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NAME

Mojolicious::Plugin::Authorization - A plugin to make Authorization a bit easier

VERSION

version 1.06

SYNOPSIS

    use Mojolicious::Plugin::Authorization
    $self->plugin('Authorization' => {
        'has_priv'    => sub { ... },
        'is_role'     => sub { ... },
        'user_privs'  => sub { ... },
        'user_role'   => sub { ... },
        'fail_render' => { status => 401, json => { ... } },
    });
    if ($self->has_priv('delete_all', { optional => 'extra data stuff' })) {
        ...
    }

DESCRIPTION

A very simple API implementation of role-based access control (RBAC). This plugin is only an API you will have to do all the work of setting up your roles and privileges and then provide four subs that are used by the plugin. The plugin expects that the current session will be used to get the role its privileges. It also assumes that you have already been authenticated and your role set. That is about it you are free to implement any system you like.

METHODS

has_priv('privilege', $extra_data) or has_privilege('privilege', $extra_data)

'has_priv' and 'has_privilege' will use the supplied has_priv subroutine ref to check if the current session has the given privilege. Returns true when the session has the privilege or false otherwise. You can pass additional data along in the extra_data hashref and it will be passed to your has_priv subroutine as-is.

is('role',$extra_data) or is_role('role',$extra_data)

'is' and 'is_role' will use the supplied is_role subroutine ref to check if the current session is the given role. Returns true when the session has privilege or false otherwise. You can pass additional data along in the extra_data hashref and it will be passed to your is_role subroutine as-is.

privileges($extra_data)

'privileges' will use the supplied user_privs subroutine ref and return the privileges of the current session. You can pass additional data along in the extra_data hashref and it will be passed to your user_privs subroutine as-is. The returned data is dependent on the supplied user_privs subroutine.

role($extra_data)

'role' will use the supplied user_role subroutine ref and return the role of the current session. You can pass additional data along in the extra_data hashref and it will be passed to your user_role subroutine as-is. The returned data is dependent on the supplied user_role subroutine.

CONFIGURATION

The following options must be set for the plugin:

has_priv (REQUIRED) A coderef for checking to see if the current session has a privilege (see "HAS PRIV").
is_role (REQUIRED) A coderef for checking to see if the current session is a certain role (see "IS / IS ROLE").
user_privs (REQUIRED) A coderef for returning the privileges of the current session (see "PRIVILEGES").
user_role (REQUIRED) A coderef for returning the role of the current session (see "ROLE").

The following options are not required but allow greater control:

fail_render (OPTIONAL) A hashref for setting the status code and rendering json/text/etc when routing fails (see "ROUTING VIA CALLBACK").

HAS PRIV / HAS PRIVILEGE

'has_priv' is used when you need to confirm that the current session has the given privilege. The coderef you pass to the has_priv configuration key has the following signature:

    sub {
        my ($app, $privilege,$extradata) = @_;
        ...
    }

You must return either 0 for a fail and 1 for a pass. This allows ROUTING VIA CONDITION to work correctly.

IS / IS ROLE

'is' / 'is_role' is used when you need to confirm that the current session is set to the given role. The coderef you pass to the is_role configuration key has the following signature:

    sub {
        my ($app, $role, $extradata) = @_;
        ...
        return $role;
    }

You must return either 0 for a fail and 1 for a pass. This allows ROUTING VIA CONDITION to work correctly.

PRIVILEGES

'privileges' is used when you need to get all the privileges of the current session. The coderef you pass to the user_privs configuration key has the following signature:

    sub {
        my ($app,$extradata) = @_;
        ...
        return $privileges;
    }

You can return anything you want. It would normally be an arrayref of privileges but you are free to return a scalar, hashref, arrayref, blessed object, or undef.

ROLE

'role' is used when you need to get the role of the current session. The coderef you pass to the user_privs configuration key has the following signature:

    sub {
        my ($app,$extradata) = @_;
        ...
        return $role;
    }

You can return anything you want. It would normally be just a scalar but you are free to return a scalar, hashref, arrayref, blessed object, or undef.

EXAMPLES

For a code example using this, see the t/01-functional.t test, it uses Mojolicious::Lite and this plugin.

ROUTING VIA CONDITION

This plugin also exports a routing condition you can use in order to limit access to certain documents to only sessions that have a privilege.

    $r->route('/delete_all')->requires(has_priv => 'delete_all')->to('mycontroller#delete_all');
    $r->route('/delete_all')->requires(has_priv => ['delete_all', $extradata])->to('mycontroller#delete_all');
    my $delete_all_only = $r->route('/members')->requires(has_priv => 'delete_all')->to('members#delete_all');
    $delete_all_only->route('delete')->to('members#delete_all');

If the session does not have the 'delete_all' privilege, these routes will not be considered by the dispatcher and unless you have set up a catch-all route, a 404 Not Found will be generated instead.

Another condition you can use to limit access to certain documents to only those sessions that have a role.

    $r->route('/view_all')->requires(is => 'ADMIN')->to('mycontroller#view_all');
    $r->route('/view_all')->requires(is => ['ADMIN', $extradata])->to('mycontroller#view_all');
    my $view_all_only = $r->route('/members')->requires(is => 'view_all')->to('members#view_all');
    $view_all_only->route('view')->to('members#view_all');

If the session is not the 'ADMIN' role, these routes will not be considered by the dispatcher and unless you have set up a catch-all route, a 404 Not Found will be generated instead. This behavior is similar to the "has" condition.

ROUTING VIA CALLBACK

It is not recommended to route un-authorized requests to anything but a 404 page. If you do route to some sort of 'You are not allowed page' you are telling a hacker that the URL was correct while the 404 tells them nothing. This is just my opinion.

However in the case of publicly documented APIs returning a 404 when priv/role checks fails can confuse users, so you can override the default 404 status on failure by supplying a 'fail_render' value in the plugin config. This will be passed to the Mojolicious ->render method when the has_priv/is/is_role routing fails. For example, to return a status code of 401 with JSON:

    fail_render => { status => 401, json => { error => 'Denied' } },

SEE ALSO

Mojolicious::Sessions, Mojocast 3: Authorization

AUTHOR

John Scoles, <byterock at hotmail.com>

BUGS / CONTRIBUTING

Please report any bugs or feature requests through the web interface at https://github.com/byterock/mojolicious-plugin-authorization/issues.

SUPPORT

You can find documentation for this module with the perldoc command. perldoc Mojolicious::Plugin::Authorization You can also look for information at:

ACKNOWLEDGEMENTS

Ben van Staveren (madcat)

    -   For 'Mojolicious::Plugin::Authentication' which I used as a guide in writing up this one.

Chuck Finley

    -   For staring me off on this.

Abhijit Menon-Sen

    -   For the routing suggestions

Roland Lammel

    -   For some other good suggestions

Lee Johnson

    -   For the latest updates for version 1.04
    

Matt Altus

    -   For the Allow extra data via conditional routing enhancement 
    

LICENSE AND COPYRIGHT

Copyright 2012 John Scoles. This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License. See http://dev.perl.org/licenses/ for more information.