Module: ActionDispatch::Http::Cache::Request

Included in:
Request
Defined in:
actionpack/lib/action_dispatch/http/cache.rb

Constant Summary collapse

HTTP_IF_MODIFIED_SINCE =
'HTTP_IF_MODIFIED_SINCE'.freeze
HTTP_IF_NONE_MATCH =
'HTTP_IF_NONE_MATCH'.freeze

Instance Method Summary collapse

Instance Method Details

#etag_matches?(etag) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'actionpack/lib/action_dispatch/http/cache.rb', line 27

def etag_matches?(etag)
  if etag
    validators = if_none_match_etags
    validators.include?(etag) || validators.include?('*')
  end
end

#fresh?(response) ⇒ Boolean

Check response freshness (Last-Modified and ETag) against request If-Modified-Since and If-None-Match conditions. If both headers are supplied, both must match, or the request is not considered fresh.

Returns:

  • (Boolean)

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# File 'actionpack/lib/action_dispatch/http/cache.rb', line 37

def fresh?(response)
  last_modified = if_modified_since
  etag          = if_none_match

  return false unless last_modified || etag

  success = true
  success &&= not_modified?(response.last_modified) if last_modified
  success &&= etag_matches?(response.etag) if etag
  success
end

#if_modified_sinceObject


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# File 'actionpack/lib/action_dispatch/http/cache.rb', line 9

def if_modified_since
  if since = get_header(HTTP_IF_MODIFIED_SINCE)
    Time.rfc2822(since) rescue nil
  end
end

#if_none_matchObject


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# File 'actionpack/lib/action_dispatch/http/cache.rb', line 15

def if_none_match
  get_header HTTP_IF_NONE_MATCH
end

#if_none_match_etagsObject


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# File 'actionpack/lib/action_dispatch/http/cache.rb', line 19

def if_none_match_etags
  if_none_match ? if_none_match.split(/\s*,\s*/) : []
end

#not_modified?(modified_at) ⇒ Boolean

Returns:

  • (Boolean)

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# File 'actionpack/lib/action_dispatch/http/cache.rb', line 23

def not_modified?(modified_at)
  if_modified_since && modified_at && if_modified_since >= modified_at
end