From 0930e5fa23db0e8d065b5a44514c3396009a50b4 Mon Sep 17 00:00:00 2001
From: Marcin Kulik <m@ku1ik.com>
Date: Sun, 29 Mar 2015 18:19:18 +0000
Subject: [PATCH] Add oEmbed endpoint

---
 app/controllers/application_controller.rb |  6 +-
 app/controllers/oembed_controller.rb      | 70 +++++++++++++++++++++++
 app/uploaders/asciicast_uploader.rb       |  6 +-
 app/views/oembed/show.html.erb            |  1 +
 config/routes.rb                          |  2 +
 spec/api/oembed_spec.rb                   | 17 ++++++
 6 files changed, 97 insertions(+), 5 deletions(-)
 create mode 100644 app/controllers/oembed_controller.rb
 create mode 100644 app/views/oembed/show.html.erb
 create mode 100644 spec/api/oembed_spec.rb

diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 4dc284f..d68f30e 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -81,6 +81,10 @@ class ApplicationController < ActionController::Base
     end
   end
 
-  helper_method :profile_path
+  def profile_url(user)
+    root_url[0..-2] + profile_path(user)
+  end
+
+  helper_method :profile_path, :profile_url
 
 end
diff --git a/app/controllers/oembed_controller.rb b/app/controllers/oembed_controller.rb
new file mode 100644
index 0000000..1ef185c
--- /dev/null
+++ b/app/controllers/oembed_controller.rb
@@ -0,0 +1,70 @@
+class OembedController < ApplicationController
+
+  def show
+    url = URI.parse(params[:url])
+
+    if url.path =~ %r{^/a/(\d+)$}
+      id = $1
+      asciicast = AsciicastDecorator.new(Asciicast.find(id))
+      oembed = oembed_response(asciicast)
+
+      respond_to do |format|
+        format.json do
+          render json: oembed
+        end
+        format.xml do
+          render xml: oembed.to_xml(root: 'oembed')
+        end
+      end
+    else
+      head :bad_request
+    end
+  end
+
+  private
+
+  def oembed_response(asciicast)
+    width, height = asciicast.image_width, asciicast.image_height
+
+    if params[:maxwidth]
+      width, height = size_smaller_than(width, height, params[:maxwidth], params[:maxheight])
+    end
+
+    oembed = {
+      type: 'rich',
+      version: 1.0,
+      title: asciicast.title,
+      author_name: asciicast.user.display_name,
+      author_url: profile_url(asciicast.user),
+      provider_name: 'asciinema',
+      provider_url: root_url,
+      thumbnail_url: asciicast.image_url,
+      thumbnail_width: width,
+      thumbnail_height: height,
+      html: render_html(asciicast, width),
+      width: width,
+      height: height,
+    }
+  end
+
+  def render_html(asciicast, width)
+    render_to_string(
+      template: 'oembed/show.html.erb',
+      layout: false,
+      locals: { asciicast: asciicast, width: width }
+    ).chomp
+  end
+
+  def size_smaller_than(width, height, max_width, max_height)
+    fw = Rational(max_width, width)
+    fh = Rational(max_height, height)
+
+    if fw > 1 && fh > 1
+      [width, height]
+    else
+      f = [fw, fh].min
+      [(Rational(width) * f).to_i, (Rational(height) * f).to_i]
+    end
+  end
+
+end
diff --git a/app/uploaders/asciicast_uploader.rb b/app/uploaders/asciicast_uploader.rb
index 07cae1b..2670736 100644
--- a/app/uploaders/asciicast_uploader.rb
+++ b/app/uploaders/asciicast_uploader.rb
@@ -1,12 +1,10 @@
 class AsciicastUploader < BaseUploader
 
   def url
-    url = super
-
-    if url[0] == '/'
+    if CFG.carrierwave_storage == 'file'
       path
     else
-      url
+      super
     end
   end
 
diff --git a/app/views/oembed/show.html.erb b/app/views/oembed/show.html.erb
new file mode 100644
index 0000000..2357cb8
--- /dev/null
+++ b/app/views/oembed/show.html.erb
@@ -0,0 +1 @@
+<%= link_to image_tag(asciicast.image_url, width: width, alt: asciicast.title), asciicast_url(asciicast), target: '_blank' %>
diff --git a/config/routes.rb b/config/routes.rb
index ab71d24..faa3066 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -15,6 +15,8 @@ Rails.application.routes.draw do
   get "/u/:id" => "users#show", as: :unnamed_user
   get "/~:username" => "users#show", as: :public_profile
 
+  get "/oembed" => "oembed#show", as: :oembed
+
   namespace :api do
     resources :asciicasts
   end
diff --git a/spec/api/oembed_spec.rb b/spec/api/oembed_spec.rb
new file mode 100644
index 0000000..fcf52e7
--- /dev/null
+++ b/spec/api/oembed_spec.rb
@@ -0,0 +1,17 @@
+require 'rails_helper'
+
+describe "oEmbed provider" do
+
+  let(:asciicast) { create(:asciicast) }
+
+  it "responds with status 200 for JSON" do
+    get "/oembed?url=http://localhost:3000/a/#{asciicast.id}&format=json"
+    expect(response.status).to eq(200)
+  end
+
+  it "responds with status 200 for XML" do
+    get "/oembed?url=http://localhost:3000/a/#{asciicast.id}&format=xml"
+    expect(response.status).to eq(200)
+  end
+
+end