1 #coding=utf-8
   2 
   3 import re
   4 import sets
   5 import copy
   6 import types
   7 
   8 class T:
   9         def __init__(self, string):
  10                 self.text = string
  11                 
  12         def getText(self):
  13                 return self.text
  14         
  15 #定义模板处理类
  16 class Template:
  17         def __init__(self, beginchars='<#', endchars='#>'):
  18                 self.beginchars = beginchars            #define template var's left delimeter chars
  19                 self.endchars = endchars                        #define template var's right delimeter chars
  20         
  21         #装入模板
  22         def load(self, tplname):
  23                 mod = __import__(tplname)
  24                 components = tplname.split('.')
  25                 for comp in components[1:]:
  26                         mod = getattr(mod, comp)
  27 
  28                 self.vars = {}
  29                 self.nodes = {}
  30                 for vn in dir(mod):
  31                         v = getattr(mod, vn)
  32                         if hasattr(v, '__class__') and v.__class__.__name__ == 'T':
  33                                 self.vars[vn] = v
  34                                 self.nodes[vn] = self._get_rely_on_node(v.getText())
  35                                 
  36         def _getPattern(self):
  37                 return r'%s(\w+)%s' % (self.beginchars, self.endchars)
  38 
  39         #取模板元素的相关集
  40         def _get_rely_on_node(self, s): #search for %(name)s format, make a dict
  41                 re_node = re.compile(self._getPattern())
  42 
  43                 return list(sets.Set(re_node.findall(s)))
  44                 
  45         #取模板元素的替换顺序
  46         def _get_list(self, path, target):
  47                 if not self.vars.has_key(target):
  48                         return
  49                 if target not in path:
  50                         path.append(target)
  51                 for i in self.nodes[target]:
  52                         self._get_list(path, i)
  53                 return
  54 
  55         #生成模板值
  56         #values应为字典的字典。即每一个模板元素如果引用有外部的变量，那么在values中应有此模板元素的一个键。
  57         #同时它的值应为所有外部变量的一个字典
  58         def value(self, target='main', values=None):
  59                 path = []
  60                 self._get_list(path, target)
  61                 path.reverse()
  62                 vals = {}
  63                 for i in path:
  64                         value = self._getElementValue(i, vals, values)
  65                         vals[i] = value
  66                 return vals[target]
  67         
  68         #把一段文件本的可替换信息使用values中的变量进行替换
  69         #text是段字符串
  70         #values是一个对应替换信息的字典
  71         def _replace(self, text, values):
  72                 def dosup(matchobj, values=values):
  73                         if values:
  74                                 return values.get(matchobj.groups()[0], matchobj.group())
  75                         else:
  76                                 return matchobj.group()
  77                 return re.sub(self._getPattern(), dosup, text)
  78                 
  79 
  80         #得到某个模板元素的替换值
  81         def _getElementValue(self, name, elements, values=None):
  82                 text = self.vars[name].getText()
  83                 #先将所有已经存在的模板元素进行替换
  84                 text = self._replace(text, elements)
  85                 #再根据外部引用变量的类型决定是否进行循环
  86                 if values and values.has_key(name):
  87                         if len(values[name]) == 1:
  88                                 text = self._replace(text, values[name])
  89                         else:
  90                                 s = []
  91                                 for v in values[name]:
  92                                         s.append(self._replace(text, v))
  93                                 text = ''.join(s)
  94                                 
  95                 return text
  96 
  97 if __name__ == '__main__':
  98         vars = dict(hello=[{'var':'var1'},{'var':'var2'},{'var':'var3'}])
  99         template = Template()
 100         template.load('tmp2')
 101         print template.value('program', vars)