Minifing js files with w3 total cache and expiring the combined file [closed]

Question

I'd like to clarify several details about how w3 total cache works.

I'm using w3 total cache to combine multiple js files into one. I'm also setting expires headers from the browser tab to twenty days. Garbage collection interval is set to one day.

When the combined file is rebuilt due to garbage collection will the combined file name change if the js files haven't been changed? I guess it will not change as otherwise users won't be able to use the cached one.

If I modify one of the files will w3tc automatically detect it or do I need to clear the minify cache?

To sum up I am interested in which cases the combined file name changes and do I have to worry about clients using older version do to expires headers and how w3tc manages it.

Answer 1

Plugin is way too complex for me to follow code. :(

I can say that in practice after emptying minify cache both CSS and JS concatenated files are rebuilt with same name, using same numerical id.

So my educated guess would be that numerical id is tied to file contents, rather than being random or timestamp-ish.

Anyway it is probably best to contact plugin's developer and get first hand info. He is registered here ( Frederick Townes ), but not very active - so email or official WP forums are better for that.