32 lines
718 B
Ruby
32 lines
718 B
Ruby
# frozen_string_literal: true
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class DistributedMemoizer
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# never wait for longer that 1 second for a cross process lock
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MAX_WAIT = 1
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# memoize a key across processes and machines
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def self.memoize(key, duration = 60 * 60 * 24, redis = Discourse.redis)
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redis_lock_key = self.redis_lock_key(key)
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redis_key = self.redis_key(key)
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DistributedMutex.synchronize(redis_lock_key, redis: redis, validity: MAX_WAIT) do
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result = redis.get(redis_key)
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unless result
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result = yield
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redis.setex(redis_key, duration, result)
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end
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result
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end
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end
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def self.redis_lock_key(key)
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"memoize_lock_#{key}"
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end
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def self.redis_key(key)
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"memoize_#{key}"
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end
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end
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