[Xerte-dev] Browser caching and problems it causes with each update

[Tom Reijnders]

Hi,

I've had several instances where we had a sudden increase of support 
calls after installing an update of XOT (i.e. from 3.0 to 3.1)

Most of those were due to caching issues. i.e. new modelfiles were used 
against a previous cached version of xenith.js

There are several solutions to this:

1. At a timestamp in the url that loads xenth.js , ie 
src="xenith.js?_=<?php echo $timestamp;?>" or similar

The drawback of course is that xenith.js (and similar files) are not 
cached anymore, increasing the time needed to load an LO

2. Add a version to the filename of xenith.js, i.e. everytime something 
changes in xenith.js, change the version.

This is the approach used by a lot of javascript libraries, cf. jQuery. 
But it it's painfull, and errorprone (or we have to have a build process).

3. An interesting variation could be the combination of 1. and 2.

We have a version string maintained in the file version.txt in the root 
folder of the installation. This file is automatically updated when 
publishing zips for the community websites. We could add 
?version='<contents of version.txt>' to all the files we want to reload 
after a new release, such as xenith.js

Tests show that this works fine ans as expected. I would like to 
implement 3.

Any objections, remarks, other solutions?

Tom


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Tom Reijnders
TOR Informatica
Chopinlaan 27
5242HM Rosmalen
Tel: 073 5226191
Fax: 073 5226196