Struct CacheControl

pub struct CacheControl { /* private fields */ }

Directives to limit cache lifetime, read from cache-control and kvarn-cache-control headers.

See Self::from_cache_control and Self::from_kvarn_cache_control for respective parsing.

Implementations

impl CacheControl

pub fn from_cache_control( header: &str, ) -> Result<CacheControl, CacheControlError>

Respects max-age= and no-store parts of cache-control header.

Uses the standard syntax.

Errors

Can return CacheControlError::MultipleMaxAge and CacheControlError::InvalidInteger.

pub fn from_kvarn_cache_control( header: &str, ) -> Result<CacheControl, CacheControlError>

Converts a kvarn-cache-control header to a CacheControl directive.

The kvarn-cache-control header is used for reverse-proxy servers and other downstream sources to signal how Kvarn should cache their content. This header is prioritized over cache-control, but serves a similar function. This only applies to the server cache, whereas cache-control effects both the client and the server (if this header isn’t available).

See CacheControlError::InvalidUnit for available units.

Examples

To limit a response to be in the cache for 10 minutes, return kvarn-cache-control: 10m as a header in a reverse-proxied server or in a extension.

Errors

Can return CacheControlError::InvalidKeyword, CacheControlError::InvalidUnit, and CacheControlError::InvalidInteger.

pub fn from_headers( headers: &HeaderMap, ) -> Result<CacheControl, CacheControlError>

Tries to get CacheControl from a HeaderMap.

See Self::from_kvarn_cache_control for more info about how the server cache directive is decided.

Errors

Same as Self::from_kvarn_cache_control and Self::from_cache_control with CacheControlError::InvalidBytes if HeaderValue::to_str returns an error.

pub fn store(&self) -> bool

Returns if you should cache.

pub fn as_freshness(&self) -> Option<u32>

Gets the freshness lifetime of this cache control directive. If the returned value is None, you should let it be in the cache for as long as possible, longer than any with a defined lifetime.

Trait Implementations

impl Clone for CacheControl

fn clone(&self) -> CacheControl

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CacheControl

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.