You may use either the ZipFile class (see JSAPI.chm documentation, under license). You must get the URI and save it as a file.zip (for instance in a temporary folder), then you use the ZipFile class on that file.
Or, most of all if the compressed file is made with specific compression algorithms or options, I recommend using 7-ZIP free tool on your server (if possible for you to get such tool allowed, depending on the hosting On Cloud/On Premise). In that case, it must be allowed in serverConf.xml if your Adobe Campaign instance has a recent build version. You can either use an execCommand method (JSAPI again) or in a workflow, the External task activity to uncompress the file.