Merge remote-tracking branch 'origin/master' into gs-master

  Conflicts:
 	.travis.yml
 	Gemfile.lock
 	README.md
 	app/controllers/settings/follower_domains_controller.rb
 	app/controllers/statuses_controller.rb
 	app/javascript/mastodon/locales/ja.json
 	app/lib/feed_manager.rb
 	app/models/media_attachment.rb
 	app/models/mute.rb
 	app/models/status.rb
 	app/services/mute_service.rb
 	app/views/home/index.html.haml
 	app/views/stream_entries/_simple_status.html.haml
 	config/locales/ca.yml
 	config/locales/en.yml
 	config/locales/es.yml
 	config/locales/fr.yml
 	config/locales/nl.yml
 	config/locales/pl.yml
 	config/locales/pt-BR.yml
 	config/themes.yml

1 files changed, 71 insertions, 0 deletions

diff --git a/app/services/fetch_oembed_service.rb b/app/services/fetch_oembed_service.rb
new file mode 100644
index 000000000..998228517
--- /dev/null
+++ b/app/services/fetch_oembed_service.rb
@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+class FetchOEmbedService
+  attr_reader :url, :options, :format, :endpoint_url
+
+  def call(url, options = {})
+    @url     = url
+    @options = options
+
+    discover_endpoint!
+    fetch!
+  end
+
+  private
+
+  def discover_endpoint!
+    return if html.nil?
+
+    @format = @options[:format]
+    page    = Nokogiri::HTML(html)
+
+    if @format.nil? || @format == :json
+      @endpoint_url ||= page.at_xpath('//link[@type="application/json+oembed"]')&.attribute('href')&.value
+      @format       ||= :json if @endpoint_url
+    end
+
+    if @format.nil? || @format == :xml
+      @endpoint_url ||= page.at_xpath('//link[@type="text/xml+oembed"]')&.attribute('href')&.value
+      @format       ||= :xml if @endpoint_url
+    end
+
+    return if @endpoint_url.blank?
+
+    @endpoint_url = Addressable::URI.parse(@endpoint_url).to_s
+  rescue Addressable::URI::InvalidURIError
+    @endpoint_url = nil
+  end
+
+  def fetch!
+    return if @endpoint_url.blank?
+
+    body = Request.new(:get, @endpoint_url).perform do |res|
+      res.code != 200 ? nil : res.body_with_limit
+    end
+
+    validate(parse_for_format(body)) unless body.nil?
+  rescue Oj::ParseError, Ox::ParseError
+    nil
+  end
+
+  def parse_for_format(body)
+    case @format
+    when :json
+      Oj.load(body, mode: :strict)&.with_indifferent_access
+    when :xml
+      Ox.load(body, mode: :hash_no_attrs)&.with_indifferent_access&.dig(:oembed)
+    end
+  end
+
+  def validate(oembed)
+    oembed if oembed[:version] == '1.0' && oembed[:type].present?
+  end
+
+  def html
+    return @html if defined?(@html)
+
+    @html = @options[:html] || Request.new(:get, @url).perform do |res|
+      res.code != 200 || res.mime_type != 'text/html' ? nil : res.body_with_limit
+    end
+  end
+end