One issue you might have with that is that your text file will be on the server, so the js running in your browser won't find it. If that's not it, though, perhaps you could expand on "could not make that successful".
Is there a reason why having the .php extension is an issue? Maybe a
.htaccess rewrite rule could get around the problem if it's just that you don't want to have users type it in, but if it's the default / index / home page as configured, normally the server can be told to search for the appropriate extension.