Class: Flipper::Adapters::Memoizable

Inherits:
Object
  • Object
show all
Includes:
Flipper::Adapter
Defined in:
lib/flipper/adapters/memoizable.rb

Overview

Internal: Adapter that wraps another adapter with the ability to memoize adapter calls in memory. Used by flipper dsl and the memoizer middleware to make it possible to memoize adapter calls for the duration of a request.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Flipper::Adapter

#default_config, included, #name

Constructor Details

#initialize(adapter, cache = nil) ⇒ Memoizable

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 18

def initialize(adapter, cache = nil)
  @adapter = adapter
  @cache = cache || {}
  @memoize = false
  @features_key = :flipper_features
  @get_all_key = :all_memoized
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(name, *args, &block) ⇒ Object 



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# File 'lib/flipper/adapters/memoizable.rb', line 142

def method_missing(name, *args, **kwargs, &block)
  @adapter.send name, *args, **kwargs, &block
end

Instance Attribute Details

#adapter ⇒ Object (readonly)

Internal: The adapter this adapter is wrapping.



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# File 'lib/flipper/adapters/memoizable.rb', line 15

def adapter
  @adapter
end

#cache ⇒ Object (readonly)

Internal



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# File 'lib/flipper/adapters/memoizable.rb', line 12

def cache
  @cache
end

Instance Method Details

#add(feature) ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 36

def add(feature)
  @adapter.add(feature).tap { expire_features_set }
end

#clear(feature) ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 49

def clear(feature)
  @adapter.clear(feature).tap { expire_feature(feature) }
end

#disable(feature, gate, thing) ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 116

def disable(feature, gate, thing)
  @adapter.disable(feature, gate, thing).tap { expire_feature(feature) }
end

#enable(feature, gate, thing) ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 111

def enable(feature, gate, thing)
  @adapter.enable(feature, gate, thing).tap { expire_feature(feature) }
end

#export(format: :json, version: 1) ⇒ Object 



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# File 'lib/flipper/adapters/memoizable.rb', line 124

def export(format: :json, version: 1)
  @adapter.export(format: format, version: version)
end

#features ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 27

def features
  if memoizing?
    cache.fetch(@features_key) { cache[@features_key] = @adapter.features }
  else
    @adapter.features
  end
end

#get(feature) ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 54

def get(feature)
  if memoizing?
    cache.fetch(key_for(feature.key)) { cache[key_for(feature.key)] = @adapter.get(feature) }
  else
    @adapter.get(feature)
  end
end

#get_all ⇒ Object 



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# File 'lib/flipper/adapters/memoizable.rb', line 84

def get_all
  if memoizing?
    response = nil
    if cache[@get_all_key]
      response = {}
      cache[@features_key].each do |key|
        response[key] = cache[key_for(key)]
      end
    else
      response = @adapter.get_all
      response.each do |key, value|
        cache[key_for(key)] = value
      end
      cache[@features_key] = response.keys.to_set
      cache[@get_all_key] = true
    end

    # Ensures that looking up other features that do not exist doesn't
    # result in N+1 adapter calls.
    response.default_proc = ->(memo, key) { memo[key] = default_config }
    response
  else
    @adapter.get_all
  end
end

#get_multi(features) ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 63

def get_multi(features)
  if memoizing?
    uncached_features = features.reject { |feature| cache[key_for(feature.key)] }

    if uncached_features.any?
      response = @adapter.get_multi(uncached_features)
      response.each do |key, hash|
        cache[key_for(key)] = hash
      end
    end

    result = {}
    features.each do |feature|
      result[feature.key] = cache[key_for(feature.key)]
    end
    result
  else
    @adapter.get_multi(features)
  end
end

#import(source) ⇒ Object 



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# File 'lib/flipper/adapters/memoizable.rb', line 120

def import(source)
  @adapter.import(source).tap { cache.clear if memoizing? }
end

#memoize=(value) ⇒ Object

Internal: Turns local caching on/off.

value - The Boolean that decides if local caching is on.



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# File 'lib/flipper/adapters/memoizable.rb', line 131

def memoize=(value)
  cache.clear
  @memoize = value
end

#memoizing? ⇒ Boolean

Internal: Returns true for using local cache, false for not.

Returns:

  • (Boolean) 


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# File 'lib/flipper/adapters/memoizable.rb', line 137

def memoizing?
  !!@memoize
end

#remove(feature) ⇒ Object

Public



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# File 'lib/flipper/adapters/memoizable.rb', line 41

def remove(feature)
  @adapter.remove(feature).tap do
    expire_features_set
    expire_feature(feature)
  end
end