remove MyApp::auto
[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
905a3a26 335 # This is the name of the field in your 'users' table that
3533daff 336 # contains the user's name
c010ae0d 337 id_field username
338 </store>
339 </dbic>
d0496197 340 </realms>
341 </authentication>
d442cc9f 342
343Inline comments in the code above explain how each field is being used.
c010ae0d 345Note that you can use many other config file formats with catalyst.
346See L<Catalyst::Plugin::ConfigLoader|Catalyst::Plugin::ConfigLoader>
347for details.
d442cc9f 348
349=head2 Add Login and Logout Controllers
351Use the Catalyst create script to create two stub controller files:
353 $ script/ controller Login
354 $ script/ controller Logout
d0496197 356B<NOTE:> You could easily use a single controller here. For example,
d442cc9f 357you could have a C<User> controller with both C<login> and C<logout>
358actions. Remember, Catalyst is designed to be very flexible, and leaves
359such matters up to you, the designer and programmer.
905a3a26 361Then open C<lib/MyApp/Controller/>, locate the C<sub index
362:Path :Args(0)> method (or C<sub index : Private> if you are using an
363older version of Catalyst) that was automatically inserted by the
364helpers when we created the Login controller above, and delete this
ae492862 365line:
d442cc9f 366
367 $c->response->body('Matched MyApp::Controller::Login in Login.');
369Then update it to match:
371 =head2 index
905a3a26 372
d442cc9f 373 Login logic
905a3a26 374
d442cc9f 375 =cut
905a3a26 376
ae492862 377 sub index :Path :Args(0) {
d442cc9f 378 my ($self, $c) = @_;
905a3a26 379
d442cc9f 380 # Get the username and password from form
381 my $username = $c->request->params->{username} || "";
382 my $password = $c->request->params->{password} || "";
905a3a26 383
d442cc9f 384 # If the username and password values were found in form
385 if ($username && $password) {
386 # Attempt to log the user in
905a3a26 387 if ($c->authenticate({ username => $username,
f632e28b 388 password => $password} )) {
d442cc9f 389 # If successful, then let them use the application
390 $c->response->redirect($c->uri_for('/books/list'));
391 return;
392 } else {
393 # Set an error message
394 $c->stash->{error_msg} = "Bad username or password.";
395 }
396 }
905a3a26 397
d442cc9f 398 # If either of above don't work out, send to the login page
399 $c->stash->{template} = 'login.tt2';
400 }
402This controller fetches the C<username> and C<password> values from the
905a3a26 403login form and attempts to authenticate the user. If successful, it
404redirects the user to the book list page. If the login fails, the user
405will stay at the login page and receive an error message. If the
406C<username> and C<password> values are not present in the form, the
f632e28b 407user will be taken to the empty login form.
d442cc9f 408
85d49fb6 409Note that we could have used something like C<sub default :Path>,
410however partly for historical reasons, and partly for code clarity it
411is generally recommended only to use C<default> in
412C<MyApp::Controller::Root>, and then mainly to generate the 404 not
413found page for the application.
ae492862 414
905a3a26 415Instead, we are using C<sub base :Path :Args(0) {...}> here to
416specifically match the URL C</login>. C<Path> actions (aka, "literal
417actions") create URI matches relative to the namespace of the
418controller where they are defined. Although C<Path> supports
419arguments that allow relative and absolute paths to be defined, here
420we use an empty C<Path> definition to match on just the name of the
421controller itself. The method name, C<index>, is arbitrary. We make
ae492862 422the match even more specific with the C<:Args(0)> action modifier --
905a3a26 423this forces the match on I<only> C</login>, not
d442cc9f 424C</login/somethingelse>.
905a3a26 426Next, update the corresponding method in
3533daff 427C<lib/MyApp/Controller/> to match:
d442cc9f 428
429 =head2 index
905a3a26 430
d442cc9f 431 Logout logic
905a3a26 432
d442cc9f 433 =cut
905a3a26 434
ae492862 435 sub index :Path :Args(0) {
d442cc9f 436 my ($self, $c) = @_;
905a3a26 437
d442cc9f 438 # Clear the user's state
439 $c->logout;
905a3a26 440
d442cc9f 441 # Send the user to the starting point
442 $c->response->redirect($c->uri_for('/'));
443 }
905a3a26 445As with the login controller, be sure to delete the
14e5ed66 446C<$c-E<gt>response-E<gt>body('Matched MyApp::Controller::Logout in Logout.');>
d442cc9f 447line of the C<sub index>.
450=head2 Add a Login Form TT Template Page
452Create a login form by opening C<root/src/login.tt2> and inserting:
454 [% META title = 'Login' %]
905a3a26 455
d442cc9f 456 <!-- Login form -->
8a7c5151 457 <form method="post" action="[% c.uri_for('/login') %]">
d442cc9f 458 <table>
459 <tr>
460 <td>Username:</td>
461 <td><input type="text" name="username" size="40" /></td>
462 </tr>
463 <tr>
464 <td>Password:</td>
465 <td><input type="password" name="password" size="40" /></td>
466 </tr>
467 <tr>
468 <td colspan="2"><input type="submit" name="submit" value="Submit" /></td>
469 </tr>
470 </table>
471 </form>
474=head2 Add Valid User Check
476We need something that provides enforcement for the authentication
477mechanism -- a I<global> mechanism that prevents users who have not
478passed authentication from reaching any pages except the login page.
479This is generally done via an C<auto> action/method (prior to Catalyst
480v5.66, this sort of thing would go in C<>, but starting in
481v5.66, the preferred location is C<lib/MyApp/Controller/>).
483Edit the existing C<lib/MyApp/Controller/> class file and insert
484the following method:
486 =head2 auto
905a3a26 487
d442cc9f 488 Check if there is a user and, if not, forward to login page
905a3a26 489
d442cc9f 490 =cut
905a3a26 491
d442cc9f 492 # Note that 'auto' runs after 'begin' but before your actions and that
905a3a26 493 # 'auto's "chain" (all from application path to most specific class are run)
d442cc9f 494 # See the 'Actions' section of 'Catalyst::Manual::Intro' for more info.
495 sub auto : Private {
496 my ($self, $c) = @_;
905a3a26 497
d442cc9f 498 # Allow unauthenticated users to reach the login page. This
499 # allows anauthenticated users to reach any action in the Login
500 # controller. To lock it down to a single action, we could use:
501 # if ($c->action eq $c->controller('Login')->action_for('index'))
905a3a26 502 # to only allow unauthenticated access to the 'index' action we
d442cc9f 503 # added above.
504 if ($c->controller eq $c->controller('Login')) {
505 return 1;
506 }
905a3a26 507
d442cc9f 508 # If a user doesn't exist, force login
509 if (!$c->user_exists) {
510 # Dump a log message to the development server debug output
511 $c->log->debug('***Root::auto User not found, forwarding to /login');
512 # Redirect the user to the login page
513 $c->response->redirect($c->uri_for('/login'));
514 # Return 0 to cancel 'post-auto' processing and prevent use of application
515 return 0;
516 }
905a3a26 517
d442cc9f 518 # User found, so return 1 to continue with processing after this 'auto'
519 return 1;
520 }
3533daff 522
905a3a26 523B<Note:> Catalyst provides a number of different types of actions,
524such as C<Local>, C<Regex>, C<Private> and the new C<Path>. You
525should refer to L<Catalyst::Manual::Intro|Catalyst::Manual::Intro> for
526a more detailed explanation, but the following bullet points provide a
3533daff 527quick introduction:
d442cc9f 528
529=over 4
531=item *
905a3a26 533The majority of application have traditionally used C<Local> actions
534for items that respond to user requests and C<Private> actions for
3533daff 535those that do not directly respond to user input.
d442cc9f 536
537=item *
905a3a26 539Newer Catalyst applications tend to use C<Path> actions and the
3533daff 540C<Args> attribute because of their power and flexibility. You can
541specify the path to match relative to the namespace of the current
542module as an argument to C<Path>. For example C<Path('list')> in
905a3a26 543C<lib/MyApp/Controller/> would match on the URL
544C<http://localhost:3000/books/list> but C<Path('/list')> would
3533daff 545match on C<http://localhost:3000/list>.
547=item *
905a3a26 549Automatic "chaining" of actions by the dispatcher is a powerful
550feature that allows multiple methods to handle a single URL. See
3533daff 551L<Catalyst::DispatchType::Chained|Catalyst::DispatchType::Chained>
552for more information on chained actions.
554=item *
556There are five types of build-in C<Private> actions: C<begin>, C<end>,
d442cc9f 557C<default>, C<index>, and C<auto>.
559=item *
561With C<begin>, C<end>, C<default>, C<index> private actions, only the
562most specific action of each type will be called. For example, if you
905a3a26 563define a C<begin> action in your controller it will I<override> a
d442cc9f 564C<begin> action in your application/root controller -- I<only> the
565action in your controller will be called.
567=item *
905a3a26 569Unlike the other actions where only a single method is called for each
570request, I<every> auto action along the chain of namespaces will be
d442cc9f 571called. Each C<auto> action will be called I<from the application/root
572controller down through the most specific class>.
576By placing the authentication enforcement code inside the C<auto> method
577of C<lib/MyApp/Controller/> (or C<lib/>), it will be
578called for I<every> request that is received by the entire application.
581=head2 Displaying Content Only to Authenticated Users
583Let's say you want to provide some information on the login page that
584changes depending on whether the user has authenticated yet. To do
585this, open C<root/src/login.tt2> in your editor and add the following
586lines to the bottom of the file:
588 <p>
589 [%
905a3a26 590 # This code illustrates how certain parts of the TT
d442cc9f 591 # template will only be shown to users who have logged in
592 %]
8a7c5151 593 [% IF c.user_exists %]
594 Please Note: You are already logged in as '[% c.user.username %]'.
595 You can <a href="[% c.uri_for('/logout') %]">logout</a> here.
d442cc9f 596 [% ELSE %]
597 You need to log in to use this application.
598 [% END %]
599 [%#
600 Note that this whole block is a comment because the "#" appears
905a3a26 601 immediate after the "[%" (with no spaces in between). Although it
602 can be a handy way to temporarily "comment out" a whole block of
603 TT code, it's probably a little too subtle for use in "normal"
d442cc9f 604 comments.
605 %]
3533daff 606 </p>
d442cc9f 607
608Although most of the code is comments, the middle few lines provide a
609"you are already logged in" reminder if the user returns to the login
610page after they have already authenticated. For users who have not yet
611authenticated, a "You need to log in..." message is displayed (note the
612use of an IF-THEN-ELSE construct in TT).
615=head2 Try Out Authentication
617Press C<Ctrl-C> to kill the previous server instance (if it's still
618running) and restart it:
620 $ script/
905a3a26 622B<IMPORTANT NOTE:> If you are having issues with authentication on
623Internet Explorer, be sure to check the system clocks on both your
624server and client machines. Internet Explorer is very picky about
25ed8f40 625timestamps for cookies. Note that you can quickly sync an Ubuntu
626system with the following command:
628 sudo ntpdate
d442cc9f 629
630Now trying going to L<http://localhost:3000/books/list> and you should
631be redirected to the login page, hitting Shift+Reload if necessary (the
632"You are already logged in" message should I<not> appear -- if it does,
633click the C<logout> button and try again). Note the C<***Root::auto User
634not found...> debug message in the development server output. Enter
635username C<test01> and password C<mypass>, and you should be taken to
636the Book List page.
638Open C<root/src/books/list.tt2> and add the following lines to the
3533daff 639bottom (below the closing </table> tag):
d442cc9f 640
641 <p>
8a7c5151 642 <a href="[% c.uri_for('/login') %]">Login</a>
643 <a href="[% c.uri_for('form_create') %]">Create</a>
d442cc9f 644 </p>
905a3a26 646Reload your browser and you should now see a "Login" and "Create" links
647at the bottom of the page (as mentioned earlier, you can update template
648files without reloading the development server). Click the first link
649to return to the login page. This time you I<should> see the "You are
d442cc9f 650already logged in" message.
652Finally, click the C<You can logout here> link on the C</login> page.
653You should stay at the login page, but the message should change to "You
654need to log in to use this application."
659In this section we increase the security of our system by converting
660from cleartext passwords to SHA-1 password hashes.
662B<Note:> This section is optional. You can skip it and the rest of the
663tutorial will function normally.
665Note that even with the techniques shown in this section, the browser
666still transmits the passwords in cleartext to your application. We are
667just avoiding the I<storage> of cleartext passwords in the database by
668using a SHA-1 hash. If you are concerned about cleartext passwords
669between the browser and your application, consider using SSL/TLS, made
670easy with the Catalyst plugin Catalyst::Plugin:RequireSSL.
673=head2 Get a SHA-1 Hash for the Password
675Catalyst uses the C<Digest> module to support a variety of hashing
676algorithms. Here we will use SHA-1 (SHA = Secure Hash Algorithm).
677First, we should compute the SHA-1 hash for the "mypass" password we are
678using. The following command-line Perl script provides a "quick and
679dirty" way to do this:
681 $ perl -MDigest::SHA -e 'print Digest::SHA::sha1_hex("mypass"), "\n"'
682 e727d1464ae12436e899a726da5b2f11d8381b26
683 $
905a3a26 685B<Note:> If you are following along in Ubuntu, you will need to install
d0496197 686C<Digest::SHA> with the following command to run the example code above:
905a3a26 688 sudo aptitude install libdigest-sha-perl
d0496197 689
d442cc9f 690B<Note:> You should probably modify this code for production use to
691not read the password from the command line. By having the script
692prompt for the cleartext password, it avoids having the password linger
693in forms such as your C<.bash_history> files (assuming you are using
694BASH as your shell). An example of such a script can be found in
695Appendix 3.
698=head2 Switch to SHA-1 Password Hashes in the Database
700Next, we need to change the C<password> column of our C<users> table to
701store this hash value vs. the existing cleartext password. Open
702C<myapp03.sql> in your editor and enter:
704 --
705 -- Convert passwords to SHA-1 hashes
706 --
707 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 1;
708 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 2;
709 UPDATE users SET password = 'e727d1464ae12436e899a726da5b2f11d8381b26' WHERE id = 3;
711Then use the following command to update the SQLite database:
713 $ sqlite3 myapp.db < myapp03.sql
715B<Note:> We are using SHA-1 hashes here, but many other hashing
716algorithms are supported. See C<Digest> for more information.
719=head2 Enable SHA-1 Hash Passwords in
45d511e0 722Edit C<myapp.conf> and update it to match (the C<password_type> and
d442cc9f 723C<password_hash_type> are new, everything else is the same):
c010ae0d 725 name MyApp
726 <authentication>
727 default_realm dbic
728 <realms>
729 <dbic>
730 <credential>
3533daff 731 # Note this first definition would be the same as setting
732 # __PACKAGE__->config->{authentication}->{realms}->{dbic}
905a3a26 733 # ->{credential} = 'Password' in lib/
3533daff 734 #
735 # Specify that we are going to do password-based auth
c010ae0d 736 class Password
3533daff 737 # This is the name of the field in the users table with the
738 # password stored in it
c010ae0d 739 password_field password
3533daff 740 # Switch to more secure hashed passwords
c010ae0d 741 password_type hashed
3533daff 742 # Use the SHA-1 hashing algorithm
c010ae0d 743 password_hash_type SHA-1
d0496197 744 </credential>
c010ae0d 745 <store>
3533daff 746 # Use DBIC to retrieve username, password & role information
c010ae0d 747 class DBIx::Class
905a3a26 748 # This is the model object created by Catalyst::Model::DBIC
d0496197 749 # from your schema (you created 'MyApp::Schema::User' but as
905a3a26 750 # the Catalyst startup debug messages show, it was loaded as
d0496197 751 # 'MyApp::Model::DB::Users').
905a3a26 752 # NOTE: Omit 'MyApp::Model' here just as you would when using
d0496197 753 # '$c->model("DB::Users)'
754 user_class DB::Users
905a3a26 755 # This is the name of the field in your 'users' table that
3533daff 756 # contains the user's name
c010ae0d 757 id_field username
d0496197 758 </store>
759 </dbic>
760 </realms>
761 </authentication>
d442cc9f 762
763=head2 Try Out the Hashed Passwords
765Press C<Ctrl-C> to kill the previous server instance (if it's still
766running) and restart it:
768 $ script/
770You should now be able to go to L<http://localhost:3000/books/list> and
771login as before. When done, click the "Logout" link on the login page
772(or point your browser at L<http://localhost:3000/logout>).
d442cc9f 774
777As discussed in Part 3 of the tutorial, C<flash> allows you to set
905a3a26 778variables in a way that is very similar to C<stash>, but it will
d442cc9f 779remain set across multiple requests. Once the value is read, it
780is cleared (unless reset). Although C<flash> has nothing to do with
781authentication, it does leverage the same session plugins. Now that
782those plugins are enabled, let's go back and improve the "delete
783and redirect with query parameters" code seen at the end of the
905a3a26 784L<Basic CRUD|Catalyst::Manual::Tutorial::BasicCRUD> part of the
d442cc9f 785tutorial.
787First, open C<lib/MyApp/Controller/> and modify C<sub delete>
3533daff 788to match the following (everything after the model search line of code
789has changed):
d442cc9f 790
905a3a26 791 =head2 delete
d442cc9f 793 Delete a book
905a3a26 794
d442cc9f 795 =cut
905a3a26 796
d442cc9f 797 sub delete : Local {
798 # $id = primary key of book to delete
799 my ($self, $c, $id) = @_;
905a3a26 800
d442cc9f 801 # Search for the book and then delete it
d0496197 802 $c->model('DB::Books')->search({id => $id})->delete_all;
905a3a26 803
d442cc9f 804 # Use 'flash' to save information across requests until it's read
805 $c->flash->{status_msg} = "Book deleted";
905a3a26 806
3533daff 807 # Redirect the user back to the list page
d442cc9f 808 $c->response->redirect($c->uri_for('/books/list'));
809 }
905a3a26 811Next, open C<root/lib/site/layout> and update the TT code to pull from
d442cc9f 812flash vs. the C<status_msg> query parameter:
814 <div id="header">[% PROCESS site/header %]</div>
905a3a26 815
d442cc9f 816 <div id="content">
8a7c5151 817 <span class="message">[% status_msg || c.flash.status_msg %]</span>
d442cc9f 818 <span class="error">[% error_msg %]</span>
819 [% content %]
820 </div>
905a3a26 821
d442cc9f 822 <div id="footer">[% PROCESS site/footer %]</div>
825=head2 Try Out Flash
905a3a26 827Restart the development server and point your browser to
828L<http://localhost:3000/books/url_create/Test/1/4> to create an extra
829several books. Click the "Return to list" link and delete one of the
830"Test" books you just added. The C<flash> mechanism should retain our
3533daff 831"Book deleted" status message across the redirect.
d442cc9f 832
833B<NOTE:> While C<flash> will save information across multiple requests,
834I<it does get cleared the first time it is read>. In general, this is
835exactly what you want -- the C<flash> message will get displayed on
836the next screen where it's appropriate, but it won't "keep showing up"
837after that first time (unless you reset it). Please refer to
838L<Catalyst::Plugin::Session|Catalyst::Plugin::Session> for additional
3533daff 841=head2 Switch To Flash-To-Stash
905a3a26 843Although the a use of flash above is certainly an improvement over the
844C<status_msg> we employed in Part 4 of the tutorial, the C<status_msg
8a7c5151 845|| c.flash.status_msg> statement is a little ugly. A nice
905a3a26 846alternative is to use the C<flash_to_stash> feature that automatically
847copies the content of flash to stash. This makes your code controller
848and template code work regardless of where it was directly access, a
849forward, or a redirect. To enable C<flash_to_stash>, you can either
850set the value in C<lib/> by changing the default
3533daff 851C<__PACKAGE__-E<gt>config> setting to something like:
853 __PACKAGE__->config(
854 name => 'MyApp',
855 session => {flash_to_stash => 1}
856 );
45d511e0 858B<or> add the following to C<myapp.conf>:
3533daff 859
45d511e0 860 <session>
861 flash_to_stash 1
862 </session>
3533daff 863
905a3a26 864The C<__PACKAGE__-E<gt>config> option is probably preferable here
865since it's not something you will want to change at runtime without it
3533daff 866possibly breaking some of your code.
868Then edit C<root/lib/site/layout> and change the C<status_msg> line
869to look like the following:
871 <span class="message">[% status_msg %]</span>
873Restart the development server and go to
905a3a26 874L<http://localhost:3000/books/list> in your browser. Delete another
3533daff 875of the "Test" books you added in the previous step. Flash should still
876maintain the status message across the redirect even though you are no
8a7c5151 877longer explicitly accessing C<c.flash>.
3533daff 878
d442cc9f 879
880=head1 AUTHOR
882Kennedy Clark, C<>
884Please report any errors, issues or suggestions to the author. The
885most recent version of the Catalyst Tutorial can be found at
d712b826 886L<>.
d442cc9f 887
45c7830f 888Copyright 2006-2008, Kennedy Clark, under Creative Commons License
d442cc9f 889(L<>).