HTTP CACHE CONTROL
|Cache-Control defines how, and for how long the individual response can be cached by the browser and other intermediate caches.
Cache-Control header was defined as part of the HTTP/1.1 specification and supersedes previous headers (e.g. Expires) used to define response caching policies.
The correct minimum set of headers that works across the most important browsers:
Cache-Control: no-cache, no-store, must-revalidate
Pragma: no-cache
Expires: 0
Add the following <meta> HTML tags to the page(s) you want to keep browsers from caching (the code must be in the <head> section of your page, for example right after <title> tag):
<meta http-equiv=”Cache-Control” content=”no-cache, no-store, must-revalidate” />
<meta http-equiv=”Pragma” content=”no-cache” />
<meta http-equiv=”Expires” content=”0″ />
.htaccess (Apache)
<IfModule mod_headers.c>
Header set Cache-Control “no-cache, no-store, must-revalidate”
Header set Pragma “no-cache”
Header set Expires 0
</IfModule>
Java Servlet
response.setHeader(“Cache-Control”, “no-cache, no-store, must-revalidate”);
response.setHeader(“Pragma”, “no-cache”);
response.setDateHeader(“Expires”, 0);
PHP
header(‘Cache-Control: no-cache, no-store, must-revalidate’); // HTTP 1.1.
header(‘Pragma: no-cache’); // HTTP 1.0.
header(‘Expires: 0’); // Proxies.
ASP.NET
Response.AppendHeader(“Cache-Control”, “no-cache, no-store, must-revalidate”);
Response.AppendHeader(“Pragma”, “no-cache”);
Response.AppendHeader(“Expires”, “0”);
ASP
Response.addHeader “Cache-Control”, “no-cache, no-store, must-revalidate”
Response.addHeader “Pragma”, “no-cache”
Response.addHeader “Expires”, “0”
Ruby on Rails
response.headers[‘Cache-Control’] = ‘no-cache, no-store, must-revalidate’
response.headers[‘Pragma’] = ‘no-cache’
response.headers[‘Expires’] = ‘0’
Python on Flask
resp.headers[“Cache-Control”] = “no-cache, no-store, must-revalidate”
resp.headers[“Pragma”] = “no-cache”
resp.headers[“Expires”] = “0”
Google Go
responseWriter.Header().Set(“Cache-Control”, “no-cache, no-store, must-revalidate”)
responseWriter.Header().Set(“Pragma”, “no-cache”)
responseWriter.Header().Set(“Expires”, “0”)