python - 刚开始编写 Fabric 文件来安装包

Question

from fabric.api import sudo, put, run

def install():
    run('source /home/user/.virtualenvs/demo/bin/activate')
    run('pip install requests')

if __name__ == '__main__':
    install()
# to run this, do fab fabfile

Q1。 我想在那个环境中安装 pip 。但脚本运行后，requests 并未安装在 virtualenv 中。为什么？

第二季度。要求我提供主机信息(以下也是Q1的日志)。如果我的目标是在本地运行，是否有更好的方法来处理这个问题？

No hosts found. Please specify (single) host string for connection: localhost
[localhost] run: source /home/user/.virtualenvs/demo/bin/activate
[localhost] Passphrase for private key: 
[localhost] Login password: 
[localhost] run: pip install requests
[localhost] out: Requirement already satisfied (use --upgrade to upgrade): requests in /usr/local/lib/python2.7/dist-packages
[localhost] out: Requirement already satisfied (use --upgrade to upgrade): certifi>=0.0.7 in /usr/local/lib/python2.7/dist-packages (from requests)
[localhost] out: Requirement already satisfied (use --upgrade to upgrade): oauthlib>=0.1.0,<0.2.0 in /usr/local/lib/python2.7/dist-packages (from requests)
[localhost] out: Requirement already satisfied (use --upgrade to upgrade): chardet>=1.0.0 in /usr/lib/python2.7/dist-packages (from requests)
[localhost] out: Requirement already satisfied (use --upgrade to upgrade): rsa in /usr/local/lib/python2.7/dist-packages (from oauthlib>=0.1.0,<0.2.0->requests)
[localhost] out: Requirement already satisfied (use --upgrade to upgrade): pyasn1>=0.0.13 in /usr/local/lib/python2.7/dist-packages (from rsa->oauthlib>=0.1.0,<0.2.0->requests)
[localhost] out: Cleaning up...
[localhost] out: 

<小时/>

更新

我可以通过一个 run 命令安装这些软件包。有更好的方法吗？

谢谢。

<小时/>

这是更新代码:

from fabric.api import sudo, put, run
from fabric.context_managers import prefix

def install():
    with prefix('source /home/user/.virtualenvs/demo/bin/activate'):
        run('pip install requests')

if __name__ == '__main__':
    install()

http://docs.fabfile.org/en/1.2.0/api/core/context_managers.html?highlight=prefix#fabric.context_managers.prefix

Answer 1

每个fabric.run命令都会生成一个单独的子shell，在其中执行该命令。

如果您在其中一个运行命令中激活 virtualenv，则该环境不可用于单独调用运行命令中的后续命令执行。

请参阅 stackoverflow 上的以下讨论以获取正确的解决方案:

• Activate a virtualenv via fabric as deploy user

检查 contextmanager 的用法，以在激活 virtualenv 的情况下运行命令。