Preventing Flex application caching in browser (multiple modules)

Question

I have a Flex application with multiple modules.

When I redeploy the application I was finding that modules (which are deployed as separate swf files) were being cached in the browser and the new versions weren't being loaded.

So i tried the age old trick of adding ?version=xxx to all the modules when they are loaded. The value xxx is a global parameter which is actually stored in the host html page:

var moduleSection:ModuleLoaderSection;
moduleSection = new ModuleLoaderSection();
moduleSection.visible = false;
moduleSection.moduleName = moduleName + "?version=" + MySite.masterVersion;

In addition I needed to add ?version=xxx to the main .swf that was being loaded. Since this is done by HTML I had to do this by modifying my AC_OETags.js file as below :

function AC_FL_RunContent(){
  var ret = 
    AC_GetArgs
    (  arguments, ".swf?mv=" + getMasterVersion(), "movie", "clsid:d27cdb6e-ae6d-11cf-96b8-444553540000"
     , "application/x-shockwave-flash"
    );
  AC_Generateobj(ret.objAttrs, ret.params, ret.embedAttrs);
}

This is all fine and works great. I just have a hard time believing that Adobe doesn't already have a way to handle this. Given that Flex is being targeted to design modular applications for business I find it especially surprising.

What do other people do? I need to make sure my application reloads correctly even if someone has once per session selected for their 'browser cache checking policy'.

Answer 1

The caching is not done by Flash Player but by the browser, so it's out of Adobe's control. I think you have found a workable solution. If I want to avoid caching I usually append a random number on the URL.

Answer 2

Hi Simon,

Great post! Sorry if I'm slow but got few questions: 1) Where do you declare ModuleLoaderSection? 2) in AC_FL_RunContent(), how do you define the getMasterVersion()? Thanks

Answer 3

post withdrawn by Clowe

Answer 4

What I have done is checksum the SWF file and then add that to its url. Stays the same until the file is rebuilt/redeployed. Handled automagically by a few lines of server-side PHP script

Answer 5

Hi, Could you please send me the sample code. I am in deperate need of preventing cache problem. I would appreciate a sample code. thanks.

Answer 6

I had a similar problem, and ended up putting the SWF files in a sub-directory named as the build number. This meant that the URL to the SWF files pointed to a different location each time.

Ideally this should be catered for by the platform, but no joy there. But this works perfectly for us, and integrates very easily into our automated builds with Hudson - no complaints so far.

Answer 7

Looks like i get the accepted answer myself :-(

Answer 8

Hi Simon or anyone,

How does this apply to RSL? When we load the swf and module using ?verion=xxx approach, does it guarantee to load the non-cache RSL as well?

Appreciate the help.

Answer 9

hi Simon or anyone this solution is great. but I am getting another problem. I am using IE6 & FF 3.6 and browsers are trying to download swf file second time when user tries to login. any elegant solution than this java script?

thanks

Answer 10

hi Harsh here is sample.

---

function AC_FL_RunContent(){ var ret = AC_GetArgs ( arguments, ".swf?ts=" + getTS(), "movie", "clsid:d27cdb6e-ae6d-11cf-96b8-444553540000" , "application/x-shockwave-flash" ); AC_Generateobj(ret.objAttrs, ret.params, ret.embedAttrs); }

function getTS() { var ts = new Date().getTime(); return ts;

}

AC_OETags.js is file and it exists html-template several places. but as my posting said, I am facing another type of problem.

Answer 11

Flex says:

http://www.adobe.com/livedocs/flex/2/docs/wwhelp/wwhimpl/common/html/wwhelp.htm?context=LiveDocs_Parts&file=00001388.html

Answer 12

Stuart, your solution sounds compelling. Will you please provide more details about how you've set up Hudson to do the build so that it automatically creates the SWF in the right directory and the HTML file knows where to get the SWF?