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Build Command Line Tools with Python Poetry

Jonathan Bowman on August 04, 2020

Poetry is a robust and convenient tool for building Python projects. The article Getting Started with Python Poetry demonstrated this in simple ter...

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Michael Klengel • Feb 3 '21 • Edited

Great article but I have a problem with the scripting part in pyproject.toml:

[tool.poetry.scripts]
greet = "greet.location:cli"

The location of my project folder contains a space and this results in an error:

(.venv) ➜  pygreet greet
zsh: /Volumes/Macintosh SR0/Users/mklengel/Development/pygreet/.venv/bin/greet: bad interpreter: /Volumes/Macintosh: no such file or directory

The question is how to improve the scripting part in pyproject.toml.

Regards
Michael

Jonathan Bowman • Feb 4 '21

Interesting. You are right; that space in Macintosh SR0 is causing problems. What version of poetry are you using, and how did you install it?

It looks like your issue was supposed to have been resolved by Poetry Issue 1774, which is why I ask.

Michael Klengel • Feb 4 '21 • Edited

Hi Jonathan,

I've detected another bug in conjunction with a space in the path:
Poetry Issue 3630

I've created a new issue:
Poetry Issue 3643

Seems to be insufficient automated testing during the development of poetry.

➜  ~ poetry --version
Poetry version 1.1.4

Jonathan Bowman • Feb 4 '21

Good job finding the first issue, and logging the other! Are both resolved by #3631, or just the first?

Michael Klengel • Feb 4 '21 • Edited

Thx - I do my best to learn python so currently I can only help with bug reports :-)
#3631 doesn’t solve the shebang problem, therefore the bug report.

Michael Klengel • Feb 4 '21 • Edited

Hi Jonathan,

I saw your comment on GitHub. May be I have to check the consequences of renaming the mount paths on my Mac. Should be the practical solution of the problem.

Jonathan Bowman • Feb 4 '21

What about a symlink? ln -s /Volumes/Macintosh\ SR0/ /HD or something similar? I am not a Mac expert; just pondering.

Michael Klengel • Feb 4 '21

The path is already linked:

(.venv) ➜  ~ pwd
/Users/mklengel
(.venv) ➜  ~ ls -l Development 
lrwxr-xr-x  1 mklengel  staff  49 Jan 15 22:03 Development -> /Volumes/Macintosh SR0/Users/mklengel/Development
(.venv) ➜  ~ cd Development/pygreet 
(.venv) ➜  pygreet pwd
/Users/mklengel/Development/pygreet
(.venv) ➜  pygreet poetry shell
Virtual environment already activated: /Volumes/Macintosh SR0/Users/mklengel/Development/pygreet/.venv

poetry "sees" the path but ignores the symbolic link.

Jonathan Bowman • Feb 5 '21

Michael, what do you think of these steps? Are they a decent, at least temporary, workaround?

sudo ln -s '/Volumes/Macintosh SR0/Users' /homeward
cd /homeward/mklengel/Development/pygreet/
rm -rf .venv
poetry config virtualenvs.in-project false
poetry config virtualenvs.path /homeward/mklengel/Development/.poetryvenv
poetry install

You can adapt names, paths, etc to your liking.

In summary, the above creates a symlink to your users directory (call it homeward or home or whatever you like), then, instead of storing the virtual environment in .venv in the project directory, sets it in poetry's global config to be in a directory of your choosing. Remove the existing .venv in the project, reinstall the project, and it should use the new virtual environment without spaces.

What do you think?

Michael Klengel • Feb 5 '21

Hi Jonathan,

thx for your suggestion. The symbolic path exists already:

➜  pygreet ls -ld $HOME/Development/pygreet
drwxr-xr-x  8 mklengel  staff  256  5 Feb 13:38 /Users/mklengel/Development/pygreet

Create the virtualenv inside the project's root directory leads to:

➜  pygreet head -1 .venv/bin/greet
#!/Volumes/Macintosh SR0/Users/mklengel/Development/pygreet/.venv/bin/python

Using the default virtualenv folder looks much better:

➜  pygreet poetry config virtualenvs.in-project false

➜  pygreet poetry config --list
cache-dir = "/Users/mklengel/Library/Caches/pypoetry"
experimental.new-installer = true
installer.parallel = true
virtualenvs.create = true
virtualenvs.in-project = false
virtualenvs.path = "{cache-dir}/virtualenvs"  # /Users/mklengel/Library/Caches/pypoetry/virtualenvs

➜  pygreet poetry install
Creating virtualenv greet-hlYPq_3g-py3.9 in /Users/mklengel/Library/Caches/pypoetry/virtualenvs
Installing dependencies from lock file

Package operations: 24 installs, 0 updates, 0 removals

  • Installing pyparsing (2.4.7)
  • Installing six (1.15.0)
  • Installing appdirs (1.4.4)
  • Installing attrs (20.3.0)
  • Installing click (7.1.2)
  • Installing mccabe (0.6.1)
  • Installing more-itertools (8.6.0)
  • Installing mypy-extensions (0.4.3)
  • Installing packaging (20.9)
  • Installing pathspec (0.8.1)
  • Installing pluggy (0.13.1)
  • Installing py (1.10.0)
  • Installing pycodestyle (2.6.0)
  • Installing pyflakes (2.2.0)
  • Installing python-dateutil (2.8.1)
  • Installing regex (2020.11.13)
  • Installing toml (0.10.2)
  • Installing typed-ast (1.4.2)
  • Installing typing-extensions (3.7.4.3)
  • Installing wcwidth (0.2.5)
  • Installing arrow (0.17.0)
  • Installing black (20.8b1)
  • Installing flake8 (3.8.4)
  • Installing pytest (5.4.3)

Installing the current project: greet (0.1.0)
➜  pygreet head -1 ~/Library/Caches/pypoetry/virtualenvs/greet-hlYPq_3g-py3.9/bin/greet
#!/Users/mklengel/Library/Caches/pypoetry/virtualenvs/greet-hlYPq_3g-py3.9/bin/python

➜  pygreet poetry shell
Spawning shell within /Users/mklengel/Library/Caches/pypoetry/virtualenvs/greet-hlYPq_3g-py3.9

➜  pygreet . /Users/mklengel/Library/Caches/pypoetry/virtualenvs/greet-hlYPq_3g-py3.9/bin/activate

(greet-hlYPq_3g-py3.9) ➜  pygreet greet Africa/Addis_Ababa
Hello, Addis Ababa! The time is 4:50 pm.

So may be this is the bug in poetry: the shebang line is not the symbolic one if the virtualenv folder is in the project's root directory.