HTTP Header

HTTP headers define various characteristics of the data that is requested or the data that has been provided.

e.g.: Cache-Control tells all caching mechanisms from server to client whether they may cache this object.

Cache-Control: max-age=0, no-cache, no-store, must-revalidate

Here you can define custom HTTP headers which are returned (provided) as a part of the response to a browser request.

Figure. HTTP reader tab.

Field	Description
Expiration	You can use this option to include an expiration HTTP header in the response. A browser compares the date in expiration header to the current one and decides whether the cached page should be shown or a new version should be requested. None: The cache page would be shown if any already exists. Immediate: The browser would have to request updated page anytime it tries to access that page. After minutes: It sets the expiration period to the current time plus the number of minutes specified.
Custom HTTP Header Items	This allows you to define special headers that will be returned to a browser as a part of the response. Press the Add button to open the Header dialog box: Specify the name of the Header and the content (Value) you wish to insert.

Field

Description

Expiration

You can use this option to include an expiration HTTP header in the response. A browser compares the date in expiration header to the current one and decides whether the cached page should be shown or a new version should be requested.

None: The cache page would be shown if any already exists.
Immediate: The browser would have to request updated page anytime it tries to access that page.
After minutes: It sets the expiration period to the current time plus the number of minutes specified.

Custom HTTP Header Items

This allows you to define special headers that will be returned to a browser as a part of the response.

Press the Add button to open the Header dialog box:

Specify the name of the Header and the content (Value) you wish to insert.