Adafruit_CircuitPython_HTTP.../adafruit_httpserver/route.py

131 lines
3.8 KiB
Python

# SPDX-FileCopyrightText: Copyright (c) 2022 Dan Halbert for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""
`adafruit_httpserver.route._HTTPRoute`
====================================================
* Author(s): Dan Halbert, Michał Pokusa
"""
try:
from typing import Callable, List, Union, Tuple
except ImportError:
pass
import re
from .methods import HTTPMethod
class _HTTPRoute:
"""Route definition for different paths, see `adafruit_httpserver.server.HTTPServer.route`."""
def __init__(self, path: str = "", method: HTTPMethod = HTTPMethod.GET) -> None:
contains_parameters = re.search(r"<\w*>", path) is not None
self.path = (
path if not contains_parameters else re.sub(r"<\w*>", r"([^/]*)", path)
)
self.method = method
self._contains_parameters = contains_parameters
def match(self, other: "_HTTPRoute") -> Tuple[bool, List[str]]:
"""
Checks if the route matches the other route.
If the route contains parameters, it will check if the ``other`` route contains values for
them.
Returns tuple of a boolean and a list of strings. The boolean indicates if the routes match,
and the list contains the values of the url parameters from the ``other`` route.
Examples::
route = _HTTPRoute("/example", HTTPMethod.GET)
other1 = _HTTPRoute("/example", HTTPMethod.GET)
route.matches(other1) # True, []
other2 = _HTTPRoute("/other-example", HTTPMethod.GET)
route.matches(other2) # False, []
...
route = _HTTPRoute("/example/<parameter>", HTTPMethod.GET)
other1 = _HTTPRoute("/example/123", HTTPMethod.GET)
route.matches(other1) # True, ["123"]
other2 = _HTTPRoute("/other-example", HTTPMethod.GET)
route.matches(other2) # False, []
"""
if self.method != other.method:
return False, []
if not self._contains_parameters:
return self.path == other.path, []
regex_match = re.match(self.path, other.path)
if regex_match is None:
return False, []
return True, regex_match.groups()
def __repr__(self) -> str:
return f"_HTTPRoute(path={repr(self.path)}, method={repr(self.method)})"
class _HTTPRoutes:
"""A collection of routes and their corresponding handlers."""
def __init__(self) -> None:
self._routes: List[_HTTPRoute] = []
self._handlers: List[Callable] = []
def add(self, route: _HTTPRoute, handler: Callable):
"""Adds a route and its handler to the collection."""
self._routes.append(route)
self._handlers.append(handler)
def find_handler(self, route: _HTTPRoute) -> Union[Callable, None]:
"""
Finds a handler for a given route.
If route used URL parameters, the handler will be wrapped to pass the parameters to the
handler.
Example::
@server.route("/example/<my_parameter>", HTTPMethod.GET)
def route_func(request, my_parameter):
...
request.path == "/example/123" # True
my_parameter == "123" # True
"""
if not self._routes:
return None
found_route, _route = False, None
for _route in self._routes:
matches, url_parameters_values = _route.match(route)
if matches:
found_route = True
break
if not found_route:
return None
handler = self._handlers[self._routes.index(_route)]
def wrapped_handler(request):
return handler(request, *url_parameters_values)
return wrapped_handler
def __repr__(self) -> str:
return f"_HTTPRoutes({repr(self._routes)})"