svn2svn源码学习笔记01

#coding:utf-8
from subprocess import Popen, PIPE
import locale,os
locale_encoding = locale.getpreferredencoding()
def run_svn(args,fail_if_stderr=False,encoding="utf-8"):
    #内部函数以_开头，一般应用于map filter等运算符
    def _transform_data(a):
        if isinstance(a, unicode):
            a = a.encode(encoding or locale_encoding)
        elif not isinstance(a, str):
            a = str(a)
        return a
    def _shell_quote(s):
        if os.name == "nt":
            q = '"'
        else:
            q = "'"
        return q + s.replace('\\', '\\\\').replace("'", "'\"'\"'") + q
    t_args = map(_transform_data, args)
    cmd = "svn"
    cmd_string = str(" ".join(map(_shell_quote, [cmd] + t_args)))
    pipe = Popen([cmd] + t_args,executable = cmd,stdout = PIPE,stderr=PIPE)
    out,err = pipe.communicate()
    return out

"""
1.如何对一个变量进行encode处理即将一个unicode类型的字符转义成utf-8或gbk
if isinstance(a,unicode):
   a = a.encoding("utf-8",locale.getpreferredencoding())
elif not isinstance(a,str):
    a = str(a)
return a
2.如何能够利用子函数里面应用于map filter等函数操作
def _transform(a)
map(_transform,args)

"""
"""
解析SVN 输出的XML字符串信息输出到一个字典数据
"""
def parse_svn_info_xml(xml_string):
    try:
        from xml.etree import cElementTree as ET
    except ImportError:
        try:
            from xml.etree import ElementTree as ET
        except ImportError:
            try:
                import cElementTree as ET
            except ImportError:
                from elementtree import ElementTree as ET
    d = {}
    tree = ET.fromstring(xml_string)
    entry = tree.find(".//entry")
    if entry:
        d['url'] = entry.find("url").text
        d['revision'] = entry.find("revision").text
        d['repos_url'] = entry.find("repos_url").text
        d['last_changed_rev'] = entry.find("last_changed_rev").text
        d['kind'] = entry.find("kind").text
    return d

1. 函数里面套函数应用
2. map filter等应用
3. 字典的妙用