python自动使用虚拟环境和安装依赖
代码如下，Windows环境测试通过（1. 判断是否在虚拟环境里；2. 判断当前目录下是否有venv文件夹；3. 如果都没有则通过python -m venv venv来创建；4. 然后调用venv里的pip来安装模块）
1 import platform 2 import re 3 import subprocess 4 import sys 5 from contextlib import AbstractContextManager 6 from pathlib import Path 7 8 9 class EnsureImport(AbstractContextManager): 10 """Auto install modules if import error. 11 12 Usage:: 13 >>> for _ range(EnsureImport.retry): 14 ... with EnsureImport( 15 ... multipart='python-multipart', dotenv='python-dotenv' 16 ... ) as _m: 17 ... import six 18 ... import multipart 19 ... from dotenv import load_dotenv 20 ... # more imports ... 21 ... if _m.ok: 22 ... break 23 ... 24 """ 25 26 mapping = { 27 "multipart": "python-multipart", 28 "dotenv": "python-dotenv", 29 "snap7": "python-snap7", 30 } 31 retry = 30 32 33 def __init__(self, **kwargs): 34 self.exception = None 35 self._success = True 36 self.package_mapping = dict(self.mapping, **kwargs) 37 38 @property 39 def ok(self) -> bool: 40 return self._success 41 42 def __exit__(self, exc_type, exc_value, traceback): 43 if isinstance(exc_value, (ImportError, ModuleNotFoundError)): 44 self.exception = exc_value 45 self._success = False 46 self.run() 47 return True 48 49 def run(self): 50 e = self.exception 51 modules = re.findall(r"'([a-zA-Z][0-9a-zA-Z_-]+)'", str(e)) 52 if "--no-install" in sys.argv or not modules: 53 raise e 54 ms = (self.package_mapping.get(i, i) for i in modules) 55 rc = self.install_and_extend_sys_path(*ms) 56 if rc: 57 sys.exit(rc) 58 59 @staticmethod 60 def is_venv() -> bool: 61 """Whether in a virtual environment(also work for poetry)""" 62 return hasattr(sys, "real_prefix") or ( 63 hasattr(sys, "base_prefix") and sys.base_prefix != sys.prefix 64 ) 65 66 @staticmethod 67 def run_and_echo(cmd: str) -> int: 68 print("-->\n", cmd, flush=True) 69 return subprocess.call(cmd, shell=True) 70 71 @staticmethod 72 def log_error(action: str) -> None: 73 print(f"ERROR: failed to {action}") 74 75 @classmethod 76 def install_and_extend_sys_path(cls, *packages) -> int: 77 py = Path(sys.executable) 78 depends = " ".join(packages) 79 if not cls.is_venv(): 80 p = Path.cwd() / "venv" 81 if not p.exists(): 82 if cls.run_and_echo(f"{py} -m venv venv"): 83 cls.log_error(f"create virtual environment for {py}") 84 return 1 85 if platform.platform().lower().startswith("win"): 86 py = p / "Scripts" / "python.exe" 87 else: 88 py = p / "bin/python" 89 cls.run_and_echo(f"{py} -m pip install --upgrade pip") 90 lib = list(p.rglob("site-packages"))[0] 91 sys.path.append(lib.as_posix()) 92 if cls.run_and_echo(f"{py} -m pip install {depends}"): 93 cls.log_error(f"install {depends}") 94 return 2 95 return 0 96 97 98 for _ in range(EnsureImport.retry): 99 with EnsureImport(dotenv='python-dotenv') as _f: 100 from dotenv import load_dotenv 101 if _f.ok: 102 break 103 104 105 load_dotenv()
#######################
以下为旧版代码，可以不用看
#######################
import os
import platform
import re
import sys
from pathlib import Path
def is_venv() -> bool:
"""判断是否处于虚拟环境(也适用于poetry的)"""
if hasattr(sys, "real_prefix"):
return True
return hasattr(sys, "base_prefix") and sys.base_prefix != sys.prefix
def run_and_echo(cmd) -> int:
print("-->\n", cmd, flush=True)
return os.system(cmd)
def install_and_rerun(*packages):
py = Path(sys.executable)
if not is_venv():
if not (p := Path("venv")).exists():
if run_and_echo(f"{py} -m venv venv"):
return 1
if platform.platform().lower().startswith("win"):
py = p / "Scripts" / "python.exe"
else:
py = p / "bin/python"
if run_and_echo(f"{py} -m pip install {' '.join(packages)}"):
return 2
cmd = f"{py} {sys.argv[0]} --no-install {' '.join(sys.argv[1:])}"
return run_and_echo(cmd)
try:
import kivy
except ImportError as e:
if "--no-install" in sys.argv:
raise e
modules = re.findall(r"'([a-zA-Z_-]+)'", str(e))
sys.exit(install_and_rerun(*modules))
def main():
pass
if __name__ == '__main__':
main()
运行时，如果import失败，会判断是否处于虚拟环境，是的话，直接pip install报错的缺失包，然后自动重新执行脚本;
否则，判断当前路径是否有venv文件，有的话使用venv/*/python，否则使用python -m venv venv创建它
优化成class以便PyCharm可以折叠
import os
import platform
import random
import re
import sys
from pathlib import Path
class EnsureImport:
def __init__(self, e):
self.exception = e
def run(self):
e = self.exception
if "--no-install" in sys.argv:
raise e
modules = re.findall(r"'([a-zA-Z_-]+)'", str(e))
sys.exit(self.install_and_rerun(*modules))
@staticmethod
def is_venv() -> bool:
"""判断是否处于虚拟环境(也适用于poetry的)"""
if hasattr(sys, "real_prefix"):
return True
return hasattr(sys, "base_prefix") and sys.base_prefix != sys.prefix
@staticmethod
def run_and_echo(cmd) -> int:
print("-->\n", cmd, flush=True)
return os.system(cmd)
@classmethod
def install_and_rerun(cls, *packages):
py = Path(sys.executable)
command = " ".join(sys.argv)
if not cls.is_venv():
if not (p := Path("venv")).exists():
if cls.run_and_echo(f"{py} -m venv venv"):
return 1
else:
cls.run_and_echo(f'{py} -m pip install -U pip')
if platform.platform().lower().startswith("win"):
py = p / "Scripts" / "python.exe"
else:
py = p / "bin/python"
return cls.run_and_echo(f"{py} {command}")
depends = " ".join(packages)
if cls.run_and_echo(f"{py} -m pip install {depends}"):
return 2
cmd = f"{py} {command} --no-install"
return cls.run_and_echo(cmd)
try:
import dearpygui.dearpygui as dpg
except ImportError as e:
EnsureImport(e).run()
def main():
print(dpg)
if __name__ == "__main__":
main()
使用了isort+black+ruff进行代码格式化
进一步优化成with风格：
import os
import platform
import re
import sys
from pathlib import Path
class EnsureImport:
"""Auto install module if import error.
Usage::
>>> with EnsureImport():
... import six
"""
def __init__(self):
self.exception = None
def __enter__(self):
return self
def __exit__(self, exc_type, exc_value, traceback):
if exc_type is not None:
if isinstance(exc_value, (ImportError, ModuleNotFoundError)):
self.exception = exc_value
self.run()
def run(self):
e = self.exception
if "--no-install" in sys.argv:
raise e
modules = re.findall(r"'([a-zA-Z_-]+)'", str(e))
sys.exit(self.install_and_rerun(*modules))
@staticmethod
def is_venv() -> bool:
"""判断是否处于虚拟环境(也适用于poetry的)"""
if hasattr(sys, "real_prefix"):
return True
return hasattr(sys, "base_prefix") and sys.base_prefix != sys.prefix
@staticmethod
def run_and_echo(cmd) -> int:
print("-->\n", cmd, flush=True)
return os.system(cmd)
@classmethod
def install_and_rerun(cls, *packages):
py = Path(sys.executable)
command = " ".join(sys.argv)
if not cls.is_venv():
if not (p := Path("venv")).exists():
if cls.run_and_echo(f"{py} -m venv venv"):
return 1
if platform.platform().lower().startswith("win"):
py = p / "Scripts" / "python.exe"
else:
py = p / "bin/python"
return cls.run_and_echo(f"{py} {command}")
depends = " ".join(packages)
if cls.run_and_echo(f"{py} -m pip install {depends}"):
return 2
cmd = f"{py} {command} --no-install"
return cls.run_and_echo(cmd)
with EnsureImport():
import six
def main():
print(six.__file__)
if __name__ == "__main__":
main()
进一步优化成支持多import且只run一次的：
import platform
import re
import subprocess
import sys
from contextlib import AbstractContextManager
from pathlib import Path
class EnsureImport(AbstractContextManager):
"""Auto install modules if import error.
Usage::
>>> for _ range(EnsureImport.retry):
... with EnsureImport(
... multipart='python-multipart', dotenv='python-dotenv'
... ) as _m:
... import six
... import multipart
... from dotenv import load_dotenv
... # more imports ...
... if _m.ok:
... break
...
"""
retry = 10
def __init__(self, **kwargs):
self.exception = None
self._success = True
self.package_mapping = kwargs
@property
def ok(self) -> bool:
return self._success
def __exit__(self, exc_type, exc_value, traceback):
if isinstance(exc_value, (ImportError, ModuleNotFoundError)):
self.exception = exc_value
self._success = False
self.run()
return True
def run(self):
e = self.exception
if "--no-install" in sys.argv:
raise e
modules = re.findall(r"'([a-zA-Z_-]+)'", str(e))
if mp := self.package_mapping:
modules = [mp.get(i, i) for i in modules]
if rc := self.install_and_extend_sys_path(*modules):
sys.exit(rc)
@staticmethod
def is_venv() -> bool:
"""判断是否处于虚拟环境(也适用于poetry的)"""
if hasattr(sys, "real_prefix"):
return True
return hasattr(sys, "base_prefix") and sys.base_prefix != sys.prefix
@staticmethod
def run_and_echo(cmd: str) -> int:
print("-->\n", cmd, flush=True)
return subprocess.call(cmd, shell=True)
@staticmethod
def log_error(action: str) -> None:
print(f"ERROR: failed to {action}")
@classmethod
def install_and_extend_sys_path(cls, *packages) -> int:
py = Path(sys.executable)
depends = " ".join(packages)
if not cls.is_venv():
if not (p := Path("venv")).exists():
if depends.lower() == 'dearpygui' and sys.version_info >= (3, 11):
py = Path('python3.10')
if cls.run_and_echo(f"{py} -m venv venv"):
cls.log_error(f"create virtual environment for {py}")
return 1
if platform.platform().lower().startswith("win"):
py = p / "Scripts" / "python.exe"
else:
py = p / "bin/python"
lib = list(p.rglob("site-packages"))[0]
sys.path.append(lib.as_posix())
if cls.run_and_echo(f"{py} -m pip install {depends}"):
cls.log_error(f"install {depends}")
return 2
return 0
for _ in range(EnsureImport.retry):
with EnsureImport(multipart="python-multipart", dotenv="python-dotenv") as _m:
import multipart
import six
from dotenv import load_dotenv
if _m.ok:
break
def main():
print(six.__file__)
print(multipart.__file__)
load_dotenv()
if __name__ == "__main__":
main()
