viv

viv isn't venv

---

Python is a great choice to quickly prototype or accomplish small tasks in scripts. However, leveraging it's vast ecosystem can be tedious for one-off or rarely used scripts. This is were viv comes in handy.

Viv is a standalone dependency-free venv creator. It is meant to be invoked in any script that has third-party dependencies, prior to loading of any of the external modules.

These venvs can be identified by name or by their specification. In any case they will be re-used across scripts (and generated on-demand, if needed).

Importantly, viv will also remove your user site directory. (view with: python -m 'import site;print(site.USER_SITE)').

Setup

Run the below command to install viv.

python3 <(curl -fsSL gh.dayl.in/viv/viv.py) manage install -r v23.5a1

To access viv from within scripts you should add it's location to your PYTHONPATH. By default viv will be installed to $XDG_DATA_HOME/viv or ~/.local/share/viv you can customize this with --src.

export PYTHONPATH="$PYTHONPATH:$HOME/.local/share/viv"

Advanced users may recognize that principally, the module just needs to be recognized at run time and the single script at ./src/viv/viv.py can be invoked directly for the CLI. How you accomplish these options is ultimately up to you but the above instructions can get you started.

Pypi (Not Recommended)

pip install viv

Why is this not recommended? Mainly, because viv is all about hacking your sys.path. Placing it in it's own virtual environment or installing in a user site directory may complicate this endeavor.

Usage

In any python script with external dependencies you can add this line, to automate vivenv creation and installation of dependencies.

__import__("viv").use("click")

To remove all vivenvs you can use the below command:

viv remove $(viv list -q)

Standalone Viv

Supposing you want to increase the portability of your script while still employing the principles of viv.

The below function can be freely pasted at the top of your scripts and requires no modification of your PYTHONPATH or import of additional modules (including downloading/installing viv).

It can be auto-generated with for example: viv freeze <spec> --standalone.

The only part necessary to modify if copied verbatim from below is the call to _viv_use.

Output of viv freeze rich --standalone:

# <<<<< auto-generated by daylinmorgan/viv (v22.12a3-35-g0d0c66d-dev)
# fmt: off
def _viv_use(*pkgs: str, track_exe: bool = False, name: str = "") -> None:                                    # noqa
    i,s,m,e,spec=__import__,str,map,lambda x: True if x else False,[*pkgs]                                    # noqa
    if not {*m(type,pkgs)}=={s}: raise ValueError(f"spec: {pkgs} is invalid")                                 # noqa
    ge,sys,P,ew=i("os").getenv,i("sys"),i("pathlib").Path,i("sys").stderr.write                               # noqa
    (cache:=(P(ge("XDG_CACHE_HOME",P.home()/".cache"))/"viv"/"venvs")).mkdir(parents=True,exist_ok=True)      # noqa
    ((sha256:=i("hashlib").sha256()).update((s(spec)+                                                         # noqa
     (((exe:=("N/A",s(P(i("sys").executable).resolve()))[e(track_exe)])))).encode()))                         # noqa
    if (env:=cache/(name if name else (_id:=sha256.hexdigest()))) not in cache.glob("*/") or ge("VIV_FORCE"): # noqa
        v=e(ge("VIV_VERBOSE"));ew(f"generating new vivenv -> {env.name}\n")                                   # noqa
        i("venv").EnvBuilder(with_pip=True,clear=True).create(env)                                            # noqa
        with (env/"pip.conf").open("w") as f:f.write("[global]\ndisable-pip-version-check=true")              # noqa
        if (p:=i("subprocess").run([env/"bin"/"pip","install","--force-reinstall",*spec],text=True,           # noqa
            stdout=(-1,None)[v],stderr=(-2,None)[v])).returncode!=0:                                          # noqa
            if env.is_dir():i("shutil").rmtree(env)                                                           # noqa
            ew(f"pip had non zero exit ({p.returncode})\n{p.stdout}\n");sys.exit(p.returncode)                # noqa
        with (env/"viv-info.json").open("w") as f:                                                            # noqa
            i("json").dump({"created":s(i("datetime").datetime.today()),"id":_id,"spec":spec,"exe":exe},f)    # noqa
    sys.path = [p for p in (*sys.path,s(*(env/"lib").glob("py*/si*"))) if p!=i("site").USER_SITE]             # noqa
_viv_use("markdown-it-py==2.2.0", "mdurl==0.1.2", "Pygments==2.14.0", "rich==13.3.2")                         # noqa
# fmt: on
# >>>>> code golfed with <3

Alternatives

pip-run

pip-run (10.0.5)
├── autocommand (2.2.2)
├── jaraco-context (4.3.0)
├── jaraco-functools (3.6.0)
│   └── more-itertools (9.1.0)
├── jaraco-text (3.11.1)
│   ├── autocommand (2.2.2)
│   ├── inflect (6.0.2)
│   │   └── pydantic>=1.9.1 (1.10.5)
│   │       └── typing-extensions>=4.2.0 (4.5.0)
│   ├── jaraco-context>=4.1 (4.3.0)
│   ├── jaraco-functools (3.6.0)
│   │   └── more-itertools (9.1.0)
│   └── more-itertools (9.1.0)
├── more-itertools>=8.3 (9.1.0)
├── packaging (23.0)
├── path>=15.1 (16.6.0)
├── pip>=19.3 (23.0.1)
└── platformdirs (3.1.0)

pipx

pipx (1.1.0)
├── argcomplete>=1.9.4 (2.1.1)
├── packaging>=20.0 (23.0)
└── userpath>=1.6.0 (1.8.0)
    └── click (8.1.3)