zulip/scripts/lib/create-production-venv

#!/usr/bin/env python3

import os
import argparse
from os.path import dirname, abspath
import sys

ZULIP_PATH = dirname(dirname(dirname(abspath(__file__))))
if ZULIP_PATH not in sys.path:
    sys.path.append(ZULIP_PATH)

from scripts.lib.zulip_tools import run
from scripts.lib.setup_venv import setup_virtualenv, VENV_DEPENDENCIES

parser = argparse.ArgumentParser(description="Create a production virtualenv with caching")
parser.add_argument("deploy_path")
args = parser.parse_args()

# install dependencies for setting up the virtualenv
run(["apt-get", "-y", "install"] + VENV_DEPENDENCIES)

python_version = sys.version_info[0]

# Set the current working directory to the Zulip checkout, so the api/
# relative path in requirements/common.txt works.
os.chdir(ZULIP_PATH)

venv_name = "zulip-venv" if sys.version_info[0] == 2 else "zulip-py3-venv"
cached_venv_path = setup_virtualenv(
    os.path.join(args.deploy_path, venv_name),
    os.path.join(ZULIP_PATH, "requirements", "prod_lock.txt"),
    virtualenv_args=['-p', 'python{}'.format(python_version)])

current_venv_path = os.path.join(args.deploy_path, 'zulip-current-venv')
run(['ln', '-nsf', venv_name, current_venv_path])
# Now the virtualenv has been activated