Fix #54 - Fetch remote accounts by URL from mentions

Fetching atom extracted from FetchRemoteAccountService and FetchRemoteStatusService
into FetchAtomService. Mentions of the constant "http://activityschema.org/collection/public"
skipped as it's not a real URL/user.

app/services/fan_out_on_write_service.rb

@@ -23,7 +23,7 @@ class FanOutOnWriteService < BaseService
   def deliver_to_mentioned(status)
     status.mentions.each do |mention|
       mentioned_account = mention.account
-      next unless mentioned_account.local?
+      next if !mentioned_account.local? || mentioned_account.id == status.account_id
       FeedManager.instance.push(:mentions, mentioned_account, status)
     end
   end

app/services/fetch_atom_service.rb

@@ -0,0 +1,46 @@
+class FetchAtomService < BaseService
+  def call(url)
+    response = http_client.head(url)
+
+    Rails.logger.debug "Remote status HEAD request returned code #{response.code}"
+    return nil if response.code != 200
+
+    if response.mime_type == 'application/atom+xml'
+      return [url, fetch(url)]
+    elsif !response['Link'].blank?
+      return process_headers(response)
+    else
+      return process_html(fetch(url))
+    end
+  end
+
+  private
+
+  def process_html(body)
+    Rails.logger.debug "Processing HTML"
+
+    page = Nokogiri::HTML(body)
+    alternate_link = page.xpath('//link[@rel="alternate"]').find { |link| link['type'] == 'application/atom+xml' }
+
+    return nil if alternate_link.nil?
+    return [alternate_link['href'], fetch(alternate_link['href'])]
+  end
+
+  def process_headers(response)
+    Rails.logger.debug "Processing link header"
+
+    link_header    = LinkHeader.parse(response['Link'])
+    alternate_link = link_header.find_link(['rel', 'alternate'], ['type', 'application/atom+xml'])
+
+    return nil if alternate_link.nil?
+    return [alternate_link.href, fetch(alternate_link.href)]
+  end
+
+  def fetch(url)
+    http_client.get(url).to_s
+  end
+
+  def http_client
+    HTTP.timeout(:per_operation, write: 20, connect: 20, read: 50)
+  end
+end

app/services/fetch_feed_service.rb

@@ -1,17 +0,0 @@
-class FetchFeedService < BaseService
-  # Fetch an account's feed and process it
-  # @param [Account] account
-  def call(account)
-    process_service.(http_client.get(account.remote_url), account)
-  end
-
-  private
-
-  def process_service
-    @process_service ||= ProcessFeedService.new
-  end
-
-  def http_client
-    HTTP
-  end
-end

app/services/fetch_remote_account_service.rb

@@ -0,0 +1,22 @@
+class FetchRemoteAccountService < BaseService
+  def call(url)
+    atom_url, body = FetchAtomService.new.(url)
+
+    return nil if atom_url.nil?
+    return process_atom(atom_url, body)
+  end
+
+  private
+
+  def process_atom(url, body)
+    url_parts = Addressable::URI.parse(url)
+    username  = xml.at_xpath('//xmlns:author/xmlns:name').try(:content)
+    domain    = url_parts.host
+
+    return nil if username.nil?
+
+    Rails.logger.debug "Going to webfinger #{username}@#{domain}"
+
+    return FollowRemoteAccountService.new.("#{username}@#{domain}")
+  end
+end

app/services/fetch_remote_status_service.rb

@@ -1,17 +1,9 @@
 class FetchRemoteStatusService < BaseService
   def call(url)
-    response = http_client.head(url)
+    atom_url, body = FetchAtomService.new.(url)
 
-    Rails.logger.debug "Remote status HEAD request returned code #{response.code}"
-    return nil if response.code != 200
-
-    if response.mime_type == 'application/atom+xml'
-      return process_atom(url, fetch(url))
-    elsif !response['Link'].blank?
-      return process_headers(response)
-    else
-      return process_html(fetch(url))
-    end
+    return nil if atom_url.nil?
+    return process_atom(atom_url, body)
   end
 
   private
@@ -29,26 +21,6 @@ class FetchRemoteStatusService < BaseService
     return statuses.first
   end
 
-  def process_html(body)
-    Rails.logger.debug "Processing HTML for remote status"
-
-    page = Nokogiri::HTML(body)
-    alternate_link = page.xpath('//link[@rel="alternate"]').find { |link| link['type'] == 'application/atom+xml' }
-
-    return nil if alternate_link.nil?
-    return process_atom(alternate_link['href'], fetch(alternate_link['href']))
-  end
-
-  def process_headers(response)
-    Rails.logger.debug "Processing link header for remote status"
-
-    link_header    = LinkHeader.parse(response['Link'])
-    alternate_link = link_header.find_link(['rel', 'alternate'], ['type', 'application/atom+xml'])
-
-    return nil if alternate_link.nil?
-    return process_atom(alternate_link.href, fetch(alternate_link.href))
-  end
-
   def extract_author(url, xml)
     url_parts = Addressable::URI.parse(url)
     username  = xml.at_xpath('//xmlns:author/xmlns:name').try(:content)
@@ -60,12 +32,4 @@ class FetchRemoteStatusService < BaseService
 
     return FollowRemoteAccountService.new.("#{username}@#{domain}")
   end
-
-  def fetch(url)
-    http_client.get(url).to_s
-  end
-
-  def http_client
-    HTTP.timeout(:per_operation, write: 20, connect: 20, read: 50)
-  end
 end

app/services/process_feed_service.rb

@@ -57,7 +57,11 @@ class ProcessFeedService < BaseService
     # and tidier
 
     links.each do |mention_link|
-      href = Addressable::URI.parse(mention_link.attribute('href').value)
+      href_val = mention_link.attribute('href').value
+
+      next if href_val == 'http://activityschema.org/collection/public'
+      
+      href = Addressable::URI.parse(href_val)
 
       if href.host == Rails.configuration.x.local_domain
         # A local user is mentioned
@@ -72,6 +76,10 @@ class ProcessFeedService < BaseService
         # This is kinda dodgy because URLs could change, we don't index them
         mentioned_account = Account.find_by(url: href.to_s)
 
+        if mentioned_account.nil?
+          mentioned_account = FetchRemoteAccountService.new.(href)
+        end
+
         unless mentioned_account.nil?
           mentioned_account.mentions.where(status: status).first_or_create(status: status)
         end

spec/controllers/api/subscriptions_controller_spec.rb

@@ -32,6 +32,11 @@ RSpec.describe Api::SubscriptionsController, type: :controller do
       stub_request(:head, "https://social.umeahackerspace.se/notice/424348").to_return(status: 404)
       stub_request(:head, "https://community.highlandarrow.com/notice/50467").to_return(status: 404)
       stub_request(:head, "https://quitter.no/notice/1243309").to_return(status: 404)
+      stub_request(:head, "https://quitter.no/user/7477").to_return(status: 404)
+      stub_request(:head, "https://community.highlandarrow.com/user/1").to_return(status: 404)
+      stub_request(:head, "https://social.umeahackerspace.se/user/2").to_return(status: 404)
+      stub_request(:head, "https://gs.kawa-kun.com/user/2").to_return(status: 404)
+      stub_request(:head, "https://mastodon.social/users/Gargron").to_return(status: 404)
       
       request.env['HTTP_X_HUB_SIGNATURE'] = "sha1=#{OpenSSL::HMAC.hexdigest('sha1', 'abc', feed)}"
       request.env['RAW_POST_DATA'] = feed

spec/services/fetch_atom_service_spec.rb

@@ -0,0 +1,4 @@
+require 'rails_helper'
+
+RSpec.describe FetchAtomService do
+end

spec/services/fetch_feed_service_spec.rb

@@ -1,8 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe FetchFeedService do
-  subject { FetchFeedService.new }
-
-  it 'fetches remote user\'s feed'
-  it 'processes the feed'
-end

spec/services/fetch_remote_account_service_spec.rb

@@ -0,0 +1,4 @@
+require 'rails_helper'
+
+RSpec.describe FetchRemoteAccountService do
+end

spec/services/fetch_remote_status_service_spec.rb

@@ -0,0 +1,4 @@
+require 'rails_helper'
+
+RSpec.describe FetchRemoteStatusService do
+end