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NAME

Facebook::OpenGraph - Simple way to handle Facebook's Graph API.

VERSION

This is Facebook::OpenGraph version 1.31

SYNOPSIS

use Facebook::OpenGraph;

# fetching public information about given objects
my $fb = Facebook::OpenGraph->new;
my $user = $fb->fetch('zuck');
my $page = $fb->fetch('oklahomer.docs');
my $objs = $fb->bulk_fetch([qw/zuck oklahomer.docs/]);

# get access_token for application
my $token_ref = Facebook::OpenGraph->new(+{
    app_id => 12345,
    secret => 'FooBarBuzz',
})->get_app_token;

# user authorization
my $fb = Facebook::OpenGraph->new(+{
    app_id       => 12345,
    secret       => 'FooBarBuzz',
    namespace    => 'my_app_namespace',
    redirect_uri => 'https://sample.com/auth_callback',
});
my $auth_url = $fb->auth_uri(+{
    scope => [qw/email publish_actions/],
});
$c->redirect($auth_url);

my $req = Plack::Request->new($env);
my $token_ref = $fb->get_user_token_by_code($req->query_param('code'));
$fb->set_access_token($token_ref->{access_token});

# publish photo
$fb->publish('/me/photos', +{
    source  => '/path/to/pic.png',
    message => 'Hello world!',
});

# publish Open Graph Action
$fb->publish_action($action_type, +{$object_type => $object_url});

DESCRIPTION

Facebook::OpenGraph is a Perl interface to handle Facebook's Graph API. This module is inspired by Facebook::Graph, but mainly focuses on simplicity and customizability because we must be able to keep up with frequently changing API specification.

This module does NOT provide ways to set and validate parameters for each API endpoint like Facebook::Graph does with Any::Moose. Instead it provides some basic methods for HTTP request. It also provides some handy methods that wrap request() for you to easily utilize most of Graph API's functionalities including:

  • API versioning that was introduced at f8, 2014.

  • Acquiring user, app and/or page token and refreshing user token for long lived one.

  • Batch Request

  • FQL

  • FQL with Multi-Query

  • Field Expansion

  • Etag

  • Wall Posting with Photo or Video

  • Creating Test Users

  • Checking and Updating Open Graph Object or Web Page with OGP

  • Publishing Open Graph Action

  • Deleting Open Graph Object

  • Posting Staging Resource for Open Graph Object

In most cases you can specify endpoints and request parameters by yourself and pass them to request() so it should be easier to test latest API specs. Other requesting methods merely wrap request() method for convinience.

METHODS

Class Methods

Facebook::OpenGraph->new(\%args)

Creates and returns a new Facebook::OpenGraph object.

%args can contain...

  • app_id

    Facebook application ID. app_id and secret are required to get application access token. Your app_id should be obtained from https://developers.facebook.com/apps/.

  • secret

    Facebook application secret. It should be obtained from https://developers.facebook.com/apps/.

  • version

    This declares Facebook Platform version. From 2014-04-30 they support versioning and migrations. Default value is undef because unversioned API access is also allowed. This value is prepended to the end point on request() unless you specify one in requesting path.

    my $fb = Facebook::OpenGraph->new(+{version => 'v2.0'});
    $fb->get('/zuck');      # Use version 2.0 by accessing /v2.0/zuck
    $fb->get('/v1.0/zuck'); # Ignore the default version and use version 1.0
    
    my $fb = Facebook::OpenGraph->new();
    $fb->get('/zuck'); # Unversioned API access since version is not specified
                       # on initialisation or reqeust.

    As of 2015-03-29, the latest version is v2.3. Detailed information should be found at https://developers.facebook.com/docs/apps/versions and https://developers.facebook.com/docs/apps/migrations.

  • ua

    This should be Furl::HTTP object or similar object that provides same interface. Default is equivalent to Furl::HTTP->new(capture_request => 1). You SHOULD install 2.10 or later version of Furl to enable capture_request option. Or you can specify keep_request option for same purpose if you have Furl 2.09. Setting capture_request option is strongly recommended since it gives you the request headers and content when request() fails.

    my $fb = Facebook::OpenGraph->new;
    $fb->post('/me/feed', +{message => 'Hello, world!'});
    #2500:- OAuthException:An active access token must be used to query information about the current user.
    #POST /me/feed HTTP/1.1
    #Connection: keep-alive
    #User-Agent: Furl::HTTP/2.15
    #Content-Type: application/x-www-form-urlencoded
    #Content-Length: 27
    #Host: graph.facebook.com
    #
    #message=Hello%2C%20world%21
  • namespace

    Facebook application namespace. This is used when you publish Open Graph Action via publish_action().

  • access_token

    Access token for user, application or Facebook Page.

  • redirect_uri

    The URL to be used for authorization. User will be redirected to this URL after login dialog. Detail should be found at https://developers.facebook.com/docs/reference/dialogs/oauth/.

    You must keep in mind that "The URL you specify must be a URL with the same base domain specified in your app's settings, a Canvas URL of the form https://apps.facebook.com/YOUR_APP_NAMESPACE or a Page Tab URL of the form https://www.facebook.com/PAGE_USERNAME/app_YOUR_APP_ID"

  • batch_limit

    The maximum number of queries that can be set within a single batch request. If the number of given queries exceeds this, then queries are divided into multiple batch requests, and responses are combined so it seems just like a single request.

    Default value is 50 as API documentation says. Official documentation is located at https://developers.facebook.com/docs/graph-api/making-multiple-requests/

    You must be aware that "each call within the batch is counted separately for the purposes of calculating API call limits and resource limits." See https://developers.facebook.com/docs/reference/ads-api/api-rate-limiting/.

  • is_beta

    Weather to use beta tier. See the official documentation for details. https://developers.facebook.com/support/beta-tier/.

  • json

    JSON object that handles request parameters and API response. Default is equivalent to JSON->new->utf8.

  • use_appsecret_proof

    Whether to use appsecret_proof parameter or not. Default is 0. Long-desired official document is now provided at https://developers.facebook.com/docs/graph-api/securing-requests/

    You must specify access_token and application secret to utilize this.

my $fb = Facebook::OpenGraph->new(+{
    app_id              => 123456,
    secret              => 'FooBarBuzz',
    ua                  => Furl::HTTP->new(capture_request => 1),
    namespace           => 'fb-app-namespace', # for Open Graph Action
    access_token        => '', # will be appended to request header in request()
    redirect_uri        => 'https://sample.com/auth_callback', # for OAuth
    batch_limit         => 50,
    json                => JSON->new->utf8,
    is_beta             => 0,
    use_appsecret_proof => 1,
    use_post_method     => 0,
    version             => undef,
})

Instance Methods

$fb->app_id

Accessor method that returns application id.

$fb->secret

Accessor method that returns application secret.

$fb->ua

Accessor method that returns Furl::HTTP object.

$fb->namespace

Accessor method that returns application namespace.

$fb->access_token

Accessor method that returns access token.

$fb->redirect_uri

Accessor method that returns URL that is used for user authorization.

$fb->batch_limit

Accessor method that returns the maximum number of queries that can be set within a single batch request. If the number of given queries exceeds this, then queries are divided into multiple batch requests, and responses are combined so it just seems like a single batch request. Default value is 50 as API documentation says.

$fb->is_beta

Accessor method that returns whether to use Beta tier or not.

$fb->json

Accessor method that returns JSON object. This object will be passed to Facebook::OpenGraph::Response via create_response().

$fb->use_appsecret_proof

Accessor method that returns whether to send appsecret_proof parameter on API call. Official document is not provided yet, but PHP SDK has this option and you can activate this option from App Setting > Advanced > Security.

$fb->use_post_method

Accessor method that returns whether to use POST method for every API call and alternatively set method=(GET|POST|DELETE) query parameter. PHP SDK works this way. This might work well when you use multi-query or some other functions that use GET method while query string can be very long and you have to worry about the maximum length of it.

$fb->version

Accessor method that returns Facebook Platform version. This can be undef unless you explicitly on initialisation.

$fb->uri($path, \%query_param)

Returns URI object with specified path and query parameter. If is_beta returns true, the base url is https://graph.beta.facebook.com/ . Otherwise its base url is https://graph.facebook.com/ . request() automatically determines if it should use uri() or video_uri() based on target path and parameters so you won't use uri() or video_uri() directly as long as you are using requesting methods that are provided in this module.

$fb->video_uri($path, \%query_param)

Returns URI object with specified path and query parameter. This should only be used when posting a video.

$fb->site_uri($path, \%query_param)

Returns URI object with specified path and query parameter. It is mainly used to generate URL for Auth dialog, but you can still use this when redirecting users to your Facebook page, App's Canvas page or any location on facebook.com.

my $fb = Facebook::OpenGraph->new(+{is_beta => 1});
$c->redirect($fb->site_uri($path_to_canvas));
# https://www.beta.facebook.com/$path_to_canvas

$fb->parse_signed_request($signed_request_str)

It parses signed_request that Facebook Platform gives to you on various situations. situations may include

  • Given as a URL fragment on callback endpoint after login flow is done with Login Dialog

  • POSTed when Page Tab App is loaded

  • Set in a form of cookie by JS SDK

Fields in returning value are introduced at https://developers.facebook.com/docs/reference/login/signed-request/.

my $req = Plack::Request->new($env);
my $val = $fb->parse_signed_request($req->query_param('signed_request'));

$fb->auth_uri(\%args)

Returns URL for Facebook OAuth dialog. You can redirect your user to this URL for authorization purpose.

If Facebook Platform version is set on initialisation, that value is prepended to the path. https://developers.facebook.com/docs/apps/versions#dialogs.

See the detailed flow at https://developers.facebook.com/docs/facebook-login/manually-build-a-login-flow. Optional values are shown at https://developers.facebook.com/docs/reference/dialogs/oauth/.

my $auth_url = $fb->auth_uri(+{
    display       => 'page', # Dialog's display type. Default value is 'page.'
    response_type => 'code',
    scope         => [qw/email publish_actions/],
});
$c->redirect($auth_url);

$fb->set_access_token($access_token)

Set $access_token as the access token to be used on request(). access_token() returns this value.

$fb->get_app_token

Obtain an access token for application. Give the returning value to set_access_token() and you can make request on behalf of your application. This access token never expires unless you reset application secret key on App Dashboard so you might want to store this value within your process like below...

package MyApp::OpenGraph;
use parent 'Facebook::OpenGraph';

sub get_app_token {
    my $self = shift;
    return $self->{__app_access_token__}
        ||= $self->SUPER::get_app_token->{access_token};
}

Or you might want to use Cache::Memory::Simple or something similar to refetch token at an interval of your choice. Maybe you want to store token on DB and override this method to return the stored value.

$fb->get_user_token_by_code($given_code)

Obtain an access token for user based on $code. $code should be obtained on your callback endpoint which is specified on eredirect_uri. Give the returning access token to set_access_token() and you can act on behalf of the user.

FYI: expires or expires_in is NOT returned on some edge cases. The detail and reproductive scenario should be found at https://developers.facebook.com/bugs/597779113651383/.

# On OAuth callback page which you specified on $fb->redirect_uri.
my $req          = Plack::Request->new($env);
my $token_ref    = $fb->get_user_token_by_code($req->query_param('code'));
my $access_token = $token_ref->{access_token};
my $expires      = $token_ref->{expires}; # named expires_in as of v2.3

$fb->get_user_token_by_cookie($cookie_value)

Obtain user access token based on the cookie value that is set by JS SDK. Cookie name should be determined with js_cookie_name().

FYI: expires or expires_in is NOT returned on some edge cases. The detail and reproductive schenario should be found at https://developers.facebook.com/bugs/597779113651383/.

if (my $cookie = $c->req->cookie( $fb->js_cookie_name )) {
  # User is not logged in yet, but cookie is set by JS SDK on previous visit.
  my $token_ref = $fb->get_user_token_by_cookie($cookie);
  # {
  #     "access_token" : "new_token_string_qwerty",
  #     "expires" : 5752 # named expires_in as of v2.3
  # };
}
else {
  return $c->redirect( $fb->auth_uri );
}

$fb->exchange_token($short_term_token)

Exchange short lived access token for long lived one. Short lived tokens are ones that you obtain with get_user_token_by_code(). Usually long lived tokens live about 60 days while short lived ones live about 2 hours.

FYI: expires or expires_in is NOT returned on some edge cases. The detail and reproductive schenario should be found at https://developers.facebook.com/bugs/597779113651383/.

my $extended_token_ref = $fb->exchange_token($token_ref->{access_token});
my $access_token       = $extended_token_ref->{access_token};
my $expires            = $extended_token_ref->{expires};
                         # named expires_in as of v2.3

If you loved the way old offline_access permission worked, and are looking for a substitute you might want to try this.

$fb->get($path, \%param, \@headers)

Alias to request() that sends GET request.

my $path = 'zuck'; # should be ID or username
my $user = $fb->get($path);
#{
#    name   => 'Mark Zuckerberg',
#    id     => 4,
#    locale => 'en_US',
#}

$fb->post($path, \%param, \@headers)

Alias to request() that sends POST request.

my $res = $fb->publish('/me/photos', +{source => '/path/to/pic.png'});
#{
#    id      => 123456,
#    post_id => '123456_987654',
#
#}

$fb->fetch($path, \%param, \@headers)

Alias to get() for those who got used to Facebook::Graph

$fb->publish($path, \%param, \@headers)

Alias to post() for those who got used to Facebook::Graph

$fb->fetch_with_etag($path, \%param, $etag_value)

Alias to request() that sends GET request with given ETag value. Returns undef if requesting data is not modified. Otherwise it returns modified data.

my $user = $fb->fetch_with_etag('/zuck', +{fields => 'email'}, $etag);

$fb->bulk_fetch(\@paths)

Request batch request and returns an array reference.

my $data = $fb->bulk_fetch([qw/zuck go.hagiwara/]);
#[
#    {
#        link => 'http://www.facebook.com/zuck',
#        name => 'Mark Zuckerberg',
#    },
#    {
#        link => 'http://www.facebook.com/go.hagiwara',
#        name => 'Go Hagiwara',
#    }
#]

$fb->batch(\@requests)

Request batch request and returns an array reference of response objects. It sets $fb->access_token as top level access token, but other than that you can specify indivisual access token for each request. The document says "The Batch API is flexible and allows individual requests to specify their own access tokens as a query string or form post parameter. In that case the top level access token is considered a fallback token and is used if an individual request has not explicitly specified an access token."

my $data = $fb->batch([
    +{method => 'GET', relative_url => 'zuck'},
    +{method => 'GET', relative_url => 'oklahomer.docs'},
]);

$fb->batch_fast(\@requests)

Request batch request and returns results as array reference, but it doesn't create Facebook::OpenGraph::Response to handle each response.

my $data = $fb->batch_fast([
    +{method => 'GET', relative_url => 'zuck'},
    +{method => 'GET', relative_url => 'oklahomer.docs'},
]);
#[
#    [
#        {
#            body    => {id => 4, name => 'Mark Zuckerberg', .....},
#            headers => [ .... ],
#            code    => 200,
#        },
#        {
#            body    => {id => 204277149587596, name => 'Oklahomer', .....},
#            headers => [ .... ],
#            code    => 200,
#        },
#    ]
#]

You can specify access token for each query within a single batch request. See https://developers.facebook.com/docs/graph-api/making-multiple-requests/ for detail.

$fb->fql($fql_query)

Alias to request() that optimizes query parameter for FQL query and sends GET request.

my $res = $fb->fql('SELECT display_name FROM application WHERE app_id = 12345');
#{
#    data => [{
#        display_name => 'app',
#    }],
#}

$fb->bulk_fql(\%fql_queries)

Alias to fql() to request multiple FQL query at once.

my $res = $fb->bulk_fql(+{
    'all friends' => 'SELECT uid2 FROM friend WHERE uid1 = me()',
    'my name'     => 'SELECT name FROM user WHERE uid = me()',
});
#{
#    data => [
#        {
#            fql_result_set => [
#                {uid2 => 12345},
#                {uid2 => 67890},
#            ],
#            name => 'all friends',
#        },
#        {
#            fql_result_set => [
#                name => 'Michael Corleone'
#            ],
#            name => 'my name',
#        },
#    ],
#}

$fb->delete($path, \%param)

Alias to request() that sends DELETE request to delete object on Facebook's social graph. It sends POST request with method=delete query parameter when DELETE request fails. I know it's weird, but sometimes DELETE fails and POST with method=delete works.

$fb->delete($object_id);

$fb->request($request_method, $path, \%param, \@headers)

Sends request to Facebook Platform and returns Facebook::Graph::Response object.

$fb->gen_appsecret_proof

Generates signature for appsecret_proof parameter. This method is called in request() if $self-use_appsecret_proof> is set. See http://facebook-docs.oklahome.net/archives/52097348.html for Japanese Info.

Generates and returns the name of cookie that is set by JS SDK on client side login. This value can be parsed as signed request and the parsed data structure contains 'code' to exchange for acess token. See get_user_token_by_cookie() for detail.

$fb->create_response($http_status_code, $http_status_message, \@response_headers, $response_content)

Creates and returns Facebook::OpenGraph::Response. If you wish to use customized response class, then override this method to return MyApp::Better::Response.

$fb->prep_param(\%param)

Handles sending parameters and format them in the way Graph API spec states. This method is called in request() so you don't usually use this method directly.

$fb->prep_fields_recursive(\@fields)

Handles fields parameter and format it in the way Graph API spec states. The main purpose of this method is to deal with Field Expansion (https://developers.facebook.com/docs/graph-api/using-graph-api/#fieldexpansion). This method is called in prep_param which is called in request() so you don't usually use this method directly.

# simple fields
$fb->prep_fields_recursive([qw/name email albums/]); # name,email,albums

# use field expansion
$fb->prep_fields_recursive([
    'name',
    'email',
    +{
        albums => +{
            fields => [
                'name',
                +{
                    photos => +{
                        fields => [
                            'name',
                            'picture',
                            +{
                                tags => +{
                                    limit => 2,
                                },
                            }
                        ],
                        limit => 3,
                    }
                }
            ],
            limit => 5,
        }
    }
]);
# 'name,email,albums.fields(name,photos.fields(name,picture,tags.limit(2)).limit(3)).limit(5)'

$fb->publish_action($action_type, \%param)

Alias to request() that optimizes body content and endpoint to send POST request to publish Open Graph Action.

my $res = $fb->publish_action('give', +{crap => 'https://sample.com/poop/'});
#{id => 123456}

$fb->create_test_users(\@settings)

my $res = $fb->create_test_users([
    +{
        permissions => [qw/publish_actions/],
        locale      => 'en_US',
        installed   => 'true',
    },
    +{
        permissions => [qw/publish_actions email read_stream/],
        locale      => 'ja_JP',
        installed   => 'true',
    }
])
#[
#    +{
#        id           => 123456789,
#        access_token => '5678uiop',
#        login_url    => 'https://www.facebook.com/........',
#        email        => '.....@tfbnw.net',
#        password     => '.......',
#    },
#    +{
#        id           => 1234567890,
#        access_token => '5678uiopasadfasdfa',
#        login_url    => 'https://www.facebook.com/........',
#        email        => '.....@tfbnw.net',
#        password     => '.......',
#    },
#];

Alias to request() that optimizes to create test users for your application.

$fb->publish_staging_resource($file_path)

Alias to request() that optimizes body content to send POST request to upload image to Object API's staging environment.

my $fb = Facebook::OpenGraph->new(+{
    access_token => $USER_ACCESS_TOKEN,
});
my $res = $fb->publish_staging_resource('/path/to/file');
#{
#  uri => 'fbstaging://graph.facebook.com/staging_resources/MDExMzc3MDU0MDg1ODQ3OTY2OjE5MDU4NTM1MzQ=',
#};

$fb->check_object($object_id_or_url)

Alias to request() that sends POST request to Facebook Debugger to check/update object.

$fb->check_object('https://sample.com/object/');
$fb->check_object($object_id);

AUTHOR

Oklahomer <hagiwara dot go at gmail dot com>

SUPPORT

SEE ALSO

Facebook::Graph

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.