NAME

NAME
Dancer::Plugin::Auth::Tiny - Require logged-in user for specified routes

VERSION
version 0.002

SYNOPSIS
use Dancer::Plugin::Auth::Tiny;

get '/private' => needs login => sub { ... };

get '/login' => sub {
# put 'return_url' in a hidden form field
template 'login' => { return_url => params->{return_url} };
};

post '/login' => sub {
if ( _is_valid( params->{user}, params->{password} ) ) {
session user => params->{user},
return redirect params->{return_url} || '/';
}
else {
template 'login' => { error => "invalid username or password" };
}
};

sub _is_valid { ... } # this is up to you

DESCRIPTION
This Dancer plugin provides an extremely simple way of requiring that a
user be logged in before allowing access to certain routes.

It is not "Tiny" in the usual CPAN sense, but it is "Tiny" with respect
to Dancer authentication plugins. It provides very simple sugar to wrap
route handlers with an authentication closure.

The plugin provides the "needs" keyword and a default "login" wrapper
that you can use like this:

get '/private' => needs login => $coderef;

The code above is roughly equivalent to this:

get '/private' => sub {
if ( session 'user' ) {
goto $coderef;
}
else {
return redirect uri_for( '/login',
{ return_url => uri_for( request->path, request->params ) } );
}
};

It is up to you to provide the '/login' route, handle actual
authentication, and set "user" session variable if login is successful.

If the original request contains a parameter in the "passthrough" list,
it will be added to the login query. For example,
"http://example.com/private?user=dagolden" will be redirected as
"http://example.com/login?user=dagolden&return_url=...". This
facilitates pre-populating a login form.

CONFIGURATION
You may override any of these settings:

* "login_route: /login" -- defines where a protected route is
redirected

* "logged_in_key: user" -- defines the session key that must be true
to indicate a logged-in user

* "callback_key: return_url" -- defines the parameter key with the
original request URL that is passed to the login route

* "passthrough: - user" -- a list of parameters that should be passed
through to the login handler

EXTENDING
The class method "extend" may be used to add (or override)
authentication criteria. For example, to add a check for the "session
'is_admin'" key:

Dancer::Plugin::Auth::Tiny->extend(
admin => sub {
my ($coderef) = @_;
return sub {
if ( session "is_admin" ) {
goto $coderef;
}
else {
redirect '/access_denied';
}
};
}
);

get '/super_secret' => needs admin => sub { ... };

It takes key/value pairs where the value must be a closure generator
that wraps arguments passed to "needs".

You could pass additional arguments before the code reference like so:

# don't conflict with Dancer's any()
use Syntax::Keyword::Junction 'any' => { -as => 'any_of' };

Dancer::Plugin::Auth::Tiny->extend(
any_role => sub {
my $coderef = pop;
my @requested_roles = @_;
return sub {
my @user_roles = @{ session("roles") || [] };
if ( any_of(@requested_roles) eq any_of(@user_roles) {
goto $coderef;
}
else {
redirect '/access_denied';
}
};
}
);

get '/parental' => needs any_role => qw/mom dad/ => sub { ... };

SEE ALSO
For more complex Dancer authentication, see:

* Dancer::Plugin::Auth::Extensible

* Dancer::Plugin::Auth::RBAC

For password authentication algorithms for your own '/login' handler,
see:

* Auth::Passphrase

* Dancer::Plugin::Passphrase

ACKNOWLEDGMENTS
This simplified Auth module was inspired by
Dancer::Plugin::Auth::Extensible by David Precious and discussions about
its API by member of the Dancer Users mailing list.

SUPPORT
Bugs / Feature Requests
Please report any bugs or feature requests through the issue tracker at
<https://github.com/dagolden/dancer-plugin-auth-tiny/issues>. You will
be notified automatically of any progress on your issue.

Source Code
This is open source software. The code repository is available for
public review and contribution under the terms of the license.

<https://github.com/dagolden/dancer-plugin-auth-tiny>

git clone git://github.com/dagolden/dancer-plugin-auth-tiny.git

AUTHOR
David Golden <[email protected]>

COPYRIGHT AND LICENSE
This software is Copyright (c) 2012 by David Golden.

This is free software, licensed under:

The Apache License, Version 2.0, January 2004