method

decrement

v7.1.3.4 - Show latest stable - Class: ActiveSupport::Cache::RedisCacheStore

decrement(name, amount = 1, options = nil)

public

Decrement a cached integer value using the Redis decrby atomic operator. Returns the updated value.

If the key is unset or has expired, it will be set to -amount:

cache.decrement("foo") # => -1

To set a specific value, call #write passing raw: true:

cache.write("baz", 5, raw: true)
cache.decrement("baz") # => 4

Decrementing a non-numeric value, or a value written without raw: true, will fail and return nil.

Failsafe: Raises errors.

# File activesupport/lib/active_support/cache/redis_cache_store.rb, line 262
      def decrement(name, amount = 1, options = nil)
        instrument :decrement, name, amount: amount do
          failsafe :decrement do
            options = merged_options(options)
            key = normalize_key(name, options)
            change_counter(key, -amount, options)
          end
        end
      end

decrement

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