CODEWITHSUNDEEP
htmlcachingbrowserhyperlink
dukevin
dukevin

Reputation: 23178

HTML link that bypasses cache?

I have a file that I link to from my website like

<a href="http://example.com/myfile.txt>View!</a>

However, this file changes very frequently and when the link is clicked, the browser loads the cached version of the file, not the actual file. Is there a way so that clicking on that link will bypass the cache for that page?

Something nice like <a bypassCache href=""> would be wishful thinking.

Upvotes: 25

Views: 38572

Answers (5)

Pekka
Pekka

Reputation: 449385

Something nice like would be wishful thinking.

Indeed, there is something you can do from within the link: Add a random GET parameter.

<a href="http://example.com/myfile.txt?a=193834923283943842923">View!</a>

You could use JavaScript (or of course a server-side scripting language like PHP) to do this on a dynamic basis.

However, the far superior way would be to configure the text file's caching headers correctly in the first place on server side. Stealing the header info from Best way to disable client caching, a .htaccess file like this should work:

<Files myfile.txt>
FileETag None
<IfModule mod_headers.c>
Header unset ETag
Header set Cache-Control "store, no-cache, must-revalidate, post-check=0, pre-check=0"
Header set Pragma "no-cache"
Header set Expires "Sun, 19 Nov 1978 05:00:00 GMT"
</IfModule>
</Files>

Upvotes: 28

Job
Job

Reputation: 55

Just put

<meta http-equiv="expires" content="0">

Into the head section of your target page and check again

Upvotes: 3

mkk
mkk

Reputation: 7693

You can solve your problem on server level. Set the special expiration date for txt resources (or that particular one) that fit to your requirements. If you use apache you can read about mod_expiry for apache here

Upvotes: 0

Puggan Se
Puggan Se

Reputation: 5846

The best way is to tell apache/(web server) to tell browser not allow caching of that file, if you don't have controll over that server, you could avoid cache by alter the parameters send to it, just add some numbers behind ?, for exemple the time when you created the link, this makes each url diferent, so the browser going to ignore the cache, but all links to the same file, as long as the server ignore the extra parameter. in php:

echo "<a href='http://example.com/myfile.txt?" . time() . "'>View!</a>"

Upvotes: 2

Raptor
Raptor

Reputation: 54212

Add a random number after the hyper link, such as <a href="http://example.com/myfile.txt?rand=12312321321">View!</a>

Generate a new random number each time the page loads.

Upvotes: 0

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