Hướng dẫn python3 venv - python3 venv
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1.Giới thiệu Virtual Environment trong Python2. Cài đặt và sử dụng Virtual environmentpython là môi trường ảo. Cũng giống như máy ảo (Virtual Machine), Virtual Environment thiết lập một môi trường ảo, cho phép bạn thoải mái thực hiện cài đặt rồi xóa, cài đặt các phiên bản khác nhau với các packages của Python mà không sợ làm ảnh hưởng đến những dự án đang có sẵn. 2. Cài đặt và sử dụng Virtual environment2.1 Cài đặt virtualenv 2.2 Tạo môi trường ảovirtualenv. 2.1 Cài đặt virtualenvvirtualenv2.2 Tạo môi trường ảo 2.2 Tạo môi trường ảo2.3 Khởi động môi trường ảo 2.4 Tắt môi trường ảopython_env là tên đường dẫn chứa Virtual Environment cho dự án của bạn. 2.3 Khởi động môi trường ảo2.4 Tắt môi trường ảo 2.5 Xuất các package đã cài đặt(python_env) 2.4 Tắt môi trường ảo2.5 Xuất các package đã cài đặt 2.5 Xuất các package đã cài đặt2.6 Nhập các package
2.6 Nhập các packageVirtual Environment trong python là môi trường ảo. Cũng giống như máy ảo (Virtual Machine), Virtual Environment thiết lập một môi trường ảo, cho phép bạn thoải mái thực hiện cài đặt rồi xóa, cài đặt các phiên bản khác nhau với các packages của Python mà không sợ làm ảnh hưởng đến những dự án đang có sẵn.
Có hai công cụ chính được sử dụng để tạo môi trường ảo: • virtualenv là công cụ tiêu chuẩn trong nhiều năm, có thể được sử dụng với cả Python 2 và 3. • venv (pyvenv) được thêm vào thư viện chuẩn trong Python 3.3. Trong bài viết này chúng ta sẽ sử dụng virtualenv. Để cài đặt virtualenv chúng ta sử dụng lệnh sau: Tiếp đến chúng ta sử dụng lệnh Trong đó python_env là tên đường dẫn chứa Virtual Environment cho dự án của bạn. Mới trong phiên bản 3.3. Đã thay đổi trong phiên bản 3.4: Đã thêm tham số Đã thay đổi trong phiên bản 3.6: Đã thêm tham số Đã thay đổi trong phiên bản 3.9: Đã thêm tham số Một ví dụ về việc mở rộng ____ 72¶PEP 405 for more background on Python virtual environments. Tập lệnh sau đây cho thấy cách mở rộng import os import os.path from subprocess import Popen, PIPE import sys from threading import Thread from urllib.parse import urlparse from urllib.request import urlretrieve import venv class ExtendedEnvBuilder(venv.EnvBuilder): """ This builder installs setuptools and pip so that you can pip or easy_install other packages into the created virtual environment. :param nodist: If true, setuptools and pip are not installed into the created virtual environment. :param nopip: If true, pip is not installed into the created virtual environment. :param progress: If setuptools or pip are installed, the progress of the installation can be monitored by passing a progress callable. If specified, it is called with two arguments: a string indicating some progress, and a context indicating where the string is coming from. The context argument can have one of three values: 'main', indicating that it is called from virtualize() itself, and 'stdout' and 'stderr', which are obtained by reading lines from the output streams of a subprocess which is used to install the app. If a callable is not specified, default progress information is output to sys.stderr. """ def __init__(self, *args, **kwargs): self.nodist = kwargs.pop('nodist', False) self.nopip = kwargs.pop('nopip', False) self.progress = kwargs.pop('progress', None) self.verbose = kwargs.pop('verbose', False) super().__init__(*args, **kwargs) def post_setup(self, context): """ Set up any packages which need to be pre-installed into the virtual environment being created. :param context: The information for the virtual environment creation request being processed. """ os.environ['VIRTUAL_ENV'] = context.env_dir if not self.nodist: self.install_setuptools(context) # Can't install pip without setuptools if not self.nopip and not self.nodist: self.install_pip(context) def reader(self, stream, context): """ Read lines from a subprocess' output stream and either pass to a progress callable (if specified) or write progress information to sys.stderr. """ progress = self.progress while True: s = stream.readline() if not s: break if progress is not None: progress(s, context) else: if not self.verbose: sys.stderr.write('.') else: sys.stderr.write(s.decode('utf-8')) sys.stderr.flush() stream.close() def install_script(self, context, name, url): _, _, path, _, _, _ = urlparse(url) fn = os.path.split(path)[-1] binpath = context.bin_path distpath = os.path.join(binpath, fn) # Download script into the virtual environment's binaries folder urlretrieve(url, distpath) progress = self.progress if self.verbose: term = '\n' else: term = '' if progress is not None: progress('Installing %s ...%s' % (name, term), 'main') else: sys.stderr.write('Installing %s ...%s' % (name, term)) sys.stderr.flush() # Install in the virtual environment args = [context.env_exe, fn] p = Popen(args, stdout=PIPE, stderr=PIPE, cwd=binpath) t1 = Thread(target=self.reader, args=(p.stdout, 'stdout')) t1.start() t2 = Thread(target=self.reader, args=(p.stderr, 'stderr')) t2.start() p.wait() t1.join() t2.join() if progress is not None: progress('done.', 'main') else: sys.stderr.write('done.\n') # Clean up - no longer needed os.unlink(distpath) def install_setuptools(self, context): """ Install setuptools in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bitbucket.org/pypa/setuptools/downloads/ez_setup.py' self.install_script(context, 'setuptools', url) # clear up the setuptools archive which gets downloaded pred = lambda o: o.startswith('setuptools-') and o.endswith('.tar.gz') files = filter(pred, os.listdir(context.bin_path)) for f in files: f = os.path.join(context.bin_path, f) os.unlink(f) def install_pip(self, context): """ Install pip in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bootstrap.pypa.io/get-pip.py' self.install_script(context, 'pip', url) def main(args=None): compatible = True if sys.version_info < (3, 3): compatible = False elif not hasattr(sys, 'base_prefix'): compatible = False if not compatible: raise ValueError('This script is only for use with ' 'Python 3.3 or later') else: import argparse parser = argparse.ArgumentParser(prog=__name__, description='Creates virtual Python ' 'environments in one or ' 'more target ' 'directories.') parser.add_argument('dirs', metavar='ENV_DIR', nargs='+', help='A directory in which to create the ' 'virtual environment.') parser.add_argument('--no-setuptools', default=False, action='store_true', dest='nodist', help="Don't install setuptools or pip in the " "virtual environment.") parser.add_argument('--no-pip', default=False, action='store_true', dest='nopip', help="Don't install pip in the virtual " "environment.") parser.add_argument('--system-site-packages', default=False, action='store_true', dest='system_site', help='Give the virtual environment access to the ' 'system site-packages dir.') if os.name == 'nt': use_symlinks = False else: use_symlinks = True parser.add_argument('--symlinks', default=use_symlinks, action='store_true', dest='symlinks', help='Try to use symlinks rather than copies, ' 'when symlinks are not the default for ' 'the platform.') parser.add_argument('--clear', default=False, action='store_true', dest='clear', help='Delete the contents of the ' 'virtual environment ' 'directory if it already ' 'exists, before virtual ' 'environment creation.') parser.add_argument('--upgrade', default=False, action='store_true', dest='upgrade', help='Upgrade the virtual ' 'environment directory to ' 'use this version of ' 'Python, assuming Python ' 'has been upgraded ' 'in-place.') parser.add_argument('--verbose', default=False, action='store_true', dest='verbose', help='Display the output ' 'from the scripts which ' 'install setuptools and pip.') options = parser.parse_args(args) if options.upgrade and options.clear: raise ValueError('you cannot supply --upgrade and --clear together.') builder = ExtendedEnvBuilder(system_site_packages=options.system_site, clear=options.clear, symlinks=options.symlinks, upgrade=options.upgrade, nodist=options.nodist, nopip=options.nopip, verbose=options.verbose) for d in options.dirs: builder.create(d) if __name__ == '__main__': rc = 1 try: main() rc = 0 except Exception as e: print('Error: %s' % e, file=sys.stderr) sys.exit(rc)WebAssembly platforms for more information. Kịch bản này cũng có sẵn để tải xuống trực tuyến.Mã nguồn: lib/venv/virtual environments is done by executing the command c:\>c:\Python35\python -m venv c:\path\to\myenv3: python3 -m venv /path/to/new/virtual/environment Mô -đun c:\>c:\Python35\python -m venv c:\path\to\myenv3 hỗ trợ tạo ra các môi trường ảo nhẹ, mỗi bộ có bộ gói Python độc lập riêng được cài đặt trong các thư mục c:\>c:\Python35\python -m venv c:\path\to\myenv4 của họ. Một môi trường ảo được tạo ra trên đầu cài đặt Python hiện có, được gọi là môi trường ảo, cơ sở của Python, và có thể được phân lập từ các gói trong môi trường cơ sở, do đó, chỉ có những gói được cài đặt rõ ràng trong môi trường ảo. Đã không dùng nữa vì phiên bản 3.6: c:\>python -m venv c:\path\to\myenv5 was the recommended tool for creating virtual environments for Python 3.3 and 3.4, and is deprecated in Python 3.6. Đã thay đổi trong phiên bản 3.5: Việc sử dụng c:\>c:\Python35\python -m venv c:\path\to\myenv3 is now recommended for creating virtual environments. Trên Windows, gọi lệnh c:\>c:\Python35\python -m venv c:\path\to\myenv3 như sau: c:\>c:\Python35\python -m venv c:\path\to\myenv Ngoài ra, nếu bạn đã cấu hình các biến c:\>python -m venv c:\path\to\myenv8 và c:\>python -m venv c:\path\to\myenv9 cho cài đặt Python của bạn:Python installation: c:\>python -m venv c:\path\to\myenv Lệnh, nếu chạy với usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.0, sẽ hiển thị các tùy chọn có sẵn: usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory. Đã thay đổi trong phiên bản 3.9: Thêm tùy chọn usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.1 option to upgrade pip + setuptools to the latest on PyPI Đã thay đổi trong phiên bản 3.4: Cài đặt PIP theo mặc định, đã thêm các tùy chọn usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.2 and usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.3 options Đã thay đổi trong phiên bản 3.4: Trong các phiên bản trước, nếu thư mục đích đã tồn tại, lỗi đã được nêu ra, trừ khi tùy chọn usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.4 or usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.5 option was provided. Ghi chú Mặc dù các liên kết symlink được hỗ trợ trên Windows, nhưng chúng không được khuyến khích. Đặc biệt lưu ý là việc nhấp đúp vào usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.6 trong File Explorer sẽ giải quyết Symlink một cách háo hức và bỏ qua môi trường ảo. Ghi chú Mặc dù các liên kết symlink được hỗ trợ trên Windows, nhưng chúng không được khuyến khích. Đặc biệt lưu ý là việc nhấp đúp vào usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.6 trong File Explorer sẽ giải quyết Symlink một cách háo hức và bỏ qua môi trường ảo. Trên Microsoft Windows, có thể cần phải bật tập lệnh usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.7 bằng cách đặt chính sách thực thi cho người dùng. Bạn có thể làm điều này bằng cách ban hành lệnh PowerShell sau: PS C:> Set -ExecutionPolicy -executpolicy RemoteSign -scope CurrentUser Xem về chính sách thực thi để biết thêm thông tin. Tệp c:\>c:\Python35\python -m venv c:\path\to\myenv8 được tạo cũng bao gồm khóa usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.9, được đặt thành def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)0 nếu c:\>c:\Python35\python -m venv c:\path\to\myenv3 được chạy với tùy chọn def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)2, def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)3 nếu không. Trừ khi tùy chọn usage: venv [-h] [--system-site-packages] [--symlinks | --copies] [--clear] [--upgrade] [--without-pip] [--prompt PROMPT] [--upgrade-deps] ENV_DIR [ENV_DIR ...] Creates virtual Python environments in one or more target directories. positional arguments: ENV_DIR A directory to create the environment in. optional arguments: -h, --help show this help message and exit --system-site-packages Give the virtual environment access to the system site-packages dir. --symlinks Try to use symlinks rather than copies, when symlinks are not the default for the platform. --copies Try to use copies rather than symlinks, even when symlinks are the default for the platform. --clear Delete the contents of the environment directory if it already exists, before environment creation. --upgrade Upgrade the environment directory to use this version of Python, assuming Python has been upgraded in-place. --without-pip Skips installing or upgrading pip in the virtual environment (pip is bootstrapped by default) --prompt PROMPT Provides an alternative prompt prefix for this environment. --upgrade-deps Upgrade core dependencies: pip setuptools to the latest version in PyPI Once an environment has been created, you may wish to activate it, e.g. by sourcing an activate script in its bin directory.2 được đưa ra, def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)5 sẽ được gọi cho bootstrap def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)6 vào môi trường ảo. Nhiều đường dẫn có thể được đưa ra cho c:\>c:\Python35\python -m venv c:\path\to\myenv 3, trong trường hợp đó, một môi trường ảo giống hệt nhau sẽ được tạo ra, theo các tùy chọn đã cho, tại mỗi đường dẫn được cung cấp.Cách VENVS hoạt động trong đó Khi một thông dịch viên Python chạy từ môi trường ảo, def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)8 và def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)9 chỉ vào các thư mục của môi trường ảo, trong khi import os import os.path from subprocess import Popen, PIPE import sys from threading import Thread from urllib.parse import urlparse from urllib.request import urlretrieve import venv class ExtendedEnvBuilder(venv.EnvBuilder): """ This builder installs setuptools and pip so that you can pip or easy_install other packages into the created virtual environment. :param nodist: If true, setuptools and pip are not installed into the created virtual environment. :param nopip: If true, pip is not installed into the created virtual environment. :param progress: If setuptools or pip are installed, the progress of the installation can be monitored by passing a progress callable. If specified, it is called with two arguments: a string indicating some progress, and a context indicating where the string is coming from. The context argument can have one of three values: 'main', indicating that it is called from virtualize() itself, and 'stdout' and 'stderr', which are obtained by reading lines from the output streams of a subprocess which is used to install the app. If a callable is not specified, default progress information is output to sys.stderr. """ def __init__(self, *args, **kwargs): self.nodist = kwargs.pop('nodist', False) self.nopip = kwargs.pop('nopip', False) self.progress = kwargs.pop('progress', None) self.verbose = kwargs.pop('verbose', False) super().__init__(*args, **kwargs) def post_setup(self, context): """ Set up any packages which need to be pre-installed into the virtual environment being created. :param context: The information for the virtual environment creation request being processed. """ os.environ['VIRTUAL_ENV'] = context.env_dir if not self.nodist: self.install_setuptools(context) # Can't install pip without setuptools if not self.nopip and not self.nodist: self.install_pip(context) def reader(self, stream, context): """ Read lines from a subprocess' output stream and either pass to a progress callable (if specified) or write progress information to sys.stderr. """ progress = self.progress while True: s = stream.readline() if not s: break if progress is not None: progress(s, context) else: if not self.verbose: sys.stderr.write('.') else: sys.stderr.write(s.decode('utf-8')) sys.stderr.flush() stream.close() def install_script(self, context, name, url): _, _, path, _, _, _ = urlparse(url) fn = os.path.split(path)[-1] binpath = context.bin_path distpath = os.path.join(binpath, fn) # Download script into the virtual environment's binaries folder urlretrieve(url, distpath) progress = self.progress if self.verbose: term = '\n' else: term = '' if progress is not None: progress('Installing %s ...%s' % (name, term), 'main') else: sys.stderr.write('Installing %s ...%s' % (name, term)) sys.stderr.flush() # Install in the virtual environment args = [context.env_exe, fn] p = Popen(args, stdout=PIPE, stderr=PIPE, cwd=binpath) t1 = Thread(target=self.reader, args=(p.stdout, 'stdout')) t1.start() t2 = Thread(target=self.reader, args=(p.stderr, 'stderr')) t2.start() p.wait() t1.join() t2.join() if progress is not None: progress('done.', 'main') else: sys.stderr.write('done.\n') # Clean up - no longer needed os.unlink(distpath) def install_setuptools(self, context): """ Install setuptools in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bitbucket.org/pypa/setuptools/downloads/ez_setup.py' self.install_script(context, 'setuptools', url) # clear up the setuptools archive which gets downloaded pred = lambda o: o.startswith('setuptools-') and o.endswith('.tar.gz') files = filter(pred, os.listdir(context.bin_path)) for f in files: f = os.path.join(context.bin_path, f) os.unlink(f) def install_pip(self, context): """ Install pip in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bootstrap.pypa.io/get-pip.py' self.install_script(context, 'pip', url) def main(args=None): compatible = True if sys.version_info < (3, 3): compatible = False elif not hasattr(sys, 'base_prefix'): compatible = False if not compatible: raise ValueError('This script is only for use with ' 'Python 3.3 or later') else: import argparse parser = argparse.ArgumentParser(prog=__name__, description='Creates virtual Python ' 'environments in one or ' 'more target ' 'directories.') parser.add_argument('dirs', metavar='ENV_DIR', nargs='+', help='A directory in which to create the ' 'virtual environment.') parser.add_argument('--no-setuptools', default=False, action='store_true', dest='nodist', help="Don't install setuptools or pip in the " "virtual environment.") parser.add_argument('--no-pip', default=False, action='store_true', dest='nopip', help="Don't install pip in the virtual " "environment.") parser.add_argument('--system-site-packages', default=False, action='store_true', dest='system_site', help='Give the virtual environment access to the ' 'system site-packages dir.') if os.name == 'nt': use_symlinks = False else: use_symlinks = True parser.add_argument('--symlinks', default=use_symlinks, action='store_true', dest='symlinks', help='Try to use symlinks rather than copies, ' 'when symlinks are not the default for ' 'the platform.') parser.add_argument('--clear', default=False, action='store_true', dest='clear', help='Delete the contents of the ' 'virtual environment ' 'directory if it already ' 'exists, before virtual ' 'environment creation.') parser.add_argument('--upgrade', default=False, action='store_true', dest='upgrade', help='Upgrade the virtual ' 'environment directory to ' 'use this version of ' 'Python, assuming Python ' 'has been upgraded ' 'in-place.') parser.add_argument('--verbose', default=False, action='store_true', dest='verbose', help='Display the output ' 'from the scripts which ' 'install setuptools and pip.') options = parser.parse_args(args) if options.upgrade and options.clear: raise ValueError('you cannot supply --upgrade and --clear together.') builder = ExtendedEnvBuilder(system_site_packages=options.system_site, clear=options.clear, symlinks=options.symlinks, upgrade=options.upgrade, nodist=options.nodist, nopip=options.nopip, verbose=options.verbose) for d in options.dirs: builder.create(d) if __name__ == '__main__': rc = 1 try: main() rc = 0 except Exception as e: print('Error: %s' % e, file=sys.stderr) sys.exit(rc)0 và import os import os.path from subprocess import Popen, PIPE import sys from threading import Thread from urllib.parse import urlparse from urllib.request import urlretrieve import venv class ExtendedEnvBuilder(venv.EnvBuilder): """ This builder installs setuptools and pip so that you can pip or easy_install other packages into the created virtual environment. :param nodist: If true, setuptools and pip are not installed into the created virtual environment. :param nopip: If true, pip is not installed into the created virtual environment. :param progress: If setuptools or pip are installed, the progress of the installation can be monitored by passing a progress callable. If specified, it is called with two arguments: a string indicating some progress, and a context indicating where the string is coming from. The context argument can have one of three values: 'main', indicating that it is called from virtualize() itself, and 'stdout' and 'stderr', which are obtained by reading lines from the output streams of a subprocess which is used to install the app. If a callable is not specified, default progress information is output to sys.stderr. """ def __init__(self, *args, **kwargs): self.nodist = kwargs.pop('nodist', False) self.nopip = kwargs.pop('nopip', False) self.progress = kwargs.pop('progress', None) self.verbose = kwargs.pop('verbose', False) super().__init__(*args, **kwargs) def post_setup(self, context): """ Set up any packages which need to be pre-installed into the virtual environment being created. :param context: The information for the virtual environment creation request being processed. """ os.environ['VIRTUAL_ENV'] = context.env_dir if not self.nodist: self.install_setuptools(context) # Can't install pip without setuptools if not self.nopip and not self.nodist: self.install_pip(context) def reader(self, stream, context): """ Read lines from a subprocess' output stream and either pass to a progress callable (if specified) or write progress information to sys.stderr. """ progress = self.progress while True: s = stream.readline() if not s: break if progress is not None: progress(s, context) else: if not self.verbose: sys.stderr.write('.') else: sys.stderr.write(s.decode('utf-8')) sys.stderr.flush() stream.close() def install_script(self, context, name, url): _, _, path, _, _, _ = urlparse(url) fn = os.path.split(path)[-1] binpath = context.bin_path distpath = os.path.join(binpath, fn) # Download script into the virtual environment's binaries folder urlretrieve(url, distpath) progress = self.progress if self.verbose: term = '\n' else: term = '' if progress is not None: progress('Installing %s ...%s' % (name, term), 'main') else: sys.stderr.write('Installing %s ...%s' % (name, term)) sys.stderr.flush() # Install in the virtual environment args = [context.env_exe, fn] p = Popen(args, stdout=PIPE, stderr=PIPE, cwd=binpath) t1 = Thread(target=self.reader, args=(p.stdout, 'stdout')) t1.start() t2 = Thread(target=self.reader, args=(p.stderr, 'stderr')) t2.start() p.wait() t1.join() t2.join() if progress is not None: progress('done.', 'main') else: sys.stderr.write('done.\n') # Clean up - no longer needed os.unlink(distpath) def install_setuptools(self, context): """ Install setuptools in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bitbucket.org/pypa/setuptools/downloads/ez_setup.py' self.install_script(context, 'setuptools', url) # clear up the setuptools archive which gets downloaded pred = lambda o: o.startswith('setuptools-') and o.endswith('.tar.gz') files = filter(pred, os.listdir(context.bin_path)) for f in files: f = os.path.join(context.bin_path, f) os.unlink(f) def install_pip(self, context): """ Install pip in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bootstrap.pypa.io/get-pip.py' self.install_script(context, 'pip', url) def main(args=None): compatible = True if sys.version_info < (3, 3): compatible = False elif not hasattr(sys, 'base_prefix'): compatible = False if not compatible: raise ValueError('This script is only for use with ' 'Python 3.3 or later') else: import argparse parser = argparse.ArgumentParser(prog=__name__, description='Creates virtual Python ' 'environments in one or ' 'more target ' 'directories.') parser.add_argument('dirs', metavar='ENV_DIR', nargs='+', help='A directory in which to create the ' 'virtual environment.') parser.add_argument('--no-setuptools', default=False, action='store_true', dest='nodist', help="Don't install setuptools or pip in the " "virtual environment.") parser.add_argument('--no-pip', default=False, action='store_true', dest='nopip', help="Don't install pip in the virtual " "environment.") parser.add_argument('--system-site-packages', default=False, action='store_true', dest='system_site', help='Give the virtual environment access to the ' 'system site-packages dir.') if os.name == 'nt': use_symlinks = False else: use_symlinks = True parser.add_argument('--symlinks', default=use_symlinks, action='store_true', dest='symlinks', help='Try to use symlinks rather than copies, ' 'when symlinks are not the default for ' 'the platform.') parser.add_argument('--clear', default=False, action='store_true', dest='clear', help='Delete the contents of the ' 'virtual environment ' 'directory if it already ' 'exists, before virtual ' 'environment creation.') parser.add_argument('--upgrade', default=False, action='store_true', dest='upgrade', help='Upgrade the virtual ' 'environment directory to ' 'use this version of ' 'Python, assuming Python ' 'has been upgraded ' 'in-place.') parser.add_argument('--verbose', default=False, action='store_true', dest='verbose', help='Display the output ' 'from the scripts which ' 'install setuptools and pip.') options = parser.parse_args(args) if options.upgrade and options.clear: raise ValueError('you cannot supply --upgrade and --clear together.') builder = ExtendedEnvBuilder(system_site_packages=options.system_site, clear=options.clear, symlinks=options.symlinks, upgrade=options.upgrade, nodist=options.nodist, nopip=options.nopip, verbose=options.verbose) for d in options.dirs: builder.create(d) if __name__ == '__main__': rc = 1 try: main() rc = 0 except Exception as e: print('Error: %s' % e, file=sys.stderr) sys.exit(rc)1 chỉ vào các thư mục của Python cơ sở được sử dụng để tạo ra môi trường. Nó là đủ để kiểm tra import os import os.path from subprocess import Popen, PIPE import sys from threading import Thread from urllib.parse import urlparse from urllib.request import urlretrieve import venv class ExtendedEnvBuilder(venv.EnvBuilder): """ This builder installs setuptools and pip so that you can pip or easy_install other packages into the created virtual environment. :param nodist: If true, setuptools and pip are not installed into the created virtual environment. :param nopip: If true, pip is not installed into the created virtual environment. :param progress: If setuptools or pip are installed, the progress of the installation can be monitored by passing a progress callable. If specified, it is called with two arguments: a string indicating some progress, and a context indicating where the string is coming from. The context argument can have one of three values: 'main', indicating that it is called from virtualize() itself, and 'stdout' and 'stderr', which are obtained by reading lines from the output streams of a subprocess which is used to install the app. If a callable is not specified, default progress information is output to sys.stderr. """ def __init__(self, *args, **kwargs): self.nodist = kwargs.pop('nodist', False) self.nopip = kwargs.pop('nopip', False) self.progress = kwargs.pop('progress', None) self.verbose = kwargs.pop('verbose', False) super().__init__(*args, **kwargs) def post_setup(self, context): """ Set up any packages which need to be pre-installed into the virtual environment being created. :param context: The information for the virtual environment creation request being processed. """ os.environ['VIRTUAL_ENV'] = context.env_dir if not self.nodist: self.install_setuptools(context) # Can't install pip without setuptools if not self.nopip and not self.nodist: self.install_pip(context) def reader(self, stream, context): """ Read lines from a subprocess' output stream and either pass to a progress callable (if specified) or write progress information to sys.stderr. """ progress = self.progress while True: s = stream.readline() if not s: break if progress is not None: progress(s, context) else: if not self.verbose: sys.stderr.write('.') else: sys.stderr.write(s.decode('utf-8')) sys.stderr.flush() stream.close() def install_script(self, context, name, url): _, _, path, _, _, _ = urlparse(url) fn = os.path.split(path)[-1] binpath = context.bin_path distpath = os.path.join(binpath, fn) # Download script into the virtual environment's binaries folder urlretrieve(url, distpath) progress = self.progress if self.verbose: term = '\n' else: term = '' if progress is not None: progress('Installing %s ...%s' % (name, term), 'main') else: sys.stderr.write('Installing %s ...%s' % (name, term)) sys.stderr.flush() # Install in the virtual environment args = [context.env_exe, fn] p = Popen(args, stdout=PIPE, stderr=PIPE, cwd=binpath) t1 = Thread(target=self.reader, args=(p.stdout, 'stdout')) t1.start() t2 = Thread(target=self.reader, args=(p.stderr, 'stderr')) t2.start() p.wait() t1.join() t2.join() if progress is not None: progress('done.', 'main') else: sys.stderr.write('done.\n') # Clean up - no longer needed os.unlink(distpath) def install_setuptools(self, context): """ Install setuptools in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bitbucket.org/pypa/setuptools/downloads/ez_setup.py' self.install_script(context, 'setuptools', url) # clear up the setuptools archive which gets downloaded pred = lambda o: o.startswith('setuptools-') and o.endswith('.tar.gz') files = filter(pred, os.listdir(context.bin_path)) for f in files: f = os.path.join(context.bin_path, f) os.unlink(f) def install_pip(self, context): """ Install pip in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bootstrap.pypa.io/get-pip.py' self.install_script(context, 'pip', url) def main(args=None): compatible = True if sys.version_info < (3, 3): compatible = False elif not hasattr(sys, 'base_prefix'): compatible = False if not compatible: raise ValueError('This script is only for use with ' 'Python 3.3 or later') else: import argparse parser = argparse.ArgumentParser(prog=__name__, description='Creates virtual Python ' 'environments in one or ' 'more target ' 'directories.') parser.add_argument('dirs', metavar='ENV_DIR', nargs='+', help='A directory in which to create the ' 'virtual environment.') parser.add_argument('--no-setuptools', default=False, action='store_true', dest='nodist', help="Don't install setuptools or pip in the " "virtual environment.") parser.add_argument('--no-pip', default=False, action='store_true', dest='nopip', help="Don't install pip in the virtual " "environment.") parser.add_argument('--system-site-packages', default=False, action='store_true', dest='system_site', help='Give the virtual environment access to the ' 'system site-packages dir.') if os.name == 'nt': use_symlinks = False else: use_symlinks = True parser.add_argument('--symlinks', default=use_symlinks, action='store_true', dest='symlinks', help='Try to use symlinks rather than copies, ' 'when symlinks are not the default for ' 'the platform.') parser.add_argument('--clear', default=False, action='store_true', dest='clear', help='Delete the contents of the ' 'virtual environment ' 'directory if it already ' 'exists, before virtual ' 'environment creation.') parser.add_argument('--upgrade', default=False, action='store_true', dest='upgrade', help='Upgrade the virtual ' 'environment directory to ' 'use this version of ' 'Python, assuming Python ' 'has been upgraded ' 'in-place.') parser.add_argument('--verbose', default=False, action='store_true', dest='verbose', help='Display the output ' 'from the scripts which ' 'install setuptools and pip.') options = parser.parse_args(args) if options.upgrade and options.clear: raise ValueError('you cannot supply --upgrade and --clear together.') builder = ExtendedEnvBuilder(system_site_packages=options.system_site, clear=options.clear, symlinks=options.symlinks, upgrade=options.upgrade, nodist=options.nodist, nopip=options.nopip, verbose=options.verbose) for d in options.dirs: builder.create(d) if __name__ == '__main__': rc = 1 try: main() rc = 0 except Exception as e: print('Error: %s' % e, file=sys.stderr) sys.exit(rc)2 để xác định xem trình thông dịch hiện tại có chạy từ môi trường ảo hay không.!python will invoke the environment’s Python interpreter and you can run installed scripts without having to use their full path. The invocation of the activation script is platform-specific ( import os import os.path from subprocess import Popen, PIPE import sys from threading import Thread from urllib.parse import urlparse from urllib.request import urlretrieve import venv class ExtendedEnvBuilder(venv.EnvBuilder): """ This builder installs setuptools and pip so that you can pip or easy_install other packages into the created virtual environment. :param nodist: If true, setuptools and pip are not installed into the created virtual environment. :param nopip: If true, pip is not installed into the created virtual environment. :param progress: If setuptools or pip are installed, the progress of the installation can be monitored by passing a progress callable. If specified, it is called with two arguments: a string indicating some progress, and a context indicating where the string is coming from. The context argument can have one of three values: 'main', indicating that it is called from virtualize() itself, and 'stdout' and 'stderr', which are obtained by reading lines from the output streams of a subprocess which is used to install the app. If a callable is not specified, default progress information is output to sys.stderr. """ def __init__(self, *args, **kwargs): self.nodist = kwargs.pop('nodist', False) self.nopip = kwargs.pop('nopip', False) self.progress = kwargs.pop('progress', None) self.verbose = kwargs.pop('verbose', False) super().__init__(*args, **kwargs) def post_setup(self, context): """ Set up any packages which need to be pre-installed into the virtual environment being created. :param context: The information for the virtual environment creation request being processed. """ os.environ['VIRTUAL_ENV'] = context.env_dir if not self.nodist: self.install_setuptools(context) # Can't install pip without setuptools if not self.nopip and not self.nodist: self.install_pip(context) def reader(self, stream, context): """ Read lines from a subprocess' output stream and either pass to a progress callable (if specified) or write progress information to sys.stderr. """ progress = self.progress while True: s = stream.readline() if not s: break if progress is not None: progress(s, context) else: if not self.verbose: sys.stderr.write('.') else: sys.stderr.write(s.decode('utf-8')) sys.stderr.flush() stream.close() def install_script(self, context, name, url): _, _, path, _, _, _ = urlparse(url) fn = os.path.split(path)[-1] binpath = context.bin_path distpath = os.path.join(binpath, fn) # Download script into the virtual environment's binaries folder urlretrieve(url, distpath) progress = self.progress if self.verbose: term = '\n' else: term = '' if progress is not None: progress('Installing %s ...%s' % (name, term), 'main') else: sys.stderr.write('Installing %s ...%s' % (name, term)) sys.stderr.flush() # Install in the virtual environment args = [context.env_exe, fn] p = Popen(args, stdout=PIPE, stderr=PIPE, cwd=binpath) t1 = Thread(target=self.reader, args=(p.stdout, 'stdout')) t1.start() t2 = Thread(target=self.reader, args=(p.stderr, 'stderr')) t2.start() p.wait() t1.join() t2.join() if progress is not None: progress('done.', 'main') else: sys.stderr.write('done.\n') # Clean up - no longer needed os.unlink(distpath) def install_setuptools(self, context): """ Install setuptools in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bitbucket.org/pypa/setuptools/downloads/ez_setup.py' self.install_script(context, 'setuptools', url) # clear up the setuptools archive which gets downloaded pred = lambda o: o.startswith('setuptools-') and o.endswith('.tar.gz') files = filter(pred, os.listdir(context.bin_path)) for f in files: f = os.path.join(context.bin_path, f) os.unlink(f) def install_pip(self, context): """ Install pip in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bootstrap.pypa.io/get-pip.py' self.install_script(context, 'pip', url) def main(args=None): compatible = True if sys.version_info < (3, 3): compatible = False elif not hasattr(sys, 'base_prefix'): compatible = False if not compatible: raise ValueError('This script is only for use with ' 'Python 3.3 or later') else: import argparse parser = argparse.ArgumentParser(prog=__name__, description='Creates virtual Python ' 'environments in one or ' 'more target ' 'directories.') parser.add_argument('dirs', metavar='ENV_DIR', nargs='+', help='A directory in which to create the ' 'virtual environment.') parser.add_argument('--no-setuptools', default=False, action='store_true', dest='nodist', help="Don't install setuptools or pip in the " "virtual environment.") parser.add_argument('--no-pip', default=False, action='store_true', dest='nopip', help="Don't install pip in the virtual " "environment.") parser.add_argument('--system-site-packages', default=False, action='store_true', dest='system_site', help='Give the virtual environment access to the ' 'system site-packages dir.') if os.name == 'nt': use_symlinks = False else: use_symlinks = True parser.add_argument('--symlinks', default=use_symlinks, action='store_true', dest='symlinks', help='Try to use symlinks rather than copies, ' 'when symlinks are not the default for ' 'the platform.') parser.add_argument('--clear', default=False, action='store_true', dest='clear', help='Delete the contents of the ' 'virtual environment ' 'directory if it already ' 'exists, before virtual ' 'environment creation.') parser.add_argument('--upgrade', default=False, action='store_true', dest='upgrade', help='Upgrade the virtual ' 'environment directory to ' 'use this version of ' 'Python, assuming Python ' 'has been upgraded ' 'in-place.') parser.add_argument('--verbose', default=False, action='store_true', dest='verbose', help='Display the output ' 'from the scripts which ' 'install setuptools and pip.') options = parser.parse_args(args) if options.upgrade and options.clear: raise ValueError('you cannot supply --upgrade and --clear together.') builder = ExtendedEnvBuilder(system_site_packages=options.system_site, clear=options.clear, symlinks=options.symlinks, upgrade=options.upgrade, nodist=options.nodist, nopip=options.nopip, verbose=options.verbose) for d in options.dirs: builder.create(d) if __name__ == '__main__': rc = 1 try: main() rc = 0 except Exception as e: print('Error: %s' % e, file=sys.stderr) sys.exit(rc)6 must be replaced by the path to the directory containing the virtual environment):
Powershell!fish and !csh activation scripts. các cửa sổPowerShell activation scripts installed under POSIX for PowerShell Core support. Mới trong Phiên bản 3.4:! Cá và! Các kịch bản kích hoạt CSH. Mới trong phiên bản 3.8: Các tập lệnh kích hoạt PowerShell được cài đặt theo POSIX cho hỗ trợ Core PowerShell.Python Launcher for Windows installed. Thus, double-clicking an installed script in a Windows Explorer window should run it with the correct interpreter without the environment needing to be activated or on the c:\>python -m venv c:\path\to\myenv8. Bạn không cần phải kích hoạt một môi trường ảo, vì bạn chỉ có thể chỉ định đường dẫn đầy đủ đến môi trường đó là phiên dịch viên Python Python khi gọi Python. Hơn nữa, tất cả các tập lệnh được cài đặt trong môi trường nên được chạy mà không cần kích hoạt nó. Để đạt được điều này, các tập lệnh được cài đặt vào các môi trường ảo, có một dòng Shebang Shebang, chỉ vào môi trường phiên dịch Python Python, tức là c:\>python -m venv c:\path\to\myenv8. Trên Windows, xử lý dòng Shebang Shebang được hỗ trợ nếu bạn đã cài đặt trình khởi chạy Python cho Windows. Do đó, nhấp đúp vào một tập lệnh được cài đặt trong cửa sổ Windows Explorer sẽ chạy nó với trình thông dịch chính xác mà không cần môi trường cần được kích hoạt hoặc trên c:\>python -m venv c:\path\to\myenv8. Khi một môi trường ảo đã được kích hoạt, biến môi trường Bạn có thể hủy kích hoạt một môi trường ảo bằng cách gõ c:\>c:\Python35\python -m venv c:\path\to\myenv0 vào vỏ của bạn. Cơ chế chính xác là đặc trưng cho nền tảng và là một chi tiết triển khai nội bộ (thông thường, chức năng tập lệnh hoặc shell sẽ được sử dụng). Api¶Phương pháp cấp cao được mô tả ở trên sử dụng API đơn giản cung cấp các cơ chế cho người tạo môi trường ảo của bên thứ ba để tùy chỉnh tạo môi trường theo nhu cầu của họ, lớp ____72. classvenv.envbuilder (System_site_packages = falsevenv.EnvBuilder(system_site_packages=False, clear=False, symlinks=False, upgrade=False, with_pip=False, prompt=None, upgrade_deps=False)¶Lớp
Đã thay đổi trong phiên bản 3.4: Đã thêm tham số Mới trong phiên bản 3.6: Đã thêm tham số Mới trong phiên bản 3.9: Đã thêm tham số Người tạo ra các công cụ môi trường ảo của bên thứ ba sẽ được tự do sử dụng lớp Env-Builder được trả lại là một đối tượng có phương thức, Tạo một môi trường ảo bằng cách chỉ định thư mục đích (tuyệt đối hoặc liên quan đến thư mục hiện tại) là chứa môi trường ảo. Phương pháp Phương pháp def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context) Mỗi phương thức Tạo thư mục môi trường và tất cả các thư mục con cần thiết đã không tồn tại và trả về một đối tượng ngữ cảnh. Đối tượng bối cảnh này chỉ là một người giữ cho các thuộc tính (như đường dẫn) để sử dụng bởi các phương thức khác. Nếu c:\>c:\Python35\python -m venv c:\path\to\myenv01, nội dung của thư mục môi trường sẽ được xóa và sau đó tất cả các thư mục con cần thiết sẽ được tái tạo. Đối tượng bối cảnh được trả về là c:\>c:\Python35\python -m venv c:\path\to\myenv02 với các thuộc tính sau:
Thay đổi trong phiên bản 3.12: Thuộc tính c:\>c:\Python35\python -m venv c:\path\to\myenv14 was added to the context, and the context object was documented. Thay đổi trong phiên bản 3.11: Sơ đồ cài đặt SYSConfig VETV được sử dụng để xây dựng các đường dẫn của các thư mục được tạo.The venv sysconfig installation scheme is used to construct the paths of the created directories. created_configuration (bối cảnh) ¶(context)¶Tạo tệp cấu hình c:\>c:\Python35\python -m venv c:\path\to\myenv8 trong môi trường. setup_python (bối cảnh) ¶(context)¶ Tạo một bản sao hoặc Symlink cho Python thực thi trong môi trường. Trên các hệ thống POSIX, nếu một c:\>c:\Python35\python -m venv c:\path\to\myenv25 thực thi cụ thể được sử dụng, các liên kết symlink thành c:\>c:\Python35\python -m venv c:\path\to\myenv26 và c:\>c:\Python35\python -m venv c:\path\to\myenv27 sẽ được tạo chỉ vào việc thực thi đó, trừ khi các tệp có tên đó đã tồn tại. setup_scripts (bối cảnh) ¶(context)¶ Cài đặt các tập lệnh kích hoạt phù hợp với nền tảng vào môi trường ảo. nâng cấp_dependencies (bối cảnh) ¶(context)¶Nâng cấp các gói phụ thuộc VEN Core (hiện tại def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)6 và c:\>c:\Python35\python -m venv c:\path\to\myenv29) trong môi trường. Điều này được thực hiện bằng cách bắn ra def create(self, env_dir): """ Create a virtualized Python environment in a directory. env_dir is the target directory to create an environment in. """ env_dir = os.path.abspath(env_dir) context = self.ensure_directories(env_dir) self.create_configuration(context) self.setup_python(context) self.setup_scripts(context) self.post_setup(context)6 thực thi trong môi trường. Mới trong phiên bản 3.9. post_setup (bối cảnh) ¶(context)¶Một phương thức giữ chỗ có thể được ghi đè trong các triển khai của bên thứ ba để cài đặt sẵn các gói trong môi trường ảo hoặc thực hiện các bước sau sáng tạo khác. Đã thay đổi trong phiên bản 3.7.2: Windows hiện sử dụng các tập lệnh chuyển hướng cho c:\>c:\Python35\python -m venv c:\path\to\myenv31 instead of copying the actual binaries. In 3.7.2 only python_env/bin/activate 7 does nothing unless running from a build in the source tree.Đã thay đổi trong phiên bản 3.7.3: Windows sao chép các tập lệnh chuyển hướng như một phần của Ngoài ra, Đường dẫn là đường dẫn đến một thư mục nên chứa các thư mục con phổ biến, thì Poss, thì, NT NT, mỗi tập lệnh có các tập lệnh dành cho thư mục bin trong môi trường. Nội dung của Common Common và thư mục tương ứng với c:\>c:\Python35\python -m venv c:\path\to\myenv38 được sao chép sau khi một số văn bản thay thế người giữ chỗ:
Các thư mục được phép tồn tại (vì khi một môi trường hiện tại đang được nâng cấp). Ngoài ra còn có chức năng tiện lợi cấp độ mô-đun: venv.create (env_dir, system_site_packages = false, rõ ràng = false, symlinks = false, with_pip = falsecreate(env_dir, system_site_packages=False, clear=False, symlinks=False, with_pip=False, prompt=None, upgrade_deps=False)¶Tạo một c:\>c:\Python35\python -m venv c:\path\to\myenv47 của nó với đối số env_dir. Mới trong phiên bản 3.3. Đã thay đổi trong phiên bản 3.4: Đã thêm tham số Đã thay đổi trong phiên bản 3.6: Đã thêm tham số Đã thay đổi trong phiên bản 3.9: Đã thêm tham số Một ví dụ về việc mở rộng ____ 72¶Tập lệnh sau đây cho thấy cách mở rộng import os import os.path from subprocess import Popen, PIPE import sys from threading import Thread from urllib.parse import urlparse from urllib.request import urlretrieve import venv class ExtendedEnvBuilder(venv.EnvBuilder): """ This builder installs setuptools and pip so that you can pip or easy_install other packages into the created virtual environment. :param nodist: If true, setuptools and pip are not installed into the created virtual environment. :param nopip: If true, pip is not installed into the created virtual environment. :param progress: If setuptools or pip are installed, the progress of the installation can be monitored by passing a progress callable. If specified, it is called with two arguments: a string indicating some progress, and a context indicating where the string is coming from. The context argument can have one of three values: 'main', indicating that it is called from virtualize() itself, and 'stdout' and 'stderr', which are obtained by reading lines from the output streams of a subprocess which is used to install the app. If a callable is not specified, default progress information is output to sys.stderr. """ def __init__(self, *args, **kwargs): self.nodist = kwargs.pop('nodist', False) self.nopip = kwargs.pop('nopip', False) self.progress = kwargs.pop('progress', None) self.verbose = kwargs.pop('verbose', False) super().__init__(*args, **kwargs) def post_setup(self, context): """ Set up any packages which need to be pre-installed into the virtual environment being created. :param context: The information for the virtual environment creation request being processed. """ os.environ['VIRTUAL_ENV'] = context.env_dir if not self.nodist: self.install_setuptools(context) # Can't install pip without setuptools if not self.nopip and not self.nodist: self.install_pip(context) def reader(self, stream, context): """ Read lines from a subprocess' output stream and either pass to a progress callable (if specified) or write progress information to sys.stderr. """ progress = self.progress while True: s = stream.readline() if not s: break if progress is not None: progress(s, context) else: if not self.verbose: sys.stderr.write('.') else: sys.stderr.write(s.decode('utf-8')) sys.stderr.flush() stream.close() def install_script(self, context, name, url): _, _, path, _, _, _ = urlparse(url) fn = os.path.split(path)[-1] binpath = context.bin_path distpath = os.path.join(binpath, fn) # Download script into the virtual environment's binaries folder urlretrieve(url, distpath) progress = self.progress if self.verbose: term = '\n' else: term = '' if progress is not None: progress('Installing %s ...%s' % (name, term), 'main') else: sys.stderr.write('Installing %s ...%s' % (name, term)) sys.stderr.flush() # Install in the virtual environment args = [context.env_exe, fn] p = Popen(args, stdout=PIPE, stderr=PIPE, cwd=binpath) t1 = Thread(target=self.reader, args=(p.stdout, 'stdout')) t1.start() t2 = Thread(target=self.reader, args=(p.stderr, 'stderr')) t2.start() p.wait() t1.join() t2.join() if progress is not None: progress('done.', 'main') else: sys.stderr.write('done.\n') # Clean up - no longer needed os.unlink(distpath) def install_setuptools(self, context): """ Install setuptools in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bitbucket.org/pypa/setuptools/downloads/ez_setup.py' self.install_script(context, 'setuptools', url) # clear up the setuptools archive which gets downloaded pred = lambda o: o.startswith('setuptools-') and o.endswith('.tar.gz') files = filter(pred, os.listdir(context.bin_path)) for f in files: f = os.path.join(context.bin_path, f) os.unlink(f) def install_pip(self, context): """ Install pip in the virtual environment. :param context: The information for the virtual environment creation request being processed. """ url = 'https://bootstrap.pypa.io/get-pip.py' self.install_script(context, 'pip', url) def main(args=None): compatible = True if sys.version_info < (3, 3): compatible = False elif not hasattr(sys, 'base_prefix'): compatible = False if not compatible: raise ValueError('This script is only for use with ' 'Python 3.3 or later') else: import argparse parser = argparse.ArgumentParser(prog=__name__, description='Creates virtual Python ' 'environments in one or ' 'more target ' 'directories.') parser.add_argument('dirs', metavar='ENV_DIR', nargs='+', help='A directory in which to create the ' 'virtual environment.') parser.add_argument('--no-setuptools', default=False, action='store_true', dest='nodist', help="Don't install setuptools or pip in the " "virtual environment.") parser.add_argument('--no-pip', default=False, action='store_true', dest='nopip', help="Don't install pip in the virtual " "environment.") parser.add_argument('--system-site-packages', default=False, action='store_true', dest='system_site', help='Give the virtual environment access to the ' 'system site-packages dir.') if os.name == 'nt': use_symlinks = False else: use_symlinks = True parser.add_argument('--symlinks', default=use_symlinks, action='store_true', dest='symlinks', help='Try to use symlinks rather than copies, ' 'when symlinks are not the default for ' 'the platform.') parser.add_argument('--clear', default=False, action='store_true', dest='clear', help='Delete the contents of the ' 'virtual environment ' 'directory if it already ' 'exists, before virtual ' 'environment creation.') parser.add_argument('--upgrade', default=False, action='store_true', dest='upgrade', help='Upgrade the virtual ' 'environment directory to ' 'use this version of ' 'Python, assuming Python ' 'has been upgraded ' 'in-place.') parser.add_argument('--verbose', default=False, action='store_true', dest='verbose', help='Display the output ' 'from the scripts which ' 'install setuptools and pip.') options = parser.parse_args(args) if options.upgrade and options.clear: raise ValueError('you cannot supply --upgrade and --clear together.') builder = ExtendedEnvBuilder(system_site_packages=options.system_site, clear=options.clear, symlinks=options.symlinks, upgrade=options.upgrade, nodist=options.nodist, nopip=options.nopip, verbose=options.verbose) for d in options.dirs: builder.create(d) if __name__ == '__main__': rc = 1 try: main() rc = 0 except Exception as e: print('Error: %s' % e, file=sys.stderr) sys.exit(rc) Kịch bản này cũng có sẵn để tải xuống trực tuyến. |