module Agents class TwitterStreamAgent < Agent include TwitterConcern cannot_receive_events! description <<-MD #{twitter_dependencies_missing if dependencies_missing?} The TwitterStreamAgent follows the Twitter stream in real time, watching for certain keywords, or filters, that you provide. To follow the Twitter stream, provide an array of `filters`. Multiple words in a filter must all show up in a tweet, but are independent of order. If you provide an array instead of a filter, the first entry will be considered primary and any additional values will be treated as aliases. To be able to use this Agent you need to authenticate with Twitter in the [Services](/services) section first. Set `expected_update_period_in_days` to the maximum amount of time that you'd expect to pass between Events being created by this Agent. `generate` should be either `events` or `counts`. If set to `counts`, it will output event summaries whenever the Agent is scheduled. MD event_description <<-MD When in `counts` mode, TwitterStreamAgent events look like: { "filter": "hello world", "count": 25, "time": 3456785456 } When in `events` mode, TwitterStreamAgent events look like: { "filter": "selectorgadget", ... every Tweet field, including ... "text": "something", "user": { "name": "Mr. Someone", "screen_name": "Someone", "location": "Vancouver BC Canada", "description": "...", "followers_count": 486, "friends_count": 1983, "created_at": "Mon Aug 29 23:38:14 +0000 2011", "time_zone": "Pacific Time (US & Canada)", "statuses_count": 3807, "lang": "en" }, "retweet_count": 0, "entities": ... "lang": "en" } MD default_schedule "11pm" def validate_options unless options['filters'].present? && options['expected_update_period_in_days'].present? && options['generate'].present? errors.add(:base, "expected_update_period_in_days, generate, and filters are required fields") end end def working? event_created_within?(interpolated['expected_update_period_in_days']) && !recent_error_logs? end def default_options { 'filters' => %w[keyword1 keyword2], 'expected_update_period_in_days' => "2", 'generate' => "events" } end def process_tweet(filter, status) filter = lookup_filter(filter) if filter if interpolated['generate'] == "counts" # Avoid memory pollution by reloading the Agent. agent = Agent.find(id) agent.memory['filter_counts'] ||= {} agent.memory['filter_counts'][filter] ||= 0 agent.memory['filter_counts'][filter] += 1 remove_unused_keys!(agent, 'filter_counts') agent.save! else create_event :payload => status.merge('filter' => filter) end end end def check if interpolated['generate'] == "counts" && memory['filter_counts'] && memory['filter_counts'].length > 0 memory['filter_counts'].each do |filter, count| create_event :payload => { 'filter' => filter, 'count' => count, 'time' => Time.now.to_i } end end memory['filter_counts'] = {} end protected def lookup_filter(filter) interpolated['filters'].each do |known_filter| if known_filter == filter return filter elsif known_filter.is_a?(Array) if known_filter.include?(filter) return known_filter.first end end end end def remove_unused_keys!(agent, base) if agent.memory[base] (agent.memory[base].keys - agent.interpolated['filters'].map {|f| f.is_a?(Array) ? f.first.to_s : f.to_s }).each do |removed_key| agent.memory[base].delete(removed_key) end end end end end