werkzeug/routing.py-Rule源码分析

Rule类主要用来定义和表示一个URL的模式。主要定义了一些关键字参数，用来改变url的行为。例如：这个url可以接收的请求方法，url的子域名，默认路径，端点名称，是否强制有斜杠在末尾等等

在最开始使用route()传递的option参数，最后都是传给了Rule这个类来处理的

class Rule(RuleFactory):
    def __init__(self, string, defaults=None, subdomain=None, methods=None,
                 build_only=False, endpoint=None, strict_slashes=None,
                 redirect_to=None, alias=False, host=None):
        if not string.startswith('/'):
            raise ValueError('urls must start with a leading slash')
        self.rule = string
        self.is_leaf = not string.endswith('/')

        self.map = None
        self.strict_slashes = strict_slashes
        self.subdomain = subdomain
        self.host = host
        self.defaults = defaults
        self.build_only = build_only
        self.alias = alias
        if methods is None:
            self.methods = None
        else:
            if isinstance(methods, str):
                raise TypeError('param `methods` should be `Iterable[str]`, not `str`')
            self.methods = set([x.upper() for x in methods])
            if 'HEAD' not in self.methods and 'GET' in self.methods:
                self.methods.add('HEAD')
        self.endpoint = endpoint
        self.redirect_to = redirect_to

        if defaults:
            self.arguments = set(map(str, defaults))
        else:
            self.arguments = set()
        self._trace = self._converters = self._regex = self._argument_weights = None

源代码