略過至「內容」 略過至「搜尋」
方法
E
F
I
N

常數

HTTP_IF_MODIFIED_SINCE = "HTTP_IF_MODIFIED_SINCE"
 
HTTP_IF_NONE_MATCH = "HTTP_IF_NONE_MATCH"
 

實例公開方法

etag_matches?(etag)

# 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

fresh?(response)

檢查回應的新鮮度(Last-ModifiedETag)相對於請求的 If-Modified-SinceIf-None-Match 條件。如果同時提供這兩個標頭,則根據設定,ETag 優先於 Last-Modified,或兩者一視同仁。你可以使用 config.action_dispatch.strict_freshness 調整偏好設定。參考: tools.ietf.org/html/rfc7232#section-6

# 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

if_modified_since()

# 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

if_none_match()

# File actionpack/lib/action_dispatch/http/cache.rb, line 20
def if_none_match
  get_header HTTP_IF_NONE_MATCH
end

if_none_match_etags()

# 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

not_modified?(modified_at)

# 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