python - 使用Makefile安装pythonrequirements.txt仅更改requirements.txt

Question

仅当requirements.txt发生更改时，如何运行目标make install？

我不想每次执行make install时都升级软件包

我通过创建假文件 _requirements.txt.pyc 找到了一些解决方法，但它丑陋且肮脏。它将拒绝第二次安装pip需求，因为requirements.txt没有变化

$ make install-pip-requirements 
make: Nothing to be done for 'install-pip-requirements'.

但我的目标是:

# first time,
$ make install # create virtual environment, install requirements

# second time
$ make install # detected and skipping creating virtual env,
               # detect that requirements.txt have no changes 
               # and skipping installing again all python packages
make: Nothing to be done for 'install'.

Python 包看起来像:

.
├── Makefile
├── README.rst
├── lambda_handler.py
└── requirements.txt

我正在使用文件Makefile来实现Python中的一些自动化:

/opt/virtual_env:
    # create virtual env if folder not exists
    python -m venv /opt/virtual_env

virtual: /opt/virtual_env

# if requirements.txt is modified than execute pip install
_requirements.txt.pyc: requirements.txt
    /opt/virtual_env/bin/pip install -r --upgrade requirements.txt
    echo > _requirements.txt.pyc

requirements: SOME MAGIG OR SOME make flags        
    pip install -r requirements.txt

install-pip-requirements: _requirements.txt.pyc

install: virtual requirements

我确信

Must be a better way

这样做；)

Answer 1

@Andrei.Danciuc，make 只需要比较两个文件；您可以使用运行 pip install 的任何输出文件。

例如，我通常使用“vendored”文件夹，因此我可以为“vendored”文件夹的路径添加别名，而不是使用虚拟文件。

# Only run install if requirements.txt is newer than vendored folder
vendored-folder := vendored
.PHONY: install
install: $(vendored-folder)

$(vendored-folder): requirements.txt
    rm -rf $(vendored-folder)
    pip install -r requirements.txt -t $(vendored-folder)

如果您不使用供应商文件夹，下面的代码应该适用于 virtualenv 和全局设置。

# Only run install if requirements.txt is newer than SITE_PACKAGES location
.PHONY: install
SITE_PACKAGES := $(shell pip show pip | grep '^Location' | cut -f2 -d':')
install: $(SITE_PACKAGES)

$(SITE_PACKAGES): requirements.txt
    pip install -r requirements.txt