Module: Garner::Mixins::Grape::Cache

Defined in:
lib/garner/mixins/grape_cache.rb

Overview

A cache that supports conditional GETs

Borrows generously from themomorohoax.com/2009/01/07/using-stale-with-rails-to-return-304-not-modified See also RFC 2616: www.w3.org/Protocols/rfc2616/rfc2616-sec13.html#sec13.3.4

for explanation of how If-Modified-Since and If-None-Match request headers are handled.

Instance Method Summary collapse

Instance Method Details

#cache(options = {}, &block) ⇒ Object

cache a record



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# File 'lib/garner/mixins/grape_cache.rb', line 18

def cache(options = {}, &block)
  unless cache_enabled?
    yield
  else
    binding, context = cache_binding_and_context(options)
    Garner::Cache::ObjectIdentity.cache(binding, context) do
      yield
    end
  end
end

#cache_enabled? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/garner/mixins/grape_cache.rb', line 13

def cache_enabled?
  true
end

#cache_or_304(options = {}, &block) ⇒ Object 



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# File 'lib/garner/mixins/grape_cache.rb', line 34

def cache_or_304(options = {}, &block)
  unless cache_enabled?
    yield
  else
    binding, context = cache_binding_and_context(options)
    # metadata written in a previous GET
    metadata = Garner::Cache::ObjectIdentity.cache_metadata(binding, context)
    error!("Not Modified", 304) if metadata && fresh?(metadata)
    rc = cache(options, &block)
    # metadata has been generated by cache
    metadata = Garner::Cache::ObjectIdentity.cache_metadata(binding, context)
    if metadata
      self.last_modified = metadata[:last_modified]
      self.etag = metadata[:etag]
    end
    rc
  end
end

#invalidate(*args) ⇒ Object

invalidate a cache record



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# File 'lib/garner/mixins/grape_cache.rb', line 30

def invalidate(*args)
  Garner::Cache::ObjectIdentity.invalidate(* args)
end