Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 1 | """ |
| 2 | Virtual environment (venv) package for Python. Based on PEP 405. |
| 3 | |
Vinay Sajip | 2895244 | 2012-06-25 00:47:46 +0100 | [diff] [blame] | 4 | Copyright (C) 2011-2012 Vinay Sajip. |
| 5 | Licensed to the PSF under a contributor agreement. |
Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 6 | |
Vinay Sajip | 4469746 | 2012-05-28 16:33:01 +0100 | [diff] [blame] | 7 | usage: python -m venv [-h] [--system-site-packages] [--symlinks] [--clear] |
| 8 | [--upgrade] |
Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 9 | ENV_DIR [ENV_DIR ...] |
| 10 | |
| 11 | Creates virtual Python environments in one or more target directories. |
| 12 | |
| 13 | positional arguments: |
| 14 | ENV_DIR A directory to create the environment in. |
| 15 | |
| 16 | optional arguments: |
| 17 | -h, --help show this help message and exit |
Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 18 | --system-site-packages |
| 19 | Give the virtual environment access to the system |
| 20 | site-packages dir. |
| 21 | --symlinks Attempt to symlink rather than copy. |
| 22 | --clear Delete the environment directory if it already exists. |
| 23 | If not specified and the directory exists, an error is |
| 24 | raised. |
| 25 | --upgrade Upgrade the environment directory to use this version |
| 26 | of Python, assuming Python has been upgraded in-place. |
Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 27 | """ |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 28 | import base64 |
| 29 | import io |
| 30 | import logging |
| 31 | import os |
| 32 | import os.path |
| 33 | import shutil |
| 34 | import sys |
Vinay Sajip | 4469746 | 2012-05-28 16:33:01 +0100 | [diff] [blame] | 35 | import sysconfig |
Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 36 | try: |
| 37 | import threading |
| 38 | except ImportError: |
| 39 | threading = None |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 40 | |
| 41 | logger = logging.getLogger(__name__) |
| 42 | |
| 43 | class Context: |
| 44 | """ |
Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 45 | Holds information about a current venv creation/upgrade request. |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 46 | """ |
| 47 | pass |
| 48 | |
| 49 | |
| 50 | class EnvBuilder: |
| 51 | """ |
| 52 | This class exists to allow virtual environment creation to be |
| 53 | customised. The constructor parameters determine the builder's |
| 54 | behaviour when called upon to create a virtual environment. |
| 55 | |
| 56 | By default, the builder makes the system (global) site-packages dir |
Vinay Sajip | 87ed599 | 2012-11-14 11:18:35 +0000 | [diff] [blame] | 57 | *un*available to the created environment. |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 58 | |
Vinay Sajip | 87ed599 | 2012-11-14 11:18:35 +0000 | [diff] [blame] | 59 | If invoked using the Python -m option, the default is to use copying |
| 60 | on Windows platforms but symlinks elsewhere. If instantiated some |
| 61 | other way, the default is to *not* use symlinks. |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 62 | |
| 63 | :param system_site_packages: If True, the system (global) site-packages |
| 64 | dir is available to created environments. |
| 65 | :param clear: If True and the target directory exists, it is deleted. |
| 66 | Otherwise, if the target directory exists, an error is |
| 67 | raised. |
| 68 | :param symlinks: If True, attempt to symlink rather than copy files into |
| 69 | virtual environment. |
| 70 | :param upgrade: If True, upgrade an existing virtual environment. |
| 71 | """ |
| 72 | |
| 73 | def __init__(self, system_site_packages=False, clear=False, |
| 74 | symlinks=False, upgrade=False): |
| 75 | self.system_site_packages = system_site_packages |
| 76 | self.clear = clear |
| 77 | self.symlinks = symlinks |
| 78 | self.upgrade = upgrade |
| 79 | |
| 80 | def create(self, env_dir): |
| 81 | """ |
| 82 | Create a virtual environment in a directory. |
| 83 | |
| 84 | :param env_dir: The target directory to create an environment in. |
| 85 | |
| 86 | """ |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 87 | env_dir = os.path.abspath(env_dir) |
| 88 | context = self.ensure_directories(env_dir) |
| 89 | self.create_configuration(context) |
| 90 | self.setup_python(context) |
| 91 | if not self.upgrade: |
| 92 | self.setup_scripts(context) |
| 93 | self.post_setup(context) |
| 94 | |
Vinay Sajip | bd40d3e | 2012-10-11 17:22:45 +0100 | [diff] [blame] | 95 | def clear_directory(self, path): |
| 96 | for fn in os.listdir(path): |
| 97 | fn = os.path.join(path, fn) |
| 98 | if os.path.islink(fn) or os.path.isfile(fn): |
| 99 | os.remove(fn) |
| 100 | elif os.path.isdir(fn): |
| 101 | shutil.rmtree(fn) |
| 102 | |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 103 | def ensure_directories(self, env_dir): |
| 104 | """ |
| 105 | Create the directories for the environment. |
| 106 | |
| 107 | Returns a context object which holds paths in the environment, |
| 108 | for use by subsequent logic. |
| 109 | """ |
| 110 | |
| 111 | def create_if_needed(d): |
| 112 | if not os.path.exists(d): |
| 113 | os.makedirs(d) |
Vinay Sajip | bd40d3e | 2012-10-11 17:22:45 +0100 | [diff] [blame] | 114 | elif os.path.islink(d) or os.path.isfile(d): |
| 115 | raise ValueError('Unable to create directory %r' % d) |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 116 | |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 117 | if os.path.exists(env_dir) and self.clear: |
Vinay Sajip | bd40d3e | 2012-10-11 17:22:45 +0100 | [diff] [blame] | 118 | self.clear_directory(env_dir) |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 119 | context = Context() |
| 120 | context.env_dir = env_dir |
| 121 | context.env_name = os.path.split(env_dir)[1] |
| 122 | context.prompt = '(%s) ' % context.env_name |
| 123 | create_if_needed(env_dir) |
| 124 | env = os.environ |
Vinay Sajip | 2895244 | 2012-06-25 00:47:46 +0100 | [diff] [blame] | 125 | if sys.platform == 'darwin' and '__PYVENV_LAUNCHER__' in env: |
| 126 | executable = os.environ['__PYVENV_LAUNCHER__'] |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 127 | else: |
| 128 | executable = sys.executable |
| 129 | dirname, exename = os.path.split(os.path.abspath(executable)) |
| 130 | context.executable = executable |
| 131 | context.python_dir = dirname |
| 132 | context.python_exe = exename |
| 133 | if sys.platform == 'win32': |
| 134 | binname = 'Scripts' |
| 135 | incpath = 'Include' |
| 136 | libpath = os.path.join(env_dir, 'Lib', 'site-packages') |
| 137 | else: |
| 138 | binname = 'bin' |
| 139 | incpath = 'include' |
| 140 | libpath = os.path.join(env_dir, 'lib', 'python%d.%d' % sys.version_info[:2], 'site-packages') |
| 141 | context.inc_path = path = os.path.join(env_dir, incpath) |
| 142 | create_if_needed(path) |
| 143 | create_if_needed(libpath) |
| 144 | context.bin_path = binpath = os.path.join(env_dir, binname) |
| 145 | context.bin_name = binname |
| 146 | context.env_exe = os.path.join(binpath, exename) |
| 147 | create_if_needed(binpath) |
| 148 | return context |
| 149 | |
| 150 | def create_configuration(self, context): |
| 151 | """ |
| 152 | Create a configuration file indicating where the environment's Python |
| 153 | was copied from, and whether the system site-packages should be made |
| 154 | available in the environment. |
| 155 | |
| 156 | :param context: The information for the environment creation request |
| 157 | being processed. |
| 158 | """ |
| 159 | context.cfg_path = path = os.path.join(context.env_dir, 'pyvenv.cfg') |
| 160 | with open(path, 'w', encoding='utf-8') as f: |
| 161 | f.write('home = %s\n' % context.python_dir) |
| 162 | if self.system_site_packages: |
| 163 | incl = 'true' |
| 164 | else: |
| 165 | incl = 'false' |
| 166 | f.write('include-system-site-packages = %s\n' % incl) |
| 167 | f.write('version = %d.%d.%d\n' % sys.version_info[:3]) |
| 168 | |
| 169 | if os.name == 'nt': |
| 170 | def include_binary(self, f): |
| 171 | if f.endswith(('.pyd', '.dll')): |
| 172 | result = True |
| 173 | else: |
| 174 | result = f.startswith('python') and f.endswith('.exe') |
| 175 | return result |
| 176 | |
| 177 | def symlink_or_copy(self, src, dst): |
| 178 | """ |
| 179 | Try symlinking a file, and if that fails, fall back to copying. |
| 180 | """ |
| 181 | force_copy = not self.symlinks |
| 182 | if not force_copy: |
| 183 | try: |
| 184 | if not os.path.islink(dst): # can't link to itself! |
| 185 | os.symlink(src, dst) |
| 186 | except Exception: # may need to use a more specific exception |
| 187 | logger.warning('Unable to symlink %r to %r', src, dst) |
| 188 | force_copy = True |
| 189 | if force_copy: |
| 190 | shutil.copyfile(src, dst) |
| 191 | |
| 192 | def setup_python(self, context): |
| 193 | """ |
| 194 | Set up a Python executable in the environment. |
| 195 | |
| 196 | :param context: The information for the environment creation request |
| 197 | being processed. |
| 198 | """ |
| 199 | binpath = context.bin_path |
| 200 | exename = context.python_exe |
| 201 | path = context.env_exe |
| 202 | copier = self.symlink_or_copy |
| 203 | copier(context.executable, path) |
| 204 | dirname = context.python_dir |
| 205 | if os.name != 'nt': |
| 206 | if not os.path.islink(path): |
| 207 | os.chmod(path, 0o755) |
Vinay Sajip | 4469746 | 2012-05-28 16:33:01 +0100 | [diff] [blame] | 208 | for suffix in ('python', 'python3'): |
| 209 | path = os.path.join(binpath, suffix) |
| 210 | if not os.path.exists(path): |
| 211 | os.symlink(exename, path) |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 212 | else: |
| 213 | subdir = 'DLLs' |
| 214 | include = self.include_binary |
| 215 | files = [f for f in os.listdir(dirname) if include(f)] |
| 216 | for f in files: |
| 217 | src = os.path.join(dirname, f) |
| 218 | dst = os.path.join(binpath, f) |
| 219 | if dst != context.env_exe: # already done, above |
| 220 | copier(src, dst) |
| 221 | dirname = os.path.join(dirname, subdir) |
| 222 | if os.path.isdir(dirname): |
| 223 | files = [f for f in os.listdir(dirname) if include(f)] |
| 224 | for f in files: |
| 225 | src = os.path.join(dirname, f) |
| 226 | dst = os.path.join(binpath, f) |
| 227 | copier(src, dst) |
| 228 | # copy init.tcl over |
| 229 | for root, dirs, files in os.walk(context.python_dir): |
| 230 | if 'init.tcl' in files: |
| 231 | tcldir = os.path.basename(root) |
| 232 | tcldir = os.path.join(context.env_dir, 'Lib', tcldir) |
| 233 | os.makedirs(tcldir) |
| 234 | src = os.path.join(root, 'init.tcl') |
| 235 | dst = os.path.join(tcldir, 'init.tcl') |
| 236 | shutil.copyfile(src, dst) |
| 237 | break |
| 238 | |
| 239 | def setup_scripts(self, context): |
| 240 | """ |
| 241 | Set up scripts into the created environment from a directory. |
| 242 | |
| 243 | This method installs the default scripts into the environment |
| 244 | being created. You can prevent the default installation by overriding |
| 245 | this method if you really need to, or if you need to specify |
| 246 | a different location for the scripts to install. By default, the |
| 247 | 'scripts' directory in the venv package is used as the source of |
| 248 | scripts to install. |
| 249 | """ |
| 250 | path = os.path.abspath(os.path.dirname(__file__)) |
| 251 | path = os.path.join(path, 'scripts') |
| 252 | self.install_scripts(context, path) |
| 253 | |
| 254 | def post_setup(self, context): |
| 255 | """ |
| 256 | Hook for post-setup modification of the venv. Subclasses may install |
| 257 | additional packages or scripts here, add activation shell scripts, etc. |
| 258 | |
| 259 | :param context: The information for the environment creation request |
| 260 | being processed. |
| 261 | """ |
| 262 | pass |
| 263 | |
| 264 | def replace_variables(self, text, context): |
| 265 | """ |
| 266 | Replace variable placeholders in script text with context-specific |
| 267 | variables. |
| 268 | |
| 269 | Return the text passed in , but with variables replaced. |
| 270 | |
| 271 | :param text: The text in which to replace placeholder variables. |
| 272 | :param context: The information for the environment creation request |
| 273 | being processed. |
| 274 | """ |
| 275 | text = text.replace('__VENV_DIR__', context.env_dir) |
| 276 | text = text.replace('__VENV_NAME__', context.prompt) |
| 277 | text = text.replace('__VENV_BIN_NAME__', context.bin_name) |
| 278 | text = text.replace('__VENV_PYTHON__', context.env_exe) |
| 279 | return text |
| 280 | |
| 281 | def install_scripts(self, context, path): |
| 282 | """ |
| 283 | Install scripts into the created environment from a directory. |
| 284 | |
| 285 | :param context: The information for the environment creation request |
| 286 | being processed. |
| 287 | :param path: Absolute pathname of a directory containing script. |
| 288 | Scripts in the 'common' subdirectory of this directory, |
| 289 | and those in the directory named for the platform |
| 290 | being run on, are installed in the created environment. |
| 291 | Placeholder variables are replaced with environment- |
| 292 | specific values. |
| 293 | """ |
| 294 | binpath = context.bin_path |
| 295 | plen = len(path) |
| 296 | for root, dirs, files in os.walk(path): |
| 297 | if root == path: # at top-level, remove irrelevant dirs |
| 298 | for d in dirs[:]: |
| 299 | if d not in ('common', os.name): |
| 300 | dirs.remove(d) |
| 301 | continue # ignore files in top level |
| 302 | for f in files: |
| 303 | srcfile = os.path.join(root, f) |
| 304 | suffix = root[plen:].split(os.sep)[2:] |
| 305 | if not suffix: |
| 306 | dstdir = binpath |
| 307 | else: |
| 308 | dstdir = os.path.join(binpath, *suffix) |
| 309 | if not os.path.exists(dstdir): |
| 310 | os.makedirs(dstdir) |
| 311 | dstfile = os.path.join(dstdir, f) |
| 312 | with open(srcfile, 'rb') as f: |
| 313 | data = f.read() |
| 314 | if srcfile.endswith('.exe'): |
| 315 | mode = 'wb' |
| 316 | else: |
| 317 | mode = 'w' |
Vinay Sajip | bdd13fd | 2012-10-28 12:39:39 +0000 | [diff] [blame] | 318 | try: |
| 319 | data = data.decode('utf-8') |
| 320 | data = self.replace_variables(data, context) |
| 321 | except UnicodeDecodeError as e: |
| 322 | data = None |
| 323 | logger.warning('unable to copy script %r, ' |
| 324 | 'may be binary: %s', srcfile, e) |
| 325 | if data is not None: |
| 326 | with open(dstfile, mode) as f: |
| 327 | f.write(data) |
| 328 | shutil.copymode(srcfile, dstfile) |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 329 | |
| 330 | |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 331 | def create(env_dir, system_site_packages=False, clear=False, symlinks=False): |
| 332 | """ |
| 333 | Create a virtual environment in a directory. |
| 334 | |
Vinay Sajip | 87ed599 | 2012-11-14 11:18:35 +0000 | [diff] [blame] | 335 | By default, makes the system (global) site-packages dir *un*available to |
| 336 | the created environment, and uses copying rather than symlinking for files |
| 337 | obtained from the source Python installation. |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 338 | |
| 339 | :param env_dir: The target directory to create an environment in. |
| 340 | :param system_site_packages: If True, the system (global) site-packages |
| 341 | dir is available to the environment. |
| 342 | :param clear: If True and the target directory exists, it is deleted. |
| 343 | Otherwise, if the target directory exists, an error is |
| 344 | raised. |
| 345 | :param symlinks: If True, attempt to symlink rather than copy files into |
| 346 | virtual environment. |
| 347 | """ |
Vinay Sajip | 4469746 | 2012-05-28 16:33:01 +0100 | [diff] [blame] | 348 | builder = EnvBuilder(system_site_packages=system_site_packages, |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 349 | clear=clear, symlinks=symlinks) |
| 350 | builder.create(env_dir) |
| 351 | |
| 352 | def main(args=None): |
| 353 | compatible = True |
| 354 | if sys.version_info < (3, 3): |
| 355 | compatible = False |
| 356 | elif not hasattr(sys, 'base_prefix'): |
| 357 | compatible = False |
| 358 | if not compatible: |
Vinay Sajip | 2895244 | 2012-06-25 00:47:46 +0100 | [diff] [blame] | 359 | raise ValueError('This script is only for use with Python 3.3') |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 360 | else: |
| 361 | import argparse |
| 362 | |
| 363 | parser = argparse.ArgumentParser(prog=__name__, |
| 364 | description='Creates virtual Python ' |
| 365 | 'environments in one or ' |
| 366 | 'more target ' |
Vinay Sajip | 4d378d8 | 2012-07-08 17:50:42 +0100 | [diff] [blame] | 367 | 'directories.', |
| 368 | epilog='Once an environment has been ' |
| 369 | 'created, you may wish to ' |
| 370 | 'activate it, e.g. by ' |
| 371 | 'sourcing an activate script ' |
| 372 | 'in its bin directory.') |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 373 | parser.add_argument('dirs', metavar='ENV_DIR', nargs='+', |
| 374 | help='A directory to create the environment in.') |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 375 | parser.add_argument('--system-site-packages', default=False, |
| 376 | action='store_true', dest='system_site', |
Vinay Sajip | 4469746 | 2012-05-28 16:33:01 +0100 | [diff] [blame] | 377 | help='Give the virtual environment access to the ' |
| 378 | 'system site-packages dir.') |
Vinay Sajip | 90db661 | 2012-07-17 17:33:46 +0100 | [diff] [blame] | 379 | if os.name == 'nt': |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 380 | use_symlinks = False |
| 381 | else: |
| 382 | use_symlinks = True |
| 383 | parser.add_argument('--symlinks', default=use_symlinks, |
| 384 | action='store_true', dest='symlinks', |
Vinay Sajip | 4d378d8 | 2012-07-08 17:50:42 +0100 | [diff] [blame] | 385 | help='Try to use symlinks rather than copies, ' |
| 386 | 'when symlinks are not the default for ' |
| 387 | 'the platform.') |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 388 | parser.add_argument('--clear', default=False, action='store_true', |
Vinay Sajip | bd40d3e | 2012-10-11 17:22:45 +0100 | [diff] [blame] | 389 | dest='clear', help='Delete the contents of the ' |
| 390 | 'environment directory if it ' |
| 391 | 'already exists, before ' |
| 392 | 'environment creation.') |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 393 | parser.add_argument('--upgrade', default=False, action='store_true', |
| 394 | dest='upgrade', help='Upgrade the environment ' |
| 395 | 'directory to use this version ' |
Vinay Sajip | 4221142 | 2012-05-26 20:36:12 +0100 | [diff] [blame] | 396 | 'of Python, assuming Python ' |
| 397 | 'has been upgraded in-place.') |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 398 | options = parser.parse_args(args) |
| 399 | if options.upgrade and options.clear: |
| 400 | raise ValueError('you cannot supply --upgrade and --clear together.') |
Vinay Sajip | 4469746 | 2012-05-28 16:33:01 +0100 | [diff] [blame] | 401 | builder = EnvBuilder(system_site_packages=options.system_site, |
| 402 | clear=options.clear, symlinks=options.symlinks, |
| 403 | upgrade=options.upgrade) |
Vinay Sajip | 7ded1f0 | 2012-05-26 03:45:29 +0100 | [diff] [blame] | 404 | for d in options.dirs: |
| 405 | builder.create(d) |
| 406 | |
| 407 | if __name__ == '__main__': |
| 408 | rc = 1 |
| 409 | try: |
| 410 | main() |
| 411 | rc = 0 |
| 412 | except Exception as e: |
| 413 | print('Error: %s' % e, file=sys.stderr) |
| 414 | sys.exit(rc) |