最後更新: 2016-10-14

介紹

它是一個設定 responses header 的 module 來, 它會設定

• "Expires: ..."HTTP header
• "Cache-Control: max-age=xxx"  HTTP header
  (max-age directive of the Cache-Control)

 * 有時用 "Header set Cache-Control "max-age=600, public"" 可能會簡單一點

ExpiresByType 設定

Enables or Disables

ExpiresActive On|Off

設定過期時間

ExpiresDefault  "base [[plus] num type] [num type] ..."

ExpiresByType  type/encoding  "base [[plus] num] [num type]"

base:

• access
• modification

time unit:

• years
• months
• weeks
• days
• hours
• minutes
• seconds

Example:

.htaccess

<IfModule mod_expires.c>
   ExpiresActive On
   # txt
   ExpiresByType application/x-javascript "access plus 30 minutes"
   ExpiresByType text/css "access plus 30 minutes"
   # 圖
   ExpiresByType image/png "access plus 30 minutes"
   ExpiresByType image/gif "access plus 30 minutes"
   ExpiresByType image/jpg "access plus 30 minutes"
   ExpiresByType image/jpeg "access plus 30 minutes"
   # 片
   ExpiresByType application/x-shockwave-flash "access plus 30 minutes"
   ExpiresByType video/mp4 "access plus 30 minutes"
   ExpiresByType video/avi "access plus 30 minutes"
</IfModule>

OR

# image file
<FilesMatch "\.(jpe?g|png|bmp|gif)$">
    ExpiresActive On
    ExpiresDefault "access plus 1 week"
</FilesMatch>

P.S.

/etc/mime.types

ExpiresDefault 設定

# It can be overridden on a type-by-type basis by the ExpiresByType directive.

i.e.

ExpiresDefault "access plus 30 minutes"

Client Side View

# 留意 Cache-Control 及 Expires