Net::OAuth2::Profile::WebServer(3)

NAME
Net::OAuth2::Profile::WebServer - OAuth2 for web-server use

INHERITANCE
 Net::OAuth2::Profile::WebServer
   is a Net::OAuth2::Profile

SYNOPSIS
  # See examples/psgi/
  my $auth = Net::OAuth2::Profile::WebServer->new
    ( name           => 'Google Contacts'
    , client_id      => $id
    , client_secret  => $secret
    , site           => 'https://accounts.google.com'
    , scope          => 'https://www.google.com/m8/feeds/'
    , authorize_path    => '/o/oauth2/auth'
    , access_token_path => '/o/oauth2/token'
    , protected_resource_url
        =>  'https://www.google.com/m8/feeds/contacts/default/full'
    );

  # Let user ask for a grant from the resource owner
  print $auth->authorize_response->as_string;
  # or, in Plack:   redirect $auth->authorize;

  # Prove your identity at the authorization server
  # The $info are the parameters from the callback to your service, it
  # will contain a 'code' value.
  my $access_token  = $auth->get_access_token($info->{code});

  # communicate with the resource serve
  my $response      = $access_token->get('/me');
  $response->is_success
      or die "error: " . $response->status_line;

  print "Yay, it worked: " . $response->decoded_content;

DESCRIPTION
Use OAuth2 in a WebServer context. Read the DETAILS section, far below this man-page before you start implementing this interface.

Extends "DESCRIPTION" in Net::OAuth2::Profile.

METHODS
Extends "METHODS" in Net::OAuth2::Profile.

  Constructors
Extends "Constructors" in Net::OAuth2::Profile.

Net::OAuth2::Profile::WebServer->new(%options)
     -Option           --Defined in          --Default
      auto_save                                <set token's changed flag>
      client_id          Net::OAuth2::Profile  <required>
      client_secret      Net::OAuth2::Profile  <required>
      grant_type         Net::OAuth2::Profile  'authorization_code'
      hd                 Net::OAuth2::Profile  undef
      redirect_uri                             undef
      referer                                  undef
      scope              Net::OAuth2::Profile  undef
      secrets_in_params  Net::OAuth2::Profile  <true>
      site               Net::OAuth2::Profile  undef
      state              Net::OAuth2::Profile  undef
      token_scheme       Net::OAuth2::Profile  'auth-header:Bearer'
      user_agent         Net::OAuth2::Profile  <created internally>

    auto_save => CODE
        When a new token is received or refreshed, it usually needs to get save into a database or file. The moment you receive a new token is clear, but being aware of refreshes in your main program is a hassle. Read more about configuring this in the "DETAILS" section below.

    client_id => STRING
    client_secret => STRING
    grant_type => STRING
    hd => STRING
    redirect_uri => URI
    referer => URI
        Adds a "Referer" header to each request. Some servers check whether provided redirection uris point to the same server the page where the link was found.

    scope => STRING
    secrets_in_params => BOOLEAN
    site => URI
    state => STRING
    token_scheme => SCHEME
    user_agent => LWP::UserAgent object

  Accessors
Extends "Accessors" in Net::OAuth2::Profile.

$obj->auto_save()
$obj->bearer_token_scheme()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->grant_type()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->hd()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->id()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->redirect_uri()
$obj->referer( [$uri] )
$obj->scope()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->secret()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->site()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->state()
    Inherited, see "Accessors" in Net::OAuth2::Profile

$obj->user_agent()
    Inherited, see "Accessors" in Net::OAuth2::Profile

  Actions
Extends "Actions" in Net::OAuth2::Profile.

$obj->authorize(%options)
    On initial contact of a new user, you have to redirect to the resource owner. Somewhere in the near future, your application will be contacted again by the same user but then with an authorization grant code.

    Only the most common %options are listed... there may be more: read the docs on what your server expects.

     -Option       --Default
      client_id      new(client_id)
      response_type  'code'
      scope          undef
      state          undef

    client_id => STRING
    response_type => STRING
    scope => STRING
    state => STRING

    example:

      my $auth = Net::OAuth2::Profile::WebServer->new(...);

      # From the Plack demo, included in this distribution (on CPAN)
      get '/get' => sub { redirect $auth->authorize };

      # In generic HTTP, see method authorize_response
      use HTTP::Status 'HTTP_TEMPORARY_REDIRECT';   # 307
      print HTTP::Response->new
        ( HTTP_TEMPORARY_REDIRECT => 'Get authorization grant'
        , [ Location => $auth->authorize ]
        )->as_string;

$obj->authorize_response( [$request] )
    Convenience wrapper around authorize(), to produce a complete HTTP::Response object to be sent back.

$obj->get_access_token(CODE, %options)
     -Option       --Default
      client_id      new(client_id)
      client_secret  new(client_secret)

    client_id => STRING
    client_secret => STRING

$obj->update_access_token($token, %options)
    Ask the server for a new token. You may pass additional %options as pairs. However, this method is often triggered automatically, in which case you can to use the "refresh_token_params" option of new().

    example:

      $auth->update_access_token($token);
      $token->refresh;   # nicer

  Helpers
Extends "Helpers" in Net::OAuth2::Profile.

$obj->add_token($request, $token, $scheme)
    Inherited, see "Helpers" in Net::OAuth2::Profile

$obj->build_request($method, $uri, $params)
    Inherited, see "Helpers" in Net::OAuth2::Profile

$obj->params_from_response($response, $reason)
    Inherited, see "Helpers" in Net::OAuth2::Profile

$obj->site_url( <$uri|$path>, $params )
    Inherited, see "Helpers" in Net::OAuth2::Profile

DETAILS
OAuth2 is a server-server protocol, not the usual client-server set-up. The consequence is that the protocol handlers on both sides will not wait for another during the communication: the remote uses callback urls to pass on the response. Your side of the communication, your webservice, needs to re-group these separate processing steps into logical sessions.

  The process
The client side of the process has three steps, nicely described in <https://tools.ietf.org/html/rfc6749|RFC6749>

1. Send an authorization request to resource owner
    It needs a "client_id": usually the name of the service where you want get access to. The answer is a redirect, based on the "redirection_uri" which you usually pass on. Additional "scope", "state", and "hd" parameters can be needed or useful. The redirect will provide you with (amongst other things) a "code" parameter.

2. Translate the code into an access token
    With the code, you go to an authorization server which will validate your existence. An access token (and sometimes a refresh token) are returned.

3. Address the protected resource
    The access token, usually a 'bearer' token, is added to each request to the resource you want to address. The token may refresh itself when needed.

  Saving the token
Your application must implement a persistent session, probably in a database or file. The session information is kept in an Net::OAuth2::AccessToken object, and does contain more facts than just the access token.

Let's discuss the three approaches.

no saving

The Plack example contained in the CPAN distribution of this module is a single process server. The tokens are administered in the memory of the process. It is nice to test your settings, but probably not realistic for any real-life application.

automatic saving

When your own code is imperative:

  my $auth = Net::OAuth2::Profile::WebServer->new
    ( ...
    , auto_save => \&save_session
    );

  sub save_session($$)
  {   my ($profile, $token) = @_;
      ...
  }

When your own code is object oriented:

  sub init(...)
  {  my ($self, ...) = @_;
     my $auth = Net::OAuth2::Profile::WebServer->new
       ( ...
       , auto_save => sub { $self->save_session(@_) }
       );
  }

  sub save_session($$)
  {   my ($self, $profile, $token) = @_;
      ...
  }

explicit saving

In this case, do not use new(auto_save).

COPYRIGHTS
Copyrights 2013-2019 on the perl code and the related documentation
 by [Mark Overmeer <markov@cpan.org>] for SURFnet bv, The Netherlands. For other contributors see "Changes".

Copyrights 2011-2012 by Keith Grennan.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See http://dev.perl.org/licenses/