Class: Moneta::Expires

Inherits:
Proxy
  • Object
show all
Includes:
ExpiresSupport
Defined in:
lib/moneta/expires.rb

Overview

Adds expiration support to the underlying store

`#store`, `#load` and `#key?` support the `:expires` option to set/update the expiration time.

Instance Attribute Summary

Attributes included from ExpiresSupport

#default_expires

Attributes inherited from Proxy

#adapter

Instance Method Summary collapse

Methods inherited from Proxy

#clear, #close, #each_key, #features, features_mask, #increment, not_supports

Methods included from Defaults

#[], #[]=, #close, #decrement, #each_key, #features, #fetch, included, #increment, #supports?, #update

Methods included from OptionSupport

#expires, #prefix, #raw, #with

Constructor Details

#initialize(adapter, options = {}) ⇒ Expires

Returns a new instance of Expires

Parameters:

  • adapter (Moneta store)

    The underlying store

  • options (Hash) (defaults to: {})

Options Hash (options):

  • :expires (String)

    Default expiration time


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# File 'lib/moneta/expires.rb', line 14

def initialize(adapter, options = {})
  raise 'Store already supports feature :expires' if adapter.supports?(:expires)
  super
  self.default_expires = options[:expires]
end

Instance Method Details

#create(key, value, options = {}) ⇒ Object

Store value with key

Parameters:

  • key (Object)
  • value (Object)
  • options (Hash) (defaults to: {})

Options Hash (options):

  • :expires (Integer)

    Set expiration time (See Moneta::Expires)

  • :raw (Boolean)

    Raw access without value transformation (See Transformer)

  • :prefix (String)

    Prefix key (See Transformer)

  • Other (Object)

    options as defined by the adapters or middleware

Returns:

  • value


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# File 'lib/moneta/expires.rb', line 51

def create(key, value, options = {})
  return super if options.include?(:raw)
  expires = expires_at(options)
  @adapter.create(key, new_entry(value, expires), Utils.without(options, :expires))
end

#delete(key, options = {}) ⇒ Object

Delete the key from the store and return the current value

Parameters:

  • key (Object)
  • options (Hash) (defaults to: {})

Options Hash (options):

  • :raw (Boolean)

    Raw access without value transformation (See Transformer)

  • :prefix (String)

    Prefix key (See Transformer)

  • Other (Object)

    options as defined by the adapters or middleware

Returns:

  • (Object)

    current value


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# File 'lib/moneta/expires.rb', line 44

def delete(key, options = {})
  return super if options.include?(:raw)
  value, expires = super
  value if !expires || Time.now <= Time.at(expires)
end

#fetch_values(*keys, **options) ⇒ Object #fetch_values(*keys, **options) {|key| ... } ⇒ Array<Object, nil>

Note:

Some adapters may implement this method atomically. The default implmentation uses #values_at.

Behaves identically to #values_at except that it accepts an optional block. When supplied, the block will be called successively with each supplied key that is not present in the store. The return value of the block call will be used in place of nil in returned the array of values.

Overloads:

  • #fetch_values(*keys, **options) {|key| ... } ⇒ Array<Object, nil>

    Returns Array containing the values requested, or where keys are missing, the return values from the corresponding block calls

    Yield Parameters:

    • key (Object)

      Each key that is not found in the store

    Yield Returns:

    • (Object, nil)

      The value to substitute for the missing one

    Returns:

    • (Array<Object, nil>)

      Array containing the values requested, or where keys are missing, the return values from the corresponding block calls


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# File 'lib/moneta/expires.rb', line 75

def fetch_values(*keys, **options)
  return super if options.include?(:raw)
  new_expires = expires_at(options, nil)
  options = Utils.without(options, :expires)
  substituted = {}
  block = if block_given?
            lambda do |key|
              substituted[key] = true
              yield key
            end
          end

  with_updates(options) do |updates|
    keys.zip(@adapter.fetch_values(*keys, **options, &block)).map do |key, entry|
      next entry if substituted[key]
      entry = invalidate_entry(key, entry, new_expires) do |new_entry|
        updates[key] = new_entry
      end
      if entry.nil?
        value = if block_given?
                  yield key
                end
      else
        value, _ = entry
      end
      value
    end
  end
end

#key?(key, options = {}) ⇒ Boolean

Exists the value with key

Parameters:

  • key (Object)
  • options (Hash) (defaults to: {})

Options Hash (options):

  • :expires (Integer)

    Update expiration time (See Moneta::Expires)

  • :prefix (String)

    Prefix key (See Transformer)

  • Other (Object)

    options as defined by the adapters or middleware

Returns:

  • (Boolean)

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# File 'lib/moneta/expires.rb', line 21

def key?(key, options = {})
  # Transformer might raise exception
  load_entry(key, options) != nil
rescue Exception
  super(key, Utils.without(options, :expires))
end

#load(key, options = {}) ⇒ Object

Fetch value with key. Return nil if the key doesn't exist

Parameters:

  • key (Object)
  • options (Hash) (defaults to: {})

Options Hash (options):

  • :expires (Integer)

    Update expiration time (See Moneta::Expires)

  • :raw (Boolean)

    Raw access without value transformation (See Transformer)

  • :prefix (String)

    Prefix key (See Transformer)

  • :sync (Boolean)

    Synchronized load (Cache reloads from adapter, Adapters::Daybreak syncs with file)

  • Other (Object)

    options as defined by the adapters or middleware

Returns:

  • (Object)

    value


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# File 'lib/moneta/expires.rb', line 29

def load(key, options = {})
  return super if options.include?(:raw)
  value, expires = load_entry(key, options)
  value
end

#merge!(pairs, options = {}) ⇒ self #merge!(pairs, options = {}) {|key, old_value, new_value| ... } ⇒ self

Note:

Some adapters may implement this method atomically, or in two passes when a block is provided. The default implmentation uses #key?, #load and #store.

Stores the pairs in the key-value store, and returns itself. When a block is provided, it will be called before overwriting any existing values with the key, old value and supplied value, and the return value of the block will be used in place of the supplied value.

Overloads:

  • #merge!(pairs, options = {}) ⇒ self

    Parameters:

    • pairs (<(Object, Object)>)

      A collection of key-value pairs to store

    • options (Hash) (defaults to: {})

    Returns:

    • (self)
  • #merge!(pairs, options = {}) {|key, old_value, new_value| ... } ⇒ self

    Parameters:

    • pairs (<(Object, Object)>)

      A collection of key-value pairs to store

    • options (Hash) (defaults to: {})

    Yield Parameters:

    • key (Object)

      A key that whose value is being overwritten

    • old_value (Object)

      The existing value which is being overwritten

    • new_value (Object)

      The value supplied in the method call

    Yield Returns:

    • (Object)

      The value to use for overwriting

    Returns:

    • (self)

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# File 'lib/moneta/expires.rb', line 124

def merge!(pairs, options={})
  expires = expires_at(options)
  options = Utils.without(options, :expires)

  block = if block_given?
            lambda do |key, old_entry, entry|
              old_entry = invalidate_entry(key, old_entry)
              if old_entry.nil?
                entry # behave as if no replace is happening
              else
                old_value, _ = old_entry
                new_value, _ = entry
                new_entry(yield(key, old_value, new_value), expires)
              end
            end
          end

  entry_pairs = pairs.map do |key, value|
    [key, new_entry(value, expires)]
  end
  @adapter.merge!(entry_pairs, options, &block)
  self
end

#slice(*keys, **options) ⇒ <(Object, Object)>

Note:

The keys in the return value may be the same objects that were supplied (i.e. Object#equal?), or may simply be equal (i.e. Object#==).

Note:

Some adapters may implement this method atomically. The default implmentation uses #values_at.

Returns a collection of key-value pairs corresponding to those supplied keys which are present in the key-value store, and their associated values. Only those keys present in the store will have pairs in the return value. The return value can be any enumerable object that yields pairs, so it could be a hash, but needn't be.

Parameters:

  • keys (<Object>)

    The keys for the values to fetch

  • options (Hash)

Options Hash (**options):

  • :expires (Integer)

    Update expiration time (See Moneta::Expires)

  • :raw (Boolean)

    Raw access without value transformation (See Transformer)

  • :prefix (String)

    Prefix key (See Transformer)

  • :sync (Boolean)

    Synchronized load (Cache reloads from adapter, Adapters::Daybreak syncs with file)

  • Other (Object)

    options as defined by the adapters or middleware

Returns:

  • (<(Object, Object)>)

    A collection of key-value pairs


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# File 'lib/moneta/expires.rb', line 106

def slice(*keys, **options)
  return super if options.include?(:raw)
  new_expires = expires_at(options, nil)
  options = Utils.without(options, :expires)

  with_updates(options) do |updates|
    @adapter.slice(*keys, **options).map do |key, entry|
      entry = invalidate_entry(key, entry, new_expires) do |new_entry|
        updates[key] = new_entry
      end
      next if entry.nil?
      value, _ = entry
      [key, value]
    end.reject(&:nil?)
  end
end

#store(key, value, options = {}) ⇒ Object

Store value with key

Parameters:

  • key (Object)
  • value (Object)
  • options (Hash) (defaults to: {})

Options Hash (options):

  • :expires (Integer)

    Set expiration time (See Moneta::Expires)

  • :raw (Boolean)

    Raw access without value transformation (See Transformer)

  • :prefix (String)

    Prefix key (See Transformer)

  • Other (Object)

    options as defined by the adapters or middleware

Returns:

  • value


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# File 'lib/moneta/expires.rb', line 36

def store(key, value, options = {})
  return super if options.include?(:raw)
  expires = expires_at(options)
  super(key, new_entry(value, expires), Utils.without(options, :expires))
  value
end

#values_at(*keys, **options) ⇒ Array<Object, nil>

Note:

Some adapters may implement this method atomically, but the default implementation simply makes repeated calls to #load.

Returns an array containing the values associated with the given keys, in the same order as the supplied keys. If a key is not present in the key-value-store, nil is returned in its place.

Parameters:

  • keys (<Object>)

    The keys for the values to fetch

  • options (Hash)

Options Hash (**options):

  • :expires (Integer)

    Update expiration time (See Moneta::Expires)

  • :raw (Boolean)

    Raw access without value transformation (See Transformer)

  • :prefix (String)

    Prefix key (See Transformer)

  • :sync (Boolean)

    Synchronized load (Cache reloads from adapter, Adapters::Daybreak syncs with file)

  • Other (Object)

    options as defined by the adapters or middleware

Returns:

  • (Array<Object, nil>)

    Array containing the values requested, with nil for missing values


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# File 'lib/moneta/expires.rb', line 58

def values_at(*keys, **options)
  return super if options.include?(:raw)
  new_expires = expires_at(options, nil)
  options = Utils.without(options, :expires)
  with_updates(options) do |updates|
    keys.zip(@adapter.values_at(*keys, **options)).map do |key, entry|
      entry = invalidate_entry(key, entry, new_expires) do |new_entry|
        updates[key] = new_entry
      end
      next if entry.nil?
      value, _ = entry
      value
    end
  end
end