Last update: 2022-06-02
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Client cache time to live. Number of hours until expiration. Used to manage client and proxy server caching.

See catalog::Expiration for details.


Real number, -2, -1, 0, or greater. Number of hours until expiration since the response image was generated. Set to 0 to always expire the response image immediately, which effectively disables client caching. Set to -1 to mark as never expire; in this case the server always returns 403 status in response to conditional GET requests without checking whether the file has actually changed. Set to -2 to use the default provided by attribute::Expiration.


attribute::Expiration is used if the field is not present, if the value is -2, or if the field is empty.

See also

attribute::Expiration , catalog::Expiration, req=

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