You are in full control of how Fastly caches your resources. The most preferred way of instructing Fastly is to use backend HTTP headers.This header caches content until it expires as specified. It will be respected by Fastly caches, any caches between Fastly and the browser and the browser itself. This is the second of a 2 part article series dealing with HTTP headers. The first article focused on Content-Type and Content-Disposition. In this article well be talking about caching content and how browsers react differently to headers like Cache-Control, Expires, Last-Modified and Pragma. Servers specify explicit expiration times using either the Expires header, or the max-age directive of the Cache-Control header.to avoid using HTTP expiration controls and cache controls when. If a response includes both an Expires and a Cache-Control max-age directive, the max-age overrides the Expires header, even if the Expires header is more restrictive. This rule allows an origin server to provide, for a given response, a longer expiration time to an HTTP/1.1 cache than to an HTTP/1.0 Cache-Control Header. Modifications of the Basic Expiration Mechanism. Cache Revalidation and Reload Controls.Caching with modexpires. This module controls the setting of the Expires HTTP header and the max-age directive of the Cache-Control HTTP header in server responses. When I check the HTTP request header fields, I get the following output: Expires: Thu, 19 Nov 1981 08:52:00 GMT Cache-Control: no-store, no-cache, must-revalidate, post-check0, pre-check0 Pragma: no-cache. In HTTP 1.1, the Expires header was deprecated and Cache-Control is the alternative. If both Expires and Cache-Control headers are found, Expires will be ignored.It does so my looking at the Cache-Control or Expires headers.
If we can write our own headers, then why not write Cache-control or Expires headers? The module contains two directives that allow us customize HTTP response. Header allows us to write 1xx and 2xx headers and ErrorHeader allows us to write 3xx, 4xx and 5xx headers. Extension Cache-Control directives are not part of the core HTTP caching standards document.s-maxage. Overrides max-age or the Expires header, but it only applies to shared caches (e.g proxies) and is ignored by a private cache. Cache-Control is a HTTP header that defines the amount of time and manner a file is to be cached.NGINX.
Using the expires directive you can add cache instructions to a server or location block. Generation of Expires and Cache-Control HTTP headers according to user-specified criteria.ExpiresActive On. Set default expires to 2 days. ExpiresDefault A172800. ExpiresByType text/css A31536000. In the example provided above, we are setting the Cache-Control header (using the constant values defined in Microsoft.Net. Http.Headers) to cache ourOnce the max-age duration we specified has expired, or after the browser evicts the files from its cache, well be back to making requests to the Cache-control used to control the HTTP cache (not part of the HTTP/1.0 implementation may only achieve a Pragma: no-cache).Expires said there is time, allow the client to not check in before this time (made the request), equivalent to max-age effect. HTML Cache control is a very similar question and has a good link to a caching tutorial that should answer most of your questions (e.g httpIf a document is delivered with no Expires or Cache-Control headers, how long will browsers cache the document? The Cache-Control header can be used to expire content immediately or disable caching altogether.HTTP allows caches to take liberties with the freshness of objects specifying this header tells the cache to strictly follow your rules. Introduction to HTTP Caching. The Cache-Control Header.