HTTPHeaders.CacheControl

Topics

Structures

• HTTPHeaders.CacheControl.MaxStale
  The max-stale option can be present with no value, or be present with a number of seconds. By using a struct you can check the nullability of the maxStale variable as well as then check the nullability of the seconds to differentiate.

Initializers

• init(mustRevalidated:noCache:noStore:noTransform:isPublic:isPrivate:proxyRevalidate:onlyIfCached:immutable:maxAge:sMaxAge:maxStale:minFresh:staleWhileRevalidate:staleIfError:)
  Creates a new CacheControl.

Instance Properties

• immutable
  Indicates that the response body will not change over time.
• isPrivate
  The response is for a single user and must not be stored by a shared cache. A private cache (like the user’s browser cache) may store the response.
• isPublic
  The response may be cached by any cache, even if the response is normally non-cacheable
• maxAge
  The maximum amount of time a resource is considered fresh. Unlike theExpires header, this directive is relative to the time of the request.
• maxStale
  Indicates the client will accept a stale response. An optional value in seconds indicates the upper limit of staleness the client will accept.
• minFresh
  Indicates the client wants a response that will still be fresh for at least the specified number of seconds.
• mustRevalidate
  Indicates that once a resource becomes stale, caches must not use their stale copy without successful validation on the origin server.
• noCache
  Caches must check with the origin server for validation before using the cached copy.
• noStore
  The cache should not store anything about the client request or server response.
• noTransform
  No transformations or conversions should be made to the resource. The Content-Encoding, Content-Range, Content-Type headers must not be modified by a proxy. A non-transparent proxy or browser feature such as Google’s Light Mode might, for example, convert between image formats in order to save cache space or to reduce the amount of traffic on a slow link. The no-transform directive disallows this.
• onlyIfCached
  Indicates to not retrieve new data. This being the case, the server wishes the client to obtain a response only once and then cache. From this moment the client should keep releasing a cached copy and avoid contacting the origin-server to see if a newer copy exists.
• proxyRevalidate
  Like must-revalidate, but only for shared caches (e.g., proxies). Ignored by private caches.
• sMaxAge
  Overrides max-age or the Expires header, but only for shared caches (e.g., proxies). Ignored by private caches.
• staleIfError
  Indicates the client will accept a stale response if the check for a fresh one fails. The value indicates how many seconds long the client will accept the stale response after the initial expiration.
• staleWhileRevalidate
  Indicates the client will accept a stale response, while asynchronously checking in the background for a fresh one. The value indicates how long the client will accept a stale response.

Instance Methods

• serialize()
  Generates the header string for this instance.

Type Methods

• parse(_:)