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module ActionDispatch::Http::Cache::Request

Constants

"HTTP_IF_MODIFIED_SINCE"
"HTTP_IF_NONE_MATCH"

Public instance methods

Source code GitHub
# File actionpack/lib/action_dispatch/http/cache.rb, line 32
def etag_matches?(etag)
  if etag
    validators = if_none_match_etags
    validators.include?(etag) || validators.include?("*")
  end
end

Check response freshness (Last-Modified and ETag) against request If-Modified-Since and If-None-Match conditions. If both headers are supplied, based on configuration, either ETag is preferred over Last-Modified or both are considered equally. You can adjust the preference with config.action_dispatch.strict_freshness. Reference: tools.ietf.org/html/rfc7232#section-6

Source code GitHub
# File actionpack/lib/action_dispatch/http/cache.rb, line 45
def fresh?(response)
  if Request.strict_freshness
    if if_none_match
      etag_matches?(response.etag)
    elsif if_modified_since
      not_modified?(response.last_modified)
    else
      false
    end
  else
    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
end
Source code GitHub
# File actionpack/lib/action_dispatch/http/cache.rb, line 14
def if_modified_since
  if since = get_header(HTTP_IF_MODIFIED_SINCE)
    Time.rfc2822(since) rescue nil
  end
end
Source code GitHub
# File actionpack/lib/action_dispatch/http/cache.rb, line 20
def if_none_match
  get_header HTTP_IF_NONE_MATCH
end
Source code GitHub
# File actionpack/lib/action_dispatch/http/cache.rb, line 24
def if_none_match_etags
  if_none_match ? if_none_match.split(",").each(&:strip!) : []
end
Source code GitHub
# File actionpack/lib/action_dispatch/http/cache.rb, line 28
def not_modified?(modified_at)
  if_modified_since && modified_at && if_modified_since >= modified_at
end

Definition files