorial::BasicCRUD> part of the
d442cc9f 779tutorial.
781First, open C<lib/MyApp/Controller/> and modify C<sub delete>
3533daff 782to match the following (everything after the model search line of code
783has changed):
d442cc9f 784
905a3a26 785 =head2 delete
d442cc9f 787 Delete a book
905a3a26 788
d442cc9f 789 =cut
905a3a26 790
d442cc9f 791 sub delete : Local {
792 # $id = primary key of book to delete
793 my ($self, $c, $id) = @_;
905a3a26 794
d442cc9f 795 # Search for the book and then delete it
d0496197 796 $c->model('DB::Books')->search({id => $id})->delete_all;
905a3a26 797
d442cc9f 798 # Use 'flash' to save information across requests until it's read
799 $c->flash->{status_msg} = "Book deleted";
905a3a26 800
3533daff 801 # Redirect the user back to the list page
d442cc9f 802 $c->response->redirect($c->uri_for('/books/list'));
803 }
905a3a26 805Next, open C<root/lib/site/layout> and update the TT code to pull from
d442cc9f 806flash vs. the C<status_msg> query parameter:
808 <div id="header">[% PROCESS site/header %]</div>
905a3a26 809
d442cc9f 810 <div id="content">
8a7c5151 811 <span class="message">[% status_msg || c.flash.status_msg %]</span>
d442cc9f 812 <span class="error">[% error_msg %]</span>
813 [% content %]
814 </div>
905a3a26 815
d442cc9f 816 <div id="footer">[% PROCESS site/footer %]</div>
819=head2 Try Out Flash
905a3a26 821Restart the development server and point your browser to
822L<http://localhost:3000/books/url_create/Test/1/4> to create an extra
823several books. Click the "Return to list" link and delete one of the
824"Test" books you just added. The C<flash> mechanism should retain our
3533daff 825"Book deleted" status message across the redirect.
d442cc9f 826
827B<NOTE:> While C<flash> will save information across multiple requests,
828I<it does get cleared the first time it is read>. In general, this is
829exactly what you want -- the C<flash> message will get displayed on
830the next screen where it's appropriate, but it won't "keep showing up"
831after that first time (unless you reset it). Please refer to
832L<Catalyst::Plugin::Session|Catalyst::Plugin::Session> for additional
3533daff 835=head2 Switch To Flash-To-Stash
905a3a26 837Although the a use of flash above is certainly an improvement over the
838C<status_msg> we employed in Part 4 of the tutorial, the C<status_msg
8a7c5151 839|| c.flash.status_msg> statement is a little ugly. A nice
905a3a26 840alternative is to use the C<flash_to_stash> feature that automatically
841copies the content of flash to stash. This makes your code controller
842and template code work regardless of where it was directly access, a
843forward, or a redirect. To enable C<flash_to_stash>, you can either
844set the value in C<lib/> by changing the default
3533daff 845C<__PACKAGE__-E<gt>config> setting to something like:
847 __PACKAGE__->config(
848 name => 'MyApp',
849 session => {flash_to_stash => 1}
850 );
45d511e0 852B<or> add the following to C<myapp.conf>:
3533daff 853
45d511e0 854 <session>
855 flash_to_stash 1
856 </session>
3533daff 857
905a3a26 858The C<__PACKAGE__-E<gt>config> option is probably preferable here
859since it's not something you will want to change at runtime without it
3533daff 860possibly breaking some of your code.
862Then edit C<root/lib/site/layout> and change the C<status_msg> line
863to look like the following:
865 <span class="message">[% status_msg %]</span>
867Restart the development server and go to
905a3a26 868L<http://localhost:3000/books/list> in your browser. Delete another
3533daff 869of the "Test" books you added in the previous step. Flash should still
870maintain the status message across the redirect even though you are no
8a7c5151 871longer explicitly accessing C<c.flash>.
3533daff 872
d442cc9f 873
874=head1 AUTHOR
876Kennedy Clark, C<>
878Please report any errors, issues or suggestions to the author. The
879most recent version of the Catalyst Tutorial can be found at
d712b826 880L<>.
d442cc9f 881
45c7830f 882Copyright 2006-2008, Kennedy Clark, under Creative Commons License
d442cc9f 883(L<>).