通过互联网/多种协议导入python模块或动态创建模块 [英] Import python module over the internet/multiple protocols or dynamically create module

问题描述

是否可以使用http(s)，ftp，smb或任何其他协议从互联网上通过import一个Python模块?如果是这样，怎么办?如果没有，为什么?

Is it possible to import a Python module from over the internet using the http(s), ftp, smb or any other protocol? If so, how? If not, why?

我想这是关于让Python使用更多一种协议(读取文件系统)并使它也能使用其他协议.是的，我同意它会慢很多倍，但是一定的优化和更大的未来带宽肯定会平衡它.

I guess it's about making Python use more the one protocol(reading the filesystem) and enabling it to use others as well. Yes I agree it would be many folds slower, but some optimization and larger future bandwidths would certainly balance it out.

例如:

import site

site.addsitedir("https://bitbucket.org/zzzeek/sqlalchemy/src/e8167548429b9d4937caaa09740ffe9bdab1ef61/lib")

import sqlalchemy
import sqlalchemy.engine

推荐答案

原则上可以，但是所有支持此功能的内置工具都通过文件系统.

In principle, yes, but all of the tools built-in which kinda support this go through the filesystem.

为此，您将必须从任何地方加载源，使用compile进行编译，并使用新模块的__dict__进行编译.见下文.

To do this, you're going to have to load the source from wherever, compile it with compile, and exec it with the __dict__ of a new module. See below.

我已经离开了实际上从互联网上获取的文本，并解析了uris等作为读者的练习(对于初学者:我建议使用requests)

I have left the actually grabbing text from the internet, and parsing uris etc as an exercise for the reader (for beginners: I suggest using requests)

在 pep 302 术语中，这将是功能(参数不同).有关如何将其与import语句集成的详细信息，请参见该文档.

In pep 302 terms, this would be the implementation behind a loader.load_module function (the parameters are different). See that document for details on how to integrate this with the import statement.

import imp
modulesource = 'a=1;b=2' #load from internet or wherever
def makemodule(modulesource,sourcestr='http://some/url/or/whatever',modname=None):
    #if loading from the internet, you'd probably want to parse the uri, 
    # and use the last part as the modulename. It'll come up in tracebacks
    # and the like.
    if not modname: modname = 'newmodulename'
    #must be exec mode
    # every module needs a source to be identified, can be any value
    # but if loading from the internet, you'd use the URI
    codeobj = compile(modulesource, sourcestr, 'exec')
    newmodule = imp.new_module(modname)
    exec(codeobj,newmodule.__dict__)
    return newmodule
newmodule = makemodule(modulesource)
print(newmodule.a)

此时，newmodule已经是作用域中的模块对象，因此您无需导入它或任何其他内容.

At this point newmodule is already a module object in scope, so you don't need to import it or anything.

modulesource = '''
a = 'foo'
def myfun(astr):
    return a + astr
'''
newmod = makemodule(modulesource)
print(newmod.myfun('bat'))

此处的IDONE: http://ideone.com/dXGziO

经python 2测试，应与python 3一起使用(使用文本兼容的打印；使用类似函数的exec语法).

Tested with python 2, should work with python 3 (textually compatible print used;function-like exec syntax used).

这篇关于通过互联网/多种协议导入python模块或动态创建模块的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！