NAME
Dancer2::Plugin::Auth::OAuth - OAuth for your Dancer2 app
SYNOPSIS
# just 'use' the plugin, that's all.
use Dancer2::Plugin::Auth::OAuth;
DESCRIPTION
Dancer2::Plugin::Auth::OAuth is a Dancer2 plugin which tries to make
OAuth authentication easy.
The module is highly influenced by Plack::Middleware::OAuth and Dancer
1 OAuth modules, but unlike the Dancer 1 versions, this plugin only
needs configuration (look mom, no code needed!). It automatically sets
up the needed routes (defaults to /auth/$provider and
/auth/$provider/callback). So if you define the Twitter provider in
your config, you should automatically get /auth/twitter and
/auth/twitter/callback.
After a successful OAuth dance, the user info is stored in the session
"oauth". What you do with it afterwards is up to you. Please note the
user will continue to be authenticated until the Dancer2 session has
expired, whenever that might be.
CONFIGURATION
The plugin comes with support for Facebook, Google, Twitter, GitHub,
Stack Exchange, LinkedIn and several more (other providers aren't hard
to add, send me a pull request when you add more!).
All it takes to use OAuth authentication for a given provider, is to
add the configuration for it. You don't need anything else.
The YAML below shows all available options.
plugins:
"Auth::OAuth":
reauth_on_refresh_fail: 0 [*]
prefix: /auth [*]
success_url: / [*]
error_url: / [*]
providers:
Facebook:
tokens:
client_id: your_client_id
client_secret: your_client_secret
fields: id,email,name,gender,picture
# Original default Facebook scope was 'email,public_profile,user_friends'
# Since March 2018 'user_friends' requires an app review.
# Add the following three lines if you don't have it reviewed.
query_params:
authorize:
scope: email,public_profile
Google:
tokens:
client_id: your_client_id
client_secret: your_client_secret
AzureAD:
tokens:
client_id: your_client_id
client_secret: your_client_secret
Twitter:
tokens:
consumer_key: your_consumer_token
consumer_secret: your_consumer_secret
Github:
tokens:
client_id: your_client_id
client_secret: your_client_secret
Stackexchange:
tokens:
client_id: your_client_id
client_secret: your_client_secret
key: your_key
site: stackoverflow
Linkedin:
tokens:
client_id: your_client_id
client_secret: your_client_secret
fields: id,num-connections,picture-url,email-address
VKontakte: # https://vk.com
tokens:
client_id: your_client_id
client_secret: your_client_secret
fields: 'first_name,last_name,about,bdate,city,country,photo_max_orig,sex,site'
api_version: '5.8'
Odnoklassniki: # https://ok.ru
tokens:
client_id: your_client_id
client_secret: your_client_secret
application_key: your_application_key
method: 'users.getCurrentUser'
format: 'json'
fields: 'email,name,gender,birthday,location,uid,pic_full'
MailRU:
tokens:
client_id: your_client_id
client_private: your_client_private
client_secret: your_client_secret
method: 'users.getInfo'
format: 'json'
secure: 1
Yandex:
tokens:
client_id: your_client_id
client_secret: your_client_secret
format: 'json'
SalesForce:
tokens:
client_id: your_client_id
client_secret: your_client_secret
[*] default value, may be omitted.
FUNCTIONAL LOGIN
The main purpose of this module is simply to authenticate against a
third party Identity Provider (IdP).
However you can get a bit more than that.
Your Dancer2 app might additionally use the "id_token" to access the
API of the same (or other) third parties to enable you to do cool stuff
with your apps, like show a feed, access data, etc.
Because access to the third party systems would be cut off when the
"id_token" expires, Dancer2::Plugin::Auth::OAuth will automatically set
up the route /auth/$provider/refresh. Call this when the token has
expired to try to refresh the token without bumping the user back to
log in. You can optionally tell Dancer2::Plugin::Auth::OAuth to bump
the user back to the login page if for whatever reason the refresh
fails.
In addition, Dancer2::Plugin::Auth::OAuth will save or generate an auth
session key called "expires", which is (usually) number of seconds from
epoch. Check this to determine if the "id_token" has expired (see
examples below).
Authenticate using one of the examples below but be sure to use the
'refresh' functionality, as the logged in user will need to have a
valid "id_token" at all times.
Also make sure that you set the scope of your authentication to tell
the third party what you wish to access (and for Microsoft/Azure also
set the resource, for the same reason).
Once you've got an active session you can get the "id_token" to use in
further calls to the providers backend systems with:
my $session_data = session->read('oauth');
my $token = $session_data->{$provider}{id_token};
SETTING THE SCOPE
If you're authenticating in order to use the "id_token" issued, or if
login requires a specific 'scope' setting, you can change these values
in the initial calls like this within your YAML config (example
provided for AzureAD plugin).
Auth::OAuth:
providers:
AzureAD:
query_params:
authorize:
scope: 'Calendars.ReadWrite Contacts.Read Directory.Read.All Files.Read.All Group.Read.All GroupMember.Read.All Mail.ReadWrite openid People.Read Sites.Read.All Sites.ReadWrite.All User.Read User.ReadBasic.All Files.Read.All'
You do not need to list all other authorize attributes sent to the
server, unless you want to change them from the default values set in
the provider. Please view the provider source/documentation for what
these default values are.
You may also need to set a value for "resource" in the same way. Refer
to your providers OAuth documentation.
AUTHENTICATION EXAMPLES
The response from the IdP is stored as a hash in the session with key
"oauth". An example of a Facebook response:
{
facebook {
access_token "...",
expires 1662472004,
expires_in 5183933,
issued_at 1657288071,
token_type "bearer",
user_info {
email "someone@example.com",
id 12345678901234567,
name "José do Telhado",
picture {
data {
height 50,
is_silhouette 0,
url "https://platform-lookaside.fbsbx.com/platform/profilepic/...",
width 50
}
},
}
}
}
Full site needs a user authentication for a specific IdP.
An example of a simple single system authentication.
hook before => sub {
my $session_data = session->read('oauth');
my $provider = "facebook"; # Lower case of the authentication plugin used
if ((!defined $session_data || !defined $session_data->{$provider} || !defined $session_data->{$provider}{id_token}) && request->path !~ m{^/auth}) {
return forward "/auth/$provider";
}
};
If you want to be sure they have a valid "id_token" at all times:
hook before => sub {
my $session_data = session->read('oauth');
my $provider = "facebook"; # Lower case of the authentication plugin used
my $now = DateTime->now->epoch;
if ((!defined $session_data || !defined $session_data->{$provider} || !defined $session_data->{$provider}{id_token}) && request->path !~ m{^/auth}) {
return forward '/auth/$provider';
} elsif (defined $session_data->{$provider}{refresh_token} && defined $session_data->{$provider}{expires} && $session_data->{$provider}{expires} < $now && request->path !~ m{^/auth}) {
return forward "/auth/$provider/refresh";
}
};
in the case where you're using the refresh functionality, a failure
of the refresh will send the user back to the "error_url". If you
want to them to instead be directed back to the main authentication
(log in page) then please set the configuration option
reauth_on_refresh_fail.
If the provider(s) you are using don't have the "id_token" change the
example accordingly.
Site has a mix of public zones and private or needing use
authentication
1. You only use one provider
get '/we/need/a/user/here' => sub {
my $session_data = session->read('oauth');
my $provider = "facebook";
redirect '/auth/$provider' unless $session_data && defined $session_data->{$provider};
...
}
2. You also have a login page to choose from a list of providers
accepted by the site
You may update the configuration file:
"Auth::OAuth":
success_url: /login/ok
error_url: /login/fail
And on your code
get '/we/need/a/user/here' => sub {
my $session_data = session->read('oauth');
redirect '/login' unless $session_data;
...
}
get '/login/ok' => sub {
my $session_data = session->read('oauth');
redirect '/login' unless $session_data;
# Do something with the user data, update DB,
# update session, etc
}
The login page can just have a list of the providers with a link to
"/auth/<lc-name-of-the-provider>"
You can mix this plugin with Dancer2::Plugin::Auth::Tiny and on
'/login/ok' you just define the 'user' session. Afterwards all
validation can be against 'user' and not 'oauth'.
AUTHOR
Menno Blom <blom@cpan.org>
COPYRIGHT
Copyright 2014- Menno Blom
LICENSE
This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.