62 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			Ruby
		
	
	
	
	
	
			
		
		
	
	
			62 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			Ruby
		
	
	
	
	
	
| # frozen_string_literal: true
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| 
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| class Scheduler::FollowRecommendationsScheduler
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|   include Sidekiq::Worker
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|   include Redisable
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| 
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|   sidekiq_options retry: 0, lock: :until_executed, lock_ttl: 1.day.to_i
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| 
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|   # The maximum number of accounts that can be requested in one page from the
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|   # API is 80, and the suggestions API does not allow pagination. This number
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|   # leaves some room for accounts being filtered during live access
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|   SET_SIZE = 100
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| 
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|   def perform
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|     # Maintaining a materialized view speeds-up subsequent queries significantly
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|     AccountSummary.refresh
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|     FollowRecommendation.refresh
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| 
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|     fallback_recommendations = FollowRecommendation.order(rank: :desc).limit(SET_SIZE)
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| 
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|     Trends.available_locales.each do |locale|
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|       recommendations = if AccountSummary.safe.filtered.localized(locale).exists? # We can skip the work if no accounts with that language exist
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|                           FollowRecommendation.localized(locale).order(rank: :desc).limit(SET_SIZE).map { |recommendation| [recommendation.rank, recommendation.account_id] }
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|                         else
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|                           []
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|                         end
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| 
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|       # Use language-agnostic results if there are not enough language-specific ones
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|       missing = SET_SIZE - recommendations.size
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| 
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|       if missing.positive? && fallback_recommendations.size.positive?
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|         max_fallback_rank = fallback_recommendations.first.rank || 0
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| 
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|         # Language-specific results should be above language-agnostic ones,
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|         # otherwise language-agnostic ones will always overshadow them
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|         recommendations.map! { |(rank, account_id)| [rank + max_fallback_rank, account_id] }
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| 
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|         added = 0
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| 
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|         fallback_recommendations.each do |recommendation|
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|           next if recommendations.any? { |(_, account_id)| account_id == recommendation.account_id }
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| 
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|           recommendations << [recommendation.rank, recommendation.account_id]
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|           added += 1
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| 
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|           break if added >= missing
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|         end
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|       end
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| 
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|       redis.multi do |multi|
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|         multi.del(key(locale))
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|         multi.zadd(key(locale), recommendations)
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|       end
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|     end
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|   end
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| 
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|   private
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| 
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|   def key(locale)
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|     "follow_recommendations:#{locale}"
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|   end
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| end
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