fix(setup): remove sudo for pip

[kenji-miyake]

Description

We've been using sudo for pip because, as written in ~/.profile, $HOME/.local/bin isn't in the $PATH right after OS installation.

# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/.local/bin" ] ; then
    PATH="$HOME/.local/bin:$PATH"
fi

However, using sudo for pip isn't recommended.

$ sudo pip install clang-format
[sudo] password for kenji: 
Requirement already satisfied: clang-format in /usr/local/lib/python3.10/dist-packages (14.0.1)
WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv

As I thought sudo can be removed if I add export PATH="$HOME/.local/bin:$PATH" in the setup script, I changed so.

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[kenji-miyake]

Since I haven't tested this well, I'll mark this as a draft.

[esteve]

@kenji-miyake alternatively, what do you think of virtualenv? virtualenvwrapper lets you have multiple versions of Python workspaces and are stored in a central place (https://virtualenvwrapper.readthedocs.io/en/latest/)

[kenji-miyake]

@esteve I think it's good! But there are some problems:

• I'm not familiar with it.
• I'm not sure if it works well with ROS 2.

Do you know about it?

[esteve]

@kenji-miyake yeah, we used virtualenv quite a lot during the development of ROS2 at Open Robotics. It's in the documentation as one of the options for working with Python packages with ROS2 https://docs.ros.org/en/galactic/How-To-Guides/Using-Python-Packages.html#installing-via-a-virtual-environment

[kenji-miyake]

@esteve Thank you for the link. 🙏

Seeing this, after the user run source ./venv/bin/activate, it seems the same as the normal user mode of pip.

If so, I guess this PR also works with virtualenv. Am I right? 🤔

[esteve]

@kenji-miyake yes, it should work the same. But this was just to ask you if you think it's a good idea, perhaps we don't need to add this to the development process. One nice thing is that any dependencies we install are in the virtualenv, so if we want to remove all the dependencies with installed, it's as easy as removing the virualenv

[kenji-miyake]

@esteve I see. 👍
Do you think it's good to merge this now (even though it may break something) and will observe it for a while? (And will fix bugs if issues are reported.)
If it's okay, I'll make this ready for review.

Currently, it's not good because it obviously won't work with virtualenv.

[esteve]

@kenji-miyake I think it should be ok to merge this 👍

[kenji-miyake]

Okay, then I'll set reviewers from TIER IV who might be familiar with this issue!

[yukkysaito]

LGTM

[wep21]

LGTM