Today I’m going to talk about a special builtin variable __file__ as it is implemented in the RevitPythonShell. This feature is only available to external scripts
and RpsAddins. This is similar to how __file__ is normally defined for Python: It is not defined in the REPL.
Simply put: __file__ contains the path to the current file being run.
With external scripts, this is a path to a python script. With RpsAddins, it is the path to the addin’s DLL, a path separator, and the name of the script (e.g. C:\Program Files (x86)\MyAddin\MyAddin.dll\helloworld.py).
Suppose you have deployed some scripts to another computer. Suppose those scripts rely on other files - a database, maybe, or icons, pictures, anything really. If you keep referencing these files as C:\Users\Gareth\AwesomeScripts\all_my_data.sqlite you are going to run into difficulties on a computer that doesn’t belong to Gareth. Meg’s computer won’t know how to find the database! And she is going to complain to Meg and meg is going to complain to her boss and her boss is going to complain to your boss and your boss is going to go get coffee, lock himself up in his office and brood for a very long time. Then, he’s going to send someone to tell you to come to his office ASAP. Now!
You don’t want that to happen! That is why you’re going to make sure that all file references are relative to the installation of your external scripts / RpsAddins. And unless you have a priori knowledge of the folder name you’re installing to, well, I’ve got your back:
def get_folder():
import os
# assume external script
folder = os.path.dirname(__file__)
if folder.lower().endswith('.dll'):
# nope - RpsAddin
folder = os.path.dirname(folder)
return folder