Jereme,
I believe that for an upload merely using the Selenium API should work (even in the Grid). Please see the javadocs of org.openqa.selenium.remote.RemoteWebDriver#setFileDetector
In this case you would need to use LocalFileDetector and that should do the trick.
Alternatively you can set this via org.openqa.selenium.remote.RemoteWebElement#setFileDetector
A RemoteWebELement is an implementation of WebElement interface and so you should be able to cast it safely I believe.
Usually a volume is required ONLY when trying to download something from a browser onto the node which then needs to be accessible to the test.
Thanks & Regards
Krishnan Mahadevan
"All the desirable things in life are either illegal, expensive, fattening or in love with someone else!"
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