| import itertools |
| import re |
| import types |
| |
| from .logger import get_logger |
| |
| any_method = object() |
| |
| class RouteTokenizer(object): |
| def literal(self, scanner, token): |
| return ("literal", token) |
| |
| def slash(self, scanner, token): |
| return ("slash", None) |
| |
| def group(self, scanner, token): |
| return ("group", token[1:-1]) |
| |
| def star(self, scanner, token): |
| return ("star", token[1:-3]) |
| |
| def scan(self, input_str): |
| scanner = re.Scanner([(r"/", self.slash), |
| (r"{\w*}", self.group), |
| (r"\*", self.star), |
| (r"(?:\\.|[^{\*/])*", self.literal),]) |
| return scanner.scan(input_str) |
| |
| class RouteCompiler(object): |
| def __init__(self): |
| self.reset() |
| |
| def reset(self): |
| self.star_seen = False |
| |
| def compile(self, tokens): |
| self.reset() |
| |
| func_map = {"slash":self.process_slash, |
| "literal":self.process_literal, |
| "group":self.process_group, |
| "star":self.process_star} |
| |
| re_parts = ["^"] |
| |
| if not tokens or tokens[0][0] != "slash": |
| tokens = itertools.chain([("slash", None)], tokens) |
| |
| for token in tokens: |
| re_parts.append(func_map[token[0]](token)) |
| |
| if self.star_seen: |
| re_parts.append(")") |
| re_parts.append("$") |
| |
| return re.compile("".join(re_parts)) |
| |
| def process_literal(self, token): |
| return re.escape(token[1]) |
| |
| def process_slash(self, token): |
| return "/" |
| |
| def process_group(self, token): |
| if self.star_seen: |
| raise ValueError("Group seen after star in regexp") |
| return "(?P<%s>[^/]+)" % token[1] |
| |
| def process_star(self, token): |
| if self.star_seen: |
| raise ValueError("Star seen after star in regexp") |
| self.star_seen = True |
| return "(.*" |
| |
| def compile_path_match(route_pattern): |
| """tokens: / or literal or match or *""" |
| |
| tokenizer = RouteTokenizer() |
| tokens, unmatched = tokenizer.scan(route_pattern) |
| |
| assert unmatched == "", unmatched |
| |
| compiler = RouteCompiler() |
| |
| return compiler.compile(tokens) |
| |
| class Router(object): |
| """Object for matching handler functions to requests. |
| |
| :param doc_root: Absolute path of the filesystem location from |
| which to serve tests |
| :param routes: Initial routes to add; a list of three item tuples |
| (method, path_pattern, handler_function), defined |
| as for register() |
| """ |
| |
| def __init__(self, doc_root, routes): |
| self.doc_root = doc_root |
| self.routes = [] |
| self.logger = get_logger() |
| for route in reversed(routes): |
| self.register(*route) |
| |
| def register(self, methods, path, handler): |
| """Register a handler for a set of paths. |
| |
| :param methods: Set of methods this should match. "*" is a |
| special value indicating that all methods should |
| be matched. |
| |
| :param path_pattern: Match pattern that will be used to determine if |
| a request path matches this route. Match patterns |
| consist of either literal text, match groups, |
| denoted {name}, which match any character except /, |
| and, at most one \*, which matches and character and |
| creates a match group to the end of the string. |
| If there is no leading "/" on the pattern, this is |
| automatically implied. For example:: |
| |
| api/{resource}/*.json |
| |
| Would match `/api/test/data.json` or |
| `/api/test/test2/data.json`, but not `/api/test/data.py`. |
| |
| The match groups are made available in the request object |
| as a dictionary through the route_match property. For |
| example, given the route pattern above and the path |
| `/api/test/data.json`, the route_match property would |
| contain:: |
| |
| {"resource": "test", "*": "data.json"} |
| |
| :param handler: Function that will be called to process matching |
| requests. This must take two parameters, the request |
| object and the response object. |
| |
| """ |
| if type(methods) in types.StringTypes or methods in (any_method, "*"): |
| methods = [methods] |
| for method in methods: |
| self.routes.append((method, compile_path_match(path), handler)) |
| self.logger.debug("Route pattern: %s" % self.routes[-1][1].pattern) |
| |
| def get_handler(self, request): |
| """Get a handler for a request or None if there is no handler. |
| |
| :param request: Request to get a handler for. |
| :rtype: Callable or None |
| """ |
| for method, regexp, handler in reversed(self.routes): |
| if (request.method == method or |
| method in (any_method, "*") or |
| (request.method == "HEAD" and method == "GET")): |
| m = regexp.match(request.url_parts.path) |
| if m: |
| if not hasattr(handler, "__class__"): |
| name = handler.__name__ |
| else: |
| name = handler.__class__.__name__ |
| self.logger.debug("Found handler %s" % name) |
| |
| match_parts = m.groupdict().copy() |
| if len(match_parts) < len(m.groups()): |
| match_parts["*"] = m.groups()[-1] |
| request.route_match = match_parts |
| |
| return handler |
| return None |