Common Open Graph meta tag and Facebook Social Plugin tag helpers.
There are only small subsets of tags are supported (for now).
Pull requests are welcome.
The Facebook Social Plugins can be rendered in HTML5 version (default) or <iframe> version. Their default options are tuned for Techbang. Override them by passing a Hash; see below.
Add this to your Gemfile:
gem 'open_graph_helper'
If you want to use the edge version on Github, specify the :git option.
gem 'open_graph_helper', github: 'techbang/open_graph_helper'
And run
bundle install
to install this plug-in.
For Social Plugins, OpenGraphHelper provides 2 versions for that: the new :html5 and legacy :iframe.
:html5 version is the default option and requires JavaScript SDK. See Facebook JavaScript SDK for more details. If you're using Facebooker2, please include the SDK by <%= fb_connect_async_js %>.
To switch to :iframe version, you need an initializer. Name it, say, open_graph_helper.rb, with one line of content:
OpenGraphHelper::SOCIAL_PLUGIN_VERSION = :iframe # HTML5 + JS SDK doesn't need thisThe last thing: don't forget to add XML namespaces to the <html> tag, or <meta> tags won't work.
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:og="http://ogp.me/ns#"
xmlns:fb="http://www.facebook.com/2008/fbml">Examples: (Sample output from Facebook Open Graph Documentation)
og_title("The Rock")
#=> <meta property="og:title" content="The Rock"/>
og_type("movie") # default is "article"
#=> <meta property="og:type" content="movie"/>
og_url("http://www.imdb.com/title/tt0117500/")
#=> <meta property="og:url" content="http://www.imdb.com/title/tt0117500/"/>
og_image("http://ia.media-imdb.com/rock.jpg")
#=> <meta property="og:image" content="http://ia.media-imdb.com/rock.jpg"/>
og_site_name("IMDb")
#=> <meta property="og:site_name" content="IMDb"/>
og_description("Lorem Ipsum ...")
#=> <meta property="og:description" cotent="Lorem Ipsum ..."/>
og_fb_admins(%w(123456 789012)) # Accepts an Array for multiple admins
#=> <meta property="fb:admins" content="123456"/>
# <meta property="fb:admins" content="789012"/>
og_fb_app_id("1234567890")
#=> <meta property="fb:app_id" content="1234567890"/>According to Open Graph Protocol, multiple-value should be represented as an Array, not separated by a single comma , (U+002C).
This pitfall was found when assigning admins for Facebook Comments Plug-In. Although the document says:
To add multiple moderators, separate the uids by comma without spaces.
It does actually not working, and a parser error will be warned by Open Graph Debugger. A working example should like this:
<meta property="fb:admins" content="123456">
<meta property="fb:admins" content="789012">Therefore, OpenGraphHelper's og_fb_admins accepts an array, in which situation it maps each element to a single fb:admins meta tag, and concatenates them in a single line.
See this QA: http://stackoverflow.com/a/12007788
There are some default options that was optimized for Techbang sites and may not suits for your needs. Override them by passing a Hash as the last argument.
Usage: fb_like(like_url, options={})
The default options are:
layout: "button_count",
action: "like",
share: false,
show_faces: false,
width: 90
For more options, see Facebook Like Button Documentation
Example:
fb_like("http://example.com")
#=> <div class="fb-like" data-href="http://example.com" data-layout="button_count" data-action="like" data-share="false" data-show-faces="false" data-width="90"></div>
fb_like("http://example.com", width: 120, layout: "standard")
#=> <div class="fb-like" data-href="http://example.com" data-layout="standard" data-action="like" data-share="false" data-show-faces="false" data-width="120"></div>Usage: fb_page(fans_page_url, options={})
The default options are:
small_header: true,
adapt_container_width: true,
hide_cover: false,
show_facepile: false
For more options, see Facebook Page Plugin Documentation
Example:
fb_page("https://www.facebook.com/facebook")
#=> <div class="fb-page" data-href="https://www.facebook.com/facebook" data-small-header="true", data-adapt-container-width="true" data-hide-cover="false" data-show-facepile="false"><blockquote cite="https://www.facebook.com/facebook" class="fb-xfbml-parse-ignore"><a href="https://www.facebook.com/facebook">Facebook</a></blockquote></div>
fb_page("https://www.facebook.com/facebook", small_header: false, width: 200, tabs: "timeline", adapt_container_width: false)
#=> <div class="fb-page" data-href="https://www.facebook.com/facebook" data-small-header="false" data-width="200" data-tabs="timeline" data-adapt-container-width="false" data-hide-cover="false" data-show-facepile="false"><blockquote cite="https://www.facebook.com/facebook" class="fb-xfbml-parse-ignore"><a href="https://www.facebook.com/facebook">Facebook</a></blockquote></div>This software is released under the MIT License
Copyright (c) 2011- Techbang
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