为django写的一个source的tag

#coding=utf-8
from django importtemplate



register=template.Library()#register.tag('source', do_source)
@register.tag(name="source")defdo_source(parser, token):"""source can direct insert method return string into html

      {% source myapp mymethod %}

      or

      {% source myapp mymethod arg0 arg1 arg2 %}

      or

      {% source myapp mymethod arg0,arg1,arg2 %}"""
    try:#split_contents() knows not to split quoted strings.
        args =token.split_contents()exceptValueError:raise template.TemplateSyntaxError("%r tag requires at least two arguments" %token.contents.split()[0])if len(args) < 2:raise template.TemplateSyntaxError("%r tag requires at least two arguments" %token.contents.split()[0])

    model_name= args[1]

    method_name= args[2]

    params=[]if len(args) >=3:

        params+= args[3:]if len(params) == 1:if ',' inparams[0]:

            params= ['%s' % arg for arg in params[0].split(",")]#try to import this method
    try:

        models= __import__(model_name, fromlist =[method_name])

        method=getattr(models, method_name)except:raise template.TemplateSyntaxError("Can't import %s[%s]" %(model_name, method_name))returnSourceNode(method, params)classSourceNode(template.Node):def __init__(self, method, params):

        self.method=method

        self.params=paramsdefrender(self, context):try:

            value= self.method(context, (arg for arg inself.params))except:from django.conf importsettingsifsettings.DEBUG:importsys,traceback

                str= '<p> [%s] [%s] </p>' %(self.method, self.params)

                str+= '<p> [%s] </p>' % traceback.format_exception(*sys.exc_info())returnstrelse:returnstrreturn value