Follow symlinks when building bundle

[jcheng5]

I have NOT tested this on Windows, only Mac. Please nobody merge until I've tested.

Intent

Fixes #414. When building a bundle, follow symlinks. This allows apps to include directories that might live somewhere else for deduplication/centralization reasons.

Type of Change

• [x] Bug Fix
• [ ] New Feature
• [ ] Breaking Change

Approach

os.walk takes a followlinks argument that defaults to False. I simply set this to True. Note that from googling, os.walk doesn't check for circular references--I'm happy to add that if we think it's important.

Automated Tests

TODO

Directions for Reviewers

Create two sibling directories, one called data and one called shinytest.

shinytest/app.py:

from pathlib import Path
from shiny.express import input, ui

msg_path = Path(__file__).parent / "data/message.txt"

with open(msg_path) as f:
    f.read()

data/message.txt:

Hello, world!

Then, from within the shinytest directory, run ln -s ../data data.

Deploy from within the shinytest directory as usual, and see if it crashes on startup or the message correctly appears instead.

Checklist

• [ ] I have updated CHANGELOG.md to cover notable changes.
• [ ] I have updated all related GitHub issues to reflect their current state.

[github-actions[bot]]

☂️ Python Coverage

current status: ✅

Overall Coverage

Lines	Covered	Coverage	Threshold	Status
4409	3134	71%	0%	🟢

New Files

No new covered files...

Modified Files

File	Coverage	Status
rsconnect/bundle.py	79%	🟢
TOTAL	79%	🟢

updated for commit: aa3a496 by action🐍

[jcheng5]

I played around with Windows and it's pretty weird.

The good news is symlinks work fine, the command is mklink and Python handles them just fine. I haven't tried with git but it's supposed to work; there's a core.symlinks option that defaults to true.

They're not supported on FAT filesystems but that's probably OK for our purposes.

However, by default, you don't have permissions to call mklink unless you are at an Administrator prompt. That's true even if you have write permissions to the directory where you're trying to create the link--it's the creation of a symlink that's considered a privileged operation. You can put Windows into developer mode (doesn't even require a restart) and then anyone can call mklink.

[nealrichardson]

I played around with Windows and it's pretty weird.

So true 😆

Weird but this is fine to merge, @jcheng5? Even if you're not an admin, you can still follow symlinks, right?