Class: Merb::Cache::MemoryStore

Inherits:
Object
  • Object
show all
Defined in:
lib/merb-cache/cache-store/memory.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ MemoryStore

Provides the memory cache store for merb-cache



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# File 'lib/merb-cache/cache-store/memory.rb', line 4

def initialize
  @config = Merb::Controller._cache.config
  @cache = {}
  @mutex = Mutex.new
  prepare
end

Instance Method Details

#cache(_controller, key, from_now = nil, &block) ⇒ Object

Capture or restore the data in cache. If the cache entry expired or does not exist, the data are taken from the execution of the block, marshalled and stored in cache. Otherwise, the data are loaded from the cache and returned unmarshalled

Parameters

_controller<Merb::Controller>

The instance of the current controller

key<String>

The key identifying the cache entry

from_now<~minutes>

The number of minutes (from now) the cache should persist

&block

The template to be used or not

Additional information

When fetching data (the cache entry exists and has not expired) The data are loaded from the cache and returned unmarshalled. Otherwise: The controller is used to capture the rendered template (from the block). It uses the capture_#engine and concat_#engine methods to do so. The captured data are then marshalled and stored.



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# File 'lib/merb-cache/cache-store/memory.rb', line 52

def cache(_controller, key, from_now = nil, &block)
  if @cache.key?(key)
    _data, _expire = *cache_read(key)
    _cache_hit = _expire.nil? || Time.now < _expire
  end
  unless _cache_hit
    _expire = from_now ? from_now.minutes.from_now : nil
    _data = _controller.send(:capture, &block)
    cache_write(key, [_data, _expire])
  end
  _controller.send(:concat, _data, block.binding)
  true
end

#cache_get(key) ⇒ Object

Fetch data from the file using the specified key The entry is deleted if it has expired

Parameter

key<Sting>

The key identifying the cache entry

Returns

data<String, NilClass>

nil is returned whether the entry expired or was not found



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# File 'lib/merb-cache/cache-store/memory.rb', line 89

def cache_get(key)
  if @cache.key?(key)
    _data, _expire = *cache_read(key)
    if _expire.nil? || Time.now < _expire
      Merb.logger.info("cache: hit (#{key})")
      return _data
    end
    @mutex.synchronize do @cache.delete(key) end
  end
  Merb.logger.info("cache: miss (#{key})")
  nil
end

#cache_set(key, data, from_now = nil) ⇒ Object

Store data to the file using the specified key

Parameters

key<Sting>

The key identifying the cache entry

data<String>

The data to be put in cache

from_now<~minutes>

The number of minutes (from now) the cache should persist



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# File 'lib/merb-cache/cache-store/memory.rb', line 73

def cache_set(key, data, from_now = nil)
  _expire = from_now ? from_now.minutes.from_now : nil
  cache_write(key, [data, _expire])
  Merb.logger.info("cache: set (#{key})")
  true
end

#cache_store_type ⇒ Object

Gives info on the current cache store

Returns

The type of the current cache store



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# File 'lib/merb-cache/cache-store/memory.rb', line 139

def cache_store_type
  "memory"
end

#cached?(key) ⇒ Boolean

Checks whether a cache entry exists

Parameter

key<String>

The key identifying the cache entry

Returns

true if the cache entry exists, false otherwise

Returns:

  • (Boolean) 


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# File 'lib/merb-cache/cache-store/memory.rb', line 24

def cached?(key)
  if @cache.key?(key)
    _data, _expire = *cache_read(key)
    return true if _expire.nil? || Time.now < _expire
    expire(key)
  end
  false
end

#expire(key) ⇒ Object

Expire the cache entry identified by the given key

Parameter

key<Sting>

The key identifying the cache entry



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# File 'lib/merb-cache/cache-store/memory.rb', line 106

def expire(key)
  @mutex.synchronize do
    @cache.delete(key)
  end
  Merb.logger.info("cache: expired (#{key})")
  true
end

#expire_all ⇒ Object

Expire all the cache entries



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# File 'lib/merb-cache/cache-store/memory.rb', line 127

def expire_all
  @mutex.synchronize do
    @cache.clear
  end
  Merb.logger.info("cache: expired all")
  true
end

#expire_match(key) ⇒ Object

Expire the cache entries matching the given key

Parameter

key<Sting>

The key matching the cache entries



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# File 'lib/merb-cache/cache-store/memory.rb', line 118

def expire_match(key)
  @mutex.synchronize do
    @cache.delete_if do |k,v| k.match(/#{key}/) end
  end
  Merb.logger.info("cache: expired matching (#{key})")
  true
end

#prepare ⇒ Object

This method is there to ensure minimal requirements are met (directories are accessible, table exists, connected to server, …)



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# File 'lib/merb-cache/cache-store/memory.rb', line 13

def prepare
  true
end