medium url preview

Envfile

@@ -163,6 +163,10 @@ variable :TWITCH_WEBHOOK_SECRET, :String, default: "Optional"
 # (https://api.stackexchange.com/docs)
 variable :STACK_EXCHANGE_APP_KEY, :String, default: ""
 
+# For Heroku domain
+# ("https://medium.com/")
+variable :MEDIUM_DOMIAN, :String, default: "https://medium.com/"
+
 # For setting the IDs of the staff and welcoming users
 variable :STAFF_USER_ID, :Integer, default: 1
 variable :WELCOMING_USER_ID, :Integer, default: 1
@@ -182,4 +186,5 @@ group :production do
 
   # Heroku
   variable :HEROKU_APP_URL, :String  # practicaldev.herokuapp.com
+  variable :MEDIUM_DOMIAN, :String, default: "https://medium.com/"
 end

Gemfile

@@ -64,6 +64,7 @@ gem "oj", "~> 3.10" # JSON parser and object serializer
 gem "omniauth", "~> 1.9" # A generalized Rack framework for multiple-provider authentication
 gem "omniauth-github", "~> 1.3" # OmniAuth strategy for GitHub
 gem "omniauth-twitter", "~> 1.4" # OmniAuth strategy for Twitter
+gem "opengraph_parser", "~> 0.2.3" # Open Graph Protocol information from a website
 gem "pg", "~> 1.2" # Pg is the Ruby interface to the PostgreSQL RDBMS
 gem "puma", "~> 4.3" # Puma is a simple, fast, threaded, and highly concurrent HTTP 1.1 server
 gem "pundit", "~> 2.1" # Object oriented authorization for Rails applications

Gemfile.lock

@@ -512,6 +512,9 @@ GEM
     omniauth-twitter (1.4.0)
       omniauth-oauth (~> 1.1)
       rack
+    opengraph_parser (0.2.3)
+      addressable
+      nokogiri
     orm_adapter (0.5.0)
     os (1.0.1)
     parallel (1.19.1)
@@ -921,6 +924,7 @@ DEPENDENCIES
   omniauth (~> 1.9)
   omniauth-github (~> 1.3)
   omniauth-twitter (~> 1.4)
+  opengraph_parser (~> 0.2.3)
   parallel_tests (~> 2.31)
   pg (~> 1.2)
   pry (~> 0.12)

app/models/message.rb

@@ -118,6 +118,13 @@ def append_rich_links(html)
             #{user.name}
           </h1>
           </a>".html_safe
+      elsif (medium = rich_medium_link(anchor))
+        html += "<a href='#{medium.url}'
+        class='chatchannels__richlink'
+          target='_blank' data-content='sidecar-medium'>
+            #{"<div class='chatchannels__richlinkmainimage' style='background-image:url(" + medium.image_url + ")' data-content='sidecar-medium' ></div>" if medium.image_url.present?}
+          <h1 data-content='sidecar-medium'>#{medium.title}</h1>
+          <h4 data-content='sidecar-medium'>#{medium.description}</h4>".html_safe
       end
     end
     html
@@ -163,6 +170,14 @@ def rich_user_link(link)
     User.find_by(username: link["href"].split("/")[3].split("/")[0]) if link["href"].include?("//#{ApplicationConfig['APP_DOMAIN']}/")
   end
 
+  def rich_medium_link(link)
+    # restricted to preview only medium urls. Not sure we need to suport others or not.
+    return unless link["href"].include?(ApplicationConfig["MEDIUM_DOMIAN"]) && link["href"].split("/")[4]
+
+    website = OpenGraph.new(link["href"])
+    OpenStruct.new(title: website.title, url: website.url, description: website.description.presence, image_url: website.images.present? ? website.images.first : nil) if website
+  end
+
   def send_email_if_appropriate
     recipient = direct_receiver
     return if !chat_channel.direct? ||