Twitter retweet agent (#1181)

* Agent to retweet all received tweet events

* Cache twitter rest client

* Update description, remove unused local

* Makes context strings more readable, style consistency

* to_h is not implemented in ruby 2.0

* In error case, include all agent_ids and event_ids

* Adds capability to favorite tweets

This restructures the Agent slightly to allow for retweeting and
favoriting. It is possible to do both at the same time.

- Renames the Agent from TwitterRetweetAgent
to TwitterActionAgent.
- Specs refactored

app/concerns/twitter_concern.rb

@@ -36,7 +36,7 @@ module TwitterConcern
   end
 
   def twitter
-    Twitter::REST::Client.new do |config|
+    @twitter ||= Twitter::REST::Client.new do |config|
       config.consumer_key = twitter_consumer_key
       config.consumer_secret = twitter_consumer_secret
       config.access_token = twitter_oauth_token

app/models/agents/twitter_action_agent.rb

@@ -0,0 +1,74 @@
+module Agents
+  class TwitterActionAgent < Agent
+    include TwitterConcern
+
+    cannot_be_scheduled!
+
+    description <<-MD
+      The Twitter Action Agent is able to retweet or favorite tweets from the events it receives.
+
+      #{ twitter_dependencies_missing if dependencies_missing? }
+
+      It expects to consume events generated by twitter agents where the payload is a hash of tweet information. The existing TwitterStreamAgent is one example of a valid event producer for this Agent.
+
+      To be able to use this Agent you need to authenticate with Twitter in the [Services](/services) section first.
+
+      Set `expected_receive_period_in_days` to the maximum amount of time that you'd expect to pass between Events being received by this Agent.
+      Set `retweet` to either true or false.
+      Set `favorite` to either true or false.
+    MD
+
+    def validate_options
+      unless options['expected_receive_period_in_days'].present?
+        errors.add(:base, "expected_receive_period_in_days is required")
+      end
+      unless retweet? || favorite?
+        errors.add(:base, "at least one action must be true")
+      end
+    end
+
+    def working?
+      last_receive_at && last_receive_at > interpolated['expected_receive_period_in_days'].to_i.days.ago && !recent_error_logs?
+    end
+
+    def default_options
+      {
+        'expected_receive_period_in_days' => '2',
+        'favorite' => 'false',
+        'retweet' => 'true',
+      }
+    end
+
+    def retweet?
+      boolify(options['retweet'])
+    end
+
+    def favorite?
+      boolify(options['favorite'])
+    end
+
+    def receive(incoming_events)
+      tweets = tweets_from_events(incoming_events)
+
+      begin
+        twitter.favorite(tweets) if favorite?
+        twitter.retweet(tweets) if retweet?
+      rescue Twitter::Error => e
+        create_event :payload => {
+          'success' => false,
+          'error' => e.message,
+          'tweets' => Hash[tweets.map { |t| [t.id, t.text] }],
+          'agent_ids' => incoming_events.map(&:agent_id),
+          'event_ids' => incoming_events.map(&:id)
+        }
+      end
+    end
+
+    def tweets_from_events(events)
+      events.map do |e|
+        Twitter::Tweet.new(id: e.payload["id"], text: e.payload["text"])
+      end
+    end
+  end
+end
+

spec/models/agents/twitter_action_agent_spec.rb

@@ -0,0 +1,158 @@
+require 'rails_helper'
+
+describe Agents::TwitterActionAgent do
+  describe '#receive' do
+    before do
+      @event1 = Event.new
+      @event1.agent = agents(:bob_twitter_user_agent)
+      @event1.payload = { id: 123, text: 'So awesome.. gotta retweet' }
+      @event1.save!
+      @tweet1 = Twitter::Tweet.new(
+        id: @event1.payload[:id],
+        text: @event1.payload[:text]
+      )
+
+      @event2 = Event.new
+      @event2.agent = agents(:bob_twitter_user_agent)
+      @event2.payload = { id: 456, text: 'Something Justin Bieber said' }
+      @event2.save!
+      @tweet2 = Twitter::Tweet.new(
+        id: @event2.payload[:id],
+        text: @event2.payload[:text]
+      )
+    end
+
+    context 'when set up to retweet' do
+      before do
+        @agent = build_agent({
+          'expected_receive_period_in_days' => '2',
+          'favorite' => 'false',
+          'retweet' => 'true',
+        })
+        @agent.save!
+      end
+
+      context 'when the twitter client succeeds retweeting' do
+        it 'should retweet the tweets from the payload' do
+          mock(@agent.twitter).retweet([@tweet1, @tweet2])
+          @agent.receive([@event1, @event2])
+        end
+      end
+
+      context 'when the twitter client fails retweeting' do
+        it 'creates an event with tweet info and the error message' do
+          stub(@agent.twitter).retweet(anything) {
+            raise Twitter::Error.new('uh oh')
+          }
+
+          @agent.receive([@event1, @event2])
+
+          failure_event = @agent.events.last
+          expect(failure_event.payload[:error]).to eq('uh oh')
+          expect(failure_event.payload[:tweets]).to eq(
+            {
+              @event1.payload[:id].to_s => @event1.payload[:text],
+              @event2.payload[:id].to_s => @event2.payload[:text]
+            }
+          )
+          expect(failure_event.payload[:agent_ids]).to match_array(
+            [@event1.agent_id, @event2.agent_id]
+          )
+          expect(failure_event.payload[:event_ids]).to match_array(
+            [@event2.id, @event1.id]
+          )
+        end
+      end
+    end
+
+    context 'when set up to favorite' do
+      before do
+        @agent = build_agent(
+          'expected_receive_period_in_days' => '2',
+          'favorite' => 'true',
+          'retweet' => 'false',
+        )
+        @agent.save!
+      end
+
+      context 'when the twitter client succeeds favoriting' do
+        it 'should favorite the tweets from the payload' do
+          mock(@agent.twitter).favorite([@tweet1, @tweet2])
+          @agent.receive([@event1, @event2])
+        end
+      end
+
+      context 'when the twitter client fails retweeting' do
+        it 'creates an event with tweet info and the error message' do
+          stub(@agent.twitter).favorite(anything) {
+            raise Twitter::Error.new('uh oh')
+          }
+
+          @agent.receive([@event1, @event2])
+
+          failure_event = @agent.events.last
+          expect(failure_event.payload[:error]).to eq('uh oh')
+          expect(failure_event.payload[:tweets]).to eq(
+            {
+              @event1.payload[:id].to_s => @event1.payload[:text],
+              @event2.payload[:id].to_s => @event2.payload[:text]
+            }
+          )
+          expect(failure_event.payload[:agent_ids]).to match_array(
+            [@event1.agent_id, @event2.agent_id]
+          )
+          expect(failure_event.payload[:event_ids]).to match_array(
+            [@event2.id, @event1.id]
+          )
+        end
+      end
+    end
+  end
+
+  describe "#validate_options" do
+    context 'when set up to neither favorite or retweet' do
+      it 'is invalid' do
+        agent = build_agent(
+          'expected_receive_period_in_days' => '2',
+          'favorite' => 'false',
+          'retweet' => 'false',
+        )
+
+        expect(agent).not_to be_valid
+      end
+    end
+  end
+
+  describe '#working?' do
+    before do
+      stub.any_instance_of(Twitter::REST::Client).retweet(anything)
+    end
+
+    it 'checks if events have been received within the expected time period' do
+      agent = build_agent(
+        'expected_receive_period_in_days' => '2',
+        'favorite' => 'false',
+        'retweet' => 'true',
+      )
+      agent.save!
+
+      expect(agent).not_to be_working # No events received
+
+      described_class.async_receive(agent.id, [events(:bob_website_agent_event)])
+      expect(agent.reload).to be_working # Just received events
+
+      two_days_from_now = 2.days.from_now
+      stub(Time).now { two_days_from_now }
+      expect(agent.reload).not_to be_working # Too much time has passed
+    end
+  end
+
+  def build_agent(options)
+    described_class.new do |agent|
+      agent.name = 'twitter stuff'
+      agent.options = options
+      agent.service = services(:generic)
+      agent.user = users(:bob)
+    end
+  end
+end