Preview medium

Envfile

@@ -33,6 +33,9 @@ variable :REDIS_SIDEKIQ_URL, :String, default: "redis://localhost:6379"
 # Elasticsearch
 variable :ELASTICSEARCH_URL, :String, default: "http://localhost:9200"
 
+# env
+variable :MEDIUM_DOMIAN, :String, default: "https://medium.com/"
+
 ################################################
 ############## 3rd Party Services ##############
 ################################################
@@ -182,4 +185,5 @@ 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"
 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
   parallel_tests (~> 2.31)
   pg (~> 1.2)
   pry (~> 0.12)

app/models/message.rb

@@ -118,8 +118,11 @@ def append_rich_links(html)
             #{user.name}
           </h1>
           </a>".html_safe
+      elsif (medium = PreviewMediumService.call(anchor))
+        html += medium.rich_link.html_safe
       end
     end
+
     html
   end
 

app/services/preview_medium_service.rb

@@ -0,0 +1,51 @@
+class PreviewMediumService
+  def initialize(link)
+    @href = link["href"]
+  end
+
+  def self.call(link)
+    new(link).call
+  end
+
+  def call
+    return unless valid_url?
+
+    response = send_request
+    return unless response
+
+    @medium = create_attributes(response)
+    self
+  end
+
+  def rich_link
+    return "" unless valid_url?
+
+    "<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>"
+  end
+
+  private
+
+  attr_reader :href, :medium
+
+  def valid_url?
+    href.include?(ApplicationConfig["MEDIUM_DOMIAN"]) && href.split("/")[4].present?
+  end
+
+  def send_request
+    OpenGraph.new(href)
+  end
+
+  def create_attributes(response)
+    OpenStruct.new(
+      url: response.url,
+      image_url: response.images[0],
+      title: response.title,
+      description: response.description,
+    )
+  end
+end

spec/models/message_spec.rb

@@ -7,6 +7,7 @@
   let(:chat_channel) { create(:chat_channel) }
   let(:message) { create(:message, user: user) }
   let(:random_word) { Faker::Lorem.word }
+  let(:medium_url) { "https://medium.com/@jpsmithalt/hold-the-line-17231c48ff17" }
 
   describe "validations" do
     context "with automatic validations" do
@@ -73,6 +74,23 @@
         expect(message.message_html).not_to include("data-content")
       end
 
+      it "creates rich link with non-rich link for medium" do
+        stub_request(:get, medium_url).
+          with(
+            headers: {
+              "Accept" => "*/*",
+              "Accept-Encoding" => "gzip;q=1.0,deflate;q=0.6,identity;q=0.3",
+              "User-Agent" => "Ruby"
+            },
+          ).
+          to_return(status: 200, body: "medium article", headers: {})
+
+        message.message_markdown = medium_url
+        message.validate!
+
+        expect(message.message_html).to include("data-content")
+      end
+
       it "creates mention if user exists" do
         message.message_markdown = "Hello @#{user.username}"
         message.validate!

spec/services/preview_medium_spec_service_spec.rb

@@ -0,0 +1,82 @@
+require "rails_helper"
+
+RSpec.describe PreviewMediumService, type: :service do
+  describe "service methods" do
+    let(:valid_medium_url) { "https://medium.com/@sfchronicle/why-mark-zuckerberg-should-step-down-as-facebook-ceo-795410ef12eb" }
+    let(:invalid_medium_url) { "https://dev.to/nas5w/first-class-functions-in-javascript-5dj2" }
+    let(:object) { described_class.call("href" => valid_medium_url) }
+
+    before do
+      stub_request(:get, valid_medium_url).
+        with(
+          headers: {
+            "Accept" => "*/*",
+            "Accept-Encoding" => "gzip;q=1.0,deflate;q=0.6,identity;q=0.3",
+            "User-Agent" => "Ruby"
+          },
+        ).
+        to_return(status: 200, body: "medium", headers: {})
+    end
+
+    describe "class_methods" do
+      it ".call" do
+        expect(object).to be_a described_class
+      end
+    end
+
+    describe "instance_methods" do
+      context "with #call" do
+        it "return nil without valid_url" do
+          allow(object).to receive(:valid_url?).and_return(false)
+          expect(object.call).to be_nil
+        end
+
+        it "return nil with invalid response" do
+          allow(object).to receive(:send_request).and_return(nil)
+          expect(object.call).to be_nil
+        end
+
+        it "return object with sucess response" do
+          expect(object.call).to be_a described_class
+        end
+      end
+
+      context "with #valid_url" do
+        it "with valid url" do
+          expect(object.send(:valid_url?)).to be_truthy
+        end
+
+        it "with invalid url" do
+          allow(object).to receive(:href).and_return(invalid_medium_url)
+          expect(object.send(:valid_url?)).to be_falsy
+        end
+      end
+
+      context "with #rich_link" do
+        it "return with invalid_url" do
+          allow(object).to receive(:valid_url?).and_return(false)
+          expect(object.rich_link).to eq("")
+        end
+
+        it "return with valid_url" do
+          expect(object.rich_link).to include("sidecar-medium")
+          expect(object.rich_link).to include("chatchannels__richlink")
+        end
+      end
+
+      it "#create_attributes" do
+        response = OpenStruct.new(
+          url: valid_medium_url,
+          images: ["https://miro.medium.com/max/920/0*x6DKkfEFloE-Lgiw.jpg"],
+          title: "Why Mark Zuckerberg Should Step Down as Facebook CEO",
+          description: "A shift in the role of CEO Mark Zuckerberg might help address",
+        )
+        res = object.send(:create_attributes, response)
+        expect(res.url).to eq(response.url)
+        expect(res.image_url).to eq(response.images[0])
+        expect(res.title).to eq(response.title)
+        expect(res.description).to eq(response.description)
+      end
+    end
+  end
+end